Chapter III_America's Munitions 1917-1918

MOBILE FIELD ARTILLERY.

The chance observer might assume that once the Ordnance Department

had succeeded in putting in production the cannon of various sizes

described in the preceding chapter the battle of providing artillery

was as good as won. But such was not the case. Even after the ponderous

tubes had come finished from the elaborate processes of the steel

mills, the task of the ordnance officers had only just begun. Each one

of these guns had to be rendered mobile in the field and it had to be

equipped with a mechanism to take up the retrograde shock of firing

(the "kick") and to prevent the weapon from leaping out of aim at each

discharge.

Mobility to a gun is given by the carriage on which it rides. The

device which absorbs the recoil and restores the gun to position is

called the recuperator (in the case of the hydropneumatic French

design) or the recoil mechanism. Carriage and recuperator, or recoil

mechanism, together are known as the mount.

The forging, boring, reinforcing, machining, and finishing of the

gun body is not half the battle of manufacturing a modern military

weapon; it is scarcely one-third of it. No ordnance officer of 1917-18

will ever forget the heartbreaking experiences of manufacturing the

mounts, a work which went along simultaneously with the production of

the cannon themselves. The manufacture of carriages often presented

engineering and production problems of the most baffling sort. As

to the recuperators, a short analysis of the part they play in the

operation of a gun will indicate something of the nature of the project

of building them in quantities.

The old schoolbook axiom that action and reaction are equal has a

peculiar emphasis when applied to the firing of a modern piece of

high-power artillery. The force exerted to throw a heavy projectile 7

miles or more from the muzzle of a gun is equally exerted toward the

breach of the weapon in its recoil. Some of these forces handled safely

and easily by mechanical means are almost beyond the mind's grasp.

Not long ago a touring car, weighing 2 tons, traveled at the rate of

120 miles an hour along a Florida beach. Conceive of such a car going

337 miles an hour, which is much faster than any man ever traveled;

then conceive of a mechanism which would stop this car, going nearly

6 miles a minute, stop it in 45 inches of space and half a second

of time, without the slightest injury to the automobile. That is

precisely the equivalent of the feat performed by the recuperator of a

240-millimeter howitzer after a shot.

Conceive of a 150,000-pound locomotive traveling at 53.3 miles an hour.

The action of the 240-millimeter recuperator after a shot is equivalent

to stopping that locomotive in less than 4 feet in half a second

without damage.

The forging for the 155-millimeter howitzer's recuperator is a block

of steel weighing nearly 2 tons--in exact figures, 3,875 pounds. This

must be bored and machined out until it weighs, with the accessory

parts of the complete recuperator placed on the scales with it, only

870 pounds. It is scarcely fair to a modern hydropneumatic recuperator

to say that it must be finished with the precision of a watch. It must

be finished with a mechanical nicety comparable only to the finish of

such a delicate instrument as a navigator's sextant or the mechanism

which adjusts the Lick telescope to the movement of the earth. No heavy

articles ever before turned out in American workshops required in their

finish the degree of microscopic perfection the recuperators called for.

We adopted from the French, the greatest of all artillery builders,

four recuperators--one for the 75-millimeter gun, one for the

155-millimeter gun, another for the 155-millimeter howitzer, and the

fourth for the 240-millimeter howitzer. These mechanisms had never been

built before outside of France. Indeed, one could find pessimists ready

to say that none but French mechanics could build them at all and that

our attempt to duplicate them could end only in failure. Yet American

mechanical genius "licked" every one of these problems, as the men

in the greasy overalls say, and did it in little more than a year of

time after the plans came to the workshops. There was not one of these

beautiful mechanisms, in France the product of patient handiwork on the

part of metal craftsmen of deep and inherited skill, that eventually

did not become in American workshops a practical proposition of

quantity production.

The problem of building French recuperators in the United States, in

short, may be regarded as the crux of the whole American ordnance

undertaking in the war against Germany, the index of its success. It

presented the most formidable challenge of all to American industrial

skill. There were men whose opinion had to be considered and who were

convinced that it was impracticable to attempt to produce French

recuperators here. Although the superiority of these recoil devices

in their respective classes were universally conceded, Germany had

never been able to make them, while England, with the cooperation of

the French ordnance engineers freely offered, did not attempt them.

The French built them one by one, as certain custom-built and highly

expensive automobiles are produced. When American factories proposed to

produce French recuperators not only but to manufacture them by making

parts and assembling them according to the modern practice of quantity

production, the ranks of the skeptics increased.

Yet, as we have said, the thing was done. The first of these

recuperators ever produced outside of the French industry were produced

in America and manufactured by typically American quantity methods.

The first of these recuperators to come into quantity production was

that for the 155-millimeter howitzer. Rough forgings began to be turned

out in heavy quantities by the Mesta Machine Co. in the spring of 1918,

while the Watertown Arsenal, the other contractor, reached quantity

production in rough forgings in September, 1918. At their special

recuperator plant at Detroit the Dodge Bros. turned out the first

finished 155-millimeter howitzer recuperator in July, 1918, and went

into quantity production with them in September, producing 495 in the

month of November alone, and turning out up to the end of April, 1919,

the great number of 1,601 of them.

Next in order of time to be conquered as a factory problem was the

155-millimeter gun recuperator. The rough forgings at the Carnegie

Steel Co., the sole contractor, were in quantity production in the

spring of 1918. The first of these recuperators finished came from the

Dodge plant in October, 1918; and although 30 issued from the plant

and were accepted before the end of the year, quantity production may

be said to have started on January 1, 1919, when the factory began

producing them at the rate of more than four a day. In March the high

mark of 361 recuperators was reached, and the total production up to

the end of April was 880.

The heavy 240-millimeter howitzer recuperator was third to come into

quantity production. The rough forgings were being turned out in

quantity in the spring of 1918 by the Carnegie Steel Co., while the

Watertown Arsenal, the other contractor, produced a number of these

rough forgings in August, 1918. The two contractors for finishing and

turning out the complete recuperators were the Otis Elevator Co., at

its Chicago plant, and the Watertown Arsenal. The arsenal produced the

pilot recuperator in October, 1918. In January the Otis Elevator Co.

produced its first four, while quantity production began in February,

1919, both contractors that month sending out 19 recuperators, a number

which may be regarded as good quantity when the size of this mechanism

is taken into consideration. Both plants together in April turned out

the large number of 89 recuperators for the 240.

Last to come through to quantity production was the hardest of the four

to build, the one that promised to defy American industry to build it

at all--the 75-millimeter gun recuperator. The two contractors for the

rough forgings for this recuperator were the Carbon Steel Co. and the

Bucyrus Co. The Carbon Steel Co. was in large series production of them

in the spring of 1918, and the Bucyrus Co. reached the quantity basis

of manufacture in October, 1918. In that month alone both contractors

together turned out 1,305 sets of forgings.

The machining and finishing of the 75 recuperator was in the hands

of the Rock Island Arsenal and the Singer Manufacturing Co., which

built a costly plant especially for the purpose at Elizabethport,

N. J. The first recuperator of this size to appear and be accepted

under the severe tests came from the arsenal in October. Thereafter

the production ceased for a while. The contractors indeed built

recuperators in this period, but the recuperators could not pass the

tests. The machining and production of parts seemed to be as perfect as

human skill could accomplish, but still the devices would not function

perfectly. Adjustments, seemingly of the most microscopical and trivial

sort, had to be made--there was trouble with the leather of the valves

and with oil for the cylinders. These matters, which could scarcely

cause any delay at all in the production of less delicate machinery,

indicate the infinite care which had to be employed in the manufacture

of the recuperators. At length the producers smoothed out the obstacles

and learned all the secrets and necessary processes, and then the

75-millimeter recuperators began to come--2 in January, 1919, and then

13 in February, 20 in March, and 23 in April.

It should be remembered that by quantity production in this particular

is meant the production in quantity of recuperators of such perfect

quality as to pass the inspection of the Government and to be accepted

as part of our national ordnance equipment. In this inspection the

Government was assisted by French engineers sent from the great

artillery factories in France which had designed the recuperators and

which until the successful outcome of the American attempt were their

sole producers. Such inspection naturally required that the American

recuperators should be the equals of their French prototypes in every

respect.

Because the production of French recuperators stands at the summit of

American ordnance achievement, here at this point, before there is

given any account of the manufacture of field artillery, the theme

of this chapter, a performance table is inserted to show the records

written by the various concerns engaged in making these devices.

_American acceptances of recuperators by firms on Army ordnance

orders only._

=========================+=================================================

| 1918

+-------+-----+-------+-------+-----+------+------

|July 1.| | | ber. | ber.| ber. | ber.

-------------------------+-------+-----+-------+-------+-----+------+------

| | | | | | |

| | | | | | |

Carbon Steel Co. | 259 | 259 | 254 | 750 |1,005| 300 | 552

| | | | | | |

Bucyrus Co. | | | 29 | 78 | 300| 173 | 111

+-------+-----+-------+-------+-----+------+------

Total | 259 | 259 | 283 | 828 |1,305| 473 | 663

+=======+=====+=======+=======+=====+======+======

| | | | | | |

Co. | | | | | | |

| | | | | | |

Rock Island Arsenal | | | | | 1| |

+-------+-----+-------+-------+-----+------+------

Total | | | | | 1| |

+=======+=====+=======+=======+=====+======+======

| | | | | | |

| | | | | | |

Mesta Machine Co. | 676 | 646 | 648 | 899 |1,080| 226 |

| | | | | | |

Watertown Arsenal | | | | 160 | 80| 80 |

+-------+-----+-------+-------+-----+------+------

Total | 676 | 646 | 648 | 1,059 |1,160| 306 |

+=======+=====+=======+=======+=====+======+======

| | | | | | |

Dodge Bros. | | 1 | 27 | 249 | 285| 495 | 403

| | | | | | |

| | | | | | |

| | | | | | |

Carnegie Steel Co. | 212 | 213 | 229 | 269 | 401| 389 | 21

| | | | | | |

| | | | | | |

Dodge Bros. | | | | | 1| 10 | 19

+=======+=====+=======+=======+=====+======+======

| | | | | | |

| | | | | | |

Carnegie Steel Co. | 286 | 99 | 115 | 61 | 70| 79 |

| | | | | | |

Watertown Arsenal | | | 21 | | | |

+-------+-----+-------+-------+-----+------+------

Total | 286 | 99 | 136 | 61 | 70| 79 |

+=======+=====+=======+=======+=====+======+======

| | | | | | |

| | | | | | |

Watertown Arsenal | | | | | 1| |

+-------+-----+-------+-------+-----+------+------

Total | | | | | 1| |

=========================+=======+=====+=======+=======+=====+======+======

=========================+===========================+========+=====+========

| 1919 | Total, |Total| Total,

+------+------+------+------+Nov. 11,|1918.|Apr. 30,

Item, process, and firm. | Jan- |Febru-|March.|April.| 1918. | | 1919.

|uary. | ary. | | | | |

-------------------------+------+------+------+------+--------+-----+--------

| | | | | | |

| | | | | | |

Carbon Steel Co. | 407 | 49 | | | 2,600 |3,379| 3,835

| | | | | | |

Bucyrus Co. | | 68 | | | 435 | 691| 759

+------+------+------+------+--------+-----+--------

Total | 407 | 117 | | | 3,035 |4,070| 4,594

+======+======+======+======+========+=====+========

| | | | | | |

Co. | | | 3 | 8 | | | 11

| | | | | | |

Rock Island Arsenal | 2 | 13 | 17 | 15 | 1 | 1| 48

+------+------+------+------+--------+-----+--------

Total | 2 | 13 | 20 | 23 | 1 | 1| 59

+======+======+======+======+========+=====+========

| | | | | | |

| | | | | | |

Mesta Machine Co. | 49 | | 31 | | 4,000 |4,175| 4,255

| | | | | | |

Watertown Arsenal | 25 | 1 | | | 268 | 320| 346

+------+------+------+------+--------+-----+--------

Total | 74 | 1 | 31 | | 4,268 |4,495| 4,601

+======+======+======+======+========+=====+========

| | | | | | |

Dodge Bros. | 141 | | | | 796 |1,460| 1,601

| | | | | | |

| | | | | | |

| | | | | | |

Carnegie Steel Co. | | | | | 1,480 |1,734| 1,734

| | | | | | |

| | | | | | |

Dodge Bros. | 116 | 270 | 361 | 103 | | 30| 880

+======+======+======+======+========+=====+========

| | | | | | |

| | | | | | |

Carnegie Steel Co. | | | | | 678 | 710| 710

| | | | | | |

Watertown Arsenal | | | | | 21 | 21| 21

+------+------+------+------+--------+-----+--------

Total | | | | | 699 | 731| 731

+======+======+======+======+========+=====+========

| | | | | | |

Otis Elevator Co. | 4 | 14 | 41 | 62 | | | 121

| | | | | | |

Watertown Arsenal | | 5 | 19 | 27 | 1 | 1| 52

+------+------+------+------+--------+-----+--------

Total | 4 | 19 | 60 | 89 | 1 | 1| 173

=========================+======+======+======+======+========+=====+========

The process of manufacture of recuperators requires four

steps--forging, rough machining, finish machining, and assembling. In

the case of 155-millimeter howitzer recuperators all the machining

was done by one firm; in the other cases rough machining was done by

various firms, including, in the case of the 155-millimeter gun and

240-millimeter howitzer recuperators, the firms doing the forging.

Complete records of rough machining are not available.

In discussing here, therefore, the production of field artillery in the

war period, we are concerned chiefly with carriages and recuperators,

for they offered the major difficulties. Since the production of gun

bodies for these various units has been taken up in the preceding

chapter, such reference to them as is necessary will be brief. For the

sake of additional clearness in the mind of the reader inexpert in

these things, the line should be sharply drawn between field artillery

and the so-called railway artillery, which was also mobile to a limited

degree. The mobile field artillery consisted of all rolling guns or

caterpillar guns up to and including the 240-millimeter howitzer in

size; and also included the antiaircraft guns of various sizes. All

mobile guns of larger caliber than the 240-millimeter howitzer were

mounted on railroad cars.

The list of the mobile field artillery weapons in manufacture here

during the war period was as follows:

The little 37-millimeter gun, the so-called infantry cannon, one of

which two husky men could lift from the ground--a French design;

The 75-millimeter guns--three types of them--the French 75, adopted

bodily by the United States; our own 3-inch gun redesigned to the

French caliber; and the British 3.3-inch gun, similarly redesigned;

The 4.7-inch gun of American design;

The 5-inch and 6-inch guns, taken from our coast defenses and naval

stores and placed on mobile mounts;

The 155-millimeter gun, a French weapon with a barrel diameter of

approximately 6 inches;

The 155-millimeter howitzer, also French;

The 8-inch and 9.2-inch howitzers, British designs, being manufactured

in the United States when war was declared;

The 240-millimeter howitzer, French and American; and, finally,

The antiaircraft guns.

In modern times, but prior to 1917, the United States had designed

types of field-artillery weapons and produced them in quantities shown

by the following tabulation:

Pieces.

2.95-inch mountain gun 113

3-inch gun 544

4.7-inch gun 60

5-inch gun 70

6-inch howitzer 40

7-inch howitzer 70

---

Total 897

A comparison of this list with the enumeration above of weapons

put in production during the war against Germany indicates that we

greatly expanded our artillery in types. That we were able to do this

at the outset and go ahead immediately with the production of many

weapons strange and unknown to our experience, without waiting to

develop models and types of our own, is due solely to the generosity

of the governments of France and Great Britain, with whom we became

associated. We manufactured in all eight new weapons, taking the

designs of three of them from the British and of five from the French.

It might seem to the uninitiated that the way of the United States to

a great output of artillery would be made smooth by the action of the

British and French Governments in agreeing to turn over to us without

reservation the blue prints and specifications that were the product of

years of development in their gun plants. Yet this was only relatively

true. In numerous instances we were not able to secure complete

drawings until months after we had entered the war, due to the practice

of continental manufacturers that intrusts numerous exact measurements

to the memories of the mechanics working in their shops. Consequently

it required several months to complete drawings, and when we received

them our troubles had only begun.

First there came the problem of translating the plans after we received

them. All French dimensions are according to the metric system. A

millimeter is one one-thousandth part of a meter, and a meter is 39.37

inches. An inch is approximately 0.0254 meter. Thus to translate French

plans into American factory practice involves hundreds of mathematical

computations, most of them carried out to decimals of four or five

places. Moreover, the French shop drawings are put down on an angle

of projection different from what is used in this country. This

fact involved the recasting of drawings even when the metric system

measurements were retained. When it is considered that such a mechanism

as the recuperator on the 155-millimeter gun involves the translation

of 416 drawings, the fact that the preparation of French plans for our

own use never took more than two months is remarkable, particularly so

since it was hard to find in the United States draftsmen and engineers

familiar with such translation work.

Once our specifications were worked out from the French plans, it then

became necessary to find American manufacturers willing to bid on the

contracts. The average manufacturer would look at these specifications,

realize what a highly specialized and involved sort of work would be

required in the production of the gun carriages or recoil mechanisms,

and shake his head. In numerous instances no such work had ever before

been attempted in the United States.

However, as the result of efforts on the part of the Government an

increased capacity for producing mobile field artillery was created as

follows:

At Watertown, N. Y., the New York Air Brake Co., as agent for the

United States, constructed a completely new factory to turn out 25 gun

carriages a month for the 75-millimeter guns, model 1916--the American

3-inch type modified to the French dimensions.

At Toledo, Ohio, increased facilities were put up at the plant of

the Willys-Overland Co. to manufacture a daily output of 17 French

75-millimeter gun carriages, model 1897.

At Elizabethport, N. J., the Singer Manufacturing Co. erected for

the Government a complete new factory for finishing daily 17 French

75-millimeter recuperators.

At New Britain, Conn., the plant of the New Britain Machine Co. was

adapted and increased facilities were created for the manufacture of

two 3-inch antiaircraft gun carriages a day.

At Detroit, Mich., Dodge Bros., as agents for the Government, erected

an entirely new factory, costing in the neighborhood of $11,000,000

to give the final machining to the rough-machine forgings for five

recuperators daily for the 155-millimeter gun and to machine completely

the parts for twelve recuperators daily for the 155-millimeter

howitzer. Their huge new plant for this purpose established a record

for rapidity of construction in one of the most severe winters of

recent history.

At the plant of the Studebaker Corporation at Detroit, facilities were

extended for turning out three carriages a day for the 4.7-inch guns.

At Plainfield, N. J., extended facilities were created at the factory

of the Walter Scott Co. for manufacturing 20 carriages a month for the

4.7-inch guns.

At Worcester, Mass., at the plant of the Osgood Bradley Car Co.

increased facilities were built for the daily manufacture of five

carriages for the 155-millimeter howitzers.

At Hamilton, Ohio, at the works of the American Rolling Mill Co.,

extensions were made to provide for the manufacture each day of three

carriages for the 155-millimeter howitzers.

The plant of the Mesta Machine Co., at West Homestead, Pa., near

Pittsburgh, was extended to the enormous capacity of turning out the

forgings for 40 recuperators a day for the 155-millimeter howitzers.

Extensively increased facilities were made at the shops of the Standard

Steel Car Co., at Hammond, Ind., for the daily output of two carriages

for the 240-millimeter howitzers.

Increased facilities were created in the plant of the Otis Elevator

Co., Chicago, Ill., for the finish machining of the equivalent in parts

of two and one-half recuperators a day for the 240-millimeter howitzers.

Large extensions were made to the plant of the Morgan Engineering Co.,

Alliance, Ohio, for the manufacture monthly of 20 improvised mounts for

the 6-inch guns taken from the seacoast fortifications.

The facilities of the United States arsenals at Watertown, Mass., and

at Rock Island, Ill., for the manufacture of field-gun carriages and

recuperators were greatly increased.

This carriage construction for the big guns required the closest kind

of fine machine work and fittings where the brake or recuperator

construction entered the problem, and the great plants built for this

purpose of turning out carriages and recuperators were marvels for the

rapidity of their construction, the speed with which they were equipped

with new and intricate tools, and the quality of their output.

Every mobile gun mount must be equipped with a shield of armor plate.

The size of the artillery project may be read in the fact that our

initial requirement for armor for the guns ran to a total of 15,000

tons to be produced as soon as it could be done. Now, we had no real

source for getting armor in such large quantities, because the previous

demands of our artillery construction had never called for it. The

prewar manufacturers of artillery armor were three in number--the

Simmons Manufacturing Co., of St. Louis; Thomas Disston & Sons, of

Philadelphia; and the Crucible Steel Co. To meet the new demand two

armor sources were developed--the Mosler Safe Co. plant of the Standard

Ordnance Co. and the Universal Rolling Mill Co. The process of building

this armor had been a closely guarded secret in the past, a fact

entailing extended experiments in the new plants before satisfactory

material could be obtained.

The new artillery program required the manufacture of 120,000 wheels

of various types and sizes for the mobile carriages. The Rock Island

Arsenal and two commercial concerns prior to the war had been building

artillery wheels in limited quantities. One completely new plant had

to be erected for the manufacture of wheels, while seven existing

factories were specially equipped for this work. We had to develop new

sources of supply of oak and hickory and to erect dry kilns especially

for the wheel project.

The largest order for rubber tires in the history of the American

rubber industry was placed as one relatively small phase of the

artillery program, the order amounting to $4,250,000. Rubber tires

on the wheels of all the heavier types of artillery carriages, so

that the units might be drawn at good speed by motor vehicles, was

essentially an American innovation. No tires of this size had ever been

manufactured in this country. Consequently it was necessary for the

firms who got the orders to build machinery especially designed for the

purpose.

With practically all of the manufacturers of the American metal-working

industries clamoring for machine tools, and with some branches of the

Government commandeering the machine-tool shops in whole sections of

the country, it is evident that the necessity for the heavier types

of machine tools required by the manufacturers of artillery material

offered a weighty problem at the outset. In fact, the machine-tool

supply was never adequate at any time, and the shortage of this

machinery hampered and impeded to a great degree the speed of our

artillery production.

The Nation was raked with a fine-toothed comb for shop equipment.

The Government went to almost any honorable length to procure this

indispensable tooling. For instance, when the Dodge plant at Detroit

was being equipped to manufacture the 155-millimeter recuperators, the

Government agents discovered trainloads of machinery consigned to the

Russian government and awaiting shipment. These tools were commandeered

on the docks. One huge metal planer had dropped overboard while it was

being lightered to the ocean tramp that was to carry it to a Russian

port. Government divers fixed grappling hooks to this machine, and it

was brought to the surface and shipped at once to the Dodge plant.

The 3-inch gun which we had been building for many years prior to the

war was a serviceable and efficient weapon; but still we were unable to

put it into production immediately as it was. Our earliest divisions

in France, under the international arrangement, were to be equipped

by the French with 75-millimeter guns; while we, on this side of the

water, reaching out for all designs of guns of proven worth, expected

to manufacture the 75's in large numbers in this country. The French 75

in its barrel diameter is a fraction of an inch smaller than our 3-inch

gun, the exact equivalent of 75 millimeters being 2.95275 inches. Thus,

if we built our own 3-inch gun (and the British 3.3-inch gun, as we

intended) and also went ahead with the 75-millimeter project on a great

scale, we should be confronted by the necessity of providing three

sorts of ammunition of almost the same size, with all the delays and

confusion which such a situation would imply. Consequently we decided

to redesign the American and British guns to make their bores uniformly

75 millimeters, thus simplifying the ammunition problem and making

available to us in case of shortage the supplies of shell of this size

in France.

With all of the above considerations in mind, it is evident now, and it

was then, that we could not hope to equip our Army with American-built

artillery as rapidly as that Army could be collected, trained, and sent

to France; and this was particularly true when in the spring of 1917

the Army policy was changed to give each 1,000,000 men almost twice

as many field guns as our program had required prior to that date.

Consequently, when on June 27, 1917, the Secretary of War directed the

Chief of Ordnance to provide the necessary artillery for the 2,000,000

men who were to be mobilized in 1917 and the first half of 1918, the

first thought of our officers was to find outside supplies of artillery

which we could obtain for an emergency that would not be relieved

until our new facilities had reached great production.

We found this source in France. The French had long been the leading

people in Europe in the production of artillery, and even the great

demands of the war had not succeeded in utilizing the full capacity

of their old and new plants. Two days later, on June 29, 1917, the

French high commissioner, by letter, offered us in behalf of France

a daily supply of five 75-millimeter guns and carriages, beginning

August 1, 1917. The French also offered at this time to furnish us with

155-millimeter howitzers; and on August 19, 1917, the French Government

informed Gen. Pershing that each month, beginning with September, he

could obtain twelve 155-millimeter Filloux guns and carriages from the

French factories.

Before the signing of the armistice 75-millimeter guns to the number

of 3,068 had been ordered from the French, and of this number 1,828

had been delivered. Of 155-millimeter howitzers, 1,361 had been

ordered from the French and 772 delivered before November 11, 1918.

Of 155-millimeter guns, 577 had been ordered from the French and 216

delivered previous to the granting of the armistice.

From British plants we ordered 212 Vickers-type 8-inch howitzers, and

123 had been delivered before the armistice had been signed; while of

9.2-inch howitzers, Vickers model, 40 of an order for 132 had been

completed. In addition to this, 302 British 6-inch howitzers were in

manufacture in England for delivery to us by April 1, 1919. These

figures, with the exception of those relating to the order for British

6-inch howitzers, do not include the arrangements being made by this

Government during the last few weeks of hostilities for additional

deliveries of foreign artillery.

As to our own manufacture of artillery, when we had conquered all

the difficulties--translated the drawings, built the new factories,

equipped them with machine tools and dies, gages, and other fixtures

needed by the metal workers, and had mobilized the skilled workers

themselves--we forged ahead at an impressive rate. When the armistice

was signed we were turning out 412 artillery units per month. Compare

this with Great Britain's 486 units per month in the fall of 1918 and

measure our progress, remembering that England had approximately three

years' head start. Compare it with the French monthly production of 659

units per month, and remember that France was the greatest artillery

builder in the world. When it came to the gun bodies themselves we

obtained a monthly output of 832, as against Great Britain's 802 and

France's 1,138. And our artillery capacity was then, in the autumn of

1918, only coming into production.

In the war period--April 6, 1917, to November 11, 1918--we produced

2,008 complete artillery units, as against 11,056 turned out by France

and 8,065 completed by Great Britain in the same period. In those 19

months we turned out 4,275 gun bodies, while in the same months France

produced 19,492 and Great Britain 11,852.

THE 37-MILLIMETER INFANTRY FIELD GUNS

The smallest weapon of all the field guns we built was the French

37-millimeter gun, the diameter of its bore being about 1½ inches

in our measurements, the figure being 1.45669 inches. This was the

so-called infantry field gun, to be dragged along by foot soldiers when

they are making an advance. Its chief use in the war was in breaking

up the German concrete pill boxes, machine gun nests, and other strong

points of enemy resistance. In service it was manned by infantrymen

instead of artillerists, a crew of eight men handling each weapon,

the squad leader being the gunner. One of the men of the crew was the

loader, and he was likewise able to fire the piece. The other six men

served as assistants.

The 37-millimeter outfit as it exists to-day consists of the gun,

with a split trail, mounted on axle and wheels. By means of a trailer

attachment on the ammunition cart it can be drawn by one horse or one

mule. The ammunition cart itself is merely a redesigned machine-gun

ammunition vehicle. The wheels and axle can easily be removed and left

a short distance in the rear of the place where it is desired to set up

the gun. The whole outfit weighs only 340 pounds and is about 6 feet

long.

The gun rests on its front leg which is dropped to form a tripod with

the two legs of the split trail. The gun proper can be removed from the

trail and the sponge staff can be inserted in the barrel through the

opened breech. Two men can bear this part of the weapon in advancing

action. Two other men are able to carry the trail, when its legs are

locked together, while the four other members of the squad bring along

the boxes of ammunition.

The ammunition cart holds 14 ammunition boxes, each containing

16 rounds. A spare-parts case, strapped to the trail, contains a

miscellaneous assortment of such parts as can readily be handled in the

field. A tool kit in a canvas roll is also transported on the cart,

along with entrenching tools and other accessories.

Equipped with a telescopic sight for direct fire and a quadrant, or

collimating sight, for indirect fire, great accuracy is obtained by

this small piece of artillery. The length of the barrel of the gun

proper is 20 calibers, which means that it is 20 times 37 millimeters

in length, or about 29 inches. The length of the recoil when the gun is

fired is 8 inches.

Two types of ammunition were provided for this gun at first; but,

as the low-explosive type was not so effective as desired, it was

abandoned entirely in favor of the high-explosive type contained in

a projectile weighing 1¼ pounds. This projectile is loaded with 240

grains of T. N. T. and detonated by a base percussion fuse. The range

of the gun is 3,500 meters, or considerably more than 2 miles. Only

three to six shots from this gun were found to be necessary to demolish

an enemy machine gun emplacement or other strongly held position.

In the great war the 37-millimeter gun found itself and proved its

usefulness. The original model had been designed at the Puteaux Arsenal

in France in 1885; but it was not until after 1914 that the weapon was

produced in quantities.

In this country we took up the production of 37-millimeter guns in

October, 1917. While our shops were tooling up for the effort, 620 of

these weapons were purchased from the French and turned over to the

American Expeditionary Forces. For the purposes of greater speed in

manufacture our executives took the gun apart and divided it into three

groups, known as the barrel group, the breech group, and the recoil

group. Additional to these, as a manufacturing proposition, were the

axle and wheels and the trail.

The barrel group went to the Poole Engineering & Machine Co., of

Baltimore, Md., who subcontracted for some of the parts to the Maryland

Pressed Steel Co., of Hagerstown, Md. The breech group was manufactured

by the Krasberg Manufacturing Co., of Chicago. The C. H. Cowdrey

Machine Works, of Fitchburg, Mass., turned out the recoil mechanisms.

The axles and wheels were built by the International Harvester Co.,

of Chicago. The trails were turned out by the Universal Stamping &

Manufacturing Co., also of Chicago.

When crated for overseas shipment, the gun, ammunition cart, and all

accessories, weighed 1,550 pounds and occupied about 15 cubic feet of

space.

The first delivery of completed 37-millimeter guns from our factories

was made in June, 1918, and at the cessation of hostilities

manufacturers were turning out the guns at the rate of 10 per day.

Between June and November 122 American-built 37-millimeter guns were

shipped abroad, and more were ready to be sent over when the armistice

was signed. The gun had been so successful in use abroad that our

original order of 1,200 had been increased to 3,217 before the signing

of the armistice, including the 620 purchased from the French.

The various groups of this gun were shipped to the plant of the

Maryland Pressed Steel Co., Hagerstown, Md., for assembly and were

there tested at a specially built proving ground, 8 miles from the

factory.

Three 37's were issued to each infantry regiment, making one for each

battalion. The required equipment for a division was, therefore, 12

weapons.

[Illustration: THE 37-MILLIMETER INFANTRY CANNON.]

[Illustration: TWO VIEWS OF 75-MILLIMETER FIELD GUN, MODEL 1918

(AMERICAN).]

_Figures on 37-millimeter gun production._

Guns procured from the French Government 620

Guns ordered manufactured in United States, October, 1917 1,200

Increase in order, September, 1918 1,397

Total number ordered in United States 2,597

Total number of guns completed prior to the signing of the armistice 884

Guns delivered for overseas shipment prior to the signing of the 300

armistice

Guns shipped to various camps in this country 26

Guns shipped to other points in this country 4

On hand at Hagerstown Arsenal, proof fired 425

Completed and ready for proof firing 129

THE 75-MILLIMETER GUNS.

Next in order in the upward scale of sizes we come to the 75-millimeter

gun, which was by far the most useful and most used piece of artillery

in the great war. In fact the American artillery program might be

divided in two classes, the 75's in one class, and all other sizes

in the other, since it may be said practically that for every gun of

another size produced we also turned out a 75. In number the 75's made

up almost half of our field artillery. The 75-millimeter gun threw

projectiles weighing between 12 and 16 pounds and it had an effective

range of over 5½ miles.

We approached the war production of this weapon with three types

available for us to produce--our own 3-inch gun; its British cousin

the 3.3-inch gun or 18-pounder; and the French 75-millimeter gun, with

its bore of 2.95275 inches. The decision to adopt the 75-millimeter

size and modify the other two guns to this dimension, giving us

interchangeability of ammunition with the French, was an historic

episode in the American ordnance development of 1917.

While in 1917 the French with their excess manufacturing capacity

began work on our first orders for 1,068 guns of this size to supply

our troops during the interim until American factories could come into

production, we were preparing our factories for the effort. Roughly

speaking the 75 consists of a cannon mounted on a two-wheeled support

for transportation purposes. This support also provides a means for

aiming by suitable elevating and traverse mechanisms. As previously

explained, a recoil mechanism is also provided to absorb the shock

of firing, allowing a certain retrograde movement of the cannon and

then returning it in position for the next shot--returning it "into

battery," as the artillerists say. By its recuperator device the field

gun of to-day is chiefly distinguished from its brother of the latter

part of the nineteenth century. Without a recuperator the gun would

leap out of aim at each shot and would have to be pointed anew; but one

with a recuperator needs to be pointed only at the beginning of the

action.

When we entered the war we found ourselves with an equipment of 544

field guns of the old 3-inch model of 1902. This gun had a carriage

provided with the old-style single trail. By 1913, however, we had

been experimenting with the split trail and it had been strongly

recommended by our ordnance experts; and in 1916 we had placed orders

for nearly 300 carriages of the split-trail type, which had come to be

known as Model 1916. Of these orders 96 carriages were to come from the

Bethlehem Steel Co., and the remainder from the Rock Island Arsenal.

Meanwhile for some time the Bethlehem Steel Co. had been engaged in

turning out carriages for the British 3.3-inch guns. Here was capacity

that might be utilized to the limit; and, accordingly, in May, 1917,

we ordered from the Bethlehem Co. 268 of the British carriages. At the

same time we ordered from the same company approximately 340 of our own

Model 1916 carriages at a cost of $3,319,800. A few weeks later the

decision had been made to make all our guns of this sort conform to the

French 75-millimeter size, and these British and American carriages

contracted for in May were ordered modified to take 75-millimeter

guns. The carriages needed little modification and the guns not much.

Subsequently, in rapid succession we placed orders with the Bethlehem

Steel Co., calling for the construction of an additional 1,130 of the

British carriages, all of them to be adapted to 75-millimeter guns.

Next it was the concern of the Ordnance Department to find other

facilities for manufacturing carriages for these weapons. The artillery

committee of the Council of National Defense located the New York Air

Brake Co. as a concern willing to undertake this work; and in June,

1917, this company signed a contract to produce 400 American model 1916

carriages at a cost of $3,250,000.

By December we had the drawings for the French carriages of this

size and made a contract with the Willys-Overland Motor Car Co. to

produce 2,927 of them. The table at the end of this section shows the

production attained at these various plants.

The manufacture of carriages for the 75's produced concrete results, as

our factories here were turning them out for us at the rate of 393 per

month when the fighting ceased, and our contract plants in France were

making 171 per month. In all we received from American factories 1,221

carriages. At the rate of increase we would have been building 800

carriages per month by February, 1919.

It may be said we were thoroughly impressed with the difficulties

attached to the transplanting to this country of the manufacture of

French 75-millimeter recuperators. It was a question whether this

device could possibly be built by any except the French mechanics

trained by long years in its production. At first it seemed that we

could secure no manufacturer at all who would be willing to assume

such a burden. Not until February, 1918, were complete drawings and

specifications of the recuperator received from France. At length

the Singer Manufacturing Co., builders of sewing machines, consented

to take up this new work, and on March 29 the company contracted to

produce 2,500 recoil systems for the 75-millimeter gun carriages. In

April, 1918, the Rock Island Arsenal was instructed to turn out 1,000

of these recuperators.

[Illustration: TWO VIEWS OF THE FRENCH 75-MILLIMETER GUN.

This type of gun has been used by the French Army since 1897,

and was the gun most used by the Allies in the Great War. This

gun throws a shell weighing 12.3 pounds a distance of 8,400

meters or shrapnel weighing 16 pounds a distance of 9,000

meters. The weight of the gun and carriage is 2,657 pounds. The

service muzzle velocity of the shell is 1,805 feet per second,

while for shrapnel it is 1,755 feet per second.]

[Illustration: THE 75-MILLIMETER FIELD GUN, MODEL 1917 (BRITISH).

This gun throws a shell weighing 12.3 pounds a distance of

8,300 meters, and 16 pounds of shrapnel a distance of 8,900

meters. The weight of the gun and carriage is 2,887 pounds.

Its muzzle velocity for shell is 1,750 feet a second and for

shrapnel 1,680 feet a second.]

The production of gun bodies for the 75-millimeter units was

quite satisfactory. The Bethlehem Co., the Wisconsin Gun Co., the

Symington-Anderson Co., and the Watervliet Arsenal were the contractors

who built the gun bodies. Gun bodies of three types, but all of the

same 75-millimeter bore, were ordered--the American type (the modified

3-inch gun), the British type (the modified 3.3-inch gun), and the

French type.

Our ordnance preparation would have given us enough 75's for the

projected army of 3,360,000 men on the front in the summer of 1919,

together with appropriate provision for training in the United States.

Of the 75's built in this country, 143 units were shipped to the

American Expeditionary Forces before the armistice went into effect.

Meanwhile the French had delivered to our troops 1,828 units of this

size. The total equipment of 75's for our Army in France from all

sources thus amounted to 1,971 guns with their complete accessories.

------------------------+------------------------+------+------+------+------

| | or- | comp-|float-| com-

| | |ing of| to | 17,

| | | armi-| Nov. |1919.

| | |stice.| 11, |

| | | |1918. |

------------------------+------------------------+------+------+------+------

75-mm. gun carriage, |{Rock Island Arsenal | 472| 159| }| { 185

model 1916 |{Bethlehem Steel Co. | 455| 14| } 34| { 25

|{New York Air Brake Co. | 400| 33| }| { 97

| | | | |

75-mm. gun carriage |Willys-Overland Co. | 2,927| 291| | 1,299

| | | | |

75-mm. gun carriage |Bethlehem Steel Co. | 2,868| 724| 124| 921

| | | | |

75-mm. gun carriage | do. | 968| 439| | 1,010

| | | | |

75-mm. gun carriage |{ do. | 436| 436| | 441

limber, model 1918 |{American Car & Foundry | 3,661| 3,661| 980| 3,661

|Co. | | | |

| | | | |

75-mm. gun caisson, |{Bethlehem Steel Co. | 1,666| 302| 4,957| 831

model 1918 |{American Car & Foundry |20,356|11,680| |18,301

|Co. | | | |

| | | | |

75-mm. caisson limber, |{Bethlehem Steel Co. | 1,916| 1,210| | 1,916

model 1918 |{American Car & Foundry |20,675|15,526| 4,126|20,675

|Co. | | | |

| | | | |

|{Symington-Anderson Co. | 640| 416| }| { 416

75-mm. cannon, model |{Wisconsin Gun Co. | 160| 116| } 19| { 116

1916 |{Watervliet Arsenal | 264| 161| }| { 192

|{Bethlehem Steel Co. | 340| 2| }| { 2

| | | | |

75-mm. cannon (French) |{Symington-Anderson Co. | 4,300| 103| | 860

|{Wisconsin Gun Co. | 2,050| 9| | 190

| | | | |

75-mm. cannon (British) |Bethlehem Steel Co. | 2,868| 592| 124| 909

------------------------+------------------------+------+------+------+------

4.7-INCH GUNS.

In the 4.7-inch field gun, model of 1906, America took to France a

weapon all her own. It was a proven gun, too, developed under searching

experiments and tests. There were 60 of these in actual service when

we got into the war. The 4.7-inch guns, with their greater range and

power, promised to be particularly useful for destroying the enemy's

77-millimeter guns.

The carriage model of 1906 for the 4.7-inch gun is of the long recoil

type, the recoil being 70 inches in length. The recoil is checked by a

hydraulic cylinder, and a system of springs thereupon returns the gun

to the firing position. The gun's maximum elevation is 15 degrees, at

which elevation, with a 60-pound projectile, the gun has a range of

7,260 meters, or 4½ miles. With a 45-pound projectile a range of 8,750

meters, or nearly 5½ miles, can be obtained at 15 degrees elevation.

It is possible to increase this range to about 10,000 meters, or well

over 6 miles, by depressing the trail into a hole prepared for it, a

practice often adopted on the field to obtain greater range. The total

weight of the gun carriage with its limber is about 9,800 pounds.

An order for 250 of the 4.7-inch carriages was placed with the Walter

Scott Co., at Plainfield, N. J., July 12, 1917, upon the recommendation

of committees of the Council of National Defense, who were assisting

the Ordnance Department in the selection of industrial firms willing to

accept artillery contracts. Of the 250 ordered from this concern, 49

were delivered up to the signing of the armistice.

The Rock Island Arsenal had also been employed previously in turning

out 4.7-inch carriages; and the capacity of that plant, although

small, was utilized. Under the date of July 23, 1917, the arsenal

was instructed to deliver 183 carriages. Late in December, 1917,

the Studebaker Corporation was given an order for 500. On September

30, 1918, Rock Island Arsenal was given an additional order for 120

carriages, while the Studebaker order was reduced to 380. Additional

plant facilities had to be provided at both the Walter Scott Co. and

the Studebaker Corporation.

Up to December 12, 1918, a total of 381 carriages of the 4.7-inch type

had been completed and delivered. These carriages included the recoil

mechanism. In the month of October, 1918, alone, 113 were produced, and

this rate would have been continued had the armistice not been signed.

Cannon for the 4.7-inch units were turned out at the Watervliet Arsenal

and the Northwestern Ordnance Co., Madison, Wis. Deliveries from the

Watervliet Arsenal began in June, 1918, totaling 120 up to December,

while the Northwestern Ordnance Co., starting its deliveries in August,

had completed 98 by December.

Up to the 15th of November, 64 complete 4.7-inch units had been floated

for our forces overseas.

Forgings for the 4.7-inch gun cannon were made by the Bethlehem Steel

Co. and the Heppenstall Forge & Knife Co., of Pittsburgh, Pa.

Owing to the great difference in cross section between muzzle and

breech end of the jacket, great difficulty was experienced in the heat

treatment of these forgings, particularly on the part of manufacturers

who had had no previous experience in the production of gun forgings.

[Illustration: FRONT AND REAR VIEWS OF OUR 4.7-INCH GUN AND CARRIAGE,

MODEL 1906, WITH WHICH OUR TROOPS HAVE BEEN EQUIPPED FOR A LONG TIME.

This gun throws a projectile weighing 45 pounds a distance of about 6

miles.]

[Illustration: TWO VIEWS OF 155-MILLIMETER GUN, MODEL 1918, G. P. F.

The upper view shows the piece mounted on an auto truck for quick

moving about.]

In order to produce enough forgings to supply the finish-machining

shops, an order for 50 jackets was later given to the Edgewater Steel

Co., of Pittsburgh, Pa., where the jackets were forged. These were

then sent to the Heppenstall Forge & Knife Co. for rough machining and

finally returned to the Edgewater Steel Co. for heat treating. An order

for 150 jackets was also given to the Tacony Ordnance Corporation.

Shortly before the signing of the armistice, the jacket was redesigned

so that the heavy breech end was forged separately in the shape of a

breech ring. This design, however, was not produced.

It was desired to develop a 4.7-inch gun carriage having the

characteristics of the split-trail 75-millimeter gun carriage, model of

1916, so that greater elevation and wide traverse could be obtained.

The Bethlehem Steel Co. was given a small order for 36 carriages of

their own design prior to the war, and their pilot carriage had been

undergoing tests at the proving ground. The design was, however, not

sufficiently advanced to be used in the war.

-----------------------+-----------------------+--------+----------+---------

Unit. | Contractor. | Number | Number | Number

| |ordered.|completed |completed

| | | at the | up to

| | |signing of|April 17,

| | |armistice.| 1919.

-----------------------+-----------------------+--------+----------+---------

4.7-inch gun carriage, |{Rock Island Arsenal | 303| 183| 183

model of 1906 |{Studebaker Corporation| 380| 88| 175

|{Walter Scott Co. | 250| 49| 57

| | | |

4.7-inch gun-carriage |{American Car & | 433| 433| 433

limber |Foundry Co. | | |

|{Maxwell Motor Co. | 479| 82| 250

| | | |

4.7-inch gun caisson |{American Car & | 1,848| 320| 848

|Foundry Co. | | |

|{Ford Motor Co. | 1,001| 106| 400

| | | |

4.7-inch cannon |{Northwestern Gun Co. | | 56|

|{Watervliet Arsenal | | 93|

-----------------------+-----------------------+--------+----------+---------

Sixteen of these units, also 48 which were previously on hand, were

floated for overseas up to November 11, 1918.

THE 5-INCH AND 6-INCH GUN MOUNTS.

In the war emergency America sought to put on the front every pound of

artillery she could acquire from any source whatsoever. Accordingly,

before any of the manufacturing projects were even started, the

Ordnance Department conducted a preparedness inventory of the United

States to see what guns already in existence we might find that could

be improvised for use as mobile artillery in France. The search

discovered a number of heavy cannon that could serve the purpose--part

of them belonging to the Army, these being the guns at our seacoast

fortifications; part belonging to the Navy, in its stores of supplies

for battleships; and part of them being the property of a private

dealer, Francis Bannerman & Son, of New York.

The guns for this improvised use were obtained as follows:

From the Coast Artillery, a branch of the Army, we obtained ninety-five

6-inch guns, 50 calibers in length, and twenty-eight 5-inch guns, 44.6

calibers; from the Navy stores came forty-six 6-inch guns, ranging

from 30 to 50 calibers in length; from Francis Bannerman & Son, thirty

6-inch guns, 30 calibers long. This was a total of 199 weapons of great

destructive power, awaiting only suitable mobile mounts to make them of

valiant service on the western front. It was the task of the Ordnance

Department to take these guns and as swiftly as possible mount them

on field artillery carriages of an improvised type that could be most

quickly built.

Minor changes had to be made on many of the guns obtained in this

manner in order to adapt them for use on field artillery carriages. The

various seacoast guns were retained as they were in length, because

it was planned to return them eventually to the fortifications from

which they had been taken. The Navy guns, all of the 6-inch size, were

shipped to the Watervliet Arsenal to be cut down to a uniform length of

30 calibers.

The need for speed in manufacture demanded that the carriages for

these guns should be of the simplest design consistent with the

ruggedness required for field operations and the accuracy necessary for

effectiveness. When tests of the first carriages produced were made it

was found that requirements had been more than met.

Orders were placed on September 24, 1917, with the Morgan Engineering

Co., of Alliance, Ohio, for 70 mounts for the 6-inch units. A few days

later this number was increased to 74, while on the 28th of September,

1917, the same company was given an order for 18 additional 6-inch

gun mounts and 28 mounts for the 5-inch guns. Orders for limbers were

placed with the same company on December 1.

It was soon discovered that big transport wagons would be required to

carry the long 6-inch seacoast guns separately because of their great

weight. On February 15, 1918, the Morgan Engineering Co. was ordered to

build these necessary transport wagons.

Difficulties in securing skilled labor, necessary materials, and tools

delayed production of these mounts, but the eighteen 6-inch gun mounts

ordered September 28, 1917, were completed in March, 1918, while the

twenty-eight 5-inch gun mounts ordered on the same date were finished

in April. In August, 1918, the seventy-four 6-inch gun mounts were

turned out. The production of an additional order for thirty-seven

6-inch gun mounts was just beginning when the armistice was signed.

The 6-inch gun carriage, bearing the gun, weighs about 41,000 pounds.

A maximum range of over 10 miles can be obtained by this weapon. The

complete 5-inch gun unit weighs about 23,500 pounds and has a maximum

range of more than 9 miles. In understanding the difficulties that

faced the Ordnance Department in building carriages for these guns, it

should be recalled that these big weapons were originally built for

fixed-emplacement duty and were therefore much heavier than mobile

types. This fact complicated the problem of designing the wheeled

mounts. They proved to be more difficult to maneuver than the lighter

types of guns.

--------+---------+----------+------------+------------

| | | Number | Number

| | Number | completed | floated for

Model. | Size. | ordered. | prior to | overseas.

| | | Nov. 11. |

--------+---------+----------+------------+------------

1897 | 5-inch | 28 | 28 | 26

1917 | 6-inch | 74 | 74 | 68

1917-A | 6-inch | 18 | 18 | 4

1917-B | 6-inch | 37 | 1 |

--------+---------+----------+------------+------------

155-MILLIMETER HOWITZERS.

It is a testimonial to the adaptability and skill of American industry

that we were able to duplicate successfully in this country the

celebrated 155-millimeter howitzer, before 1917 built only in the

factory of its original designer, the great firm of Schneider et

Cie., in France. This powerful weapon is a fine example of the French

gun builders' art, in a country where the art of gun-making has been

carried to a perfection unknown anywhere else.

The 155-millimeter howitzer's history dates back to the nineteenth

century. In its development the French designers had so strengthened

its structure, increased its range, and improved its general

serviceability, that in 1914 it was ready to take its place as one of

the two most-used and best-known weapons of the allies, the other being

the 75-millimeter field gun.

As thus perfected the howitzer weighs less than 4 tons and is extremely

mobile for a weapon of its size. It can hurl a 95-pound projectile

well over 7 miles and fire several times a minute. The rapidity of

fire is made possible by a hydropneumatic recoil system that supports

the short barrel of the gun and stores up the energy of the recoil by

the compression of air. With the gun pointing upward at an angle of 45

degrees, the recoil mechanism will restore it into battery in less than

13 seconds. The carriage of the gun is extremely light, being built of

pressed steel parts that incorporate many ingenious features of design

to reduce the weight. The shell and the propelling charge of powder are

loaded separately.

The American-built 155-millimeter howitzer was practically identical

with that built in France. Any of the important parts of the American

weapon would interchange with those which had come from the Schneider

factory. We equipped the wheels of our field carriage, however, with

rubber tires, and gave the gun a straight shield of armor plate instead

of a curved shield.

In the spring of 1917 we bought the plans of the howitzer from

Schneider et Cie. and began at once the work of translating the

specifications into American measurements. This work monopolized the

efforts of an expert staff until October 8, 1917.

In order to facilitate the reproduction here, we divided the weapon, as

a manufacturing proposition, into three groups--the cannon itself, the

carriage, and the recuperator or recoil system--and placed each group

in the hands of separate contractors. There was, of course, the usual

difficulty in finding manufacturers willing to undertake production of

such an intricate device and who also possessed machine shops that had

the equipment and talent required for such work, and in procuring for

these shops the highly specialized machinery that would be necessary.

The American Brake Shoe & Foundry Co., of Erie, Pa., whose magnificent

work in building a special plant has been described in the preceding

chapter, took an order in August, 1917, for 3,000 howitzer cannon and

by October, 1918, was producing 12 of them every day. The company

turned out its first cannon in February, 1918, approximately six months

after receiving the contract, having in the interim built and equipped

a most elaborate plant. It is doubtful if the annals of industry in any

country can produce a feat to match this.

In fact, the production of cannon by the Erie concern so outstripped

the manufacture of carriages and other important parts for the howitzer

that it was possible by September, 1918, for us to sell 550 howitzer

bodies to the French Government. When the armistice was signed on

November 11, 1918, the company had completed 1,172 cannon.

In November, 1917, we placed orders for 2,469 carriages for this

weapon, splitting the order between the Osgood-Bradley Car Co., of

Worcester, Mass., and the Mosler Safe Co., of Hamilton, Ohio. Then

followed a long battle to secure the tools and equipment, the skilled

mechanical labor, and the necessary quantities of the best grades of

steel and bronze, an effort in which the contracting companies were

at all times aided by the engineers of the Ordnance Department. All

obstacles were overcome and the first carriages were ready for testing

in June, 1918. When the armistice was signed 154 carriages had been

delivered, and production was moving so rapidly that one month later

this number had been run up to 230.

The limbers were manufactured by the Maxwell Motor Car Co., which had

orders to turn out 2,575 of them. The first deliveries of limbers came

in September, 1918, and seven a day were being turned out in October, a

total of 273 having been completed by the day of the armistice. A month

later the number of completed limbers totaled 587.

It was in the making of the recuperator systems that the greatest

problems were presented. No mechanism at all similar to this had ever

been made in this country. No plant was in existence here capable of

turning out such a highly complicated, precise, and delicate device.

Finally, after much Governmental search and long negotiation, the

Dodge Bros., of Detroit, motor car builders, agreed to accept the

responsibility. In this effort they built and equipped the splendid

factory, costing $10,000,000, described elsewhere.

This howitzer recuperator is turned out from a solid forging, weighing

3,875 pounds, but the completed recuperator weighs only 870 pounds.

Each cylinder must be bored, ground, and lapped to a degree of fineness

and accuracy that requires the most painstaking care.

Difficulties of almost every sort were experienced with the forgings

and other elements of the recuperators. The steel was analyzed and its

metallurgical formulas were changed. The work of machining proceeded

favorably until the very last operation--that of polishing the interior

of the long bores to a mirrorlike glaze and still retaining the extreme

accuracy necessary to prevent the leakage of oil past the pistons. Such

precision had been theretofore unknown in American heavy manufacture.

Until the many processes could be perfected, the deliveries were held

back.

Even with the delivery of the first recuperator, difficulties did not

vanish. This mechanism has no adjustments which can be made on the

field, but depends for its wonderful operation upon the extreme nicety

of the relation of its parts. It required the alteration of certain

small parts before the first trial models could be made to function.

However, all obstacles and difficulties were finally overcome, and

in the plant that had been erected during the bitter cold of one of

our severest winters, and with practically entirely new machinery

and workmen, production got under way, and the first recuperator was

delivered early in July, 1918, nine months after the contract was

signed. Production in quantity began to follow shortly after that

month, and by November an average of 16 recuperators a day was being

turned out. Of the 3,120 recuperators contracted for, 898 had been

finished when the armistice was signed, and this quantity was increased

to 1,238 one month later.

The steel required for the recuperators in these 155-millimeter

howitzers, and also for those of the 155-millimeter guns, was of

special composition; yet all the forge capacity in this country was

being utilized in other war manufacture. New facilities for the

manufacture of these forgings had to be developed by increasing the

capacity of the Mesta Machine Co. of Pittsburgh, until it could meet

our requirements. The Government itself contracted for these forgings

and supplied them to Dodge Bros.

Each howitzer required some 200 items of miscellaneous equipment, such

as air and liquid pumps and other tools. These were purchased from many

sources, and many of these contractors had just as much difficulty

with the small parts as the larger firms had with the more important

sections of the howitzers.

Many of the problems involved in turning out the complete unit

could not be known or understood until they were met with in actual

manufacture. Mechanical experts representing Schneider et Cie. were on

hand at all times to help solve difficulties as they arose.

The Government turned to France for an auxiliary supply of carriages

for the American-built howitzers, placing orders for 1,361 with French

concerns. Of this number 772 had been completed when the armistice was

signed, and the French expected soon to turn out the carriages at the

rate of 140 per month. It might also be noted here that we placed an

order in England for 302 British 6-inch howitzers, a piece very like

the French howitzer. The British contract was to be completed April 1,

1919.

The various parts of the 155-millimeter howitzer were assembled into

complete units and tested at the Aberdeen Proving Grounds. After being

assembled and tested, the whole unit was taken apart and packed into

crates especially designed for overseas shipment. One crate held two

howitzer carriages with recuperators in less space than would have been

occupied by one carriage on its wheels.

It will be noted that the first gun body of the 155-millimeter

howitzers made in this country was delivered in February and the first

recuperator in July. Before the recuperators were ready, the other

parts of the howitzer had been proof-tried by using a recuperator of

French manufacture.

During the months of August and September, 1918, the first regiment

equipped with 155-millimeter howitzers was made ready at Aberdeen. The

big weapons were packed and on the dock for shipment overseas when the

armistice was signed. These first ones were to be followed by a steady

stream of howitzers. All arrangements had been made to assemble units

and crate them for overseas at the Erie Proving Ground at Port Clinton,

Ohio.

None of the 155-millimeter howitzers built here reached the American

Expeditionary Forces, but French deliveries of the weapon up to the

signing of the armistice totaled 747.

------------------------+------------------------+--------+---------+---------

Unit. | Contractor. | Number | Number | Number

| |ordered.|completed|completed

| | |Nov. 11, |Apr. 17,

| | | 1918. | 1919.

------------------------+------------------------+--------+---------+---------

155-mm. howitzer |Osgood Bradley Car Co. | 900| 136| 369

carriage | | | |

| | | |

155-mm. carriage | do. | 49| | 0

replacement parts | | | |

| | | |

155-mm. howitzer | do. | 250| | 93

carriage | | | |

| | | |

Do |American Rolling Mill | 1,270| 18| 26

|Co. (old Mosler Safe | | |

|contract) | | |

| | | |

Do |Rock Island Arsenal | 172| | 0

| | | |

155-mm. howitzer | | | |

carriage limbers |Maxwell Motor Co. | 2,575| 273| 700

| | | |

Do |Rock Island Arsenal | 100| | 0

| | | |

155-mm. howitzer caisson|Ford Motor Co. | 8,937| 4,373| 8,937

| | | |

155-mm. howitzer cannon |American Brake Shoe & | | |

|Foundry Co. | | 1,172| 1,789

------------------------+------------------------+--------+---------+---------

THE 155-MILLIMETER G. P. F. GUNS.

The reproduction in the United States of the French 155-millimeter G.

P. F. (the French designation) gun presents much the same story as that

of the howitzer of equal size--a story of difficulties in translating

plans, writing into them the precision of finishing measurements that

the French factory usually leaves to the skill of the mechanic himself,

difficulties in finding manufacturers willing to undertake the work,

and then of providing them with suitable raw materials and machinery,

and, above all, of locating the necessary skilled mechanics.

This strange, big monster of a weapon is of rugged design. The entire

unit weighs 19,860 pounds. The gun has the extremely high muzzle

velocity of 2,400 feet per second, a rate of propulsion that throws the

95-pound projectile 17,700 yards, or a little more than 10 miles.

The wheels of the carriage have a double tread of solid rubber tire.

By an ingenious arrangement a caterpillar tread can be applied to the

wheels in a few minutes whenever soft ground is encountered.

The center of gravity of the unit is low. The wheels are of small

dimensions and the cradle is trunnioned behind in such a fashion as

to reduce the height of the cannon. The carriage has a split trail,

which allows for a large clearance for recoil at a high elevation and

a large angle of traverse. The carriage when traveling is supported on

semielliptical springs, as is also the carriage limber.

Two large steel castings make up the carriage of this unit. The bottom

part of the carriage is supported by the axle, which carries the two

sections of the split trail upon the hinge pins. The top part of

the carriage is supported by and revolves upon the bottom carriage

and carries in trunnioned bearings the recuperator. The principal

difficulty in carriage manufacture was to obtain in this country the

extremely large steel castings of light-section, high-grade steel.

The carriages, 1,388 in number, were ordered in November, 1917, from

the Minneapolis Steel & Machinery Co. The first delivery of carriages

was made in August, 1918, and in the last week of October they were

being turned out at the rate of seven a day. Up to the armistice date

370 had been produced, of which 16 had been sent overseas.

We also placed orders in France for 577 of these carriages, of which

216 had been completed upon the signing of the armistice. The American

monthly rate of production of carriages in October was 162.

The 155-millimeter gun itself is far from being simple to manufacture.

It is of considerable length and is built of a number of jackets and

hoops to give the required resistance to the heavy pressures exerted

in firing, this being a high-velocity gun. Except for a slight change

in the manner of locking the hoops to the jacket, our gun is identical

with that of the French.

Orders for 2,160 cannon were given to the Watervliet Arsenal and the

Bullard Engineering Works, at Bridgeport, Conn., in November, 1917.

The Bullard Engineering Works had to construct new buildings and to

purchase and install special equipment, and the Watervliet Arsenal

had to extend its shops and also purchase and install much additional

machinery--a job that took time at both places.

The first deliveries of cannon came from Watervliet Arsenal in July,

1918. During October 50 cannon were delivered, and it seemed certain

that by early in 1919 the projected eight cannon per day would be the

rate attained. We shipped 16 of the cannon overseas. By November 11 we

had received 71 cannon, a number increased to 109 by December 12.

Limbers in the same quantity as carriages were ordered from the

Minneapolis Steel & Machinery Co., which produced a limber to accompany

each one of its delivered carriages. This limber has an extremely heavy

axle, similar to the automobile front axle. Its size and weight caused

difficulty in obtaining it as a drop forging.

To Dodge Bros. was assigned the task of producing the recuperators for

this gun in their special plant. The 155-millimeter gun recuperators,

however, were made secondary to the production of the recuperators for

the 155-millimeter howitzers, which were the easier of the two sorts to

build.

Forgings were available and work started on recuperators in April,

1918. No rapid completion of these intricate mechanisms was possible,

however, as the first forgings encountered many delays in their

machinings. In the cycle of operations, with everything speeded up

to the limit, more than three months must elapse from the day the

recuperator forging is received to the day when the completed mechanism

can be turned over to the inspector as an assembled article.

[Illustration: 155-MILLIMETER HOWITZER, MODEL 1918 (SCHNEIDER).

This weapon throws shell or shrapnel weighing 95 pounds. Muzzle

velocity for shell is 1,420 feet per second. The weight of the howitzer

and carriage is 7,600 pounds.]

[Illustration: 8-INCH HOWITZER, MODEL 1917.]

It was in October, 1918, that the first 155-millimeter gun recuperator

was delivered. The factory expected to reach a maximum capacity of 10

a day. The company built 12 more by December 1. After the armistice

was signed the company's order was reduced to 880, which had all been

completed by May 1, 1919.

In order to have recuperators available for use for the units shipped

from the United States minus these mechanisms, 110 rough-machined

recuperator forgings were shipped to France, where the work of

machining and completing was done.

The translation of the French plans for this weapon furnished one

of the most difficult pieces of work undertaken by the Ordnance

Department. Without counting in the gun pieces, the carriage and

limber is made up of 479 pieces, while the recoil mechanism itself has

372 pieces. A total of 150 mechanical tracings had to be made by our

draftsmen for the carriage and test tools; 50 for the carriage limbers;

142 for the recoil mechanism; 74 for the tools and accessories; or a

total of 416. It was extremely difficult to secure draftsmen who could

do this work, and the translation, accomplished in a few weeks, is

regarded as a remarkable achievement.

The cannon for this gun were tested at the Erie Proving Grounds and

there packed for overseas shipment. We had many cannon and carriages

awaiting shipment when the armistice was signed, the plan being to send

them to France, where they would be equipped with recuperators.

--------------------+------------------+--------+---------+----------+--------

| |ordered.|Nov. 11, | Apr. 17, |Nov. 11,

| | | 1918. | 1919. | 1918.

--------------------+------------------+--------+---------+----------+--------

155-mm. gun carriage|Minneapolis Steel | 1,446 | 370 | 800 | 16

| | | | |

155-mm. gun carriage| do. | 1,446 | 370 | 800 | 16

| | | | |

155-mm. gun cannon |Bullard Engine | 1,400 | 53 | 250 |}

proper | Works | | | |} 16

Do |Watervliet Arsenal| 760 | 18 | 68 |}

--------------------+------------------+--------+---------+----------+--------

8-INCH HOWITZERS

In the early days of the war the British designed an 8-inch field

howitzer that proved itself on battle fields in France. Great Britain

loaded her own plants with orders for this weapon and then turned

to the United States for additional facilities. The Midvale Steel &

Ordnance Co. at Nicetown, Pa., was manufacturing this unit for the

British at the time we entered the war.

On April 14, 1917, exactly eight days after we had formally announced

our purpose of warring with Germany, an order for 80 of these 8-inch

howitzers was placed with the Midvale Steel Co. It was understood

that production on our order was to be begun upon the completion of

the British contract on which the Midvale Co. was then engaged. The

order included the complete units, with carriages, limbers, tools, and

accessories, all to be built in accordance with British specifications.

Contracts for the trails were sublet by the Midvale Co. to the Cambria

Steel Co; for the wheels, to the American Road & Machinery Co.; for the

limbers and firing platforms, to the J. G. Brill Co.; and for the open

sights, to the British-American Manufacturing Co. Panoramic sights for

these guns were furnished by the Frankford Arsenal.

So satisfactory did the production proceed that on December 13, 1917,

the first of the 8-inch howitzers was proof-tried with good results.

Early in January, 1918, the complete units began to come through at the

rate of three a week, increasing to four a week in April and to six a

week in May.

A subsequent contract with Midvale brought the total number of

howitzers ordered from that plant up to 195. These weapons, all of

the model known as the Mark VI, were all produced and accepted before

the signing of the armistice, 96 of them being shipped overseas, with

their full complement of accessories. Each completed unit cost in the

neighborhood of $55,000. These weapons throw a 200-pound projectile

11,750 yards.

The progress of the war moved so swiftly, however, that there soon

was need for artillery units of this same size but with longer range.

Accordingly, a new design, known as the Mark VIII½, was brought out,

having a range of over 13,000 yards. On October 2, 1918, we placed with

the Midvale Co. an order for 100 of these 8-inch howitzers, specifying

carriages of the new, heavier type.

When we entered the war the Bethlehem Steel Co., at Bethlehem, Pa.,

was producing for the British Government a howitzer with a bore of 9.2

inches. The Bethlehem Co. expected to complete these British contracts

in July, 1917. The 9.2-inch howitzer was approximately the same size

as the 240-millimeter howitzer which we were getting ready to put

into production. However, in our desire to utilize every bit of the

production facilities of the country, we ordered 100 of the 9.2-inch

howitzer units from the Bethlehem Steel Co. and placed additional

orders for 132 of these units in England. The British concerns

delivered 40 howitzers before the armistice was signed.

-----------+------------+------------+--------+---------+--------+---------

| | | | 1918. | |17, 1919.

-----------+------------+------------+--------+---------+--------+---------

VI |8-inch |Midvale | 195 | 167 | 96 | 195

VIII½ | do. | do. | 100 | | | 34

-----------+------------+------------+--------+---------+--------+---------

[Illustration: THE 9.2-INCH HOWITZER, MODEL 1917.

This gun shoots shell weighing 290 pounds 8,690 meters. The weight of

the howitzer and carriage is 29,100 pounds.]

[Illustration: TWO VIEWS OF THE 240-MILLIMETER HOWITZER, MODEL 1918.]

THE 240-MILLIMETER HOWITZERS.

The scheme of production of the French 240-millimeter howitzers

was entirely aimed at the year 1919; since even if American heavy

manufacturing establishments had not been loaded with war orders, it

would have been well-nigh impossible to turn out this mighty engine of

destruction in quantities in any shorter period of time.

Although approximately the same size as the British 9.2-inch howitzer

(the exact diameter of the bore of the 240 being 9.45 inches) and only

a little larger than the 8-inch howitzer, the French gun was far more

powerful than either. The 8-inch and the 9.2-inch howitzers had ranges

in the neighborhood of 6 miles, while their shell weighed from 200 to

290 pounds. The 240, on the other hand, hurled a shell weighing 356

pounds and carrying a bursting charge of between 45 and 50 pounds of

high explosive. Its range was almost 10 miles.

We produced the 8-inch and the 9.2-inch howitzers to fill the gap

during the two years which must elapse before we could get into

quantity production of the 240. The French and British governments in

the fall of 1917 asserted their ability to equip our first 30 combat

divisions in 1918 with heavy howitzers, so that if our production came

along in the spring of 1919 it could meet the requirements of the war

situation.

Consequently we planned to equip our first army of 30 divisions with

8-inch and 9.2-inch howitzers in equal numbers of each. Our second

army of 30 divisions should be wholly equipped with 240-millimeter

howitzers; and our expected production of these, being beyond our own

contemplated needs, would serve to replace such 8-inch and 9.2-inch

howitzers as had been lost in the meantime.

As we adapted it from the French Schneider model, the 240-millimeter

howitzer consisted of four main parts--the howitzer barrel, the

top carriage, the cradle with recoil and mechanism, and the firing

platform. Each of these four parts had its own transportation wagon and

limber drawn by a 10-ton tractor. The weapon was set up with the aid of

an erecting frame and a small hand crane.

Each of the main sections is composed of numerous smaller assembled

parts made up of various grades of iron and steel and raw materials,

all requiring the greatest precision in their manufacture and all

having to pass rigid and exacting tests for strength and dimensions.

The production of even one of these enormous weapons would have been

a hard job for any American industrial plant, but to manufacture over

1,200 of them, and that within the comparatively limited time allowed

and under the abnormal industrial and transportation conditions then

prevailing, was a task of tremendous difficulty and complexity.

On September 1, 1917, an order was placed with the Watertown Arsenal

for 250 carriages for the American 240's, to be turned out complete

with the recoil mechanism, transportation vehicles, tools, and

accessories. To show the size of the job, an allotment of $17,450,000

was set aside to cover the estimated expenses at the arsenal.

Well equipped as the Watertown Arsenal was said to be at the time for

the production of heavy gun carriages, it was found necessary, in

order to handle this job, to construct a new erecting shop that had a

capacity practically as large as all the other buildings of the plant

put together. The number of employees at the arsenal was increased from

1,200 to more than 3,000.

The greatest difficulty experienced was in obtaining the large number

of heavy machine tools required, and experts were sent out to scour

the country in an effort to locate these tools wherever they might

be available. Raw materials could not be procured in sufficient

quantities, while numerous transportation delays impeded the work.

Finally, in October, 1918, the pilot carriage was completed and

sufficient progress had been made on the entire contract to assure

production of the required number of units in the early part of 1919.

A second carriage contract (Nov. 16, 1917) went to the Standard Steel

Car Co., of Hammond, Ind. This called for the delivery of 964 carriages

complete with transportation vehicles, limbers, tools, etc., but not

with recuperators. These the Otis Elevator Co., of New York, undertook

to deliver.

The Standard Steel Car Co. is one of the most important builders of

railway cars, freight and passenger, in the country, and it possessed a

large and well-equipped plant. Nevertheless, the company was compelled

to construct several additional buildings and practically to double the

capacity of its huge erecting shop in order to prepare adequately for

the tremendous task undertaken.

As a means to save time, subcontracts were immediately placed with more

than 100 firms throughout the East and Middle West for the production

and machining of as many as possible of the component parts needed by

the Standard Steel Car Co. Wherever practicable, the subcontractors

working on similar contracts for the Watertown Arsenal were retained

by the Indiana company, so that better prices might be obtained, parts

standardized, and the whole production greatly facilitated.

Once the work was well under way the ramifications of this one

contract, with its subcontracts for parts, materials, tools, building

construction, etc., extended throughout practically the entire

industrial facilities of the eastern and central sections of the

country.

As in the case of the contract given the Watertown Arsenal, there were

many difficulties in obtaining tools and raw materials. In a large

majority of cases allocations, partly of iron and steel products, had

to be obtained through the War Industries Board. When allocations had

been granted, priority orders had to be secured, as the producers of

these materials were already overworked with Government orders of

varying importance.

With the pilot carriage complete in the early part of October,

production on all the main parts had progressed by November to such

an extent that a large output of finished carriages was assured

for December and thereafter, had not the signing of the armistice

intervened and ended the necessity for further expedition of the work.

Orders for howitzer bodies were placed as follows:

Sets.

Bethlehem Steel Co., Nov. 21, 1917. 237

Edgewater Steel Co., Oct. 24, 1917. 175

Tacony Ordnance Corporation, Nov. 14, 1917. 175

Watertown Arsenal, Nov. 10, 1917. 80

American Bridge Co., Mar. 31, 1918. 800

The Watervliet Arsenal on November 20, 1917, was instructed to do

the machining of forgings so as to turn out 250 gun bodies for the

240-millimeter howitzers, and three months later this order was

doubled. On November 7, 1918, an additional 660 were ordered from

Watervliet, making a grand total of 1,160 howitzer cannon of this

caliber ordered machined and completed at the Watervliet Arsenal. The

arsenal contracted to reach an output of 100 cannon a month and deliver

the last of the 1,160 not later than September 30, 1919.

It was found necessary to erect an entirely new shop for the machining

of these howitzers. This shop was completed in May, 1918. During the

war period $13,164,706 was spent or allotted to the Watervliet Arsenal

for increasing its facilities. Forgings were furnished to the arsenal

by the Government, but the forging situation was never a delaying

factor in the production of 240-millimeter howitzers.

In all, 158 sets, of 1,467 ordered, were delivered up to December 12,

1918. The pilot howitzer was delivered by the Watervliet Arsenal to the

proving ground on August 24, 1918.

In the summer of 1918 the Watertown Arsenal contracted to build 252

additional recuperators for these howitzers. Work was started at once

in the shops, and, though additional facilities had to be prepared and

much new equipment added, the production of the first recuperator was

begun without delay. It was found that the planing equipment at the

arsenal was not sufficient to handle the work, and therefore a great

deal of the rough planing was done by subcontractors.

The Watertown Arsenal was to furnish its own forgings, but it was

quickly found that an additional source of supplies was required.

The Carnegie Steel Co. had been given an order on December 27, 1917,

for 1,300 recuperator forgings, and some of these were sent to the

Watertown Arsenal.

The first recuperator was completed October 28, 1918, and 16 had been

finished up to December 31, 1918, when 280 forgings were in the process

of machining.

To handle its order for 1,039 recuperators, the Otis Elevator Co.,

of New York, found it necessary to rebuild a plant which it owned in

Chicago. Forgings were furnished by the Government.

On May 1, 1918, the Otis Elevator Co. started its rough machining.

Hard spots were found in the metal, causing great trouble at first,

but this difficulty was overcome by changes in the heat treatment. The

Carnegie Steel Co. was then instructed to rough-machine the forgings

before sending them to the Otis Elevator Co. An order was also given to

the Midvale Steel Co. to rough-machine 24 forgings. Early in November,

1918, the Otis Elevator Co. finished its first recuperator.

One 240-millimeter howitzer unit was completed at the time of the

signing of the armistice, out of a total of 1,214 contracted for;

but had war conditions continued, the expectation was for a monthly

capacity of 80 units by 1919. Actual deliveries are given below:

--------------------+-------------------+--------+---------+---------

| | |Number |Number

Units. | Contractors. |Number |completed|completed

| |ordered.|Nov. 11, |Apr. 17,

| | |1918. |1919.

--------------------+-------------------+--------+---------+---------

240-mm. unit, |} Watertown | 250 |{ [11]1 | [11]41

complete, except |} Arsenal | |{ [12]4 | [12]25

howitzer |} | | |

240-mm. howitzer | Standard | 964 | 5 | 67

carriage units, | Steel Car Co. | | |

except recuperators | | | |

Windlasses | Dodge | 1,125 | 33 | 350

| Manufacturing Co | | |

Rammer trucks | do. | 1,205 | 2 | 375

Shot trucks | do. | 3,214 | 2 | 1,000

240-mm. howitzer | Watervliet | | 2 | 19

cannon | Arsenal | | |

--------------------+-------------------+--------+---------+---------

[11] Carriage alone.

[12] Carriages with recuperators.

FIGHTING THE AIRPLANE WITH ARTILLERY.

The American development of antiaircraft artillery had, previously to

1917, been confined almost exclusively to the task of designing and

constructing stationary units of defense for our coast fortifications.

It was naturally expected that it would be at those points that we

would first, if ever, have to meet an attack from the air. Very little

attention had been paid mobile artillery of this sort.

Before April, 1916, the Ordnance Department had designed a high-powered

3-inch antiaircraft mount for the fixed emplacement at coast

fortifications. The gun on this mount fired a 15-pound projectile with

a muzzle velocity of 2,600 feet a second. It is still to-day the most

powerful antiaircraft weapon of its caliber. Between May, 1916, and

June 18, 1917, orders for 160 of these mounts were placed with the

Watertown Arsenal and the Bethlehem Steel Co. Up to April 10, 1919, a

total of 116 of these had been completed and sent for emplacement at

the points selected.

[Illustration: TWO VIEWS OF ANTIAIRCRAFT GUNS ON TRUCK MOUNTS.]

[Illustration: TWO OTHER VIEWS OF ANTIAIRCRAFT GUNS.]

By the end of 1916, however, it was foreseen that it would be necessary

to provide antiaircraft artillery of a mobile type as part of the

equipment for any field forces that might be sent abroad. Since that

contingency seemed entirely possible at that time, and as it appeared

to be impossible to provide a suitable design that would have a

sufficient period of time in which to get proper consideration and

test, it was decided to improvise a simple structural steel design that

would permit quick construction and on which a 75-millimeter field gun,

that was already in production, could be mounted.

This design was completed May 1, 1917, and an order for 50 placed with

the Builders Iron Foundry. Deliveries on these were made during the

fall of 1917, and the carriages were at once shipped to France for

equipment with French field guns and recuperators that had been already

procured for the purpose.

In its mobility the improvised antiaircraft gun mount was far from

perfect. It was necessary to disassemble it partly and mount it on

trailers. The need for a mount that could be moved easily and speedily

had been realized before our entrance in the war, and a design

embodying these qualities was completed as early as December, 1916.

This truck was designed to be equipped with the American 75-millimeter

field gun, model of 1916. Before the drawings were completed an order

for the pilot mounts of this type was placed with the Rock Island

Arsenal. The war came on, and it was decided not to wait for a test

of the mounts before starting general manufacture. Accordingly the

New Britain Machine Co., in July, 1917, was given an order for 51

carriages. No further orders were placed for carriages of this sort, as

it was not thought best to go too heavily into production of an untried

mount.

It may be noted here that our first 26 antiaircraft guns were mounted

on White 1½-ton trucks.

It was also realized that the field guns with which these mounts were

to be equipped did not have the power and range that the war experience

was showing to be necessary. The only reasons that the field guns of

the 75-millimeter caliber were used in this way was because they were

the guns most quickly available and because the French were already

using them for this purpose.

To meet the need of more powerful antiaircraft weapons, a need becoming

more pressing each day, a 3-inch high-powered antiaircraft gun was

designed and mounted on a four-wheel trailer of the automobile type.

This mount permitted elevations of the gun from 10 degrees to 85

degrees and also allowed for "all around" firing. An order for 612 of

these carriages was given to the New Britain Machine Co. in July, 1917,

shortly after the contract for the 51 truck mounts had been placed with

that concern.

Because of the urgency of the situation it was necessary to construct

these carriages without the preliminary tests on a pilot carriage.

This, of course, is a very undesirable practice, but under the existing

conditions no other procedure would have been practicable. The French

antiaircraft auto truck mount, which had the French 75-millimeter field

gun with its recuperator placed upon a special antiaircraft mount, was

not adopted at the time, because, in July, 1917, the whole question of

the possibility of constructing French recuperators in this country was

still entirely unsettled. It was imperative then that we develop our

own designs.

All of the 51 truck mounts for the antiaircraft guns were delivered

during the fall and early winter of 1918, and 22 of them were in France

before December, 1918.

Delivery of the first carriage for the 3-inch high-powered gun mounted

on the trailer carriage was made in August, 1917. It had been rushed

ahead of general production in order to be given some sort of a test.

No further deliveries were made, but manufacture reached a point where

production in quantity could begin.

A representative of the Ordnance Department was sent to France and

England in December, 1917, to gather all the information possible

on antiaircraft artillery. As a result of his investigations it was

determined that it would be best to procure the greater part of our

fire-control equipment in France, since the instruments developed there

were in some cases of a highly complicated nature and their manufacture

entirely controlled by private parties. Orders were placed for enough

of these instruments for the equipment of the first 125 batteries.

Meanwhile, fire-control instruments of various types were in the

process of development in this country; but, as they were largely

based upon theoretical construction derived from study of the French

practices, it was deemed best not to manufacture any of these

instruments in quantity, as better instruments of French design were

available. Drawings of the French instruments were brought back by the

Ordnance officer on his visit to France and were available in this

country in the spring of 1918, when manufacture of some of them began

in the United States.

At the signing of the armistice our forces in France were equipped

almost wholly with antiaircraft artillery loaned to us and supplied

by the French. This, of course, does not include the 101 improvised

and truck mounts completed during 1917. Production here, however, had

reached such a point that shipment of material would have begun in

quantity in January, 1919.

The estimated requirements of antiaircraft artillery for 2,000,000 men

in 48 divisions is only 120 guns. Other material, of course, would

have been required previously for defense of depots, railheads, etc.,

dependent in a great measure upon the activities of German bombers. It

is estimated that about 200 guns would have sufficed for this purpose.

To summarize, 50 of the so-called improvised 75-millimeter antiaircraft

guns and mounts had been ordered and completed up to the time of the

signing of the armistice; 51 of the 75-millimeter antiaircraft mounts,

model of 1917, had been ordered and 46 completed; while 612 of the

3-inch antiaircraft trailer carriage mounts, model of 1917, had been

ordered, of which 1 had been actually delivered at the signing of the

armistice, the balance to come at the rate of 26 per month starting in

December.

_Artillery--Production of complete units, by months._

[Deliveries in the United States on U. S. Army orders only.]

-----------------------+-----+------------------------------

| To | 1918

|Jan.,+----+----+----+----+----+-----

|1918.|Jan.|Feb.|Mar.|Apr.|May.|June.

-----------------------+-----+----+----+----+----+----+-----

75-mm. gun, model 1897 | 0 | 0 | 0 | 0 | 0 | 0 | 0

75-mm. gun, model 1916 | 0 | 0 | 0 | 9 | 4 | 6 | 21

75-mm. gun, model 1917 | 1 | 11 | 36 | 28 | 58 | 22 | 61

75-mm. antiaircraft gun| 0 | 49 | 2 | 0 | 0 | 1 | 1

3-inch antiaircraft gun| 0 | 0 | 0 | 0 | 0 | 0 | 0

4.7-inch gun | 0 | 0 | 0 | 0 | 0 | 0 | 0

155-mm. howitzer | 0 | 0 | 0 | 0 | 0 | 0 | 0

5-inch seacoast gun | 0 | 0 | 1 | 27 |[13]|[13]| [13]

6-inch seacoast gun | 0 | 0 | 12 | 5 | 2 | 45 | 23

155-mm. gun | 0 | 0 | 0 | 0 | 0 | 0 | 0

8-inch howitzer | 7 | 12 | 17 | 20 | 22 | 2 | 0

9.2-inch howitzer[14] | 0 | 0 | 0 | 0 | 0 | 0 | 0

240-mm. howitzer | 0 | 0 | 0 | 0 | 0 | 0 | 0

8-inch seacoast gun | 0 | 0 | 0 | 0 | 0 | 0 | 0

10-inch seacoast gun | 0 | 0 | 0 | 0 | 0 | 0 | 0

12-inch gun | 0 | 0 | 0 | 0 | 0 | 0 | 0

12-inch seacoast mortar| 0 | 0 | 0 | 0 | 0 | 0 | 0

-----------------------+-----+----+----+----+----+----+-----

Total | 8 | 72 | 68 | 89 |86 | 76 | 106

-----------------------+-----+----+----+----+----+----+-----

-----------------------+--------------------------------+-----

| 1918 |

+-----+----+-----+----+----+-----+Total.

|July.|Aug.|Sept.|Oct.|Nov.| Dec.|

-----------------------+-----+----+-----+----+----+-----+-----

75-mm. gun, model 1897 | 0 | 0 | 0 | 1 | 0 | 0 | 1

75-mm. gun, model 1916 | 2 | 60 | 42 | 51 | 11 | 45 | 251

75-mm. gun, model 1917 | 61 | 55 | 130 |211 |110 | 55 | 839

75-mm. antiaircraft gun| 2 | 16 | 2 | 18 | 6 | 3 | 100

3-inch antiaircraft gun| 0 | 1 | 0 | 0 | 0 | 0 | 1

4.7-inch gun | 15 | 15 | 28 | 72 | 50 | 44 | 224

155-mm. howitzer | 1 | 8 | 39 | 63 | 65 | 100 | 276

5-inch seacoast gun | [13]|[13]| [13]|[13]|[13]| [13]| 28

6-inch seacoast gun | 4 | 1 | [13]|[13]|[13]| [13]| 92

155-mm. gun | 0 | 0 | 0 | 1 | 5 | 10 | 16

8-inch howitzer | 0 | 23 | 27 | 33 | 13 | 15 | 191

9.2-inch howitzer[14] | 0 | 0 | 0 | 0 | 0 | 0 |[14]0

240-mm. howitzer | 0 | 0 | 0 | 0 | 1 | 0 | 1

8-inch seacoast gun | 0 | 0 | 3 | 14 | 4 | 1 | 22

10-inch seacoast gun | 0 | 0 | 0 | 0 | 0 | 0 | 0

12-inch gun | 0 | 0 | 0 | 0 | 1 | 2 | 3

12-inch seacoast mortar| 0 | 1 | 0 | 0 | 10 | 2 | 13

-----------------------+-----+----+-----+----+----+-----+-----

Total | 85 |180 | 271 |464 |276 |277 |2,058

-----------------------+-----+----+-----+----+----+-----+-----

[13] Project complete.

[14] No deliveries made by Bethlehem Steel Co. on U.S. Army orders

until after signing of the armistice because of priority given to

British orders placed before the American declaration of war.

By "complete units" is meant gun body complete, carriage, and recoil

mechanism or recuperator. Units are given as complete when their

component parts were complete, although the actual assembly of these

parts at a common point, testing, and final delivery usually required

from two weeks' to two months' additional time.

The 5-inch, 6-inch, 10-inch, and 12-inch seacoast guns and the 12-inch

seacoast mortars were taken from the fortifications and modified for

use with mobile carriages, all above 6 inches for railway mounts.

The 75-millimeter gun, model 1897, was the approved model for active

service in France. Model 1916 and model 1917 were used for training

purposes both in the United States and in France.

_Production of mobile artillery (complete units), Apr. 1, 1917,

to Nov. 11, 1918._

[Including all produced for France and Great Britain in United

States.]

------------------------------------------+------------+---------

| Produced. | Shipped

| |Overseas.

------------------------------------------+------------+---------

75-mm. guns (or British 18-pounder) | 970 | 181

3-inch and 75-mm. antiaircraft guns | 97 | [15]26

4.5-inch howitzers | 97 | 97

4.7-inch guns | 157 | 64

155-mm. (5-inch and 6-inch seacoast guns) | 121 |[16]114

155-mm. howitzers | 144 | 0

7-inch guns on caterpillar mounts | [17]10 | 0

Railway artillery | 20 | 11

Heavy howitzers | [18]418 | 322

+------------+---------

Total | 2,034 | 815

------------------------------------------+------------+---------

[15] Does not include 51 improvised mounts for which guns were

furnished by French.

[16] Includes sixteen 155-mm. guns and carriages shipped without

recuperators.

[17] Built for the Marine Corps.

[18] Includes sixteen 8-inch howitzers built for the Marine Corps.

[Illustration: 1½-TON ANTIAIRCRAFT MACHINE GUN TRAILER.]

[Illustration: TWO VIEWS OF THE 7-INCH NAVY RIFLE MOUNTED ON A PEDESTAL

ON A RAILWAY CAR.

This rifle has a range of about 10 miles and throws a projectile

weighing 165 pounds. Note the means of loading and the depression

angle.]