Transcriber’s Notes
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[Illustration: _Faithfully yours_
_Charles T. Porter_]
Engineering Reminiscences
CONTRIBUTED TO
“Power” and “American Machinist”
BY
CHARLES T. PORTER
HONORARY MEMBER OF THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS
_Author of “A Treatise on the Richards Steam-engine Indicator
and the Development and Application of Force in the
Steam-engine,” 1874; “Mechanics and Faith,” 1885_
REVISED AND ENLARGED
_FIRST EDITION_
FIRST THOUSAND
NEW YORK
JOHN WILEY & SONS
LONDON: CHAPMAN & HALL, LIMITED
1908
Copyright 1908
BY
CHARLES T. PORTER
THIS BOOK IS DEDICATED
TO THE MEMORY OF
MY FATHER AND MOTHER
[Illustration: MY FATHER]
[Illustration: MY MOTHER]
PREFACE
A word of explanation seems due to both the reader and myself.
The idea of writing these reminiscences did not originate with me. I
was invited to write them by Mr. F. R. Low, the editor of _Power_. This
invitation I declined, saying that I felt averse to writing a story
in which I must be the central figure. Mr. Low replied that I should
regard it as a duty I owed to the profession. Engineers demanded to
know the origin and early development of the high speed system of steam
engineering. I was the only person who could meet this demand; no one
else possessed the necessary information.
I felt obliged to yield to this view, and can only ask the reader to
imagine that I am writing about somebody else.
C. T. P.
MONTCLAIR, N. J.,
December, 1907.
TABLE OF CONTENTS
CHAPTER I
PAGE
Birth, Parentage and Education. Experience in the Practice of
Law. Introduction to Centrifugal Force. Invention and
Operation of a Stone-dressing Machine 1
CHAPTER II
The Evolution and Manufacture of the Central Counterpoise
Governor. Introduction of Mr. Richards 17
CHAPTER III
Invention and Application of my Marine Governor 34
CHAPTER IV
Engineering Conditions in 1860. I meet Mr. Allen. Mr. Allen’s
Inventions. Analysis of the Allen Link 42
CHAPTER V
Invention of the Richards Indicator. My Purchase of the Patent.
Plan my London Exhibition. Engine Design. Ship Engine Bed to
London, and sail myself 58
CHAPTER VI
Arrival in London. Conditions I found there. Preparations and
Start 65
CHAPTER VII
My London Exhibit, its Success, but what was the matter?
Remarkable Sale of the Engine 71
CHAPTER VIII
Sale of Governors. Visit from Mr. Allen. Operation of the Engine
Sold to Easton, Amos & Sons. Manufacture of the Indicator.
Application on Locomotives 80
CHAPTER IX
Designs of Horizontal Engine Beds. Engine Details. Presentation
of the Indicator at the Newcastle Meeting of the British
Association for the Advancement of Science 93
CHAPTER X
Contract with Ormerod, Grierson & Co. Engine for Evan Leigh, Son
& Co. Engine for the Oporto Exhibition. Getting Home from
Portugal 101
CHAPTER XI
Trouble with the Evan Leigh Engine. Gear Patterns from the
Whitworth Works. First Order for a Governor. Introduction of the
Governor into Cotton Mills. Invention of my Condenser. Failure of
Ormerod, Grierson & Co. 113
CHAPTER XII
Introduction to the Whitworth Works. Sketch of Mr. Whitworth.
Experience in the Whitworth Works. Our Agreement Which was never
Executed. First Engine in England Transmitting Power by a Belt 122
CHAPTER XIII
The French Exposition of 1867. Final Break with Mr. Whitworth 139
CHAPTER XIV
Study of the Action of Reciprocating Parts. Important Help from
Mr. Frederick J. Slade. Paper before Institution of Mechanical
Engineers. Appreciation of Zerah Colburn. The Steam Fire Engine
in England 153
CHAPTER XV
Preparations for Returning to America. Bright Prospects 165
CHAPTER XVI
Return to America. Disappointment. My Shop. The Colt Armory
Engine Designed by Mr. Richards. Appearance of Mr. Goodfellow. My
Surface Plate Work. Formation of a Company 173
CHAPTER XVII
Mr. Allen’s Invention of his Boiler. Exhibition at the Fair of
the American Institute in 1870 190
CHAPTER XVIII
Demonstration to the Judges of Action of Reciprocating Parts.
Explanation of this Action. Mr. Williams’ Instrument for
Exhibiting this Action 198
CHAPTER XIX
Boiler Tests in Exhibition of 1871. We Lose Mr. Allen. Importance
of Having a Business Man as President. Devotion of Mr. Hope 208
CHAPTER XX
Close of the Engine Manufacture in Harlem. My Occupation During a
Three Years’ Suspension 219
CHAPTER XXI
Production of an Original Surface Plate 233
CHAPTER XXII
Efforts to Resume the Manufacture. I Exhibit the Engine to Mr.
Holley. Contract with Mr. Phillips. Sale of Engine to Mr. Peters 238
CHAPTER XXIII
Experience as Member of the Board of Judges at the Philadelphia
Centennial Exhibition 245
CHAPTER XXIV
Engine Building in Newark. Introduction of Harris Tabor 259
CHAPTER XXV
Engine for the Cambria Iron and Steel Company 271
CHAPTER XXVI
My Downward Progress 275
CHAPTER XXVII
My Last Connection with the Company 325
CHAPTER XXVIII
The Fall and Rise of the Southwark Foundry and Machine Company.
Popular Appreciation of the High-speed Engine 331
LIST OF ILLUSTRATIONS
PAGE
1. My First Mechanical Drawing. Longitudinal Section of my Stone-
dressing Machine 7
2. The First Porter Governor 21
3. The Porter Marine Governor 37
4. Porter-Allen Engine. Diagram of Admission--Valve Movements 48
5. Vertical Adjustment of Sustaining Pin for Trunnions of the
Allen Link 52
6. My Improvement in Cranks and Journal Boxes 54
7. My Improvement in Eccentrics 56
8. Diagram from the First Allen Engine taken with the First
Richards Indicator 59
9. Mr. Porter’s Exhibit at the London International Exhibition,
1862 71
10. Diagram from Allen Engine in London Exhibition of 1862 73
11. Spring-testing Instrument Used in the Manufacture of the
Richards Indicator 86
12. Plan of Spring-testing Instrument 89
13. Diagrams from English Locomotives, taken with the Richards
Indicator 91
14. Engine Bed Designed by Mr. Porter 95
15. Cross-head Designed by Mr. Porter 96
16. Connecting-rod and Strap 99
17. Attaching a Steam-drum to a Lancashire Boiler 107
18. Diagrams from Engine of Evan Leigh, Son & Co. 114
19. Condenser and Air-pump Designed by Mr. Porter. (Cross-section) 118
20. Diagrams from Engine Built for Mr. Adams 138
21. Exposition Universelle, Paris, 1867. Diagrams from the “Allen”
Engine Employed in Driving Machinery 142
22. Pair of Diagrams from 18×30 Allen Engine at South Tyne Paper
Mill, 108 Revolutions, Vacuum 28 Inches. Only Half Intended
Load on Engine 160
23. Cross-section of Machine Shop Proposed by Mr. Porter in 1868,
after the Design of Smith & Coventry 168
24. Card from Allen Engine in Colt’s Armory 178
25. Sectional and Front Elevations of One of the Two Pairs of
Porter-Allen Engines in the Colt Armory, Hartford, Conn. 180
26. Sectional and Side Elevations of One of the Two Pairs of
Porter-Allen Engines in the Colt Armory, Hartford, Conn. 181
27. Porter-Allen Engines in the Colt Armory, Hartford, Conn. Front
View 181
28. Porter-Allen Engines in the Colt Armory, Hartford, Conn. Rear
View 181
29. Surface Plates Designed by Mr. Porter 182
30. Diagram from Allen Engine, Back End of Cylinder, at Fair of
American Institute, 1870 194
31. Friction Diagram from Allen Engine at Fair of American
Institute, 1870 196
32. Diagram from Allen Engine, Fair of American Institute, 1870,
Cutting Off at ¹⁄₄ Stroke 196
33. Apparatus for Graphically Showing the Acceleration and
Retardation of the Reciprocating Parts of an Engine 205
34. The Allen Boiler _Facing_ 208
35. The Prototype of the Modern High-speed Engine, Fly-wheel Side 223
36. Prototype of the Modern High-speed Engine, Crank Side 224
37. Longitudinal Section of Cylinder and Valves 225
38. Cross-section of Cylinder and Valves 226
39. Connections of Admission Valves 226
40. First Arrangement of Exhaust Valves 228
41. Main Bearing 230
42. Eccentric and Cross-head and Crank-pin Lubricators 230
43. Surface Plate for Producing a True Plane 234
44. Mr. Porter’s Regulating Valve 244
45. The Corliss Engine Exhibited at the Centennial Exhibition 249
46. Porter-Allen Engine Equal in Power to the Exhibited Corliss
Engine 250
47. Mr. Porter’s Fly-wheel 269
48. Connection of Arms and Rim in Mr. Fritz’ Fly-wheel 273
49. Mr. Allen’s Patent Pressure Plate 293
50. Diagrams from the Otis Engine 311
51. Otis Engine. Dash Pot for Governor 313
52. Diagrams from my First and Only Compound Engine 318
LIST OF FULL-PAGE HALF-TONE PORTRAITS
PAGE
1. CHARLES T. PORTER _Facing title page_
2. MY FATHER _After dedication_
3. MY MOTHER „ „
4. GEORGE T. HOPE 6
5. CHARLES B. RICHARDS, A.D. 1858 26
6. JOHN F. ALLEN 48
7. JOSEPH E. HOLMES 60
8. ALEXANDER GORDON 62
9. WELLINGTON LEE 66
10. CHARLES T. PORTER, A.D. 1862 68
11. FREDERICK E. SICKELS 78
12. W. H. MAW 92
13. WILLIAM J. HOYLE 122
14. SIR JOSEPH WHITWORTH 124
15. FREDERICK J. SLADE 154
16. PROFESSOR CHARLES B. RICHARDS 178
17. PRESIDENT F. A. P. BARNARD 198
18. JOSEPH NASON 204
19. EDWIN F. WILLIAMS 206
20. PROFESSOR ROBERT H. THURSTON 208
21. J. C. HOADLEY 220
22. ALEXANDER LYMAN HOLLEY 238
23. WILLIAM R. JONES 244
24. PROFESSOR FRANCIS REULEAUX 246
25. COLONEL ALEXIS PETROFF 252
26. JAMES MOORE 254
27. EMIL BRUGSCH 256
28. ROBERT W. HUNT 262
29. STEPHEN W. BALDWIN 264
30. HARRIS TABOR 266
31. DANIEL N. JONES 272
32. JOHN FRITZ 274
33. E. D. LEAVITT 308
34. SAMUEL T. WELLMAN 310
35. CHARLES A. OTIS 312
36. DANIEL J. MORRELL 314
37. BENJAMIN F. AVERY 324
38. JAMES C. BROOKS 332
ENGINEERING REMINISCENCES
CHAPTER I
Birth, Parentage and Education. Experience in the Practice of Law.
Introduction to Centrifugal Force. Invention and Operation of a
Stone-dressing Machine.
I was born in Auburn in the State of New York, January 18th, 1826.
My parents were both of New England descent. My father, John Porter,
was born in Hadley, Mass. His father, William Porter, was the son of
Eleazer Porter and his wife Susannah, one of the daughters of Jonathan
Edwards. My father’s mother was Lois Eastman. My mother was born in
Middletown, Conn. Her maiden name was Abigail Phillips. Her ancestry in
the maternal line is traced back to Governors Saltonstall, Dudley and
the two Winthrops.
I graduated at Hamilton College, New York, in 1845, read law in my
father’s office, and in the fall of 1847 was admitted to the bar.
Practiced my profession for six or seven years, first in Rochester,
N.Y., afterwards in New York City.
My knowledge of mechanics may be illustrated by a story I once heard
in England of a man who had been prosecuted for selling adulterated
tobacco. He got off by proving that there was no tobacco at all in
the article that he sold. But this illustration hardly does the case
justice.
I had some mechanical ideas, but they were exactly wrong. For example,
I could not see any difficulty in perpetual motion. All one had to do
was to pump up water, which by its fall would furnish power to run
the pump. This, however, was no more absurd than were two inventions
which were brought out in England while I was there. One of these was
corrugating the faces of the piston, so as to present more extended
surfaces for the steam pressure to be exerted upon. The other was a
device for utilizing that half of the force of the steam which had
been wasted against the cylinder heads. Both of these were published
with commendatory remarks in the _Mechanics’ Magazine_. The last, if
I recollect rightly, was the original bottom feature of the Wells
balance-engine. My error was that I made no account of friction, which
must be overcome before motion can take place. We shall see before long
the same disregard of friction by men who ought to have known better.
My utter ignorance of everything mechanical at that time is capable of
proof. I stepped right into one of those “springes to catch woodcocks”
which were being set in those days, and proved myself to be about as
green a gosling mechanically as ever was plucked.
I had a client by the name of Searle, who was a “dead-beat.” He owed me
about $100, which I could not collect. He finally called upon me and
told me frankly that he could not pay me one red cent, because he had
no money; but he could put me in the way of making a fortune, and he
was anxious in that way to discharge the great obligation which he felt
himself under to me.
A new invention had appeared, called the Gwynne & Sawyer
static-pressure engine, that was bound to revolutionize all
applications of power. It was, he told me, attracting great attention
in engineering circles, and there had been a hot discussion over its
theoretical principles, but its advocates had successfully vanquished
all their antagonists and now the invention was established on a
perfectly sound scientific basis. If I would give him a receipt
in full for the money that he owed me and put another $100 into
this enterprise, he was in a position to secure for me a number of
rights to use the machine. He kindly offered to introduce me to Mr.
Sawyer. Mr. Gwynne was unfortunately absent from home at the time. (I
learned afterwards that he was in jail.) Mr. Sawyer received me most
graciously. I think he had been told by Mr. Searle about how much
taffy I might be expected to swallow, but he must have ventured far
beyond his instructions. He told me that he was delighted to make my
acquaintance; he had frequently heard of me through our mutual friend,
Mr. Searle, and of my triumphs at the bar, and had come to feel a
great admiration for me, and was proud to show this great invention
to a man so eminently capable of appreciating it. He told me that the
invention was a practical method of utilizing that wonderful power
known as centrifugal force. This force could be obtained in any amount.
In fact, it was the force that kept the universe in motion. It had lain
unutilized for so long a time because engineers had never been able
to apply it practically. This difficulty had been completely overcome
in this great invention, and this wonderful power was now to be made
available for the world. He gave me quite an oration on the subject,
saying, “We do not antagonize the forces of nature, we utilize them and
apply them to beneficial purposes; consequently all nature co-operates
with us,” and more to the same effect. He was able to show me a working
model of this great invention; was very sorry that he could not put
it in motion for me that day, as it happened to be a little out of
order; but I would be able to see the principle of its operation very
distinctly. I was flattered into believing that I saw the principle,
with the result that Mr. Sawyer saw the principal, and with the further
result that after that I never saw or heard of either principal or
interest. Our mutual friend, Mr. Searle, also disappeared.
This was my first lesson in mechanics, given to me by a master of his
art. I am not sure, on the whole, but that in one way and another it
has been worth the trifle it cost me.
Had any one at that time told me that the expression “centrifugal
force” is entirely misleading, that in reality there is no such force,
that what goes by this name is not a force at all, nothing but a
resistance, the resistance which a body revolving around an exterior
point opposes to being continually deflected from a straight line of
motion, and which ceases the instant the deflecting force ceases, when
the body merely moves on in a straight line tangent to the circle, and
in bodies revolving around their own axes or centers of gravity is the
same resistance of their atoms, he would probably have had about the
same success in making me see it that I long afterwards had with some
engineering friends.
It is difficult at the present day to conceive the confusion of thought
which then prevailed on this subject. The language of text-books was
vague in the extreme.
The coincidence is not without interest, that my first mechanical
experience, though in this ridiculous fashion, should have been with
what was to become so prominent a feature of the high speed governors
and engine.
I had for some time felt a growing disgust with the profession of the
law. The contrast between the glorious science of human rights and the
art of its practical application was very forcibly presented to my
mind. I realized the fitness of the protest of Bryant, who described
himself as being “forced to drudge for the dregs of men.” I was a
regular reader of the _Evening Post_, in which an article appeared one
day, written by John Bigelow, then the editor of the _Post_, laudatory
of a certain judge whose term on the bench had lately closed, and
who then retired from the profession. On this act Mr. Bigelow warmly
congratulated him. Among a number of pungent expressions in the article
I was particularly struck by this one: “The association of lawyers
is mostly with knaves and fools.” My own experience bore witness to
the truth of this statement. A few legal successes, which cost me
incredible labor, interspersed of course with disappointments, weighed
nothing compared with the daily association which I seemed compelled to
endure. I formed a scheme for establishing a conciliation office for
the amicable settlement of disputes, but found every man prepared to
compromise on the extreme verge of his own position. So I gave that up.
I had another client, a Mr. Hastings, who had invented a stone-dressing
machine, which he had patented, and the patent for which he wanted
to dispose of. He had a working model of his invention, which was
operated for visitors in the shop where it was built. He invited me to
go and see it, which I did, and it certainly worked very well indeed.
I recalled afterwards that the stone was carefully bedded on the table
of the machine. I was quite fascinated with it and took some friends to
see it, who were equally captivated, and the result was that we bought
the patent. To make sure of its value, however, I first called with Mr.
Hastings on Mr. Munn, his patent solicitor, and received Mr. Munn’s
assurance that he had a very high opinion of it.
I gradually abandoned my law business, and devoted myself to the
exploitation of this invention. I put into it all the money I had
and all that I could borrow. After a while a large working machine
was completed for us, the drawings for which I had made by a German
draftsman, and which was built under my direction at the works of Mott
& Ayers, near the foot of West Twenty-sixth Street. When this machine
was finished the parties in interest assembled at these works to see it
tried.
One experiment was enough. I had put into the machine a stone that
was quite a foot thick and which was supported at two points. At the
first cut made across this stone it broke in two in the middle. I
found myself, in the words of President Cleveland, “confronted not by
a theory but by a condition.” The machine was absurd. The patent was
worthless. The enterprise was a failure. Our money had all been thrown
into the sea. Nothing could be done unless I did it; and I knew nothing
of mechanics, of machine design or construction, or of mechanical
drawing, except the little that I had picked up in the works of Mott &
Ayers while this machine was in process of construction. I should say,
however, that the head draftsman in that establishment had given me
some instruction in mechanical drawing, so that I knew the use of the
instruments and what kind of ink to use.
I cannot recollect that I was in the least cast down or discouraged. I
cannot now account for my confidence. I believed that the fundamental
features of this machine were correct. These were: cutting stone by a
blow given by a hammer moving in an inclined direction, and which was
thrown up by a cam and thrown down by springs. The more I reflected
upon it the more I became convinced that a successful stone-dressing
machine could be made on those general lines, and in no other way; and
I also became impressed with what seems the almost absurd conviction
that I could make it.
The machine that broke the stone had a broad hammer--a cast-iron plate
with tongues on the sides running in grooves in a frame, and to the
end of which a long steel blade was bolted. My first idea was to divide
the single broad hammer into several hammers working side by side and
striking their blows successively; the second was to separate the
hammers from the tool-holders, the third, to employ the same tools that
were used by stone-cutters, namely, the point, tooth-chisel and drove,
and to give them as nearly as possible the same blow that was given to
them by the workman, and the fourth, to give to the tools only the blow
necessary to do their work.
I infused my own enthusiasm into my associates to such a degree that
they agreed to put up the money and let me try the experiment. That
also is something that I now wonder at.
The most influential member of this devoted band was George T. Hope,
President of the Continental Fire Insurance Co., a gentleman whom I
shall have frequent occasion to mention, and who remained my steadfast
friend till his death, which occurred soon after the close of my
engineering career.
I set about my work in this manner. My house, on the south side of
Twenty-second Street west of Seventh Avenue, had been arranged in
its construction to use the extension room back of the parlor as a
dining-room. That left the front basement available for me. This
I equipped for a drawing-office, and set myself at work to learn
mechanical drawing, and at the same time to design this machine.
I bought a Scotch instruction book, and a sheet of “antiquarian”
drawing-paper. In those days all drawings were made on white linen
paper, and this was nearly the largest size that was made, and cost 75
cents a sheet. My principal drawing-implement was india-rubber. As my
plans grew in my mind I had to rub out my preceding sketches. I spent
a great deal of my time in visiting the large engineering works on
the East River--the Allaire Works, the Morgan Works and the Novelty
Works--and studying tools and machines and principles and methods
of construction. I tried to get my mind saturated with mechanics. I
finally succeeded in producing the design, this vertical section of
which I have sketched from memory after fifty years.
It will be seen that this machine was massive in its construction.
This was required on account of the speed--300 rotations of the shaft
per minute--at which I had determined to run it. This was my first
employment of high speed.
[Illustration: GEORGE T. HOPE]
The original model of the machine made 60 strokes per minute. In the
machine that broke the stone I had increased the speed to 100 strokes
per minute. In designing the successful machine I made the great jump
to 300 revolutions of the cam-shaft per minute. This was done after
much study of practical requirements. I observed carefully the speed
of planing-machines. I had also the opportunity of witnessing the
operation of the first wood-moulding machine, and was much impressed by
the speed of the rotary cutters and the rapidity with which the work
was turned out. I wanted a motion of 40 inches a minute for the stone
table, which would make the output of the machine satisfactory; 300
revolutions would give this motion, the table advancing .133 of an inch
at each blow.
[Illustration: Side frame not shown, except Channels
for Elevating Screws
My First Mechanical Drawing. Longitudinal Section of my
Stone-dressing Machine.]
The machine contained six hammers, each 6 inches wide and weighing
about 200 pounds, which ran in a suspended frame. The front member of
this frame was a wrought-iron bar 6 inches square, with a projection
on the lower side, as shown. At the ends this bar was first reduced to
5 inches square, the corners rounded to 1 inch radius, and mortised
into cast-iron side-bars 4 inches thick, one of which is shown in the
sectional view. Beyond these side-bars the wrought-iron bar was turned
down to journals 3¹⁄₂ inches in diameter, which turned in the heads of
large screws, one of which is represented. Beyond those journals it
was further reduced to 2 inches diameter, and the ends threaded. These
projections extended through slots in the main framing, and nuts on the
outside provided with long handles enabled the whole to be bound fast
in its position, when that had been determined.
The hammers had two faces; the upper faces struck on this 6-inch square
bar, the lower faces struck the backs of the heavy tool-holders. These
tool-holders were held in position in the manner shown. At the extreme
back end they rocked downward upon a heavy cross-bar. At the front they
rose against the 6-inch cross-bar. They were made with a heavy hook
at the back, which prevented them from coming forward further than
the projection at the bottom of this cross-bar permitted. A curved
spring held them up to the cross-bar when the weight of the hammer
was removed. Between the 6-inch cross-bar and the tool-holders and
the hammer faces I introduced a sheet of heavy leather belting, which
deadened the force of the blow. A stone-cutter uses a wooden mallet to
drive the tooth-chisels and droves, because the impact of iron on iron
has a disintegrating effect upon the stone, which the stone-cutters
call “stunning the stone.” It produces a vibration in the body of the
stone to a depth of perhaps ¹⁄₈ inch, and, however well the surface of
the stone may appear when it is finished, after a while the outside
will flake off to the depth to which these vibrations have extended.
This leather buffer served the purpose of the wooden mallet, completely
avoiding this difficulty. Incidentally also it made the building
habitable, by transforming the blow into a dull thud, which at the
rate of 1800 blows per minute from the six hammers was itself quite
important to be done.
The large screws on each side of the machine at the front were provided
at the top with long nuts resting on a cross-bar and combined with
worm-wheels. A shaft carrying two worms engaging with these wheels
extended across the top of the machine, so that the nuts were rotated
identically, and the front of the suspended frame was raised or lowered
as the thickness of the stone or depth of the cut required. The machine
could cut stone from the thinnest ashlar up to a thickness of about 3
feet. The hammers ran on rollers as shown. At the back the frame and
hammers were carried on similar rollers on the same shaft. The ends of
this shaft also turned in square heads of screws, and by a mechanism
similar to that already described the back of the frame could be
elevated or depressed to the height required and be set at any desired
angle.
The six tool-holders were made in the following manner: I got from
England a bar of steel long enough to make them all. This was planed
into the form shown in the section, and the sockets for the shanks of
the tools were finished to an equal depth and perfectly in line. It was
then parted, and the ends of each finished in a slotting-machine.
The blows struck by the hammers were very effective. The cams had a
throw of 1¹⁄₄ inches, but they threw the hammers back against the
springs 1¹⁄₄ inches further, making their fall 2¹⁄₂ inches. This I
ascertained by holding a piece of thin board edgeways between the upper
end of a hammer and the cross-bar at the back, when the hammer crushed
it up to this height.
We never ran over the stone with the points but once. They made
everything before them fly. On the other hand, the droves merely dusted
the surface, to take out the marks of the tooth-chisels. All surplus
force in the blow was received on the 6-inch cross-bar. The tools
stood motionless unless pushed back by the stone, when they received a
sufficient portion of the blow to drive them forward to their position.
The feed motion was powerful, being imparted by a worm engaging in a
worm-wheel 24 inches in diameter, while the run back was swift, quite
100 feet in a minute.
The sides of the steel tool-holders, rubbing against each other,
became after a while badly abraded. I was obliged to plane them off
and dovetail thin strips of hardened steel into them. These prevented
any further trouble. The sides of the end tool-holders, however, which
rubbed against the cast-iron side-bars, I observed, were polished
without sensible wear.
This was a very important observation. These surfaces all rubbed
together dry. The pressure was only the side thrust, which was very
trifling. Under these conditions the molecules of the same material
interlocked, while those of the different materials did not. These
two materials were, however, extremely different in their constituent
features. Perhaps this point of freedom of _some_ different materials
from interlocking was still better illustrated by the set-screws,
where this difference of molecular structure did not exist in the same
degree. These were made of Ulster iron, a superior quality of American
iron then largely used in New York City for bolts. They were ⁵⁄₈-inch
screws, and were also used dry, no oil being allowed anywhere over
the stones. Each tool-holder contained three of these set-screws.
The outside ones were tightened and loosened sixty times every day.
The middle ones, where only the points were used, were tightened and
loosened twenty times every day and at other times stood loose in their
threads. The tool-holders being massive, and the blows of the hammers
also coming on the leather cushion, there was no vibration. At the end
of the two years’ running the outer bolts were all perfect fits. The
middle ones were loose, but still held the tools perfectly.
The rollers on which the hammers ran were hardened and turned on
hardened shafts. The hammers themselves had chilled faces, and their
surfaces running on the rollers were also chilled. The surfaces of
the tool-holders and of the bar on which these rocked were provided
with hardened strips to the extent that they came in contact with each
other. The cams and rollers and their pins were also hardened.
When built this machine was found to require only a single alteration.
I had welded the cams onto the shaft, the welds being guaranteed by
the smith to be perfectly sound. No appearance of unsoundness could be
detected when the shaft was finished, but after running a week or two
the cams became loose. This also gave me a useful lesson. I was obliged
to send to England for blocks of steel, which were bored, finished and
keyed on the shaft in the manner shown, and the working surfaces of
the cams were hardened. This required the substitution of new hammers,
because the cams could not be threaded through the old ones. The hubs
of these cams were 6 inches long, covering the shaft.
Our company, being satisfied from its design that the machine when
finished would prove a success, rented from Mr. Astor a large lot on
the south side of Fourteenth Street, west of Ninth Avenue, extending
through to Thirteenth Street, and erected and equipped a building and
established a stone-yard, where the machine ran successfully for two
seasons, principally employed in facing ashlar, as the flat-faced
stones of buildings are termed. It turned out with ease 600 square feet
of finished surface per day, which was the work of thirty men, and it
never broke a stone, however thin.
For facing in the machine the stones were set on bars 2 inches thick
and 4 inches high, cast on the surface of sliding tables. These were
both longitudinal and cross bars, and were provided with holes ³⁄₄ inch
in diameter and about 3 inches apart. There were two tables, each 16
feet in length.
Several pieces of ashlar were set upon each table and held by dogs
and wedges on these bars. They were wedged up very easily by skilled
workmen, so that they would finish at the same level. At one side
of the ways on which the tables moved, near each end, was placed a
swing-crane, which was double- and triple-geared, so that by means of
it any stone that the machine was adapted to cut could be lifted by two
men. The operations of cutting the stones on one table and removing the
stones and setting others on the other table went on simultaneously,
so that the cutting was never interrupted, except to change the tools
and the tables. This last was done as follows: Each table, when the
work on it was completed, was run rapidly backward or forward to attach
it to the other table. It was then connected with this by a couple of
hooks, and, the motion being reversed, pulled it into place under the
tools, and in doing this took its own place under a crane, so that the
work of removing the finished stones and setting rough ones went on
continuously at one end or the other of the ways.
In addition to the machine I designed the building and the whole plant
and the plan of its operation, which moved like clockwork. I made every
drawing myself. The cranes I obtained in Rochester, N. Y., of a pattern
which the builders made for railroads for handling heavy freight.
I bought from a stone-dressing company that had failed a rubbing
machine called the Jenny Lind rubber, from the fact that it was started
the same year in which that songstress was brought to the United States
by Mr. Barnum. This rubbing-machine was quite a success. From a central
vertical spindle a jointed arm extended in three lengths, each about 12
feet long. The sections of this arm were very deep, so that there was
no sag at the end, where the rubbing-plate was driven by belting and
could be moved from stone to stone around a circle of 36 feet radius.
Half of this circle was sufficient for our use. I made only one change
in this machine. The pulleys, two pairs on each joint, one at the top
and one at the bottom, about two feet in diameter by three inches
face, were of course horizontal. The makers were afraid the belts
would fall off; so they made these pulleys with two square grooves,
¹⁄₂ inch wide by ¹⁄₄ inch deep, in their faces, and had corresponding
strips of leather sewn on the belts to run in these grooves. I threw
all these away and substituted ordinary pulleys with their faces
slightly crowning. Never had the least trouble. Indeed, these pulleys
did better than I expected. I supposed the belts would need to be taken
up occasionally, on account of becoming stretched, but they did not.
Perhaps they would have done so if the strain on them had been greater.
This rubbing machine resembled the stone-dressing machine in one
respect: everything about it was arranged for continuous operation and
the largest output.
The business was carried on the first season under the management of
Mr. John McClave, a master stone-cutter, and the second season under
the management of the firm of Brown & Young, stone-cutters. Mr. Hugh
Young, of this firm, has since been prominent in the stone-cutting
business in New York.
The machine was found to possess a remarkable advantage over hand work.
The sun was called by stone-cutters “the great revealer.” When its rays
fell at a small angle on a surface finished by hand they showed very
considerable irregularities. The same test showed work in the machine
to be true planes. It won a high reputation; stone-cutters were anxious
to get their surfaces done in the machine, and we had more work offered
us than we could do.
The following incident illustrates the favorable impression made by the
machine upon everyone who witnessed its operation:
At a meeting of the Directors of the Company at which I was present Mr.
Daniel S. Miller, a gentleman somewhat prominent in financial New York,
was late. He made the following explanation. “I thought that before the
meeting I would visit the stone yard and see how the work was going on.
I stayed longer than I had intended, and I want five thousand dollars
more of the stock of this company.”
We were much elated over our success, and plans were made for enlarging
the business. I completed the drawings for an additional machine, wide
enough to take in platforms, for which provision had been made by me in
the plan of the building. The only change suggested by our two years’
experience was the use of air-cushions behind the hammers in place of
steel springs.
But the best-laid schemes o’ mice an’ men, the poet tells us,
“Gang aft a-gley;
And leave us naught but grief and pain
For promised joy.”
Our plans were suddenly ruined. A change in the method of facing
ashlar was introduced and soon became universally adopted. Instead
of being faced by hand, it began to be sawn out of large blocks. I
have since wondered why this had not been done long before. Blocks of
marble had been sawn into slabs by gang-saws no one knows how long,
and all that had to be done was to apply the same system to blocks of
building-stone. It was found to cost no more to saw ashlar than it
had done to split it out at the quarry. All the cost of facing and
much stone were saved. Our stone-cutting machine became useless, and I
learned that disappointments were not confined to the legal profession.
The speed of 300 revolutions per minute had proved to be admirably
suited for the machine. Familiarity with this speed in the running of
the stone-dressing machine made me alive to the value of high rotative
speeds in all cases to which they are adapted.
In looking back over this period I see that the success of the
stone-dressing machine was due to the following causes:
First, I went about the work of facing stone by machinery in the
natural way.
Second, the machine was superabundantly strong and substantial in every
part.
Third, it was made with absolute mechanical truth.
Fourth, the speed was splendid.
Fifth, the blow was peculiar. In the Hastings machine the cutting-tool
was driven into the stone. In mine it rested on the stone and was
moved back horizontally by the feed. This changed slightly the angular
position of the tool-holder, so that the blow was received by it at
the lower edge of its back. This gave to the tool a motion forward and
_upward_, so that the vertical effect on the stone was trifling.
This was the vital feature of my improvement, and that in a double
sense; for it was only by convincing my associates beforehand that a
machine operating in this manner could not break the stone that I was
able to obtain their financial support.
Sixth, the two-faced hammer saved the stone from all unnecessary force
of the blow.
The final cause of its success was the two-table system. The two
operations of setting and cutting occupied each about the same time,
and twenty tables each averaging thirty square feet of surface,
measured after being squared up, were easily finished in a day of ten
hours.
A description of some of the constructive methods employed by me may be
interesting:
The bar of steel which was to be made into six separate tool-holders
had to have eighteen sockets mortised in it. These were 1 inch square.
I had made the tools with square shanks so as to insure their proper
position. These mortises must be absolutely in line and of equal depth.
These objects were accomplished as follows: A cast-iron angle-bar with
planed surfaces was first bolted on the table of the drilling-machine,
and for drilling the holes the bar of steel was kept in contact
with this angle-bar. A uniform depth was insured by employing a
bottoming-drill with a collar formed on the shank. The drilling was
finished when this collar rubbed on the steel bar.
I had this work done by Mr. Joseph Banks, whose shop was in a large
building at the corner of Second Avenue and Twenty-second Street. Mr.
A. S. Cameron, the inventor and manufacturer of the celebrated Cameron
steam-pumps, was then an apprentice in that shop. Mr. Banks was an
excellent mechanic, and I was greatly indebted to him for the accuracy
of the work that I procured. He devised an expanding-drill to cut a
groove at the bottom of these sockets, in which the chips from the
slotting-tool made in squaring the holes would come off. The finishing
slotting-tool I designed myself. I had noticed in all slotting-machines
that came under my observation at that time that the tool would spring
off a little at the commencement of the cut, so that a full square
angle was never obtained. To avoid this defect and to size the slots
equally I made a slotting-tool to cut on opposite sides. The cutting
edges were each about ¹⁄₈ inch long and the corners rounded. The bar
for the tool-holders had to be set three times on account of its
length. It was set in contact with the same angle-bar, which was bolted
on this table parallel with its transverse feed. This finishing-tool
being once set, the upper and lower faces of all the sockets were thus
readily finished in perfect line and with square edges. The tool being
then turned at right angles to its first position, for which purpose
its shank had been planed square, finished the sides of the sockets.
These were identical in every respect, and any tool could go anywhere.
The springs behind the hammers were prepared with great care. I had
large bars of spring steel reduced under a tilt-hammer to a section ³⁄₈
inch square. These were coiled with only ¹⁄₄ inch space between the
coils, so that in case a spring broke within the hammer it could not
get out of place. These springs were exceptionally durable. We took off
the back cross-bar occasionally--perhaps once a month--to examine for
broken springs, and sometimes we found one, which was replaced with
a new one because we assumed that it was fatigued, but the hammers
worked just as well with broken springs as they did with whole ones.
The springs, having considerable initial compression, did not become
loose.
It seems proper to add that, except the help from Mr. Banks, I did not
in designing the machine or organizing the work receive assistance or
suggestion from anyone.
With these details I bid a final good-by to you, my old schoolmaster. I
have a warm place in my heart for you. You set me my first lessons in
mechanics. Your life was short. You were not ordained to cut much of a
figure in the world. But you were faithful. You always did your work
and did it well.