GENERATING MECHANICAL POWER TO DRIVE MODERN FARM MACHINERY
At one time ninety-seven per cent of the population of the United States
got their living directly from tilling the soil, and the power used was
oxen and manual labor. At the present time probably not more than
thirty-five per cent of our people are actively engaged in agricultural
pursuits. And the power problem has been transferred to horses, steam,
gasoline, kerosene and water power, with electricity as a power
conveyor.
Fifty years ago a farmer was lucky if he owned a single moldboard
cast-iron plow that he could follow all day on foot and turn over one,
or at most, two acres. The new traction engines are so powerful that it
is possible to plow sixty feet in width, and other machines have been
invented to follow the tractor throughout the planting and growing
seasons to the end of the harvest. The tractor is supplemented by
numerous smaller powers. All of which combine to make it possible for
one-third of the people to grow enough to feed the whole American family
and to export a surplus to Europe.
At the same time, the standard of living is very much higher than it was
when practically everyone worked in the fields to grow and to harvest
the food necessary to live.
Farm machinery is expensive, but it is more expensive to do without.
Farmers who make the most money are the ones who use the greatest power
and the best machinery. Farmers who have a hard time of it are the ones
who use the old wheezy hand pump, the eight-foot harrow and the walking
plow. The few horses they keep are small and the work worries them. The
owner sympathizes with his team and that worries him. Worry is the
commonest form of insanity.
[Illustration: Figure 99.--Flail, the oldest threshing machine, still
used for threshing pedigreed seeds to prevent mixing. The staff is seven
or eight feet long and the swiple is about three feet long by two and
one-half inches thick in the middle, tapering to one and one-half inches
at the ends. The staff and swiple are fastened together by rawhide
thongs.]
[Illustration: Figure 100.--Bucket Yoke. It fits around the neck and
over the shoulders. Such human yokes have been used for ages to carry
two buckets of water, milk or other liquids. The buckets or pails should
nearly balance each other. They are steadied by hand to prevent
slopping.]
At a famous plowing match held at Wheatland, Illinois, two interesting
facts were brought out. Boys are not competing for furrow prizes and the
walking plow has gone out of fashion. The plowing at the Wheatland
plowing match was done by men with riding plows. Only one boy under
eighteen years was ready to measure his ability against competition. The
attendance of farmers and visitors numbered about three thousand, which
shows that general interest in the old-fashioned plowing match is as
keen as ever. A jumbo tractor on the grounds proved its ability to draw
a big crowd and eighteen plows at the same time. It did its work well
and without vulgar ostentation. Lack of sufficient land to keep it busy
was the tractor's only disappointment, but it reached out a strong
right arm and harrowed the furrows down fine, just to show that it
"wasn't mad at nobody."
[Illustration: Figure 101.--Well Sweep. The length of the sweep is
sufficient to lower the bucket into the water and to raise it to the
coping at the top of the brickwork. The rock on the short end of the
sweep is just heavy enough to balance the bucket full of water.]
Modern farm methods are continually demanding more power. Larger
implements are being used and heavier horses are required to pull them.
A great deal of farm work is done by engine power. Farm power is
profitable when it is employed to its full capacity in manufacturing
high-priced products. It may be profitable also in preventing waste by
working up cheap materials into valuable by-products. The modern,
well-managed farm is a factory and it should be managed along
progressive factory methods. In a good dairy stable hay, straw, grains
and other feeds are manufactured into high-priced cream and butter.
[Illustration: Figure 102.--Wire Stretcher. A small block and tackle
will stretch a single barb-wire tight enough for a fence. By using two
wire snatches the ends of two wires may be strained together for
splicing.]
[Illustration: Figure 103.--Block and Tackle. The rope is threaded into
two double blocks. There is a safety stop that holds the load at any
height.]
Farming pays in proportion to the amount of work intelligently applied
to this manner of increasing values. It is difficult to make a profit
growing and selling grain. Grain may sell for more than the labor and
seed, but it takes so much vitality from the land that depreciation of
capital often is greater than the margin of apparent profit. When grains
are grown and fed to live-stock on the farm, business methods demand
better buildings and more power, which means that the farmer is
employing auxiliary machinery and other modern methods to enhance
values.
In other manufacturing establishments raw material is worked over into
commercial products which bring several times the amount of money paid
for the raw material.
[Illustration: Figure 104.--Farm Hoists. Two styles of farm elevating
hoists are shown in this illustration. Two very different lifting jobs
are also shown.]
The principle is the same on the farm except that when a farmer raises
the raw material he sells it to himself at a profit. When he feeds it to
live-stock and sells the live-stock he makes another profit. When the
manure is properly handled and returned to the soil he is making another
profit on a by-product.
Farming carried on in this way is a complicated business which requires
superior knowledge of business methods and principles. In order to
conduct the business of farming profitably the labor problem has to be
met. Good farm help is expensive. Poor farm help is more expensive.
While farm machinery also is expensive, it is cheaper than hand labor
when the farmer has sufficient work to justify the outlay. It is
tiresome to have agricultural writers ding at us about the superior acre
returns of German farms. German hand-made returns may be greater per
acre, but one American farmhand, by the use of proper machinery, will
produce more food than a whole German family.
[Illustration: Figure 105.--Two Powerful Winches. The one to the left is
used for pulling small stumps or roots in the process of clearing land.
The rope runs on and off the drum to maintain three or four laps or
turns. The winch to the right is used for hoisting well drilling tools
or to hang a beef animal. The rope winds on the drum in two layers if
necessary.]
DOG CHURN
Even the dog works on some farms. A dog is a nuisance among dairy
cattle, but he can be made to earn his salt at churning time. All
mechanism in connection with dog power must be light. It also is
necessary to eliminate the friction as much as possible.
[Illustration: Figure 106.--Dog Churn Power. A wheel keyed to an iron
shaft is placed at an angle as shown. The weight of the dog turns the
wheel and power is conveyed to the churn by a light rope belt. It is
necessary to confine the dog between stationary partitions built like a
stall over the wheel.]
The best way to make a dog power is to use a light wooden sulky wheel
for the revolving turn table. Next best to the sulky wheel is a light
buggy wheel. The wheel is made fast to an upright iron shaft that is
stepped into an iron oil well at the bottom and inclined at an angle of
about fifteen degrees to give the necessary power. To steady the top of
the shaft a light boxing is used, preferably a ball-bearing bicycle race
to reduce friction. Power is conveyed to the churn by means of a grooved
pulley on the top of the shaft. A small, soft rope or heavy string belt
runs from this pulley to a similar pulley connected with the churn.
Dogs learn to like the work when fed immediately after the churning is
finished. Dogs have been known to get on to the power wheel to call
attention to their hungry condition. This calls to mind the necessity
of arranging a brake to stop the wheel to let the dog off. When the
wheel is running light, the dog cannot let go.
A spring brake to wear against the iron tire of the wheel is the most
satisfactory. The brake may be tripped and set against the tire
automatically by a small lever and weight attached to the underside of
the wheel. When the speed is too fast the weight swings out and sets the
brake. When the speed slackens the weight drops back towards the center
and releases the brake. When the speed is about right the weight swings
between the two spring catches.
BULL TREADMILL
On dairy farms it is common to see a valuable pure bred bull working a
treadmill for exercise and to pump water. Sometimes he turns the
cream-separator, but the motion is too unsteady for good results.
Treadmills for this purpose are very simple. The mechanism turns a
grooved pulley which propels a rope power conveyor. The rope belt may be
carried across the yards in any direction and to almost any distance.
Bull treadmills consist of a framework of wood which carries an endless
apron supported on rollers. The apron link chains pass around and turn
two drumhead sprocket-wheels at the upper end and an idler drum at the
lower end. The sprocket-wheel drum shaft is geared to an auxiliary shaft
which carries a grooved pulley. A rope belt power conveyor runs in this
groove and carries power from the bull pen to the pump.
Bull tread powers usually have smooth inclined lags, because a bull's
steps on the tread power are naturally uneven and irregular. This
construction gives an even straight tread to the travel surface. To
prevent slipping, soft wooden strips are nailed onto the lags at the
lower edges. Even incline tread blocks or lags are also recommended for
horses that are not shod and for all animals with split hoofs. The
traveling apron of the power is placed on an incline and the treads are
carried around the two drums at the upper and lower ends of the frame by
means of endless chains. There is a governor attachment which regulates
the speed and prevents the machinery from "running away."
[Illustration: Figure 107.--Bull Tread Power. Treadmills have gone out
of fashion. Too much friction was the cause, but a mill like this is
valuable to exercise a pure bred bull. Some dairymen make him pump
water.]
The simplest governor is made on the two-ball governor principle with
weights on opposite levers. The governor is attached to two opposite
spokes in the flywheel. As the speed increases the weights move outward
because of their centrifugal force. This motion operates a brake lever
to retard or stop the flywheel. When the machine stops an opposite
weight rests against the flywheel until it starts in motion again, so
the apron cannot be moved until the brake is released. This is necessary
to get the animal on or off of the platform while it is at rest to avoid
accidents. The usual incline is a rise of two feet in eight when power
is wanted. This pitch compels the bull to lift one-quarter of his own
weight and it may be too severe for a heavy animal. The endless apron is
an endless hill climb to the bull. Treadmills are not economical of
power because there are so many bearings to generate friction.
WINDMILLS
Wind power is the cheapest power we have. A windmill properly
proportioned to its work is a great help, especially when it is attached
to a good pump for the purpose of lifting water into an elevated tank
from which it is piped under pressure for domestic purposes and for
watering live-stock.
You can have considerable patience with a windmill if you only depend
upon it for pumping water, provided you have a tank that will hold a
week's supply to be drawn during a dry, hot time when every animal on
the farm demands a double allowance of water. That is the time when a
farmer hates to attach himself to the pump handle for the purpose of
working up a hickory breeze. That also is the time when the wind
neglects a fellow.
A good windmill is useful up to about one-third of its rated capacity,
which is the strongest argument for buying a mill larger than at first
seems necessary. Some men have suffered at some time in their lives with
the delusion that they could tinker with a poorly constructed windmill
and make it earn its oil. They have never waked up to a full
realization of their early delusion. It is a positive fact that all
windmills are not lazy, deceitful nor wholly unreliable. When properly
constructed, rightly mounted and kept in good repair, they are not prone
to work in a crazy fashion when the tank is full and loaf when it is
empty. There are thousands of windmills that have faithfully staid on
the job continuously twenty-four hours per day for five or ten years at
a stretch, all the time working for nothing year after year without
grumbling, except when compelled to run without oil. At such times the
protest is loud and nerve racking.
A good windmill with suitable derrick, pump and piping may cost $150.
The yearly expense figures something like this:
Interest on investment at 6% per annum $ 9.00
Depreciation 10% 15.00
Oil 1.00
Repairs 3.00
making a total of $28, which is less than $2.50 per month for the work
of elevating a constant supply of water for the house, stable and
barnyard.
ONE-MULE PUMP
A home-made device that is much used on live-stock ranches in California
is shown in the illustration. This simple mechanism is a practical means
for converting circular mule motion into vertical reciprocating pump
action. A solid post is set rather deep in the ground about twelve feet
from the well. This post is the fulcrum support of the walking-beam. One
end of the walking-beam reaches to the center line of the well, where it
connects with the pump shaft. The other end of the walking-beam is
operated by a pitman shaft connecting with a crank wrist pin near the
ground. A round iron shaft similar to a horsepower tumbling rod about
ten or twelve feet in length and one and a half inches in diameter is
used to convey power and motion to the pitman shaft.
[Illustration: Figure 108.--Mule Pump. A practical home-made power to
pump water for live-stock. It is used where the water-table is within 20
feet of the surface of the ground. The drawing shows a post in the
center which supports the walking-beam and acts as a fulcrum. A
mowing-machine wheel is keyed to one end of a round iron shaft. The
other end of this shaft turns in a boxing which is swiveled to a short
post as shown at _B_. See also detail "_B_.". The two plunger shafts are
shown at _A_ _A_. The mule is hitched to the round iron shaft near the
traveling wheel by means of a round hook. As the mule walks around in a
circle the shaft revolves and operates the crank _B_. There are side
guys not shown in the drawing to keep the walking-beam in position.]
A mowing-machine wheel is keyed to the outer end of the tumbling rod. At
the crank end is a babbitted boxing with a bolt attachment reaching down
into the top of a short post set solidly into the ground, directly under
the inner end of the walking-beam. This bolt permits the boxing to
revolve with a swivel motion. Another swivel connects the upper end of
the pitman shaft with the walking-beam. The whiffletree is attached to
the tumbling rod by an iron hook. This hook is held in place by two iron
collars fastened to the tumbling rod by means of keys or set-screws.
The mowing-machine drive wheel travels around in a circle behind the
mule turning the shaft which works the walking-beam and operates the
pump. It would be difficult to design another horse or mule power so
cheap and simple and effective. The mule grows wise after a while, so it
is necessary to use a blindfold, or he will soldier on the job. With a
little encouragement from a whip occasionally a mule will walk around
and around for hours pulling the mowing-machine wheel after him.
HORSEPOWER
One horsepower is a force sufficient to lift 33,000 pounds one foot high
in one minute.
The term "horsepower" in popular use years ago meant a collection of
gear-wheels and long levers with eight or ten horses solemnly marching
around in a circle with a man perched on a platform in the center in the
capacity of umpire.
This was the old threshing-machine horsepower. It was the first real
success in pooling many different farm power units to concentrate the
combined effort upon one important operation.
Not many horses are capable of raising 33,000 pounds one foot in one
minute every minute for an hour or a day. Some horses are natural-born
slackers with sufficient acumen to beat the umpire at his own game. Some
horses walk faster than others, also horses vary in size and capacity
for work. But during a busy time each horse was counted as one
horsepower, and they were only eight or ten in number. And it so
developed that the threshing horsepower had limitations which the
separator outgrew.
The old threshing horsepower has been superseded by steam engines and
gasoline and kerosene power, but horses are more important than ever.
[Illustration: Figure 109.--Horse Power, showing the manner of attaching
the braced lever to the bull wheel.]
Farm horses are larger and more powerful; they are better kept, better
trained, and hitched to better machinery, because it pays. One man
drives three 1,600-pound draft horses as fast as he used to drive two
1,000-pound general-purpose horses. The three drafters make play of a
heavy load, while the two light horses worry themselves poor and
accomplish little. Modern farm machinery is heavier, it cuts wider and
digs deeper and does more thorough work. Modern farm requirements go
scientifically into the proper cultivation and preparation of soil to
increase fertility. Old methods used up fertility until the land refused
to produce profitably.
Although the old familiar horsepower has been greatly outclassed, it has
not been discarded. There are many small horsepowers in use for
elevating grain, baling hay, cutting straw for feed and bedding,
grinding feed and other light work where engine power is not available.
WATER-POWER
Water-power is the most satisfactory of all kinds of stationary farm
power, when a steady stream of water may be harnessed to a good
water-wheel. It is not a difficult engineering feat to throw a dam
across a small stream and take the water out into a penstock to supply
water to a turbine water-wheel. In the first place it is necessary to
measure the flow of water to determine the size of water-wheel which may
be used to advantage. In connection with the flow of water it is also
important to know the fall. Water is measured by what is termed a
"weir." It is easily made by cutting an oblong notch in a plank placed
across the stream, as a temporary dam which raises the water a few
inches to get a steady, even flow of water through the notch so that
calculations may be made in miner's inches. The term "miner's inch" is
not accurate, but it comes near enough for practical purposes. Measuring
the volume of water should be done during a dry time in summer.
The fall of the stream is easily measured by means of a carpenter's
level and a stake. The stake is driven into the ground at a point
downstream where water may be delivered to the wheel and a tailrace
established to the best advantage. Sighting over the level to a mark on
the stake will show the amount of fall. When a manufacturer of
water-wheels has the amount of water and the fall, he can estimate the
size and character of wheel to supply. The penstock may be vertical or
placed on a slant. A galvanized pipe sufficient to carry the necessary
amount of water may be laid along the bank, but it should be thoroughly
well supported because a pipe full of water is heavy, and settling is
likely to break a joint.
Galvanized piping for a farm penstock is not necessarily expensive. It
may be made at any tin shop and put together on the ground in sections.
The only difficult part about it is soldering the under side of the
joints, but generally it may be rolled a little to one side until the
bottom of the seam is reached.
The most satisfactory way to carry power from the water-wheel to the
farm buildings is by means of electricity. The dynamo may be coupled to
the water-wheel and wires carried any required distance.
The work of installing electric power machinery is more a question of
detail than mechanics or electrical engineering. The different
appliances are bought from the manufacturer and placed where they are
needed. It is principally a question of expense and quantity of
electricity needed or developed. If the current is used for power, then
a motor is connected with the dynamo and current from the dynamo drives
the motor. A dynamo may be connected with the water-wheel shaft at the
source of power and the motor may be placed in the power-house or any of
the other buildings.
The cost of farm waterworks depends principally on the amount of power
developed. Small machinery may be had for a few hundred dollars, but
large, powerful machinery is expensive. If the stream is large and
considerable power is going to waste it might pay to put in a larger
plant and sell current to the neighbors for electric lighting and for
power purposes. Standard machinery is manufactured for just such plants.
The question of harnessing a stream on your own land when you control
both banks is a simple business proposition. If anyone else can set up a
plausible plea of riparian rights, flood damage, interstate
complications or interference with navigation, it then becomes a
question of litigation to be decided by some succeeding generation.
STEAM BOILER AND ENGINE
Farm engines usually are of two different types, steam engines and
gasoline or oil engines. Steam stationary engines are used on dairy
farms because steam is the best known means of keeping a dairy clean and
sanitary. The boiler that furnishes power to run the engine also
supplies steam to heat water and steam for sterilizing bottles, cans and
other utensils.
For some unaccountable reason steam engines are more reliable than
gasoline engines. At the same time they require more attention, that is,
the boilers do. Steam engines have been known to perform their tasks
year after year without balking and without repairs or attention of any
kind except to feed steam and oil into the necessary parts, and
occasionally repack the stuffing boxes.
On the other hand, boilers require superintendence to feed them with
both fuel and water. The amount of time varies greatly. If the boiler is
very much larger than the engine, that is, if the boiler is big enough
to furnish steam for two such engines, it will furnish steam for one
engine and only half try. This means that the fireman can raise 40 or 60
pounds of steam and attend to his other work around the dairy or barn.
Where steam boilers are required for heating water and furnishing steam
to scald cans and wash bottles, the boiler should be several horsepower
larger than the engine requirements. There is no objection to this
except that a large boiler costs more than a smaller one, and that more
steam is generated than is actually required to run the engine. The kind
of work required of a boiler and engine must determine the size and
general character of the installation.
Portable boilers and engines are not quite so satisfactory as
stationary, but there are a great many portable outfits that give good
satisfaction, and there is the advantage of moving them to the different
parts of the farm when power is required for certain purposes.
SMALL GASOLINE ENGINES
A gasoline engine of 2-1/2 horsepower is the most useful size for a
general purpose farm engine. It is convenient to run the pump,
washing-machine, fanning-mill, cream-separator, grindstone, and other
similar farm chores that have heretofore always been done by human
muscle. A small engine may be placed on a low-down truck and moved from
one building to another by hand. One drive belt 20 or 30 feet long,
making a double belt reach of 12 or 15 feet, will answer for each
setting.
The engine once lined up to hitch onto the pulley of any stationary
machine is all that is necessary. When the truck is once placed in
proper position the wheels may be blocked by a casting of concrete
molded into a depression in the ground in front and behind each wheel.
These blocks are permanent so that the truck may be pulled to the same
spot each time.
[Illustration: Figure 110.--Kerosene Farm Engine. This is a very compact
type of engine with heavy flywheels. A longer base might sit steadier on
a wagon, but for stationary use on a solid concrete pier it gives good
service.]
A gasoline engine for farm use is expected to run by the hour without
attention. For this reason it should have a good, reliable hit and miss
governor to regulate the speed, as this type is the most economical in
fuel. It should have a magneto in addition to a six-cell dry battery. It
should be equipped with an impulse starter, a device that eliminates all
starting troubles. The engine should be perfectly balanced so as to
insure smooth running, which adds materially to the life of the engine.
With a good, solid pump jack, a 2-1/2 horsepower engine will pump water
until the tank is full, whether it requires one hour or half a day.
It is easily moved to the dairy house to run the separator. As the
cream-separator chore comes along regularly every night and every
morning, the engine and truck would naturally remain inside of the dairy
house more than any other place. If the dairy house is too small to let
the engine in, then an addition is necessary, for the engine must be
kept under cover. The engine house should have some artistic pretensions
and a coat of paint.
KEROSENE PORTABLE ENGINES
The kerosene engine is necessarily of the throttle governor type in
order to maintain approximately uniform high temperature at all times,
so essential to the proper combustion of kerosene fuel. Therefore, a
kerosene engine of the hit-and-miss type should be avoided. However,
there are certain classes of work where a throttle governor engine is at
a decided disadvantage, such as sawing wood, because a throttle governor
engine will not go from light load to full load as quickly as will a
hit-and-miss type, and consequently chokes down much easier, causing
considerable loss of time.
A general purpose portable kerosene engine is admirably suited to all
work requiring considerable horsepower and long hours of service with a
fairly steady load, such as tractor work, threshing, custom feed
grinding, irrigating and silo filling. There will be a considerable
saving in fuel bill over a gasoline engine if the engine will really run
with kerosene, or other low-priced fuel, without being mixed with
gasoline.
In choosing a kerosene engine, particular attention should be paid to
whether or not the engine can be run on all loads without smoking.
Unless this can be done, liquid fuel is entering the cylinder which will
cause excessive wear on the piston and rings. A good kerosene engine
should show as clean an exhaust as when operating on gasoline and
should develop approximately as much horsepower. Another feature is
harmonizing the fuel oil and the lubricating oil so that one will not
counteract the effects of the other.
PORTABLE FARM ENGINE AND TRUCK
[Illustration: Figure 111.--Portable Farm Engine. This engine is
permanently mounted on a low wheel truck wagon. The saw frame is
detachable and the same truck is used for spraying and other work.]
A convenient arrangement for truck and portable power for spraying,
sawing wood and irrigation pumping, is shown in the accompanying
illustration. The truck is low down, which keeps the machinery within
reach. The wheels are well braced, which tends to hold the outfit steady
when the engine is running. The saw table is detachable. When removed,
the spraying tank bolts on to the same truck frame; also the elevated
table with the railing around it, where the men stand to spray large
apple trees, is bolted onto the wagon bed.
Spraying never was properly done until the powerful engine and high
pressure tanks were invented. Spraying to be effective, should be fine
as mist, which requires a pressure of 150 pounds. There may be a number
of attachments to a spraying outfit of this kind. A pipe suspended under
the frame with a nozzle for each row is used to spray potatoes,
strawberry vines and other low down crops that are grown in rows. When
not in use as a portable engine it is blocked firmly into place to run
the regular stationary farm machinery.
HYDRAULIC RAM
The hydraulic ram is a machine that gets its power from the momentum of
running water. A ram consists of a pipe of large diameter, an air
chamber and another pipe of small diameter, all connected by means of
valves to encourage the flow of water in two different directions. A
supply of running water with a fall of at least two feet is run through
a pipe several inches in diameter reaching from above the dam to the
hydraulic ram, where part of the flow enters the air chamber of the ram.
Near the foot of the large pipe, or at what might be called the
tailrace, is a peculiarly constructed valve that closes when running
water starts to pass through it. When the large valve closes the water
stops suddenly, which causes a back-pressure sufficient to lift a
check-valve to admit a certain amount of water from the large supply
pipe into the air-chamber of the ram.
After the flow of water is checked, the foot-valve drops of its own
weight, which again starts the flow of water through the large pipe, and
the process is repeated a thousand or a million times, each time forcing
a little water through the check-valve into the air chamber of the ram.
The water is continually being forced out into the small delivery pipe
in a constant stream because of the steady pressure of the imprisoned
air in the air-chamber which acts as a cushion. This imprisoned air
compresses after each kick and expands between kicks in a manner
intended to force a more or less steady flow of water through the small
pipe. The air pressure is maintained by means of a small valve that
permits a little air to suck in with the supply of water.
[Illustration: Figure 112.--Hydraulic Ram. The upper drawing shows how
to install the ram. The lower drawing is a detail section through the
center of the ram. Water flows downhill through the supply pipe. The
intermittent action of the valve forces a portion of the water through
another valve into the air-chamber. Air pressure forces this water out
through delivery pipe. Another valve spills the waste water over into
the tailrace. An automatic air-valve intermittently admits air into the
air-chamber.]
Water may be conveyed uphill to the house by this means, sometimes to
considerable distance. The size of the ram and its power to lift water
depends upon the amount of water at the spring and the number of feet of
fall. In laying the small pipe, it should be placed well down under
ground to keep it cool in summer and to bury it beyond the reach of
winter frost. At the upper end where the water is delivered a storage
tank with an overflow is necessary, so the water can run away when not
being drawn for use. A constant supply through a ram demands a constant
delivery. It is necessary to guard the water intake at the dam. A fence
protection around the supply pool to keep live-stock or wild animals out
is the first measure of precaution. A fine screen surrounding the upper
end of the pipe that supplies water to the ram is necessary to keep
small trash from interfering with the valves.
THE FARM TRACTOR
Farm tractors are becoming practical. Most theories have had a try out,
the junk pile has received many failures and the fittest are about to
survive. Now, if the manufacturers will standardize the rating and the
important parts and improve their selling organizations the whole nation
will profit. The successful tractors usually have vertical engines with
four cylinders. They are likely to have straight spur transmission
gears, and a straight spur or chain drive, all carefully protected from
dust. And they will have considerable surface bearing to avoid packing
the soil. Some tractors carry their weight mostly upon the drive
wheels--a principle that utilizes weight to increase traction. Other
tractors exert a great deal of energy in forcing a small, narrow front
steering-wheel through the soft ground. Any farmer who has pushed a
loaded wheelbarrow knows what that means. Some kerosene tractors require
a large percentage of gasoline. The driver may be as much to blame as
the engine. But it should be corrected.
[Illustration: Figure 113.--Tractor Transmission Gear. Spur gears are
the most satisfactory for heavy work.]
Manufacturers should do more educational work and talk less about the
wonderfully marvelous and marvelously wonderful. Salesmen should study
mechanics instead of oratory. Tractor efficiency should be rated
practically instead of theoretically. The few actual reports of
performance have emanated from tests with new machines in the hands of
trained demonstrators. Manufacturers include belt power work among the
virtues of farm tractors, and they enumerate many light jobs, such as
running a cream-separator, sawing wood, pumping water and turning the
fanning-mill. Well, a farm tractor can do such work--yes. So can an
elephant push a baby carriage. If manufacturers would devise a practical
means of using electricity as an intermediary, and explain to farmers
how a day's energy may be stored in practical working batteries to be
paid out in a week, then we could understand why we should run a 20
horsepower engine to operate a cream-separator one hour at night and
another hour in the morning.
[Illustration: Figure 114.--Straight Transmission Gear, forward and
chain drive reverse, for traction engine.]