Full text of "Agricultural engineering; a text book for students of secondary schools of agriculture, colleges offering a general course in the subject and the general reader,"

See other formats

This is a digital copy of a book that was preserved for generations on library shelves before it was carefully scanned by Google as part of a project
to make the world's books discoverable online.

It has survived long enough for the copyright to expire and the book to enter the public domain. A public domain book is one that was never subject
to copyright or whose legal copyright term has expired. Whether a book is in the public domain may vary country to country. Public domain books
are our gateways to the past, representing a wealth of history, culture and knowledge that's often difficult to discover.

Marks, notations and other marginalia present in the original volume will appear in this file - a reminder of this book's long journey from the
publisher to a library and finally to you.

Usage guidelines

Google is proud to partner with libraries to digitize public domain materials and make them widely accessible. Public domain books belong to the
public and we are merely their custodians. Nevertheless, this work is expensive, so in order to keep providing this resource, we have taken steps to
prevent abuse by commercial parties, including placing technical restrictions on automated querying.

We also ask that you:

+ Make non-commercial use of the files We designed Google Book Search for use by individuals, and we request that you use these files for
personal, non-commercial purposes.

+ Refrain from automated querying Do not send automated queries of any sort to Google's system: If you are conducting research on machine
translation, optical character recognition or other areas where access to a large amount of text is helpful, please contact us. We encourage the
use of public domain materials for these purposes and may be able to help.

+ Maintain attribution The Google "watermark" you see on each file is essential for informing people about this project and helping them find
additional materials through Google Book Search. Please do not remove it.

+ Keep it legal Whatever your use, remember that you are responsible for ensuring that what you are doing is legal. Do not assume that just
because we believe a book is in the public domain for users in the United States, that the work is also in the public domain for users in other
countries. Whether a book is still in copyright varies from country to country, and we can't offer guidance on whether any specific use of
any specific book is allowed. Please do not assume that a book's appearance in Google Book Search means it can be used in any manner
anywhere in the world. Copyright infringement liability can be quite severe.

About Google Book Search

Google's mission is to organize the world's information and to make it universally accessible and useful. Google Book Search helps readers
discover the world's books while helping authors and publishers reach new audiences. You can search through the full text of this book on the web

at http : //books . google . com/|

Digitized by

Google

<^^-i-t.^^^'

ICflltlitt

Google

<2S

J/<r^ {'(^

^k^

^^ :^^-'/fz. o

GIFT or

^ tized by

Google

Digitized by

Google

Agricultural Engineering

Digitized byVjOOQlC

Farm Science Series

Agricultural Engineering

By J. B. Davidson, Iowa State College of
Agriculture and Mechanics Arts

Field Crops

By A. D. Wilson, University of Minnesota
and C. W. Wabbubton, U. S. Department of
Agriculture

Beginnings in Animal Husbandry

By C. S. Plumb, Ohio State University

SoUs and Sod Fertility

By A. R. Whitson, University of Wisconsin
and H. L. Walstkb. University of Wisconsin

Popular Fruit Growing

By S. B. Gbkkn, University of Minnesota

Vegetable Garderdng

By S. B. Gbbbn, University of Minnesota
(OTHER BOOKS IN PREPARATION)

Digitized by

Google

Digitized by

Google

a
>»

•t3

to
.3

Digitized by

Google

Agricultural Eiigifieering

A TEXT BOOK

FOR

STUDENTS OF

SECONDARY SCHOOLS OF AGRICULTURE

COLLEGES OFFERING A GENERAL

COURSE IN THE SUBJECT

AND THE

GENERAL READER

BY
J. BROWNLEE DAVIDSON, B. S., M. E.

Member American Society of Agricultural Engineers

Member American Society of Mechanical Engineers

Member Iowa Engineering Society

Pnrfessor of Agricultural Engineering, University of California

Joint Author "Farm Machinery and Farm Motors"

REVISED

Digitized by

Google

:Ti :?. .■•-

WEBB PUBLISHING COMPANY

St. Paul, Minn.

All Rights Resbbtbd

W-6

Digitized byVjOOQlC

PREFACE

Believing that the study of Agricultural Engineering
should fill an important place in the training of the young
man who would make farming the object of his life's work,
the author has attempted to furnish in this voliune an aid in
supplying this part of his training. The application of
agricultural engineering methods to agriculture should not
only raise the eflSciency of the farm worker but should also
provide for him a more comfortable and healthful home.

This volume has been written primarily as a text for
secondary schools of agriculture, and for colleges where only
a general course can be offered. Claim is not made for
much new matenai concerning the subjects discussed; but
rather an attempt has been made to place under one cover
a general discussion of agricultural engineering subjects
which hitherto could not be secured except in several vol-
mnes and hence impractical for text-book purposes.

No attempt has been made to outline the exact method
for the teaching of the subjects, as this must vary with con-
ditions. It is desirable that classwork upon the text should
be supplemented by laboratory work. The nature of the
laboratory work will depend upon the equipment available.
It is suggested that the equipments on the nearby farms
may be used to good advantage. Sample machines to be
used for study may be secured by co-operation with dealers
in farm machinery.

The author will be very glad to receive criticisms and
suggestions from those using this text, in regard to how it
may be improved and made more useful. The correction
of any errors will likewise be appreciated.

Digitized by LjOOQIC

8 PREFACE

Although written primarily for use as a text book, it is
hoped that this volume will be of interest to those engaged
in practical agriculture.

Many of the illustrations were made from photographs
secured from the files of the Iowa State College. In addi-
tion, the trade literature of the following manufacturers
was drawn upon:

International Harvester Company of America; John
Deere Plow Co. of Moline, 111.; Moline Plow Co.; W. & L.
E. Gurley; Eugene Dietzen Co.; Keuflfel and Esser Co.;
Parlinand Orendorff Co.; Fairbanks, Morse and Co.; Hayes
Pump and Planter Co. ; Hunt, Hehn, Ferris & Co. ; J. D. Tower
and Sons Co.; Western Wheeled Scraper Co.; Pattee Plow
Co.; Avery Company; Emerson-Brantingham Co.; M.
Rmnely Co.; American Seeding Machine Co.; Oliver Chilled
Plow Works; Hart-Parr Co.; Red Jacket Mfg. Co.; A. Y.
McDonald Mfg. Co.; Louden Machinery Co.; Gale Mfg. Co.;
Sandwich Mfg. Co.; Aspenwall Mfg. Co.; Wilder-Strong
Implement Co.; Port Huron Engine and Thresher Co.; J. L.
Owens Co.; Charles A. Stickney Co.; Twin City Separator
Co.; Cushman Motor Works; F. E. Meyers & Bro.; D. M.
Sechler Carriage and Implement Co.; Roderick Lean Mfg.
Co.; Janesville Machine Co.; LaCrosse Plow Co.; The John
Lanson Mfg. Co.; J. I. Case Plow Works; J. I. Case Thresh-
ing Machine Co.; Johnson & Field Mfg. Co.; Racine Sattley
Co.; Kewanee Water Supply Co.; and others.

Valuable assistance was secured from Mr. M. F. P.
Costelloe, Associate Professor of Agricultural Engineering,
Iowa State College, who read the manuscript for Parts I to
IV, inclusive. Mr. J. H. Weir, the Editor, did very efficient
work on the manuscript, which is appreciated.

Ames, Iowa. J. B. Davidson.

February, 1913.

Digitized by

Google

CONTENTS

Chapter

Introduction

Pagb
. 13

PART I— AGRICULTURAL SURVEYING

I. Definitions and Uses of Survbyinq ... 16
II. Measuring — ^The Use, Care, and Adjustment of

THE Instruments 18

III. Field Methods 24

IV. Map Making 28

V. Computing Areas 34

VI. The United States Public Land Survey . . 38

VII. Instruments for Leveling; Definitions . . 42

VIII. Leveling Practice 49

PART n— DRAINAGE

IX. Principles of Farm Drainage

X. The Preliminary Survey .

XI. Laying Out the Drainage System

XII. Leveling and Grading Tile Drains

XIII. Capacity of Tile Drains

XIV. Land Drainage

XV. Construction of Tile Drains

XVI. Open Ditches

XVII. Drainage Districts

56
64
67
73
78
86
96
103
108

PART m—IRRIGATION

XVIII. History, Extent, and Purpose of Irrigation . .111

XIX. Irrigation Culture * 115

XX. Supplying Water for Irrigation .... 122
XXI. Applying Water for Irrigation . . . 129
XXII. Irrigation in Humid Regions and Sewage Dis-
posal 136

Digitized by

Google

CONTENTS

Chapter

XXIII.

XXIV.

XXV.

XXVI.

XXVII.

XXVIII.

XXIX.

XXX.

XXXI.

XXXII.

XXXIII.

XXXIV.

XXXV.

XXXVI.

XXXVII.

XXXVIII.

XXXIX.

XL.

XLI.

XLII.

XLIII.

XLIV.

XLV.

XLVI.

XLVII.

PART IV— ROADS

Paqb

Importance op Roads 141

Earth Roads 147

* Sand-Clay and Gravel Roads .... 153

Stone Roads . 160

Road Machinery 167

Culverts and Bridges . . . . . . 175

PART V— FARM MACHINERY

The Relation op Farm Machinery to Agricul-
ture 180

Depinitions and Principles .... 186

Materials 195

The Plow 199

Harrows, Pulverizers, and Rollers . ' . 211

Seeders and Drills 223

Corn Planters 231

Cultivators 237

The Grain Binder or Harvester . . 244

Corn Harvesting Machines 251

Hay-Making Machinery 258

Machinery por Cutting Ensilage .... 273

Thrashing Machines 278

Fanning Mills and Grain Graders . . 282

Portable Farm Elevators 287

Manure Spreaders 292

Feed Mills and Corn Shellers . . . 298

Spraying Machinery 303

The Care and Repair of Farm Machinery . 309

PART VI— FARM MOTORS

XLVIII. Elementary Principles and Definitions . . 313

XLIX. Measurement op Power 316

L. Transmission op Power 320

LI. The Horse as a Motor 327

LII. EVENERS 334

LIII. Windmills 339

LIV. The Principles^ of the Gasoline Engine « . 344

Digitized by

Google

CONTENTS

Chapteb Pagb

LV. Enoinb Operation . 350

LVI. Gasounb and Oil Engine Operation . . . 354

LVn. SELEcmNO A Gasoline or Oil Engine . . 361

LVni. T&E Gas Tractor 370

LIX. The Steam Boiler 376

LX. The Steam Engine 385

LXI. The SrEi^M Tractor 389

PART Vn— FARM STRUCTURES

LXII. Introduction AND Location OF Farm Buildings . 395

LXIII. Mechanics of Materials 402

LXIV. Mechanics of Materials and Materials of

Construction 406

LXV. Hog Houses 414

LXVI. Poultry Houses 425

LXVII. Dairy Barns 436

LXVIII. Horse Barns 442

LXIX. Barn Framing 445

LXX. The Farmhouse 451

LXXI. Constructing the Farmhouse .... 455

LXXII. The Silo 461

LXXIII. The Implement House and Shop . . . 473

PART Vm— FARM SANITATION

LXXIV. The Farm Water Supply 480

LXXV. The Pumping Plant 486

LXXVI. Distributing and Storing Water .... 491

LXXVII. Plumbing for the Country House 497

LXXVIII. The Septic Tank for Disposal of Farm Sewage . 501

LXXIX. The Natural Lighting of Farm Buildings 506

LXXX. Lighting the Country Home 510

LXXXI. The Acetylene Lighting Plant .... 515

LXXXII. The Electric Lighting Plant 520

LXXXIII. Heating the Country Home .... 525

LXXXIV. Ventilation of Farm Buildings . . . .531

PART rx— ROPE WORK
LXXXV. Ropes, Knots, and Splices 537

Digitized by

Google

Digitized by

Google

Agricultural Engineering

INTRODUCTION

Engineering. Defined briefly, engineering is the art of
directing the forces of nature to do economically the work
of man. The pm^uit of agriculture requires many mechani-
cal operations which involve the use of engineering methods.

Consider the production of wheat. The plowing, the
pulverizing and smoothing of the soil, the cleaning and grad-
ing of the seed, the drilling of the seed, the harvesting, the
thrashing, and the hauling of the crop to market, are all
mechanical operations to which the skill of the mechanic or
engineer should be applied in order to obtain the best results.

In like manner, if the production of other crops be con-
sidered, it will be found that there are many operations to be
performed in connection therewith, which will require the
directing of the forces of nature or the application of engineer-
ing principles.

Agricultural Engineering. In the broadest sense, agri-
cultural engineering is intended to include all phases and
branches of engineering directly connected with the great
industry of agriculture. In America it is only recently that
the term agricultural engineering has come into general use.
The term rural engineering is used by some to designate the
same subject.

It is only within the last few years that the importance of
agricultural engineering as a branch of agricultural education
has been recognized. A knowledge of soils and of the plants

Digitized by

Google

14 :• ::: :':m^WVjATt7RJ^' ENGINEERING

and animals of the farm is essential to those who would make
good farming the aim of their Ufe's work, and these subjects
should be carefully studied by the agricultural student.
But the study of agricultural engineering is quite as impor-
tant in assuring that efficiency in farm management which
results in the greatest and most permanent benefits.

The truth of the foregoing statement is better understood
when one learns that the producing capacity or earning abiUty
of the farm worker is in direct proportion to the amount of
power one is able to control. There was a time when man
tilled the soil by his own individual efforts, depending upon
no other source of power than the strength of his own body.
Later, one beast per worker was pressed into service to draw
suitable implements. Still later, two animals were used, and
development has continued, until at the present time we have
reached the *'age of four-horse farming." In other words,
the four-horse team is now recognized as the most efficient
one for field work.

Man as a motor or producer of power is able to develop
about one-eighth of one horsepower. When use was made
of one good horse per worker, man's labor capacity was
increased eightfold. When four horses became the unit,
his efficiency was multiplied about 32 times. Just now there
is a desire to increase still further the amount of power for
each farm worker, by the use of powerful tractors or engines
arranged for drawing and operating farm implements.

The application of power to farm operations, which must
come mainly through the use of machinery, is only one branch
of agricultural engineering. Some element of agricultural
engineering is concerned in nearly every department of
agricultural endeavor. It serves man in one or both of
two ways : (1) By making it possible to increase the capacity
of the worker, as just explained; and (2) by making condi-

Digitized by

Google

INTRODUCTION 15

tions more desirable and satisfactory, either by relieving the
worker of hard labor, or by providing more healthful and
pleasing surromidings.

Fann Mechanics. The term Farm Mechanics is not as
comprehensive in meaning as AgricvUural Engineering, yet
it is often used to designate the same branch of education.
Mechanics is the science of forces and their actions; whereas
engineering proper is based upon a knowledge of these forces
and treats more particularly of the directing of them to
secure their most advantageous use.

In this text the subject of agricultural engineering is
presented under the following heads:

Agricultural Surveying.

Drainage.

Irrigation.

Roads.

Farm Machinery.

Farm Motors.

Farm Structures.

Farm Sanitation.
The importance and relation of these various branches
to agriculture are discussed in the separate parts of the text
devoted to each.

QUESTIONS

1. Define the term engineering.

2. Show how engineering methods are involved in crop production.

3. Define the term agricultural engineering.

4. Is there any relation between the producing capacity of a farm
worker and the amount and kind of power used?

6. Distinguish between "farm mechanics" and "agricultural
engineering."

6. Name the principal branches of agricultural engineering.

Digitized by

Google

PART ONE— SURVEYING

CHAPTER I
AGRICXJLTURAL SURVEYING

Surveying. The object of agricultural, or land, survey-
ing, in its generally accepted meaning, is to determine and
place on record the position, area, and shape of a tract of
land. The various steps taken to accomplish this end con-
stitute a survey. In addition to the field work with instru-
ments for measuring distances, angles, and directions, a
field record, containing figures, notes, and sketches concern-
ing the work must be kept; the areas must be computed; and
usually a map, plat, or profile made showing the tract of land
surveyed. The art of land surveying includes all of these
various lines of work.

Uses of Surveying. Agricultural students can well
afford to spend some time in the study of land or agricultural
surveying. The object of the work here presented on sur-
veying is to enable the student to measure and calculate
accurately the areas of the various fields of the farm and
to locate the buildings; to prepare a good map setting
forth the relative size and position of the fields, buildings,
and fences, and indicating the drains; and to prepare the
student for the study of drainage and irrigation.

It is necessary for the farmer to know the areas of his
fields in order that he may determine accurately the yields
of the various crops grown. A survey will enable the farmer
to so divide his farm into fields as to facilitate a system of
crop rotation.

Digitized by

Google

SURVEYING 17

A good map is a means of recording the location of drains
and water pipes laid beneath the sm*face of the gromid. It
will also enable the farmer to direct the work of the farm
more easily, and to make a study of the most convenient
arrangement of fields and buildings. This method is used
by architects and engineers in planning buildings and
engineering work such as factories and railroads.

Divisions of Agricultural Surveying. The work of mak-
ing a survey resolves itself into three stages or operations,
as follows:

1. Measuring and recording distances and angles, involv-
ing the use, care, and adjustment of the instruments used in
the survey.

2. Drawing the tract surveyed to a suitable scale, or
proportion.

3. Calculating the areas of the tracts surveyed.

QUESTIONS

1. What is the object of agricultural survejdng?

2. Define a survey.

3. To what use can a knowledge of surveying be put by those con-
nected with agriculture?

4. In what way will a map be of use to the land-owner?

5. Describe the three divisions of agricultural surveying.

Digitized by

Google

CHAPTER II
MEASURING; USE AND CARE OF INSTRUMENTS

Instruments for Measuring Distances. Often students
are led to think that it is impossible to make a survey without
a very elaborate equipment of expensive instruments, but
this is not true. An agricultural survey, such as is usually
required by the farm owner or manager, can be accomplished
with simple and quite inexpensive instruments. Where the
boundary of the tract of land is known, a practical survey
may be made with a surveyor's chain or tape.

Gunter's Chain. Much of the land in the United States
was surveyed originally with the Gunter's chain, which is
now but little used. This chain is 66 feet
long, divided into 100 links, each of which,
including the connecting rings at the ends,
is 7.92 inches long. The Unks are made of
steel or iron wire, and the better chains
have the open joints soldered or brazed to-
gether. The reason for making the Gunter's
chain of the length of 66 feet or 100 Unks is
pj "7*The ^^^S to its convenient relation to the stand-
Gunter*s chain, ard luuts of length and area in use. The
chain is 1-80 of a mile, or four rods. A
square chain is 1-10 of an acre. Thus ten square chains
make an acre, and this, together with the fact that links
may be written as a decimal of a chain, greatly facilitates
computations. To illustrate, 1625 square chains equal 162.5
acres, and 15 chains and 24 links equal 15.24 chains.

Digitized by

Google

SURVEYING 19

The Gunter's chain has been used on all United States
land surveys; and in deeds of conveyance and other legal
documents, when the word chain is used, the Gunter's
chain of 66 feet is meano.

Table of Linear Measure.

12 inches (in. or ") make 1 foot (ft. or ')

3 feet " 1 yard (yd.)

63^ yards or 16J^ feet ■ " 1 rod (rd.)

320 rods " 1 mile (mi.) .

Equivalent Table
Mi. Rd. Yd. Ft. In.

1 320 1760 5280 63360

1 514 16J^ 198

1 3 36

1 12

Table of Gunter's Chain Measure.

7.92 inches (in. or ") make 1 link (li.)

100 links " 1 chain (ch.)

80 chains " 1 mile (mi.)

Equivalent Table
Mi. Ch. Li. In.

1 80 8000 63360

1 100 792

1 7.92

Table of Surface Measure.

144 square inches (sq. in.) make 1 square foot (sq. ft.)
9 " feet " 1 " yard (sq. yd.)

30Ji " yards *' 1 "rod (sq. Ixi.)

160 " rods " lacre

Equivalent Table

Sq.rd.

Sq. yd.

Sq.ft.

Sq. in.

160

4840

43560

6272640

30 Ji

272K

39204

9
1

1296
144

Digitized by

Google

20 AGRICULTURAL ENGINEERING

Surveyor's Measure.

625 square links (sq. 11.) make 1 square rod (sq. rd.)
16 '' rods " 1 " chain (sq. ch.)

10 " chains " 1 acre

640 acres " 1 square mile, or one section

Equivalent Table

Sq. ch. Sq. rd.

Sq. li.

10 . 160

100,000

1 16

10,000

625

Cloth and Metallic Tapes. Tapes made of linen cloth
are not practical to use in land surveying, even when well
made and water-proofed. They will stretch when pulled up
tight, and are difficult to handle in the wind. A cloth
tape is much improved when small brass wires are woven
lengthwise into it to check the tendency to stretch. Such
a tape is said to be a metallic tape. These tapes are made to
wind into a case of sheet metal or leather, and for this reason
are very convenient to carry about.
Steel Tapes. The steel tape is
now the standard measuring in-
strument, as it has many advan-
tages. It does not kink, stretch, or
wear so as to change its length.
The steel tape may be obtained in
lengths varying from 3 feet to 1000
feet. These tapes may be marked
Figr. 2. A metallic tape, or graduated in any form desired.

This tape has brass or cop-

per wires woven into it The tWO COUmiOU mcthodS Of

marking the tape are by either
etching the surface with acid, or stamping the marks on
solder placed on the tape at the desired places. A tape

Digitized by

Google

SURVEYING 21

100 feet long is usually tenned the engineer's tape, and
either this length or the 50 foot tape is the most convenient.

The average width of
the steel tape is 5-16 of
an inch, and the thick-
ness about .02 of an inch.
Short tapes are arranged
to be carried in metal or
leather cases, but longer
tapes are carried either

on reels or are "thrown" ^'^' '' ^ '^''' ^"'^^ ^°""^ ^'^ ' ^^*'^-
into a coil from which they can be unwound without danger
of kinking.

Arrows, or Marking Pins. For mark-
ing points temporarily while measuring with
a tape or chain, arrows, or marking p^ns,
are used. These are made of stout wire,
pointed at one end, with a large eye or ring
at the other. In order that the pins may
be easily found in the grass or leaves, a
piece of colored cloth should be tied to the
rings. Eleven pins are required for a com-
plete set, and are best carried on a ring
Pig. 4. Arrows, with ^ Spring catch.

^"^ ^*"^* Range Poles or Flagstaffs are used to

locate points in establishing a line. They are rods or poles
usually 6 to 10 feet long, made of wood or iron, pointed
so as to be easily planted in the ground, and painted red
and white alternately in foot sections.

Flagstafifs should be placed directly over the points they
are to mark, and great care should be used to plant them truly
vertical. Much skill may be attained by practice in estab-
lishing lines with flagstaffs, and this skill will be found very
useful in laying out fields, fences, etc.

Digitized by

Google

22 AGRICULTURAL ENGINEERING

The Care and Use of Chains and Tapes. The cham is
folded by starting at the middle and folding in the two halves
at the same time. It is opened by holding the two handles
in one hand and throwing out the chain with the other.
The steel tape is wound on a reel or thrown into a coil, the lat-
ter method requiring some practice and skill to prevent kinks.
I Chains and tapes are used in measuring

horizontal distances; and for this purpose they
should be held horizontal, or level, when meas-
uring, not parallel to the surface of the ground.
The chain or tape should be pulled taut enough
to overcome the shortening due to the sag.
Where distances are to be obtained with great
accuracy, the chain or tape should be tested
often over a known fixed distance to determine
the amount of pull necessary to bring it to

■ the true length. Chains in constant use re-

quire frequent adjustment for wear.
Each pin should be so placed that its thick-
ness will not be added to the length of the chain.
Care should be taken to set the pins vertical.
When chaining up or down slopes, one end of the
chain must be held high to make it level, when it
becomes necessary to transfer a point from the
elevated end vertically to the ground. This can
^,^ g best be done with a plumb-bob and string, and
^"J^fe" when this is not at hand a pin may be dropped
from the elevated end of the chain or tape and
the point where it strikes the ground noted.

In chaining practice, the man leading is called the head
chainman, and the other the rear chainman. In beginning
a measurement, the rear chainman marks the starting point
with one of the eleven pins in the set, and gives the remain-

Digitized by

Google

SURVEYING 23

ing ten to the head chainman, who counts them. The head
chainman then leads away with the chain or tape toward the
point to which the distance is to be measured. When the
rear end of the extended tape is near the starting point, the
rear chainman calls "chain" or "tape," as signal for the head
chainman not to go too far. The chain is then stretched full
length, and the rear chainman hnes the front chainman with
the objective point by motioning with his head or other-
wise indicating the direction he should move. When the
head chainman has the chain in Une, the rear chainman calls
"stick," indicating that he has the chain to the pin. The
head chainman then pulls the chain tight, and sets a pin,
calling "stuck." The rear chainman pulls the rear pin,
and both men move ahead and repeat the operation from
the second pin; and so on. When the head chainman has
placed his ten pins, he calls "tally," and waits for the rear
chainman to walk forward to him and give him the ten pins
he has collected.

Pacing. The ability to estimate distances accurately by
pacing is often useful. Skill may be developed by pacing
known distances imtil the length of the individual pace is
determined and can be regulated.

QUESTIONS

1. What instruments are needed in making a practical survey of a
tract of land where the boundaries are known?

2. Describe the Gunter's chain.

3. Recite the four tables used in measuring surfaces.

4. Describe the differences in tapes.

5. Describe the use of range poles. Of marking pins.

6. How is the chain cared for? The steel tape?

7. Describe the process of chaining.

8. In what way will the ability to estimate distances by pacing
be useful?

Digitized by

Google

CHAPTER III

FIELD METHODS

Making Chain Surveys. For many practical purposes a
survey made with the tape or chain alone will be quite
satisfactory. To make such a survey for area, the land
is divided into rectangles or triangles, or both. The areas
of any of these may be easily calculated when the length of
each side is known.

Making Notes. In all surveys, all figures, notes, and

sketches should be sys-

B€

SURVEY OF FIELD

140
/SO
BOO
850
ISO
110
ISS

ABCO WITH TAPE

Head chohman R.Roc
Rear chainmon I. Doe

Sept. I ion - J Ars.
Cloudy an J cool

Used stflfape too ft.

Measured each side

in turn once

tematically recorded in a
suitable book, and these
go to make what is called
field notes. From these
notes the map is later
made and the areas cal-
culated.

The most simple
method of making field
notes is to make a free-
hand sketch of the field
as nearly correct as the
eye can determine. All
comers should be designated by letters and the same
marked on the sketch, which is used as a guide. All
distances between comers should be recorded, not only
in the sketch, but also in suitable columns. The points
where fences, streams, and roads are crossed in measurement
should be noted on the sketch. If the tract surveyed is so
large that the sketch is likely to become confused, the entire

Flgr. 6. A form for Held notes.

Digitized by

Google

SURVEYING

tract may be sketched on one page, and details of certain
parts on other pages.

All field notes should be carefully recorded in a well-
bound, durable, and convenient field book. The standard
field book has pages about 4 by 7 inches, ruled in any one of
the several forms of ruling, and is substantially bound.
The notes should be neatty made with a hard pencil in order
that they will not blur with use. In the sketches, the cus-
tomary sjrmbols employed in map making may be used.
These will be described later.

Field Methods. In making a chain survey, it is to be
remembered that, since angles are not measured, more meas-
urements will be required. Many fields are rectangular,
and their measurement is correspondingly simple. When
the angles are not right angles they may be determined by
measuring three sides of a triangle laid off in the comer,
making two sides or the legs of the triangle coincide with the
sides of the field.

Marking Points in a Survey. In making a survey all the
important points should be marked for future reference. In
laying out fields and lots, some permanent mark should
be set at the comers. If a comer
post is not used, a stone or a
block of concrete should be set in
the ground and a cross chiseled on
the surface to indicate clearly the
point. Stakes of durable wood may
be used to good advantage. The
exact point may be indicated by driv-
ing a tack in the top of the stake. A
stake two inches square is often
used. The field notes describing the
location of these points should be

Fig. 7. Sketch showing
how a line may be laid off
at right angles to another
at a point A.

Digitized by

Google

26 AGRICULTURAL ENGINEERING

complete and clear enough to make it easy for anyone to find
the comers again at some future time.

PROBLEMS FOR PRACTICE

(In order to carry out the following problems it will be necessary
to be provided with equipment consisting of tapes, pins, and range
poles.) '

1. With chain and range poles lay off a right angle.

Note, 3, 4, and 5 feet, or corresponding multiples of these dis-
tances, are sides of a right angle triangle. Give the theorem of geometry
upon which this is based. (Fig. 7).

2. Measure the distance between two points a thousand feet or
more apart and check with the results obtained by the instructor.

RandoM^ Ltne

True Lme

Fig. 8. Sketch showlngr method of locating points on a desired line
between two points not visible from each other from a random line.

3. Let each student pace this or some other known distance and
determine the length of his pace.

4. Estimate certain distances by pacing, and then measure accu-
rately with a steel tape.

5. Chain over a hill between two points not visible from each
other.

Range poles should be set at the points and then the chainmeA
with range poles should take such positions on each side of the hill as
will enable each to see over the hill and past the other chainman to
the range pole beyond. The chainmen then range each other in, mak-
ing several trials.

6. Chain between two points when the view is obstructed by woods
or other objects.

To accomplish this, run a trial or random straight line as near as
possible to the distant point, leaving fixed points at known distances.
Upon finding the error at the terminus, correct all other points into
line a proportionate amount. Then the desired line may be chained.

Digitized by

Google

SURVEYING

7. Determine the distance to a visible but inaccessible object.
Use two similar right-angled triangles. Fig. 9.

8. Prolong a line beyond an obstacle.

There are several ways to accomplish this, but the use of similar
triangles is the only method suggested.

Let A B be points in the line to be prolonged beyond O, an obstacle.
Make A B C a right-angled triangle. Prolong A C to F, making C F
equal A C, and C E equal E F, and B C equal C D. Extend D E to I,
making DG and G I equal to A C,.also
extend F G to H, making G H equal F G.
Then H I are points in the extended line
AB.

ease

Fig. 9. Sketch showingr
method of measuringr to an
inaccessible point.

Flgr. 10. Sketch showing method of extend-
ing a line beyond an obstacle.

9. Make a survey of the lot on which the schoolhouse stands,
locating buildings, etc.

10. Make a survey of the home farm or a part of it, as assigned by
the instructor.

11. Make a survey of a lot or a field having an irregular side, by
taking offsets at regular or irregular intervals, dividing the field into
trapezoids. (See method of calculating areas of tracts with irregular
sides).

QUESTIONS

1. How is a tract of land divided in making a chain survey?

2. What care should be taken in making field notes of a survey?

3. What care should be taken in marking permanent comers?

Digitized by

Google

CHAPTER IV
MAP MAKING

Uses of a Map. When a survey of a farm or other tract
of land has been made, a map should be drawn to show the
location of the buildings, fences, lots, roads, and of the trees,
streams, and other physical features of the land. A map
enables the mind to grasp the facts in a way not possible
with the field notes alone. Although not generally practiced,
a good map of the farm can be used advantageously in
directing the work of the farm. This map should also serve
as the means of recording the location of drains and water
pipes placed beneath the surface of the ground. If the fields
are numbered and the map placed in the office or dining
room of the home, it may be used as a basis in planning each
day's work. The map will set also forth in a very forceful
way any inconvenience in the arrangement of the buildings
or fields.

The Final Map. The final map is made from the data
recorded in the field book. As has been said, a sketch map
usually forms a very helpful part of the field notes. The
final map must be drawn carefully as well as accurately,
and should be made as durable as possible.

Drawing Instruments. The equipment for making maps
may be quite extensive, yet the essential instruments are not
many in number nor are they expensive. A good outfit
includes the following: A drawing board of soft wood and
about 20 by 30 inches in size, a T square, a triangle, a scale
providing at least 10 and 50 divisions to the inch, a ruling
or right-line pen, a compass for drawing circles, a bottle of

Digitized by

Google

SURVEYING

India ink, and a pen, a pencil, an eraser, thumb tacks, etc.
A bottle of carmine ink is convenient but not necessary.
When angles are to be plotted a protractor is quite necessary.
A good quality of drawing paper should be used, or one
that will stand reasonably hard usage in folding and handling.
A good quality of paper is known as bond paper, and a con-
venient size of sheet is 18 by 24 inches. A drawing made on
this bond paper may be reproduced by blue printing, a
process similar to the making of photograph prints from

nizn

)

-^ ~o.

Figr. 11. A set of drawing instruments, consistlngr of a drawing
board, a T square, a triangular scale, two triangles, a protractor,
a case of instruments, an Irregular curve, paper, ink, tacks, etc.
This fift Is more complete than is required for map making as indi-
cated in text.

negatives. The process is rapid, requiring but a few min-
utes, and the cost of the blue-print paper is but a few cents per
yard. A better print can be obtained, however, from a
drawing made on tracing cloth, which is thin and so prepared
as to make it practically transparent. Where expensive

Digitized by

Google

AGRICULTURAL ENGINEERING

maps are to be prepared, one of the heavy, serviceable papers,
like Whatman's hot-pressed paper, is desirable.

Making fhe Map. In making a map, the proper scale
to use, that is, the ratio between the actual distances in the
surveyed tract and corresponding ones for the map, must
first be decided upon. In the case of an average-sized farm,
100 or 200 feet to the inch is a convenient scale. The larger
the area or the smaller the maps the greater will be the dis-
tance represented by one inch on the map. If the scale,
(meaning the instrument used for measuring) be graduated
so as to give 50 divisions to the inch, it will be easy to use

with any of the ratios proposed.
For instance, suppose the ratio of
100 feet to the inch be adopted,
then one division on the scale will
represent 2 feet; and if 200 feet be
adopted as a ratio, then one divi-
sion will equal 4 feet, etc.

The handling of the drawing
instruments mentioned is simple.
The head of the T square, when
held by the hand against the
straight edge of the drawing board,
will permit the drawing of parallel
By holding the triangle
sides being given. agaiust the blade of the T square,

all vertical Unes may be drawn accurately. The ruling or
right-hne pen is used in drawing straight lines on the final
map with the India ink.

The first operation to perform in preparing a map is to
lay off the boundary of the tract to be mapped. Then the
location of other features may be added. Angles may be
plotted in by the use of the protractor, if angles have been

Fig. 12. Laying out a tri- li-n^iQ
angle, the length of the three "^^^»

Digitized by

Google

SURVEYING

read. The use of instruments for measuring angles will be
described later. If measurements have been made to
determine angles, these angles may be laid out with the aid
of the compass, setting this instrument with the scale and
describing circles whose radius is equal to the length of the
sides of the triangle. The map should first be made with a
pencil, and then, after every feature has been drawn, should
be inked in.

Common Topographical Signs. A topographical map is
one which gives the general character of the land surface.

aingleTrcKk.

Ooubto -nraok.

Streom.

Pail ways.

000000
000000

CultivqtedLcsnd

windbreak.

mk. SK ttm im

«». 4h. «ta. «»
«k •» «b <*i

^ O O O

a Q O O
<^ (B O O

Mocod. Qood

99O0ndry -
Privot« or Form.

Wira fancm.

Wck«r- -

Poada.

Doundariea

Contour

Lawn.

Orchard.

DeciduousTreea. ^y/ergreon^

Fig. 13. Conventional topographical signs.

showing where there are roads, buildings, forests, swamps,
etc. To facilitate the making of such maps, it is customary
to use certain symbols or methods of representing certain
conditions of the surface. A general use of certain symbols
to indicate certain things has resulted in their being known

Digitized by

Google

32 AGRICULTURAL ENGINEERING

as conventional topographic signs. It is not sufficient, how-
ever, that these conventional signs alone be used, but should
be supplemented with notes.

Lettering. Maps made by professional draftsmen or
engineers have all notes and titles neatly lettered in. The
ability to do lettering quickly and neatly is a part of the train-
ing of the engineer. Letters for titles are often made by the

oi bcdet ghijklniho pqrstuvv/X y z
/aJ4567890
ABCDCrGHiJKLMNOPQRS TUV WX YZ
Inclihed Leiferihg, for Descripficn^

abcdefghljklmnopqr c+uvna/ xyx

ABCOET GH UK LMN OP QR5TUVWXYZ
1234567890
Upright Lettering, for Captions.

Fig. 14. Good styles of free-hand lettering.

use of instrmnents, but on most maps the letters must be
made with a form of the writing pen, the only instruments
used being the T square and triangle with which the guide
lines are drawn, to assist in making the letters even and of
uniform height. While it is not best to attempt to duplicate
the work of the professional engineer, it is desirable that all
maps be of as neat appearance as practical; and few things
add to or detract from the appearance of a map quite so much
as lettering. The best lettering is that which is simple and
easily and quickly made. A good alphabet is furnished in
Fig. 14, and is a form of lettering now in general use. The
beginner should first pencil the letters on the map; and when

Digitized by

Google

SURVEYING

an arrangement of the notes is found which is adapted to the
map, they should be traced with drawing ink. Although
not absolutely essential, it is suggested that all maps be
lettered in the customary way.

r/eM Na 1

Field Ne.e

J5.A

35 A

Pashte

ISA

Field Na J

Field No. 4

35. A

35 A

^r»

U hs

Figr. 15. A farm map.

QUESTIONS

1. In what way may a farm map be used?

2. What is the purpose of a sketch map?

3. What drawing instruments are necessary for map making?

4. What kind of paper should be used in making a map?

5. Describe the making of a map.

6. What is the use of conventional topographical signs?

Digitized by

Google

CHAPTER V
COMPUTING AREAS

Method of Computing Areas. One of the primary objects
in making a farm survey is the determination of the areas of
fields and plats. The computation of areas as here described
is dependent upon a knowledge of mensuration and geoiiietry.
The general plan to be followed is to divide the tract into
simple or primary figures whose areas can be easily calcu-
lated. These familiar rules of mensuration will now be
reviewed.

Rectangles. If a tract of land is rectangular in shape,
its area is found by multiplying its length by its breadth.
Triangles. If a piece of ground is in the form of a tri-
angle, its area may be obtained by either of the following
rules: (1) If the length of one side, and the perpendicular
distance from this side to the opposite angle, or the altitude
of the triangle, are known, the area is one-half the product
of the known side as the base, times the altitude. (2) If all
three sides of a triangle are measured,
then the area may be obtained by
adding the lengths of the three sides
and dividing the sum by two; from
Fig. 16. this half sum subtract the length of

each side in turn; multiply together this half sum and the
three remainders; the square root of the product equals the
desired area. Thus, if a, 6, and c are three sides of a triangle,

, a + b+c ^,
and s = ^ , then

area =1/8 (s-a) (8-6) (a-c)

Digitized by

Google

SURVEYING

Pig. 18.

Parallelogram. (Fig. 17.) The
area of a parallelogram, a four-sided
figure with opposite sides parallel, is
equal to the product of one of its sides pi^. 17

and the perpendicular distance be-
tween it and the opposite parallel side.

Trapezoid. (Fig. 18.) This is a

four-sided figure with two sides par- / I

allel. The area is equal to the pro-
duct of one-half the sum of the parallel
sides by the perpendicular distance between them.

Area -^Xh.

where a and b are the two parallel sides, and h the perpendicular
distance between them.

Trapeziums (Fig. 19) are quadrilateral figures, no two of
whose sides are parallel. A practical
way to obtain the area of a field of
this shape is to measure a diagonal
dividing the field into two triangles
whose areas may be calculated. It
is to be noted that averaging opposite
sides and taking their product will
not give the area.

Area abcd = area ACD+area abc.

Figures With Many Sides. First
Method: (Figs. 20 and 21.) A many-
sided piece of land may be likewise
divided in triangles and its area ob-
tained in the way described for tra-
pezium. The triangles may be formed about one of the
comers of the figure, or about a point wholly within the

Fig.

Digitized by

Google

AGRICULTURAL ENGINEERINa

Fig. 21.

r^_ ^,.JUl-_-L/ — |/

area. It is to be noted that if a point within is taken as

the apex of all the angles, it would
be necessary to measure, either all
three sides of each separate tri-
angle, or one side of each as a base,
and the altitude.

Second Method: (Figs. 22 and
23.) The area of a many-sided
jfigure may be obtained by dividing
the field into parallelograms formed
by dropping a perpendicular from
. each comer to a base line projected either across the field or

on one side. It is to be
noted that all parallelo-
grams which are entirely
outside of the field are
negative areas, and their
sum should be subtracted
from the sum of those
having a part of their area inside
of the field.

Figures With Irregular
Sides. First Method: The area
of a field with an irregular side
like that formed by a stream
may be obtained by considering
the irregular side to be formed
of short straight Unes, and
measuring offsets, or per-
pendiculars erected from
a base Une to points in this
broken line so as to form

Fi«r. 22.

Figr. 23.

Fi«r. 24.

trapezoids, whose areas are easily found.

Digitized by

Google

Fig. 25.

SURVEYING 37

Second Method: If the
side of the irregular field
is not of such a character
as to be readily divided
into large trapezoids, then
the offsets may be taken
at regular intervals along the base line.

If d be the regular intervisd between offsets then the area of the
trapezoid whose sides are h and ^ ' is equal to one-half their sum mul-
tiplied by d, or

Abea abcd = J^ (^+^0

PROBLEMS

1. What is the area in acres of a rectangular field whose length is
1320 feet and whose width is 347J^ feet?

2. How many acres in a field 80 chains long and 13.25 chains wide?

3. What is the area in square feet of a triangular piece of ground, if
the length of one side is 339 feet and the altitude on this side as a base is
92 feet?

4. The length of the sides of a tract of land in the form of a tri-
angle are 220,310, and 343 feet. What is the area in acres?

5. The four sides of a trapezimn are 420, 417, 380 and 375 feet
taken in order around the field, the diagonal from the comer between
the 417 and the 380 foot sides to the opposite comer is 528 feet. Find
the number of acres in the tract.

6. Find the acre area of a road 66 feet wide and 3960 feet long.

7. Find the area in square feet of a tract of land with an irregular
shaped side if offsets taken at the regular interval of 50 feet are 0, 25,
30, 28 and 60 feet, respectively.

8. How many rows of com 3 feet 6 inches apart can be planted in
a field 20 rods wide? How many hills of com 3 feet 6 inches apart will
there be in the field if it be 80 rods long?

9. How many apple trees 20 feet apart may be planted in a 1-acre
tract in the form of a square? Try a different arrangement of the trees.

10. At this point the student should be prepared to take up the
problem of siu-veying, mapping, and calculating the area of cert^
tracts of land, as the school house yards, lot, field, or even whole farms

Digitized by

Google

CHAPTER VI

efri'C*'at4

T.4N.
R.4W

T.3N.
R.4W

T.3N.
RAW.

TIN.
R.4W.

T.4N.
R.3W.

T.3N.
RJW.

T3N.
R.JW.

TIN.
R.3W.

'J£SL,

THE XJNITED STATES PUBLIC LAND SURVEY

In order to facilitate the survey, location, and designation
of the lands in the United States, Congress in 1785 adopted
a system since known as the United States Rectangular
System of Public Land Surveys. This system has been
modified from time to time, but remains substantially as
first adopted. The earth's surface is like that of a sphere,
and it would be expected that in attempting to lay out the
surface into rectangular areas one would encounter many
difficulties. Yet these difficulties have been very satis-
factorily met.

The squares of this system are bounded on the east and
west by true meridians of longitude, radiating from the

north pole, and on the
north and south by
chords of parallels inter-
secting such meridians.
A principal meridian
is chosen in each land
district, and from this
meridian a base line is
run east, west, or east
and west, from what is
called the initial point.
Standard parallels are
run east and west from
the principal meridian at
These standard parallels are often

T4N.
R.SW.

T3N.

R.aw.

T.SN.
R.3W.

TIN.

R.a W. R.I VSA

T4N.
RJW.

T3N.
R.IW.

T.SN.
RJW.

TIN.

Base Line

Initial Pcinf

Fig.

26. Showlngr the division and num-
bering: of townships.

intervals of 24 miles.

Digitized by

Google

SURVEYING

called correction lines. Guide meridians are run north from
the base Ime and from the standard parallels at intervals of
24 miles. These blocks of land are successively divided
into townships six miles square and then into sections ap-
proximately one mile square.

Townships. The townships lying between two consec-
utive meridians six miles apart constitute a range, and the
ranges are numbered from the principal meridian, both east
and west. The townships in each range are numbered
both north and south from the base line. Thus if a town-
slip lies 18 miles west
of the principal meridian
and 12 miles north of
the base Une, it is de-
scribed as Township
(Twp.)2N., RangeSW.
Sections. Each town-
ship is divided into 36
sections of 1 square mile,
or 640 acres more or less,
the exact areas being
subject to the conver-
gence or divergence of
the meridians, which
amounts to about a foot for each mile.

Sections in all of the more recent surveys are numbered,
beginning with the section in the northeast comer of the
township as No. 1, and proceeding as indicated in Fig. 27.

Subdivisions of Sections. Each section may be divided
into one-fourth section, or 160 acres, or into still smaller
divisions of 80, 40, or 10 acres. Each of these divisions may
be described by its location in the section. Thus a quarter
section of 160 acres may be the N.E.J4, S.E.Ji, S.W.^, or

14-

M4-

£9

£$'

e€

Jtf

Pig. 27.

The numbering of the sections
in the township.

Digitized by

Google

AGRICULTURAL ENGINEERING

the N.W.)^ of Sec.— Twp.— Range— . An 80-acre tract

may be the E.3^, W.J^, S.3^, or N.3^ of etc. The 40-

acre and smaller tracts may be described in a similar manner.
Monuments. . In making the original smreys, the gov-
ernment surveyors left what are called monuments to mark
the location of principal comers. These monuments were
usually made of stone with suitable marks to identify them,
but in some instances only wooden stakes or heaps of earth
were used.

SurvejTS by Metes and Bounds. Before the adoption of

the rectangular system of
land surveying, the lands in
the United States were sur-
veyed by describing fully the
boundaries, and it was not
practical to change to the
new system where land had
been so surveyed. This sys-
tem is still used to a certain
extent to describe small
tracts of land even when the
rectangular system might be
used.

ResurvejTS. It is not the purpose of this text to include
directions for surveying units larger than the farm, and it
does not attempt to give directions for a resurvey of the loca-
tion of the comers of a certain tract, yet some of the impor-
tant features of such a survey may be mentioned.

One of the most important considerations is that when the
boundaries of the pubUc lands established by the authorized
government surveyor are approved by the surveyor general,
and accepted by the government, they are unchangeable.
This is tme whether the comers were located where they

f^Wi

lOA

40 A.

t60 A

SiNCk
SOA

S0C.I

T4UR.IW.

0 A

Fig. 28. Divisions of the section.

Digitized by

Google

SURVEYINa 41

were intended to be or not. Future surveys may be made
to further subdivide the tract, but as long as the original
comers are known, no additional surveys can change them.
If the corners become lost, a resurvey may be made to locate
them, not where the comers ought to be according to the
system, but where they were first located. There are many
considerations and points to be taken into account in the re-
storation of lost and obliterated comers and subdivisions
of sections, and it is advised that this be left to the pro-
fessional and authorized surveyors.

QUESTIONS

1. What was the purpose of the United States rectangular system
of public land survey?

2. What is the general plan of this survey?

3. Explain how the land is divided into townships and sections.

4. How are townships numbered?

5. How are sections niunbered?

6. Explain how sections are divided and the parts described.

7. How were comers marked in the original survey?

8. Describe the process of surveying by metes and bounds.

9. What is the purpose of a resurvey?

Digitized by

Google

CHAPTER VII

mSTRUMENTS FOR LEVELING

So far our discussion has been confined to instruments
used for measuring horizontal distances, or those necessary
to obtain areas. In farm practice, however, it is necessary
in connection with drainage practice, road construction, etc.,
to determine vertical distances, or the height of one point
above another even though these points be at some hori-
zontal distance from each other.

DEFINITION OF TERMS

A level surface is one that is perpendicular to a plumb
line at every point in the siuf ace. It is not a plane nor is it
a true oblate spheroid, owing to the fact the earth is not a
homogenous body and the center of mass does not conform
with the center of form.

A level line is one that lies wholly within a level surface.

A leveling instrument is one by which a level plane or a
level line may be accurately determined. The three appli-
ances upon which leveling instruments depend are the plumb
line, a tube filled with liquid, and the bubble tube*.

A datum plane or a datum is the initial plane to which the
height or elevation of points may be referred. A datmn
plane in common use is that of sea level.

The elevation of a point is the distance of the point above
or below the datiun plane.

A leveling rod is a graduated measuring rod or staff
used for measuring vertical distances between a point on
which the lower end of the rod may rest and a line indicated

Digitized by

Google

BURVEYINa

by an instrument. A leveling rod which has a sliding disk
or target which may be raised or lowered imtil the center lies
in the line indicated by the leveling instrument, is called a
target rod. A rod which may be read from
a distance or from the leveling instrument
is a speaking rod.

Leveling rods are graduated to feet, and
tenths and hundredths of a foot. In work
requiring extreme care, the target may be so
made as to be read to one-thousandths of a foot.

Bench marks « are permanent objects
whose elevations are known or assumed,
and which may be used as reference marks
for the elevation of other points.

The Plumb Line. The plumb Une is per-
haps the simplest and most generally used
of the leveling instruments. Even the most
expensive instruments use the
plumb Une to locate the instru-

, J. ,, . . , FIff. 29. Level-

ment directly over a given point, ing rods: the one
Provisional levels may be taken Son-spel!dng io^
by means of a combination of the n^^\o^; a?d
plumb line and steel carpenter's i^A is a*spe"aking
square, and the difference in ?S',SS,r ''''*
the elevation of points not far
apart may be thus obtained. This instrument
may be used not only in laying drains but
also in road construction to determine the grade
of the road and the slope to the side ditches.
The U Tube or Water Level. This instru-
ment depends upon the principle that a liquid "seeks its
level." It consists in two glass tubes fastened vertically
about three feet apart on a suitable arm and connected with

Digitized by

Google

AGRICULTURAL ENGINEERING

Corks fo be

Used When

Levei is Carried

a tube. Water is then poured in until it appears at a con-
venient height in both glass tubes at the same time. The
surface of the water in each of the two tubes gives two points

in a level line, which may
be extended to a distant
leveling rod by sighting
over the surface -pf„ the
hquid.

A water level may be
made as shown in Fig. 31 ;
A and^JS are short lengths
of glass tubing attached
to a board, about three
feet apart, and connected
on the lower sides with a
length of rubber tubing.
For field use, the board
is bolted to a staff which
may be pushed into the
ground to hold the instrument erect, and corks are provid-
ed for the upper ends of the tubes to prevent loss of the
liquid while the instrument is being carried. When leveling,
these corks should be removed.

The bubble tube is the basis of nearly all leveling
instruments. It consists of a round glass tube bent so that
the upper inside sur-

face is an arc of a — ^^si^g^^^'S^ fUi^^yls^^
circle lengthwise, or
on a longitudinal sec-
tion. This tube is

sealed at each end and nearly filled with ether, the
remaining space being filled with the vapor of the liquid.
The upper surface of the tube is usually graduated

Fig. 81. A home made water levet

FIgr. 32. A bubble tube.

Digitized by

Google

SVRVEYINa 45

or marked to indicate clearly the position of the bubble
in the tube.

If the inside of the bubble tube is truly circular length-
wise, then as the bubble tube is held so as to bring the con-
vex side of the tube up, it is plain that the bubble will come
to the highest point. This being the case, a line tangent to
the curvature of the tube at this point is a level line regard-
less of the part of the tube in which the bubble may lie.

If the bubble tube is attached to a frame and placed on
two supports and one of these supports is raised or lowered

until, as the frame is
reversed on the supports, the
bubble will occupy the same
position, these supports are
^. •• . * ^ 1 , i*K both in a level line, provid-

Flgr. 33. A carpenter's level with , , . ', . , .

sigrhts attached. mg the identical points m

the frame come in contact with the supports in each case.
Furthermore, the points on the frame will be in a level line
when the bubble is brought into the position described.

Thus the carpenter's level, used for leveUng buildings, is
made. If sights are provided on the level, the level Une so
obtained may be extended to a greater distance. A line
tangent to the bubble tube
on its inner surface at its
center as indicated by the
marks on the tube is known
as the bubble axis. If the
bubble tube be revolved
about a line perpendicular
to the bubble Mis, the bub-

, , . Ml J 'U 1 1 ^*fif' 84. An inexpensive farm level

Die axis Will deSCnbe a level with horizontal circle for turnlngr off

£ ansrles.

surface.

The Level. The instrument used generally by en^neers

Digitized by

Google

4« AGRICULTURAL^ ENGINEERING

for determining the difference of elevation between two
points is known as the level, and involves primarily the ele-
ments just described, — the bubble axis, a line of sight paral-
lel to the bubble axis, and a vertical axis perpendicular to the
bubble axis about which it may be revolved.

To assist in extending the line of sight, leveling instru-
ments are provided with telescopes. The sights in this case
are provided by cross wires or cross hairs set in the tele-
scope.

Fig. 35. A level known as a Wye Fig. 36. A "dumpy" leveL

level with horizontal circle and com-

THE ADJUSTMENTS OF THE LEVEL
The Need of Adjustment. Accurate and rapid work
cannot be done with a level unless it be in proper adjustment.
Even the best instruments will not remain in adjustment
indefinitely, and tests of their condition should be made often.
In practice some of the best engineers make it a rule to test
their instruments every day. Everyone who uses a level
should know how to test and adjust it. Its adjustment is not
a difficult matter, yet it requires some study to master the
methods used. Every instrument maker of repute will fur-
nish full and complete directions for adjusting each instru-
ment of his manufacture, and these directions should be
given preference over general directions applicable to all

Digitized by

Google

SURVEYING 47

instruments. There is more than one method of makinjg
certain adjustments, but only one will be explained here.

As has been stated, there are three elements in a level
which should be kept in proper relation: namely, the vertical
axis, or the line about which the instnunent can be rotated;
the bubble axis, which is a level line; and the line of sight.
The last two must be parallel, and the first perpendicular to
both. If the line of sight be inclined upward, it is obvious
that all rod readings will be too great, and the error will be
proportional to the distance of the rod from the level. If the
line of sight be inclined downward, all readings will be too
small. If the length of sights, or the distance between the
level and the stations, be equal in making front and back
sights, the error in each case will be the same, and the rela-
tive elevation of the stations will be obtained without error.
For this reason it is desirable to make fore sight and back
sight distances equal.

The adjustment making the vertical axis of the level and
the bubble axis perpendicular, is a matter of convenience,
for this will cause the line of sight to describe a plane con-
taining all the level lines through the instrument. This
means that it will not be necessary to change or "level up"
the instrument in sighting in different directions.

First Adjustment To make the vertical axis of instru-
ment perpendicular to the bubble axis:

Adjust the bubble tube to the vertical axis as follows:
Level up the instrument, bringing the bubble to the center
of the tube, turn the telescope through 180 degrees,
and, if the bubble changes position, raise or lower the
adjustable end of the tube until the bubble is brought half
"way back to its former position. Level the instrument
again and repeat the operation; and if the bubble moves in
the tube, make further adjustments. Continue this process

Digitized by

Google

48 AGRICULTURAL ENGINEERINO

until the bubble does not move in the tube as the telescope
is turned about the vertical axis.

Second Adjustment. To make the line of sight parallel
to the bubble axis:

Select a level piece of ground for the work, and locate
three points in a straight line, 100 feet apart. At one end
point (Sta. A) drive a hub, at the mid-point locate the level
and take a reading on a rod held on the first hub with the
instrument carefully leveled. Turn the instrument in the
opposite direction, and, after leveling carefully, drive a hub
at the second point (Sta. B) until the same rod reading is
obtained as at Station A. These two stations now have the
same elevation, because any error of the instrument will be
the same in both cases. Now bring the instrument near
Station A (two or three feet off) and adjust the line of sight
until the same rod readings are obtained on both stations.
The rod on Station A may be read by looking through the
instrument in the reverse way and locating the line of sight
on the rod with the point of a pencil. After adjusting, the
operation should be repeated as a check.

QUESTIONS

1. Define a level surface. A level line. A leveling instrument. A
datum plane.

2. What is meant by the elevation of a point?

3. Describe a leveling rod. What is the difference between a
speaking and nonnspeaking rod?

4. How are leveling rods graduated?

5. What is the purpose of a bench mark?

6. Describe the plumb line. How may it be used to determine a
level line?

7. Describe the construction of the water level.

8. Describe the bubble tube and its use in leveling.

9. Describe the construction of the engineer's level.

10. What is meant by the ''line of sight"?

11. Describe the fundamentals of the adjustment of the leveL

Digitized by

Google

CHAPTER VIII
LEVELING PRACTICE

DifFerential Leveling. Differential leveling is the name
given to the process of finding the difference of elevation of
two or more points at some distance from each other, with-
out reference to intermediate points except those required
temporarily in carrying a line of levels between the points
whose difference of elevation is required. Differential
leveUng is like profile leveling, except that elevations are
not taken at regular intervals on the surface. It is desir-
able, however, to make the sights or the distances between
the instnunent and rod of equal length, as this tends to equal-
ize errors which may exist in the adjustment of the instru-
ment.

Profile Leveling. Profile levehng is for the purpose of
obtaining the elevations of the surface of the ground. It is
especially important in this connection, as profile leveling
is required in the laying out of land drainage systems.

Leveling. The process of leveling, or in other words the
performance of the field work in determining the elevation
of points on the surface of the ground, is comparatively
simple, yet it is highly important that the work be done
accurately and that a full record be made of the work.

To rim a line of levels, a bench mark, or a permanent point
of reference, should be chosen from which a start is made.
The importance of the bench mark is all the more magnified
with an increase in the size of the system of levels. If the
elevation of the bench mark is not known, it must be assumed.
For convenience it is usually taken as 10, 20, or 100 feet,

Digitized by

Google

AGRICULTURAL ENGINEERING

Lin» of Ltvlg.

Sto

B
C

as.
eso

HI.

leso

1.O0 ia4o

4.0S213S

r.S. €10 y^
1000

ie.4o
a.io mo
z. 6 on. 15.

depending somewhat upon whether the levels are to be taken
above or below the elevation of the bench mark.

As for field surveying, a substantial field book should be
provided for level
notes. Abookofthe
same size as previ-
ously suggested is de-
sirable, with ruling as
shown in Fig. 37. The
elevationof the bench
mark is placed in the
second column oppo-
site the entry B. M.
in the first column.

Set the instrument up half way between the bench mark
and the first point whose elevation is desired in the line of
levels. • This point is called Station A, and is entered as such
in the first colimm of the field book. After the instrument is

Figr. 87. A form for level notes.

laoo

FiflT. 38. Sketch illustratlngr the levels of Figr. 37.

brought into a level position, the rodman holds the rod in a
vertical position over the bench mark, and the levelman takes
a reading by, over, or through the instrmnent to the rod. The
reading thus obtained is the distance of the line of sight
above the bench mark (B. M.), as the rod is graduated from
the bottom up and the line of sight is a level line. This

Digitized by

Google

SURVEYINO 51

reading is called a back sight (B. S.)i and if added to the
elevation of the bench mark will give the elevation of the
instnunent, or the height of instrument (H. I.), as generally
designated. The first B. S. thus obtained is entered in the
notes in the second column, opposite the B. M. elevation
in the first. This B. S. plus the elevation of the B. M. is
entered in the third colimm under the head of height of
instrument, or H. I.

Thus if the elevation of the B. M. be assumed as 10.00
feet, and the B. S. reading of the instrument on this point
be 6.50 feet, the H. I. will be 16.50 feet.

Now if the instrument be turned so as to extend the line
of sight in the direction of the first point in the line of levels
(Sta. A) and a reading be taken in the same way, the reading
on the rod will be the distance of the elevation of this point
below the line of sight. The reading is called a fore sight
(F. S.), and is entered in the fourth column opposite Station
A., on which the reading was taken. If this fore sight read-
ing be subtracted from the elevation of the line of sight
(H. I.), the elevation of Station A will be obtained. For
instance, suppose the F. S. reading thus obtained is 4.10
feet, then H. I., 16.50 feet, minus the F. S., 4.10 feet, equals
12.40 feet, the elevation of Station A, which is entered in the
proper column opposite Station A.

To continue the Une of levels, the instrument is moved to
a position midway between Station A, and Station B,
and, after the instrument is leveled, a B. S. reading is made
on Station A. This reading added to the elevation of
Station A gives a new H. I., from which the F. S. reading on
Station B is subtracted to obtain the elevation of Station B.

Thus the process is continued until the elevations of all
the points in the line of levels are obtained. It is easy to see
how additional readings may be taken with the same height of

Digitized by

Google

AGRICULTURAL ENGINEERING

//4&

instrument and thus obtain the elevation of several points
between A and B. This is done in practice.

It is to be noted in this connection that back sights are
rod readings on stations or points whose elevations are known,
and fore sights are readings on stations whose elevations are
i»ot known. Stations on which back sights are taken are
generally known as turning points.

Stakes. It is generally best that all stations be marked
with a stake driven down close to the groimd, on which the

leveling rod may be placed;
and turning points should
always be so marked and
identified.

Leveling a Field. It is
sometimes advisable to obtain
levels at regular intervals
over an entire field. This is
accomplished by laying the
field off into squares, usually
by the chain or tape. The
comers of the squares are
marked with stakes made of
lath and the elevation of the
top of the ground is taken at each comer, as shown in Fig. 39.
The various comers of the squares are designated by lettering in
one direction and numbering in the other as shown in the figure.
Contour Maps. Lines may be drawn over the map of
the leveled field to indicate points of equal elevation. Such
lines are called contour Unes. They offer a very satisfactory
means of studying the surface of the ground, and a map so
prepared is especially useful in laying out drainage systems.
Horizontal Circles for Levels. Many levels are pro-
vided with horizontal circles or scales, graduated in degrees

/3.0

/Sif ^|2«

/ZS

f2.3

/2.9

/20

f2/3

'/9

/2J

/22

/g./

//.S

//.r

//JO

//.S

//.a

//(^

//5-

//7

/A 7

//6

//ff

//.3

/js

//^

//s

//3

//J

//.-f

//y

Fig. 39. Plat showingr how levels
may be taken over an entire field.
The stations are indicated by letter
and numbers, as Bz, etc.

Digitized by

Google

SURVETINa 53

and fractions of degrees, which enable the angle between
lines of sight in different directions to be measured. This
de^dce is especially useful in laying off right angles, as well as
in obtaining the angle between two sides of a tract of land,
and between lines of drains in laying out drainage systems.

The Compass. A level may be provided with a compass
box containing a magnetic needle, which will enable the angle
to be measured between any line of sight and the north and
south as indicated by the needle. In construction, the mag-
netic needle is a fine hardened piece of steel carefully balanced
and hung on a deUcate pivot and so arranged as to swing
within a graduated circle. In order to protect the pivot
while the instrument is being carried about, a little device
is provided to Uft the needle from the pivot. In most
localities the needle does not point truly north and south,
inasmuch as the magnetic pole does not always lie due north;
and furthermore, the location of the magnetic pole varies
from time to time. If the true north is desired, it is neces-
sary to make the corrections for the location of the magnetic
pole. This variance from the true north, or meridian, is
called the declination of the needle. In reading the needle,
if no correction is made, it is customary to indicate that the
reading is magnetic (Mag.).

The Bearing of a Line. The direction of a line is called
its bearing; in other words, the bearing is the angle that a line
makes with the direction of the magnetic needle. If the
direction of a line, beginning with the instrument, lies within
90 degrees to the right or the left of the needle, it is said to
have a north bearing, or a northing; and Ukewise, if it hes
within 90 degrees of the true south, either east or west, it is
said to have the south bearing, or a southing. If the line
lies to the east of north, it is also said to be east, and if to the
west, it is said to be west, and is so designated following the

Digitized by

Google

54 AGRICULTURAL ENGINEERING

number of degrees indicating the angle of the line with the
true north or south. Thus, a line in the right-hand quadrant
is northand so many degrees east; as, N. 4° 37 '. E. A line
whose direction lies in the left-hand quadrant is north, and
so many degrees west.

The Transit. It is not the piupose to include here

instructions in the use of the
transit. It is desirable, how-
ever, to explain in a brief way
the instnunent. The transit is
a universal siu^eying instru-
* ment, and it is arranged for
measuring horizontal and verti-
cal angles, for determining the
bearings by the magnetic needle,
for leveling, for measuring dis-
tances by means of an attach-
ment known as stadia wires,
and for determining bearings
from the sun when provided
with a suitable solar attach-

Flg. 40. A surveyor's transit. "^^^*> ^^ for many Other liuCS

of work.
PROBLEMS

The instructor should here arrange practice work in differential
and profile leveling, and surveying with the horizontal circle and com-
pass as far as the equipment provided will permit.

QUESTIONS

1. What is meant by differential leveling?

2. What is the piupose of profile leveling?

3. Describe the process of leveling.

4. How should level notes be recorded in the field book?

5. What is meant by a back sight? Height of instrument?
Fore sight?

Digitized by

Google

SURVEYING 55

6. Describe the process of leveling a field.

7. What is a contour map?

8. What is the use of the horizontal circle found on some levels?

9. Describe the compass.

10. What is meant by the "declination of the needle?"

11. What is the "bearing" of a line?

12. Describe the surveyor's transit, and for what may it be used?

REFERENCE TEXTS

The Theory and Practice of Surveying, J. B. Johnson.
A Manual of Field and Office Methods for the Use of Students in
Surveying, William D. Pence and Milo S. Ketchum.
Plane Surveying, John Clayton Tracy.

Digitized by

Google

PART TWO— DRAINAGE

CHAPTER IX
PRINCIPLES OF FARM DRAINAGE

Regulation of Soil Water. All vegetation is dependent
upon the water or moisture in the soil for life and growth.
Water dissolves the plant food in the soil and enables the
plant to absorb and circulate it throughout its struct\u*e.
Water also being transpired or given out by the plant, has a
cooling effect, which counteracts the heat of the binning
sun and prevents the plant from being withered or burned
up. The amount of water used by plants for theur most
satisfactory growth is called the diUy of water. Nature does
not always supply water to the soil in quantities conducive
to the most satisfactory growth of the plant. Often there is
too little water, and many times there is too much. Land
is drained for the piupose of relieving the soil of the surplus
water.

History of Drainage. The practice of land drainage
runs back to a very early date. Some of the most interest-
ing drainage projects of early times are the drainage of the
fens of England and of Haarlem Lake in Holland. Land
drainage by means of tile was introduced in Europe as early
as 1620, but it did not come into general use imtil about 1850.
Land drainage by tile was begun in the United States as
early as 1836, by John Johnson, a farmer of Geneva, New
York. These early drain tiles were made by hand. Tile-
making machines were introduced about 1848, and from this
time on, tile drainage increased rapidly.

Digitized by

Google

DRAINAGE 57

The area of the land m the United States which may be
improved by drainage is still large. It is estimated by Mr.
C. G. Elliott, formerly Chief of Drainage Investigation,
United States Department of Agriculture, that there are
yet 70,000,000 acres of land in the United States to be
reclaimed by drainage. In addition to this there are large
areas of land which could be made more productive and more
valuable by drainage.

Water in the Soil. The water in the soil may be classified
as capillary water and hydrostaJtic waier. Capillary water

Pig. 41. Land needing drainage. Typical conditions In northern Iowa
and southern Minnesota.

is that which covers the surface of the soil particles or grains
' as a film. It is the water in the soil which moves toward the
surface by capillarity as the water at the surface evaporates.
Hydrostatic water, or ground water, is that which fills the
open spaces between the soil particles and which obeys gravity
to the extent that it may be drawn off at the bottom

Digitized by

Google

58 AGRICULTURAL ENGINEERING

of a layer of soil if a suitable outlet be provided. When
water exists on soil particles in a very finely divided state it
is often called hygroscopic water. It is understood that
capillary water, as defined, would include this hygroscopic
water or moisture.

Lands Requiring Drainage. In general, land having an

Fig. 42. A good crop of corn on land which was a swamp the year before.

excess of water over that required to furnish the best con-
ditions for plant growth, needs underdrainage. The exact
conditions prevailing when an excess is present may be out-
lined as follows:

1. Comparatively flat land in which water collects in
basins or ponds from the higher surrounding land.

Digitized by

Google

DRAINAGE 69

2. Land kept continually wet by water appearing at the
surface, having seeped or passed underneath the surface
from land at a higher level. Such a condition is due to the
action of springs.

3. Flat land underlaid with an impervious stratum of
clay which prevents the water from sinking downward
through the soil. Often this condition is represented by an
old lake bottom.

4. Lands on which certain crops are grown, such as rice
fields or meadow lands, to which irrigation water may be
applied and removed at will.

5. Lands subject to overflow by rivers or tides.

Kinds of Soils. The kind of soil to be drained must by
all means be considered in connection with the planning of
farm drainage. The amount of capillary water that the
soil will hold varies largely with the fineness of the particles;
but a very fine soil will not allow water to pass through it
quickly, and for that reason is designated as a retentive soil.
There are other factors involved besides the fineness of the
soil particles; for example, the working or mixing of a finely
divided soil, such, as clay soil, while filled with water tends to
make it impervious, or water-tight.

An open soil is one through which the water will pass
quickly, and in which the pore space is not so finely divided
as in a retentive soil. The volume of the space between the
soil particles may be greater in the retentive soil than in the
open soil, as this space generally increases with the fineness of
the particles.

Kinds of Underdrainage. All soils need underdrainage,
that is, the hydrostatic or ground water should be drawn
oflf from the soil in some way. In most cases this under-
drainage is provided by nature, and the ground is said to have
natural underdrainage. The same may be true where the

Digitized by

Google

60 AGRICULTURAL ENGINEERING

surface of the ground is such as to give good surface drainage,
as where the land has a good slope. However, where natural
underdrainage is not provided, or where the surface is such
as not to provide surface drainage, artificial drainage should
be installed by means of tile drains or open ditches.

Underdrains. Artificial underdrainage is generally
accomplished by providing conduits, as open pipes, which
will provide a free , and as far as possible, an unobstructed

Fig. 43. An open drain.

passage for the flow of the water through the soil. To
secure the best results, these tile lines should have as much
fall or slope as is practical in order to give a high velocity of
flow to the water within them, and they should be as straight
as possible and free from sags and obstructions.

Open Drains. Open drains or ditches are simply free,
open channels for the flow of water, where large quantities
are to be cared for. They are used where a system of under-
drainage made of tile would not be practical. The advan-

Digitized by

Google

DRAINAGE 61

tages of closed or imderdrainage, where it may be used, are
obvious. It does not interfere with the cultivation of crops
or other operations conducted on the land.

Benefits of Drainage. Preparatory to the installation
of the farm drainage system, must come the consideration of
. the benefits to be derived and an estimate to determine the
advisability of the expenditure required, from the stand-
point of an investment. Certain drainage systems may be
justified as a protection to the health of the people of the
neighborhood. This value cannot be computed in dollars
and cents. Yet most farm drainage must be considered from
the business standpoint. In this connection full considera-
tion should be given to all of the benefits which may be
derived from the improvement of the land by drainage. In
general, it is to be expected that drainage will either reclaim
the land for farming purposes or make it more productive.
There are various ways in which land is made more produc-
tive by drainage.

Soil is Made Firm. When the level of the hydrostatic
water is lowered, the soil above becomes more firm. Thus the
wet marshy field in which a horse would mire may be made
so firm by drainage as to permit a team and load to pass over
it safely.

Soil is Made of Finer Texture. It has been proven con-
clusively that drainage causes the soil to become divided
into smaller particles, thus enabling it to hold a larger amount
of capillary water. The agents which bring about a disin-
tegration of the soil particles in underdrained soil are the
percolation, or passing of the water down through it, and the
action of air and frost.

The Growing Season Is Lengthened. Drainage lessens
the amount of water that evaporates from the surface and
the amount in the soil to be raised in temperature, permitting

Digitized by

Google

62 AGRICULTURAL ENGINEERING

the soil to warm up earlier in the spring, and to remain warm
later in the fall, thus indirectly increasing the length of the
growing season. The cooling effect of the evaporation of
water is known to all.

The Soil Temperature Is Raised. In a manner similar
to that just explained, the soil is maintained at a warmer
temperature throughout the growing season, assisting in the
rapid growth of plants.

Ventilation. Underdrainage causes the soil to be aerated ;
for as soon as the hydrostatic water is drawn away by the
drains, the space between the soil particles is filled with air.
This has a beneficial effect, since all plants require some air.

Prevents Surface Wash. When the hydrostatic water
of the soil is drawn away by imderdrainage, the soil is in a
condition to receive a very heavy rainfall before the water
will run off over the surface; or, in other words, imderdrainage
will enable the soil to provide a large reservoir for rain water.

Increases the Deptti of Soil. As the soil becomes warmer
and aerated, the roots strike deeper, thus increasing the
depth of the soil available for plant food.

Drouth. Strange as it may seem, well-drained soil
resists drouth better than wet. The greater fineness and
depth of the soil enable it to retain a larger amount of capil-
lary water, which is the water chiefly used by plants.

The Action of Frost Is Reduced. Soil which is filled with
hydrostatic water expands upon freezing and is said to
"heave." Although the action of frost may be beneficial,
as previously explained, heaving is very injurious to certain
crops which are planted in the fall. If the ground water of
the soil is drained out, this action is almost entirely over-
come.

Digitized by

Google

DRAINAGE 63

QUESTIONS

1. Why is water so necessary to plant life and growth?

2. What is meant by "duty of water?"

3. What is the purpose of land drainage?

4. When was tile drainage introduced in the United States, and by
whom?

5. How many acres may be reclaimed by drainage in the United
States?

6. Explain what is meant by capillary water. Hydrostatic water.

7. Give and explain five conditions of land needing drainage.

8. What is the difference between an open and a retentive soil?

9. How is artificial underdrainage secured?

10. When are open drains advisable?

11. Explain eight primary benefits of drainage.

Digitized by

Google

CHAPTER X
THE PRELIMINARY SURVEY

The Drainage Engineer. The services of a professional
drainage engineer are well worth their cost. The success of
any drainage system depends upon whether it is well planned
or not. If not correctly installed, the whole investment may
be worthless. Hence a small percentage of this investment
paid in fees to those who by training and experience know how
the work should be done is money well spent. It is not the
purpose of this text to detract from the work of the engineer,
but rather to lead to an appreciation of his work.

There is a difference between surveying and engineering.
Surveying includes only the taking and recording of such
field observations necessary for the designing of a drainage
system. The actual work involved in the designing and
execution may truly be called engineering. This latter work
involves much skill and experience.

The Need of a Preliminary Survey. The first step in
the drainage of any tract of land is the making of a prelimi-
nary survey or an investigation, which should be for the
purpose of obtaining a clear idea of the situation and a
general knowledge of the nature and amount of drainage
which will be required to accomplish the desired purpose.

The preliminary survey, then, is the basis upon which the
next step, involving the actual work of installing the drain-
age system, must depend. There are many things to be con-
sidered in the preliminary survey, such as information con-
cerning the character and value of the land before and after
improving. Careful investigations should be made to

Digitized by

Google

DRAIN AGS 65

determine if possible the fertility of the land after improving.
Then the drainage engineer should go over the tract in order
that he become thoroughly familiar with it before under-
taking any instrument work at all. If the tract is large and
if the ownership is divided, care should be taken that all
work from the outset shall conform to the law of the state in
which the tract is located.

The Extent of the Survey. In the drainage of all but the
smallest areas it is quite necessary to make the preliminary
survey before attempting in any way to decide upon the final
plan. The purpose of the preliminary survey is to obtain the
data &om which the final plans must be made. The data
secured should include the area of the drainage basin,
location of the water-shed, direction of the slopes and water
courses, and should indicate soil conditions and possible
outlets.

In securing this data it is necessary that the work be done
carefully. Mistakes are costly and can only be avoided by
careful work in securing correct information in the preUm-
inary survey. Careful work with crude instruments is often
more satisfactory than hasty work with expensive equip-
ment.

Investigation of the Subsoil. An investigation of the
character of the soil and subsoil should be made a part of the
preliminary survey, for on the data thus secured will depend,
to a large extent, the depth of and distance between tile
lines. This is quite important in land that is underlaid
with sand and gravel or with an impervious stratum of clay.
These investigations can best be made with the soil auger.
This tool can be made by welding a long handle to an ordinary
1)^ or 2-inch carpenter's auger. See Fig. 53.

Preliminary Instrument Work. An engineer's level
should be used in the preUminary survey to obtain elevations

3—

Digitized by

Google

66 AGRICULTURAL ENGINEERING

which will show definitely the lay of the land. It is not safe
for even the most experienced to estimate slopes by the
naked eye.

Map of the Preliminary Survey. A sketch or map
should be made indicaiting the location and elevation of the
low and wet areas in the land, and also the watershed. In
some cases where the land is quite flat it is desirable to take
levels at regular intervals over the entire tract, and, perhaps,
to prepare a contour map as explained in a previous chapter.
With this information it is possible to lay out the drainage
system, if conditions show that a practical system is possible.

It is desired to lay special emphasis upon the importance
of this preUminary survey. The quite common practice of
laying tile largely by guess, without a consideration of the
land area to be drained or the capacity of the tile, cannot be
too severely criticised. The large amount of insufficient
and unsatisfactory drainage to be foimd everywhere is silent
testimony to the statement that tile drainage must be done
carefully and intelligently.

QUESTIONS

1. What is the purpose of a preliminary survey?

2. Why should a drainage engineer be employed on important
work?

3. What is the difference between surveying and drainage engineer-
ing?

4. What should be included in the preliminary survey?

5. Why should the subsoil be investigated?

6. To what extent should an instrument be used in a preliminary
survey?

7. What should be included in the map of the preliminary survey?

Digitized by

Google

CHAPTER XI
LAYING OUT THE DRAINAGE SYSTEM

Definitions of Terms. Before beginning a discussion of
drainage systems it is well that the meaning of some of the
common terms used in connection therewith be explained.

The discharge end of the tile line or main is called the
outlet, and the upper or upstream end is called the head.
The term lateral is used for the single tile line with no
branches. The main is the line of large tile that carries the
discharge from a number of laterals. If the discharges from
several laterals are received into a larger tile line before it
reaches the main, the line which receives the discharge from
the laterals is spoken of as the submain. It is customary to
designate the laterals and submains by number and the
mains by letter.

Direction of Drains. As a rule, all drains should parallel
the slope of the surface. The surface of the ground water
is usually parallel to the surface of the ground and flows
down the slope. If tile be laid across the direction of the
slope, it will not receive any water from the ground below
the line, and in fact some water from above may flow past
the tile line. Rarely the lines may be laid across the slope
to intercept a seepage flow or to drain pockets in sub-surface
strata.

Depth of Tile Drains. Except in very retentive soil
through which the water does not percolate rapidly, the tile
should be placed at a good depth. It takes little time for
the water to pass straight down to a tile, but it takes more
time for it to flow horizontally through the soil. By

Digitized by

Google

68 AGRICULTURAL ENGINEERING

placing a tile deep, a large reservoir is provided for rainfall,
and the tile will have a longer time to carry the surplus away.
Distances between Drains. It is a practice in some
localities where an average soil exists, to consider that tile
will drain the water from the soil to a distance of one rod for
each foot in depth. As the ground water flows away through
the. tile lines after heavy rains, the level of the ground water
is first lowered directly over and near the tile, which causes
side flow of the water through the soil. If the soil is open or
sandy, this flow through the soil is rapid, and the level of the

Fiff. 44. Sketch showlner how the grround water is lowered and the capacity
of the soil as a reservoir increased by placiner the tile deep.

ground water between the tile lines will be lowered quickly,
and at no time will it be much higher than the level near the
tile Unes.

If the soil be retentive and resistant to the flow of the
water to the tile lines, the ground water may come very near
the surface at a rod or two from the tile. Thus the distance
between the lines depends not only upon the depth of the tile,
but also upon the character of the soil. In practice, lines
are placed 60, 75, 100, 150, and 200 feet apart, for average

Digitized by

Google

DRAINAGE

farm crops, depending upon the conditions and the thorough-
ness of drainage desired.

Systems of Tile Lines. There are several general systems
of arranging tile lines, each
of which is adapted to cer-
tain conditions. A descrip-
tion of the various systems
follows.

Nahjral System

Flgr. 45. The

natural system of
layiner out tile drains.

The natural system con-
sists in laying tile in natural
depressions, or it is an at-
tempt to drain the soil
needing drainage most.

The grouping system is
used where sloughs or basins
are encountered as well as
dry land Uttle in need of
dramage. The grouping system consists of mains running
into the sloughs with systems of drainage to thoroughly

cover the area of the soil
needing drainage.

The gridiron system is
used where complete drain-
age is desired, as on very flat
fields. The laterals are
placed parallel, and every
part of the entire area is
within a certain distance
At the
end of the parallel laterals,
mains or submains of larger tile are laid to collect the dis-
charge from as many as possible.

Pigr.

46. The grouping system of fro^ the tile Hue.
laying out tile drains.

Digitized by

Google

AGRICULTURAL ENGINEERING

Figf.

Gridiron System

47. The erridiron system of
layiner out tile drains.

laterals should be avoided
whenever possible, because
mains will drain the land for
some distance on each side,
and the part of the laterals
extending across the drained
area of the main is largely
useless as far as adding to
the drained area is con-
cerned.

Straight Tile Lines. Tile
lines should be as straight as
possible, and when curves
are reqiured they should not
be sharp. In addition to the
fact that the flow of water is
hindered to a greater extent
in tile lines with sharp turns ^

The single line system is
one in which the outlet for
tile lines is an open ditch.
Tile lines in this case are
independent of one another,
and each must have its own
outlet.

Large Drainage Systems.
In laying out a large drainage
system it may be necessary
to use several of the various
methods or systems of ar-
rangement. There are no
hard and fast rules for any
one system, though short

Singlc'Lmc System

FifiT. 48. The single-line system of
layiner out tile drains.

Digitized by

Google

DRAINAGE

than in straight tile lines, it is much easier to lay the tile in a
straight ditch than in a curved or crooked one. The system
should be so planned that all lands needing drainage should
be brought under the influence of the drains; or, in other
words, the system should insure thorough drainage.

Staking Out the Drains. After the general plan has been
decided upon, the next step is the staking out of the drains.
To do this, stations are located at distances of 50 feet apart
on the line of the proposed drain. Two stakes are required
at each station. One, the hub or grade stake, is driven into
the groimd, nearly flush
with the surface, about
one foot to the left of
where the center of the
ditch is to be located, as
one faces the outlet.
Levels are taken from the
top of these grade stakes
and the cut or depth of
ditch is figured down from Fig. 49.
them. These grade stakes
may be of any convenient material. Inch boards split into
widths of about 2 inches are very satisfactory. The length
should be sufficient to insure that the stake will be solid
in the groimd. Besides the grade stake, guide stakes of
lath or other light material are required. These are located
near the grade stakes to aid in finding them, and are
marked with niunbers to identify the stations.

All stakes should be left in place imtil the work is finished
and accepted. They should not be placed long before the
work is actually to begin, since they are quite Ukely to be
moved out of place.

'^1^'i^^^^jiOracfis Stake,
or Hub.

Grade stakes, oi
STuide stakes.

hubs, and

Digitized by

Google

72 AGRICULTURAL ENGINEERING

QUESTIONS

1. What is the discharge end of a tile line called? The upper end?

2. What is a lateral drain? A submain? A main?

3. How should tile drains be laid on slopes, and why should they
be so laid?

4. How deep should tile drains be placed?

5. What are some of the factors to be considered in determining
the distance between drains?

6. Explain the following systems of tile drains: The natural
system, the grouping system, the gridiron system, the single line S3rstem.

7. Why should short laterals be avoided?

8. Why is a straight tile line desired?

9. What two kinds of stakes are required in staking out a drainage
system?

10. Describe the location and purpose of each.

Digitized by

Google

CHAPTER XII
LEVELING AND GRADING TILE DRAINS

Taking Levels. After the drains have been staked, levels
should be taken with an instrument on the grade stake at
each station and recorded in the field book. This is the
process of leveling which has been mentioned in a previous
chapter. Notes for each line, be it main, submain, or lateral,
should be kept imder an appropriate title or head, and all the
levels should refer to
a common datum^ If
the instrument is pro-
vided with a compass,
the bearings of the
line should be record-
ed on the right hand
side of the note book
beside the level notes.
A good system of
notes is shown in the
specimen pages from
a field book found in
PartL

The Grade. The
amount of slope given ^^^ ,^ ^^^,^^ ,^^^,3 ,^ ^^^^^^ ^ ^^^^^^
to tile drains is called

the grade and is stated in several ways. The more common
way is to give the change in elevation of the drain for
every himdred feet of length. It is also stated as the
percentage the change of elevation is of the length. Thus

Digitized by

Google

74 AGRICULTURAL ENGINEERING

a grade of .02 foot per hundred feet is equal to .02 per cent,
etc. Again, the grade may be stated in inches per rod, as,
J^ inch per rod or 1 inch per rod. It is customary to refer
to the grade as the "fall." Then a grade of .1 foot per 100
feet is called a "fall" of .1 foot per himdred feet, and a grade
of 1 inch to the rod has a "fall" of 1 inch to the rod. The
line of the bottom of the finished ditch, or the line on which
the tile is laid, is called the grade line.

Establishing Grade Lines. After the elevations of the

grade stakes have been obtained, it now falls to the lot of the

^^ =

57 I

56
55
54

53^

'"%

5/ =

0/a04-5C7S9t0n

Prof He of Main.

Fig. 51. A profile of a tile drain.

drainage engineer to establish the grade for the tile lines.
There are two methods in common use for doing this, and
they will be explained in turn.

Grade Profile. One simple and also very satisfactory
way of establishing the grade for the tile drain is to plot
the system on profile paper, using a vertical scale to show the
elevations of the various stations, and a horizontal scale,
the distance between stations. The vertical scale should
show differences of at least 1-10 of a foot in elevation. It

Digitized by

Google

DRAINAGE 76

is now an easy matter to draw trial lines upon this profile,
locating the grade of the tile drain. The determination of
*he grade line usually resolves itself into the problem of
locating the outlet as low as possible, with the head deep
enough to secure good drainage and at the same time high
enough to provide sufficient fall for the line.

Sometimes a thread is stretched across the profile as an
aid in deciding the proper location. After the grade has
been properly located, the elevation of the grade line at the
various stations may be read from the scale of the profile.

Second Method. If the elevation of the grade Une at the
various stations be subtracted from the elevation of the sta-
tion, the cut, which is the depth of the ditch at that point,
will be obtained. It is convenient to adjust the grade to
even hundredths of a foot per 100 feet, as, .02 or .25 foot per
100 feet. Two additional columns should now be utilized
in the field book. One should be marked G. L., which is to
contain the elevations of the grade Une at the various sta-
tions; the other is marked "cuts," and contains the depth
of the ditch below the top of the grade stakes at the various
stations. It is possible to locate the grade line and deter-
mine all cuts at various stations along the line, without the
extra work in connection with the drawing of the profile,
but the profile is regarded more desirable.

Unifonn Grade Desirable. A uniform grade should be
used throughout the tile lines as far as possible, though it may
not be economical in all cases. For example, if the tile line
is to run through a ridge to an outlet, the grade will likely be
established by placing the tile at the minimum depth at the
head end of the tile drain to reduce the cut through the ridge
as much as possible and still secure a practical grade for the
tile line from the head end through the ridge. After passing
through the ridge the grade may be increased. It is always

Digitized by

Google

76 AGRICULTURAL ENGINEERING

more desirable to have an increase than a decrease in the
grade. Where the grade is reduced there is a reduction
in the velocity of flow at that point, which permits the silt
in the water to settle in the tile.

Joining Laterals to Mains. When laterals or submains
are joined to another drain, it is advisable to have a slight
fall, or drop, as it is called, into the main at the end of the
drain. The amount of drop should be proportioned to the
size of the tile into which the drain discharges. Thus for
the 6-inch main the drop from the lateral should be 0.2 foot;
for an 8-inch, 0.3 foot; for a 10-inch, 0.4 foot; and for a
12-inch, .5 or J^ foot. To compute the elevation of the start-
ing point for each drain when a drop is to be provided, the
amount of the drop should be added to the grade elevation
of the main at the junction.

Construction Figures. It is customary for the engineers
having the work in charge to indicate upon the guide stakes
the cut at the various stations. For convenience of those
digging ditches, the engineer often changes the decimal of the
foot to inches. It is also customary to furnish to the tile
ditcher a tabulated list of the cuts at the various stations.
Sometimes this is furnished and the marks on the guide
stakes are omitted.

The Final Map. After the drainage system has been
located and all the field observations made, all data should
be reduced to a permanent map. This map should show the
location of each drain, its length, head, outlet or junction
with another line; the number and size of tile required;
location of all surface inlets, silt basins, etc. It is also well
to record the grade of the drain from point to point and the
surface elevations and cuts at representative places. No
reputable engineer would think of undertaking the design of

Digitized by

Google

DRAINAGE

a drwiage system without providing the owner of the tract
drained with such a map.

-x^

Fig, 62. A drainage map.

QUESTIONS

1. What should be recorded in the field book when taking levels
for a tile drain?

2. What is meant by the "grade'' or ''fall/' and in what three
ways may it be designated?

3. What is meant by the grade line?

4. Explain two methods of establishing the grade line.

5. Why is a uniform grade desirable?

6. Explain how laterals should be joined to mains or submains.

7. What construction figures should be placed on the guide stake?

8. Describe the construction of the final map.

Digitized by

Google

CHAPTER XIII
CAPACITY OF TILE DRAINS

Cause of Flow in Tile Drains. If water be poured into an
inclined pipe or other conduit, it will flow toward the lower
end. This flow is produced by the action of gravity. The
effect of gravity may be observed in the phenomena of f alUng
bodies, and the law for the velocity of falling bodies is usual-
ly expressed by the formula:

V - |/ 2 gh

where V is equal to the velocity in feet per second, g the accelerating
force of gravity, and h the distance through which the body falls.

Thus a freely falling body starting from rest will have
a velocity of 32.2 feet per second at the end of the first
second. At the end of the second second the velocity will
have increased to 64.4 feet per second, and there will be an
increase in velocity each second, or it will continue to accele-
rate thereafter. It is this same force which causes the flow
of water in tile drains, and there can be no other agent to
produce the flow. In the tile drains, however, there are
many influences to interfere with the acceleration of velocity,
which tend to make the velocity imiform.

Velocity Formulas for Flow of Water. There have been
many attempts to incorporate into a formula the various
factors which produce and retard the flow in tile drains, and
many such formulas have been proposed. The extent to
which these forces retard the flow of water in pipes cannot be
determined accurately. Some of these forces are the resist-

Digitized by

Google

DIIAINAGE 79

ance to the entrance of water into the pipe, the resistance of
the walls of the pipe to the flow of the water, which varies
largely with the roughness of the inside of the pipe, the
obstructions at joints and bends, and the amount of sedi-
ment deposited, etc.

Poncetet's Formula. One of the more generally used
formulas which have been proposed for the flow of water in
tile drains, is Poncelet's formula. The usual way of stating
this formula is as follows:

For mean velocity:

V'^s^/rr"

54d
In which

d = diameter of tUe in feet.

h = head, or difference in elevation between outlet and upper end,

in feet.
I » length of drain in feet.

Modification of Formula. Under varying conditions
which are encountered, certain modifications of the formula
will be found necessary. Thus in open soil where the water
is free to enter the tile line, it is recommended by Mr. C. G.
Elliott, formerly Chief of the Drainage Investigations, of the
United States Department of Agriculture, that }4 of the
depth of the soil over the drain at its head be added to the
quantity dA, making the formula read :

= ^«i/

dh + J^k

I + 54d
In which

k = the depth of the soil over the drain at its head.

Mr. Elliott also recommends that an increase in the
head be made in the case of mains which have a com-
paratively large number of laterals, on account of the drop
of these laterals into the main. This drop in the submains

Digitized by

Google

80 AGRICULTURAL ENGINEERING

tends to increase the velocity of the flow in the mains.
These modifications are not governed by any law and they
require judgment for their use.

Run-off from Underdrained Land. In addition to know-
ing the capacity of a tile drain, the engineer must know
something about the amount of water which must be taken
care of from the given area. This is usually spoken of as the
"run-off, "and is measured by the depthof the water received
if spread over the entire area. Thus a run-off of }/^ inch for
an acre is the water received from that area in 24 hours, and
is sufficient to cover the acre to the depth of ^ inch. Many
experiments have been conducted to determine the run-off
from given areas. Sometimes this quantity is spoken of as
the "Standard Drainage Coefficient," or "Standard."
The common standard used for small areas in which tile
drainage is practiced is the 3^-inch standard. For larger
areas the standard is larger. In this connection, due con-
sideration should be made for surface water which may flow
to the underdrained land from adjoining land. This may
necessitate the doubling of the capacity of the tile otherwise
required.

Application of Formula. In order to use the formula for

the capacity of the drain tile, it is necessary to know the

quantity of water discharged per second. This is a simple

matter, as the quantity of water is equal to the area of the

dram, times the velocity. Thus,

Q = ot^

where Q is equal to the quantity of water discharged per second, a is
equal to the area in square feet of the cross section of tile, and v
equals the velocity in feet per second.

In addition to this it is necessary to know the number of
cubic feet per second that is equivalent to the standard used.

Digitized by

Google

DRAINAGE

This may be computed by dividing the total quantity of
water on an acre, for a certain standard or depth, by the
number of seconds in 24 hours. For convenience, however,
the following table is included.

Discharge per second per acre for different depths of runroff.

Common fraction
1

15-16

7-8

13-16

3-4

11-16

9-16

1-2

7-16

3-8

5-16

1-4

3-16

1-8

1-16

Depth in inches.

Cu. ft. per sec.

Decimal

per acre

1.000

.0420

.938

.0394

.875

.0367

.812

.0341

.750

.0315

.688

.0289

.625

.0262

.562

.0230

.500

.0210

.438

.0184

.375

.0157

.312

.0131

.250

.0105

.188

.0079

.125

.0052

.062

.0026

In applying the formula it is customary to assmne a cer-
tain size of tile and then make the computation to determine
whether or not the tile will be sufficient. If too small,
another trial may be made with a larger tile. As an illus-
tration, suppose that the size of tile necessary to drain 80
acres is required, when the line is 1000 feet long and is laid
to a grade of 4-10 foot per 100 feet, assuming the drainage
standard or coefficient of ^i inch.

Referring to the formula.

54d

Digitized by

Google

82 AGRICULTURAL ENGINEERING

Assume that an 8-inch tile will be required, then:
d = diameter of tUe, = 8 inches or % foot.
h = total head or fall = .4 X = 4 ft.

I = 1000 feet.

54d = 54 X % = 36.

o = area of cross section of tile = Ji X 3.1416 X (%)' =.349
square feet.

V= 48n/ JiA± = 48t/IZI =48l/~5^^
"^ 1000 + 36 ^ 3108 ^

= 2.40 feet per second.
Q = cubic feet discharged per second, and equals the velocity X
area of cross section of tile = 2.4 X 349 = .8376.

Referring to the preceding table for the discharge per
second per acre for the J^-inch standard, we find .0105.
Then the number of acres drained is

.8376 ^^^ . „ ^^

A = = 79.6, or practically 80.

.0105

If the answer representing the discharge per second pro-
cured in this manner should be too great or too small, the
calculation would be made for smaller or larger sizes of tile,
as the case may be, and the most practical tile to use chosen.

To facilitate the use of the formula, a table may be made
up from it, showing the number of acres which may be drained
with various sizes of tile laid to various grades. The follow-
ing is such a table, from Bulletin 68 of the Iowa experiment
station.

Digitized by

Google

DRAINAGE

:5§

-I

i-H i-H 00 i-H C^

C0'^»Ot>.00

,-1 ,-1 ,-1 ^ rH ,-H i-H i-H C^ C^

^ ^ CO »C> 05

^c^Q'^gj

1-H i-H 1-J 1— I 1— I i-H 1— I C< C<

jO-Tt^COOOOi QOOOOOi-iC

^ -^ CO

ocor^iow

(NC^CO'^iO

<ot^aoo>o>

OiCOCOOCO N.
O ^ ^ '^ CO Oi'

C^OOOOQO
OOOrt<i-icO

»o»ocot^t^

ooooa>^(M lo

O^CO(NtJi

ocooococo

c^t^^iooo <Niooo(Nco c^^:

OSiOOiWCO

ior*oco»o

00 CO CO CO t^

OO^TjiCOOO

rococoes »o coc

OW'^^00 05C. _
COC0C0Tt<Tj< »ocot>.

s§

t^ Oi 05 »0 l^

CO'^COOOOS

OiOO"^OiC^
i-iCO»OCO«

lOt^oor^Oi t^t^co
OiOi-^cOO l>CO0p

00005CO

CO 05 M* 00

CO 05 ^ 00 O
CO CO ^ ^ *o

»O»OCOI>00 oc^cocoos

«OI>050 C^TjicOt^Oi

WC^C^<NCO CQTjiiOCOl^

Tj^Tt^io cor^xoso ooi-Hcoio oc^^o^o

^ ^pHfH^^ ^wwcoco

COC^COC^ coco CO CO

^op^coop j^ ^op ^^

1-HCOCOOiCO dscO coco OiCO

coco CO

^^opop^

ioiot>.i>co

i^^pH i-Hi-HC^CO"^ »OlN.05Tj<0i

8§22S ^iggg S88S8 888S8

doddd odddd dd^^(N' c6'^»oi>d

Digitized by

Google

AGRICULTURAL ENGINEERING

Size of Laterals. The size of laterals may be fixed as
soon as the available fall is obtained by the taking of levels.
In general, it is not regarded good practice to use small tile in
laterals. The use of 3-inch tile has been quite generally dis-
continued in favor of 4-inch. The larger tile is less likely to
be influenced by imperfect construction, and the difference
in cost is small. There is a minimum grade for tile lines
less than which it is not practical to lay tile. If the soil is
free from sand or other sediment-forming elements, the grade
may be quite flat; however, if the soil is sandy a considerable
slope should be provided.

On account of the resistance to flow in small tile, it is not
best to make lines of small tile longer than a certain length.
The following table gives the minimum grade and maximum
length of tile lines which are practical with various sizes of
tile.

Table shotoing minimum grade and length for tilee of various sizes. * .

Size of tile in inches

Minimum grade in
feet per 100 feet

Limit of length in
feet

.10
.06
.06
.06
.06
.05
.05
.05
.04
.04

800

1600

2000

2500

2800

3000

3500

4000

4500

5000

*From Elliott's "Engineering for Land Drainage.'

PROBLEMS FOR PRACTICE IN THE USE OF THE FORMULA

1. Find the number of acres that may be properly drained by a
6-inch tile line 20 rods long, if laid with a grade of 2-10 of a foot per 100
feet.

Digitized by

Google

DRAINAGE 85

2. What size tile should be used to drain properly a 40-acre tract,
if the line is 1200 feet long and laid with a grade of 3-10 of a foot per
100 feet?

(The following problems are taken from Bulletin 78 of the Iowa
experiment station, involving the use of the table.)

3. What size of tile laid to a 0.1 per cent grade will carry the under-
drainage of 160 acres of flat land? Ans., 15 inches.

4. What size of tile laid to a 0.2 per cent grade will carry the under-
drainage of 240 acres, ^ rolling? Ans., 80 acres flat land plus }4 of
160 acres roUing gives 133}^ acres, requiring a 12-inch tile.

5. What size of tile laid to 0.3 per cent grade will be required to
remove both ground and surface water from a pond whose watershed
includes 40 acres? Ans., 10-in. (Note. — Double or triple the area for
both ground and surface water.)

QUESTIONS

1. What causes the flow of water in tUe drains?

2. What are some of the factors which influence the velocity of the
flow of water in tile drains?

3. Give and explain Poncelet's formula.

4. What modifications of the formula may be made, and why?

5. What is meant by a standard drainage coefficient, or standard?

6. How is Poncelet's formula used?

7. How may the capacity or discharge of a tile be obtained from
the velocity of flow?

8. Why is a table convenient in determining the size of tile?

9. What is meant by maximum length of tile lines?

Digitized by

Google

CHAPTER XIV
LAND DRAINAGE

Digging the Tile Ditch. After the survey and the depths
of the grade lines at all stations have been marked plainly
upon the guide stakes, it then becomes the duty of the tiler
to dig the ditch, or trench, accurately to grade, and to place
the tile closely and firmly upon the bottom.

Fig. 53. Hand tools used in diggring tile ditches. Nos. 1
and 2 are square-end tiling spades, 3 and 4 are open or skele-
ton tile spades. 5 is a tile scoop or crumber. € is a round-
point shovel, 7 is a tile hook, and 8 a soil auger.

Hand Digging. Tile ditches are quite generally dug by
hand, and under certain conditions it is the only practical
method. The ditch is usually dug so that the center of the

Digitized by

Google

DRAINAGE 87

top of the ditch will be about one foot from the line of grade
stakes. A straight ditch indicates good workmanship. To
secure straightness, a small rope may be stretched along the
line of the ditch. Curves may be laid out by using the rope
as a radius and marking numerous points along the line of
curve by short stakes.

The tools required for digging ditches by hand are not
nmnerous. A ditching spade with a 16- to 20-inch blade is
most generally used. In muck soils^ an open three-tanged
spade will be more satisfactory. To clean out the loose soil
from the bottom of the ditch, a long-handled round-nosed
shovel is the most efficient tool. To take out the last bit of
soil and to shave the bottom of the ditch down to an even
grade to receive the tile, a tiler's scoop, or crumber, is neces-
sary.

Ditching Machines. Owing to the large amount of labor
involved in digging tile ditches by hand, attempts have been
made for years to design a machine which would do the work
successfully. At the present time there are some machines

Fig. 54. A tile ditching machine at work.

Digitized by

Google

88 AGRICULTURAL ENGINEERING

that do very creditable and economical work. Tile ditching
machines have either a power-driven wheel or an endless
chain, on which knives and buckets are attached for loosening
the soil and carrying it above the surface where it may be
deposited on a conveyor and carried to one side of the ditch.
The machine must be so constructed that the cutting
mechanism can be easily raised or lowered and equipped
with sights or gauges which indicate clearly the depth the
machine is digging. Steam and gasoline engines are used

Fig. 55. A large tile ditching machine at work.

*o furnish the power. Traction gearing drives the ^ whole
machine forward at the proper speed, which, in favorable
soil, may be as much as 175 feet per hour when digging four
feet deep or less.

The great difficulty in the past has been to design a
machine which would dig a ditch to grade in soft soil having
but little supporting power. This has been overcome to a
great extent by providing caterpillar traction wheels or

Digitized by

Google

DRAINAGE 89

treads which provide a large area of supporting surface.
These machines can be used to the best advantage on long
lines of tile and where the soil is reasonably dry and free
from boulders. In no case should a machine be used which
does not permit of an inspection of the grade and of the tile
as it is laid.

The Guess System of Laying Tile. At the present time
there is very httle tile placed in the ground on grade lines
made simply by guess. The majority of such systems are
failures, and mistakes have been so evident where this
method was practiced that it is uncommon now to see a
system installed without a survey.

The Water-Level Method. But little better than the
guess method of installing drainage systems, is the water-
level method, which is used to some extent today and is
responsible for a large number of failures. This method of
laying tile is used where there is some water in the ditch.
Where the fall is shght, water can not be depended upon to
give a proper grade. The ditch is sure to be dug below the
grade at certain places, giving a back fall. After the ditch
has been dug too deep, there is little chance of correcting the
mistake by filling in. The water-level method is so inaccu-
rate that, even where
the fall is great and
there is little danger
of creating back fall,
the grade line will be
so irr^ular that the
efficiency of the tile
will be much reduced.

Method of Grad-
ing Ditches. Two
general methods of ^*^- "' ''''' ""'diJJhe^.r^ "' ^"^"' '"'

Digitized by

Google

90 AGRICULTURAL ENGINEERING

grading ditches are in vogue. One is to stretch a cord or
line above the surface parallel to the grade line, using a
measuring stick to locate the grade. This is generally known
as the ''line and gauge method." The other, the "target
method/' consists in locating a line of sights or targets above
the ditch, parallel to the required bottom, and the depths at

all points are gauged by
sighting over these sights
and using a measuring
stick to determine the
proper depth.

When the line is used
it must first be decided
how far above the bottom
of the ditch to place it,
and a measuring rod of
this length provided.
Five or seven feet are
convenient distances for
the usual depth of dig-
ging. The line may be
stretched directly over the
ditch or to one side. The
first instance requires that
a yoke be constructed
over the ditch, while the

Fig. 57. The target method of grading i . . . ,

tile ditches. latter reqmres only a

single standard or stake.
Some tilers object to the line stretched over the ditch,
as it is more or less in the way, but there is no doubt that
more accurate measurements can be made when the line is
so placed. If the line be stretched at one side of the ditch,
a measuring stick with a bracket must be used. To obtain

Digitized by

Google

DRAINAGE 91

greater accuracy, a level-tube is sometimes placed on the
horizontal arm of the bracket. The height of the line above
the grade stake at each station is obtained by subtracting
the cut from the distance the line is placed above the grade
line. Thus, if 7 feet be selected as the length of the measur-
ing stick, and the cut at a certain station be 3 feet 5 inches,
then, the line should be placed 7 feet less 3 feet 5 inches,
or 3 feet 7 inches above it. If this operation be performed
at all stations, it will be seen that the line will be parallel
to the bottom of the ditch and 7 feet above it. A j&shline or
a fine wire makes an excellent line to use for this purpose,
as it may be stretched very tight, overcoming the sag to a
large extent. Some experienced tilers prefer the "target
method," as it is more convenient. It is, however, more pro-
ductive of errors.

Selecting Tile. Great care must be used in selecting
drain tile. Farm drainage is too expensive for one to take
serious risks with tile of questionable durability. At the
present time there is much discussion in regard to the rela-
tive merits of clay and cement tile. Attention has been
called repeatedly to instances where both kinds have failed.
Clay tile has the advantage in that it has been in use a much
longer time than cement tile, and a good clay tile is as per-
manent as any material that can be secured. Careful speci-
fications for tile and methods for testing the same have not
as yet been prepared or devised.

Clay tile should be well burned and of uniform shape and
color. They should be straight, with square ends, and when
two are held in the hands and struck together they should
^ve a good sharp ring. Large lumps of chalk or lime in the
clay must be guarded against. Inferior tile are those of light
color,, porous and laminated. These are quite sure to become
disintegrated when placed in the soil.

Digitized by

Google

92 AGRICULTURAL ENGINEERING

Cement tile are very satisfactory when properly made
and are of recognized quality. No attempt should be made
to make the tile porous, but as dense a mixture of cement as
it is possible to secure should be used. Where good coarse
sand is used, a mixture of 1 part cement to 23^ parts of sand
has been used by the best manufacturers. A mixture con-
taining less cement will no doubt make good tile. Large
cement tile should be reinforced with steel.

Fig. 58. Drain tile. Those at the left are of cement and those at the
right are clay.

In installing a drainage system, a careful inspection of the
tile should be made. All inferior tile which are soft, porous,
cracked, or overbumed until of reduced size, should be
discarded.

Laying Tile. Great care should be taken in laying the
tile. Small tile should be laid with the tile hook (See Fig.
59), but there is little doubt that the tile is laid more accu-
rately when laid by hand. Each length should be turned as
it is laid to secure the best fit. When a tile hook is used on
tile which are slightly curved, the bend of the tile is quite sure
to be up, leaving a larger crack at the top of the tile rather

Digitized by

Google

DRAINAGE 9a

than at the bottom, which is undesirable. Tile should be
fitted together so that
there are no cracks over
J^inch wide. Small holes
at the joints may be cov-
ered by broken pieces of
tile.

In digging the ditch
and laying the tile, the
work should always begin
at the outlet. The tile
should be laid as fast as
the ditch is dug, to pre-
vent the destruction of
the ditch by rain. This
would happen if the water
should be allowed to flow
down the unprotected
ditch. In most soils, the
open ditches are quite

likely to cave in if left Fig. 59. Laying tlle with the tlle hook.

open during rain storms.

Laterals should be joined to a main by '* Y" connections

furnished by the tile manufacturers. The cheapness of these

connections does not justify
the work of cutting tile to
form a connection. Laterals
should enter the main at as
sharp an angle as convenient.
When the connection is made

JlWot t^^iM^TU^^o at right angles, the flow of

main,. From Ohio Exten. Bui. 47. ^^ ^^^^ ^^ ^j^^ ktcrals

has a tendency to check the flow of the water in the maina.

Digitized by

Google

94 AGRICULTURAL ENGINEERING

In laying through quicksand, time should be given for
the water to drain out and allow the sand to become as firm
as possible. This is rather a slow process at times, but it is
the only method to follow in watery quicksand. To prevent
the sand from flowing into the open end of the tile, a screen
of hay or grass may be used. If there are bad pockets, it
may be necessary to lay the tile upon boards to keep them
to grade.

Inspection. Before the tile are covered the work should
be thoroughly inspected to see that the tile are laid to grade,
and that the openings between the tile are not too large. In
iijspecting the grade, the level may be set over the Une of tile
and the line of sight set to the same slope as the grade line.
The reading of the rod held upon the top of the tile should be
the same at all points, so long as the slope of the grade Une
does not change. After inspection, the tile should be
"blinded in" by cutting enough dirt from the side of the
ditch to cover it to the depth of two or three inches. This
earth from the side of the ditch is more porous than that from
the surface, and permits the water to enter the tile more
readily. The shoveling and spading of the soil have a ten-
dency to puddle it and make it water-tight. After blinding,
the ditch inay be filled.

QUESTIONS

1. What is the work of the tiler?

2. Explain in a general way the digging of tile ditches by hand.

3. Name and describe the tools used in tile ditching.

4. Where may tile ditching machines be used to advantage?

5. How much ditch may be dug with a machine in an hour under
favorable conditions?

6. Why should not tUe be laid by guess?

7. Explain the "water level" method of installing drains.

8. Describe the line method of digging ditches to grade.

Digitized by

Google

DRAINAGE 95

9. What relation does the line of targets or sights in the target
method of digging ditches to grade, bear to the grade line?

10. What points should be observed in selecting drain tile?

11. Explain in detail how the targets are located. The line.

12. Describe the use of the tile hook.

13. How should tile be fitted?

14. How may tile be laid through quicksand?

15. What is meant by "blinding" the tile?

16. Why should tile hnes be inspected?

17. Describe the work of inspection of tile drains.

Digitized by

Google

CHAPTER XV
CONSTRUCTION OF TILE DRAINS

Ftttinc ^7 Hand. After the tile are laid and blinded in,
4i» tttt^ hand labor as possible should be used in filling the
\)Utli«s« The usual price for the work of filling ditches by
Ivfont b ten cents per rod, while the same work will cost one
H> two cents per rod where horses and implements are used.
{)t wurse there are places near and under fences or embank-
iut^uti» where the ditches must be filled by hand.

Pig. 61. Pilling the ditch with a plow.

Filling with the Plow. One of the most convenient and
satisfactory methods of filling a tile ditch is to plow it full.
To do this successfully, an ordinary stirring plow may be
used, one horse being hitched to each end of a long double-

Digitized by

Google

DRAINAGE 97

tree which will permit one horse to walk on each side of the
ditch. The soil and waste banks are plowed toward and
into the ditch until it is entirely filled. It is best that one
man drive the team while another hold the plow. Three
horses may be used upon a twelve-foot evener, two horses
hitched to one end and one to the other. In this case the
plow is attached four feet from the end to which the team is
hitched. The plow is not well adapted for filling ditches dug
in meadow land.

Filling with a V Drag. A V drag is a useful and quick
means of filling ditches. The wings of the drag should be
wide enough in front to reach from the outside of one bank
of excavated earth to the outside of the other, and should be
brought to within a few feet of each other at the rear.

Filling with Road Machines. A scraping road grader may
also be used to fill tile ditches. The blade may be set at such
an angle that the waste bank is scraped over into the ditch,
like the road drag, the road machine will do good work if the
groimd is not too wet.

Another common method is to fill the ditch with a slip

Fig. 62. Filling the ditch with a road grader.

Digitized by

Google

98 AGRICULTURAL ENGINEERING

scraper or other form of handled scraper. A team is hitched
to the scraper by a chain so as to pull directly across the
ditch. The scraper is placed behind the waste bank, and the
team stepping ahead pulls a scraper load of earth into the
ditch. The team is then backed and the scraper pulled back
by hand. The latter operation furnishes the greatest objec-
tion to this system, for it is very heavy work.

Outlet Protection. All tile outlets should be protected
in such a manner that the earth will not be washed away

from the end tile
and cause them to
be displaced. The
cheapest form of
outlet is made by
preparing a wooden
box into which the
last few lengths of
tile may be placed.
This is not a very
satisfactory form of
protection. The bet-
ter plan is to build a

Pig. 63. A good outlet protection for a tile bulkhead of maSOnrV
drain. It Is desirable, however, that grating '^

or bars be placed across the outlet to keep out and an aprOU UPOU
small animals. ^ *^

which the water
may spill without washing away the soil. The latter
may not be needed, or a few stones will generally suffice.
Concrete makes a splendid bulkhead. A six- to ten-inch
wall where only two or four feet of earth is to be held
back will be found sufficient. This wall should extend well
below the tile to prevent undermining. The last few tile
should be glazed sewer tile, as they will resist freezing and
thawing better than common drain tile. Iron rods or netting

Digitized by

Google

DRAINAGE 99

should be placed across the outlet to prevent the entrance of
small animals which might, by dying in the tile, become an
obstruction.

Catch Basins, or Surface Inlets. Where there is sure to
be considerable surface flow, it is best that this be taken into
the tile as soon as possible. The catch basin is simply a
grated inlet leading directly to the tile. The basin is usually
built deeper than the tile to allow dirt, which might be
washed in, to settle and not be carried into the tile with the
water. This sediment should be cleaned out from time to
time.

A concrete box, 33^ feet across and with 4-inch walls,
makes a very satisfactory
catch basin. The box
should extend 2 feet below
the line of tile and should
have a removable cover.
Large sewer pipes with
side connections can be
used conveniently for this
purpose.

Silt Basins. Silt basins
have been recommended

for tile lines where the Fig. 64. a siit basin.

grade is reduced, and are

designed to provide a receptacle to catch the silt that is
likely to settle at that point. They are constructed with
removable covers through which the sediment may be re-
moved from time to time. There is Uttle doubt that these
devices are very harmful in checking the flow of water in the
tile, and it has been the experience of the author that these
basins are never given attention when they require it.

Digitized by

Google

100 AGRICULTURAL ENGINEERING

Trouble with Roots of Trees. Tile drains laid near
aquatic, or water-loving, trees, are sometimes partially, if
not entirely, obstructed by roots of these trees. The willow
and water elm are among those that give the most trouble in
this respect. Fruit trees give very Uttle trouble, and drains
may be laid in orchards with impunity.

If a drain must pass within 30 or 40 feet of any of the
trees that are aquatic by nature, the trees should be cut down

Fig. 6B. A tile drain which became completely obstructed by roots
from a willow tree.

and killed, or sewer pipes with cemented joints should be
used near the trees, which will prevent the roots from getting
into the drains.

Drainage Wells, or Sinks. Wells are occasionally used
as outlets for tile drains. It is known that about as much
water may be discharged into a well as may be pumped from
it. An investigation of the success of wells as drainage out-

Digitized by

Google

DRAINAGE

101

lets in Iowa reveals that in certain localities wells are emi-
nently successful; in others, they are failures after a very
short time. The successful wells seem to be those that
penetrate crevices in the rock stratum below the surface.
These wells seem less likely to become clogged with the fine
silt carried into the well by drainage waters. It is under-
stood that these wells are to be used for no other purpose
than as drainage outlets.

Cost of Drain Tile. To those unfamiliar with tile drain-
age, it is thought that the following schedule of tile prices
at the factory will be useful. It is to be remembered that
prices must necessarily vary with factories, and freight in
many cases is a considerable item.

Cost of drain tile at the factory.

Size of tile in inches

Weight. Lbs.

Cost per 1000

7
9

17
26
35

$ 16

100

Schedule of Prices for Digging Ditches. The follow-
ing schedule prices have been in quite general use through-
out Iowa during the year 1911.

Co8t of digging tile ditches.

Sise of tile
in inches

Price per rd.

3 ft. deep or

less

Extra per rd.

for eacn inch

of depth over

3 ft.

Extra per rd.

for eacn inch

of depth over

6 ft.

4, 5. and 6

$.44
.50
.62H
.75

$.01}i
•OIJ^
.02
.03

$.03

7 and 8

.03 Ji
.04

9 and 10

.05

Digitized by

Google

102 AGRICULTURAL ENGINEERING

QUESTIONS

1. Why is it advisable to use little hand labor in filling the ditches?

2. How may the plow be used in filling ditches?

3. Describe the use of the V drag and road grader in filling ditches.

4. Why should the outlet of a tile drain be protected?

5. Describe the construction of an outlet protection.

6. What is the purpose of a catch basin?

7. Describe the construction of a catch basin.

8. Where is a silt basin used and what is its purpose?

9. How may tile drains be protected from the roots of trees?

10. To what extent may a well be used as an outlet for tile drains?

11. Compare the prices of drain tile furnished in the text with
those of your town or city.

12. What are the usual prices charged for tile ditching?

Digitized by

Google

CHAPTER XVI
OPEN DITCHES

Drainage of Large Areas. Where large areas are to be
drained, it may not be practical to install tile of sufficient
size to care for the drainage water or rtin-ofif. Thus in the
large drainage systems it is to be expected that open ditches,
as distinguished from covered or tile lines, will be used to
supplement the tile.

Construction of Open Ditches. In the construction of
open ditches, not only
the size must be con-
sidered, but also the
form of the ditch.
The size of the ditch
will depend upon the
capacity of ditches
dug to various grades
and upon the area
and character of the
catchment basin. The Fig. es.
capacity of open ditch-
es will be discussed later. Care should be used in construct-
ing the banks of the ditch so that the ditch will remtdn
open and not become filled by the caving of the banks.

In certain soils a slope of 1 foot horizontal to 1 foot ver-
tical for the sides of the ditch may be maintained; and in
other cases, as in the case of loam soil, the slope must be IJ^
to 1, or even less. In dig^ng a ditch it is often not possible
to secure the desired slope in the beginning, but the ditch

103

A floating dredge for digging open
ditches.

Digitized by

Google

104 AGRICULTURAL ENGINEERING

is made deep enough so that as it caves in it will still be of
suflScient size. The heap of excavated earth from a ditch is
called the waste bank. The space between the waste bank
and the edge of the ditch is called the berm. Waste banks
present an ugly appearance and are an objectionable feature
of open ditches, unless the earth is used to fill in low places.

Cost of Open Ditches. Small open ditches are made
with the plow or scraper. These are usually undesirable, as
they do not furnish a good outlet for the ground water.
Large open ditches are generally built by contractors who
are provided with ditching or dredging machines. In many
cases these are floating dredges which begin at the head of the
ditch and dig toward the outlet. There are other types of
ditching machines, which operate on tracks laid on each side
of the proposed ditch. These large machines remove the
earth from the ditch at a very reasonable cost, varying from
5 to 15 cents per cubic yard.

Disadvantages of Open Ditches. There are many dis-
advantages of t)pen ditches. Small ditches do not furnish
good outlets for the ground water because they cannot be
kept open to suflScient depth. It is to be noted that an open
ditch will not drain below the surface of the water in the
ditch. Again, open ditches interfere seriously with the culti-
vation of the land, and are very unsightly. They occupy
so much land as to make their upkeep expensive. Further-
more, more plant food is carried off by an open ditch than by
a tile drain. If the water must pass down through the soil
►re or less of the plant food will be left in

Open Ditch. As in the case of tile drains,
any attempts to prepare a formula which
to compute the capacity of open ditches,
many factors which influence the flow of

Digitized by

Google

DRAINAGE 105

water in ditches. One of the most important of these is the
cleanness of the ditch. A very Uttle rubbish, if allowed to
accumulate in an open ditch, will decrease its capacity materi-
ally. Grass and weeds may grow in an open ditch to such an
extent as to reduce the capacity of the ditch to less than half.

Fig. 67. An excavator for digging open ditches, which is carried on
trades laid at each side of the ditch.

The following tables computed by Kutter's formula will
be useful in this connection.* These tables are taken from

♦Kutter's formula for the velocity of flow in open ditches is as follows*
LSil + 41.65 + .:2028L

.00281 \ X y 1^1/

1 + /41.65 -^ .00281 )V~:^

in which v = velocity of flow in feet per second.

i = sine of the inclination of the slope, or the fall of the water surface in a

given distance divided by that distance,
r = area of the cross section in square feet divided by the wet perimeter

in lineal feet,
n = coefficient of friction for different sizes of canals and with different

degrees of roughness.

Digitized by

Google

106

AGRICULTURAL ENGINEERING

Bulletin 78 of the Iowa experiment station. A coefficient of
roughness of .03 has been used and they are for ditches having
the sides with slopes of one foot horizontal to one foot vertical .
The ditches are not to run more than 8-10 full, where the
capacity is mentioned. Above the upper heavy lines in
the table the % inch standard of water for 24 hours is used;
between heavy lines the J^ inch standard; and below the
lower heavy lines the J^ inch standard.

Number of acres drained by open ditches.
Depth of water 5 feet. Depth of ditch at least 6H f^t-

Grades

Average width of water

Per
cent

Ft.

per
mile

feet

8
feet

10
feet

16
feet

BO
feet

feet

60
feet

0.02

1.0

980

1470

1900

5000

7150

23800

43800

0.04

2.1

1390

2090

2800

7200

20400

33500

62500

0.06
0.08

3.2
4.2

1710
1980

2560
2980

5100
6100

17600
20400

24700
30000

40800
48800

75500
88000

0.10

5.3

2220

5010

7600

23400

83400

54500

98000

0.15

7.8

2720

6300

17100

28700

40500

66700

120000

0.20

10.6

4820

7300

19500

33000

47000

77000

139000

0.25
0.30
0.40

13.2
15.8
21.1

5370
5900
6830

16300
17900
20600

21900
23900
27700

37500
40700
47000

53000
57000
67000

86000
94000

155000
170000

0.50

26.4

7600

23000

31000

0.60
0.70
0.80
0.90

31.7
37.0
42.2
47.5

16700
18100
19000
20500

25200
27300

33900

•

Digitized by

Google

DRAIIfAGE
Number of acres drained by open ditches.

107

Depth of water 7 feet.

Depth of ditch at least 9 feet.

Grade

Average width of water

Per

Feet

60 ^

eeni

per mile

feet

0.02

1.0

2300

4700

16600

28000

48000

88500

0.04

2.1

4850

6740

23400

35400

58000

106000

0.06

3.2

5920

17000

29600

43400

72000

129000

0.08

4.2

6940

19100

34200

50000

83000

150000

0.10

5.3

7720

21800

38400

56000

92600

167000

0.16

7.8

19400

27000

47200

68500

112000

202000

0.20

10.6

22400

31300

54200

78700

130000

235000

0.25

13.2

25000

34800

60500

88000

146000

0.30

16.8

27400

38200

66200

96500

0.40

21.1

31700

44100

0.50

26.4

35400

QUESTIONS

1. When may it be necessary to use open ditches as drains?

2. What are some of the disadvantages of open ditches or drains?

3. What slope is usually given the sides of open ditches?

4. What is the "waste bank"? The "berm"?

6. How much does the digging of open ditches cost per cubic yard?

6. What factors influence the capacity of open ditches?

7. What formula is generally used in computing the capacity of
open ditches?

Digitized byVjOOQlC

CHAPTER XVII
DRAINAGE DISTRICTS

Definitions. The drainage district is an organization of
the owners of land for the purpose of constructing and main-
taining a drainage system where the cost is to be shared in
proportion to the benefits derived. Such an organization is
necessary where an individual cannot drain without involving
the use of the land of his neighbors. A drainage district
may include at least three classes of land: First, all of the
adjacent land which in itself may not be in immediate need
of drainage; second, land in partial need of drainage; and
third, worthless land which would be reclaimed by drainage.

In every drainage district there are two kinds of work:
First the co-operative work, such as the construction of large
drains or ditches; second, the individual work required by
land owners in supplying laterals or submains.

Drainage Laws. The organization of drainage districts
is a matter which involves many details and which is subject
to special laws in most states. These special drainage laws
usually cover the essential steps of procedure; and the
features of the organization of a drainage district are as
follows: First, the right of the property owners to petition
for the construction of drains alleged to be of pubUc benefit.
Second, provision for making and collecting assessments, as
well as the appraisement and payment of damages. Third,
the estabUshment of the perpetual right of land owners to
the use of the drains which are to be constructed in the
district. Fourth, the authority to obtain money by incur-
ring debt or selling bonds, under the proper legal regulations.

108

Digitized by

Google

DRAINAGE 109

Survey and Report. After a petition has been made for
the formation of a drainage district, the law places the matter
of a survey and report of the district in the hands of a board
or an officer of the law to order the survey and report by an
engineer. This report should be comprehensive in extent,
and should furnish sufficient data concerning the district to
enable the board or the officer of the law to determine whether
or not it will be of benefit to the district as a whole.

The report in this case should include an estimate of the
cost of the work to be performed in the district, covering the
actual cost of the construction of the drains and the neces-
sary work in connection therewith, such as construction of
bridges, etc. It should include an estimate of damages to
all property owners which may be incurred from the con-
struction of the drains; also estimates of the cost of the
engineering, of fees of the commissioners, and of all legal
expenses arising from the suits which may be carried to court.

Damages. Provision is usually made for a commission
of disinterested men to appraise the damages which may come
to the individual property owners through the construction
of the drainage work. Sometimes this board of commis-
sioners is also called upon to levy the assessment of benefits.

Assessment of Benefits. It is usually provided by law
that the total cost of the drainage district shall be assessed
according to the benefits derived. These benefits may be
either specific or general; specific in that the value of the land
may be increased, and general in that the health of the com-
munity is improved by the drainage district.

There are many things involved in levying an assessment,
and these are more or less subject to state laws. Copies of
drainage laws may be obtained by applying to the secretary
of state in any state, and these laws may be made the subject
of an interesting study.

Digitized by

Google

110 AGRICULTURAL ENGINEERING

QUESTIONS

1. What is a drainage district?

2. When is a drainage district necessary?

3. What three classes of land may it include?

4. What two kinds of drainage work does it include?

5. What are the four essential features of laws relating to drainage
districts?

6. What is required in the siurvey and report of a drainage district?

7. What does the cost of a drainage district include?

8. Describe the assessment of damages in a drainage district.

9. What is meant by assessment of benefits?

REFERENCE TEXTS

Engineering for Land Drainage, by C. G. Elliott.
Practical Farm Drainage, by C. G. Elliott.
Land Drainage, by Manley Miles.
Lrigation and Drainage, by F. H. King.
Notes on Drainage, by E. R. Jones.
Bulletins of U. S. Department of Agriculture.
Bulletins of state experiment stations.

Digitized by

Google

PART THREE— IRRIGATION

CHAPTER XVIII
fflSTORY, EXTENT, AND PURPOSE OF IRRIGATION

Control of Soil Moisture. Attention has been called to
the importance of having the soil contain the proper amount
of moisture to furnish the best conditions for the growth of
crops. Plants require that the soil contain a sufficient amount
of moisture, not only to dissolve the plant food, but also to
enable them to absorb and assimilate it. Much of the plant
food in the soil is made available through the action of micro-'
scopic organisms. The vitality of these organisms depends
largely upon an adequate supply of moisture. As has been
explained, drainage is for the purpose of relieving the soil of
a smplus moisture; on the other hand there may be in certain
locaUties at times and in other locaUties at all times a defi-
ciency of moisture from natural sources. Irrigation is simply
a process of supplying water to the soil by artificial means,
either to make it possible to grow crops or to increase pro-
duction.

Irrigation, then, is the reverse of drainage; and although
this be true, it is to be noted that irrigation practice has
many features in common with drainage. The management
of water is much the same, regardless of whether it is to be
removed from the soil as in the case of drainage or suppUed
to the soil as in the case of irrigation.

The importance of irrigation may be made clear by calling
attention to the fact that many crops, Uke potatoes and com,

111

Digitized by

Google

112 AGRICULTURAL ENGINEERING

during the part of the growing season when the tubers or
ears are forming, require a large amount of plant food and
moisture. At this time the plants have a wonderful root
development, absorbing a great amount of soil moisture; and
if maximum yields are to be secured, sufficient moisture must
be suppUed.

History of Irrigation. The practice of irrigation runs
back even before the time history began to be written.
There is evidence that irrigation was practiced along the
Nile and the Euphrates rivers more than 2000 years b. c.
There were also large irrigation works in Baluchistan and
India before the Christian era. Many of these ancient works
have been abandoned, yet not a few have been maintained
and are still in use. In the Western Hemisphere, irrigation
was practiced at a very early date in Peru, in South America,
ai^d by the Aztec civilization in North America. The
remains of ancient irrigation works are to be found in parts
of Arizona and New Mexico.

Settlers in the vicinity of San Antonio, Texas, began to
practice irrigation as early as 1715. When the Mormons
settled in the Salt Lake Valley in 1847, they soon began to
give attention to the matter of irrigation, and much credit
for the development of irrigation methods should be given
to these pioneers. As early as 1870, a colony known as the
Greely Union Colony was established in northern Colorado,
and began the construction of works for irrigation. Since
that time irrigation has grown by bounds in the United
States.

Dr. Elwood Meade, former Chief of Irrigation Investiga-
tions, U. S. Department of Agriculture, has estimated that
the area now under irrigation in countries from which it is
possible to secure reliable statistics, aggregates 85,000,000
acres. Taking into account countries which do not have

Digitized by

Google

IRRIGATION 113

statistics, he estimates that the total irrigated area is not far
from 100,000,000 acres, or about the area of the state of
California. This area is being rapidly increased.

Professor F. H. King states in his book, "Irrigation and
Drainage," published in 1907, that the area irrigated in
India was about 25,000,000 acres, in Egypt about 6,000,000
acres, in Italy 3,700,000 acres, in Spain 600,000 acres, and
in France 400,000 acres.

The following data are taken from the preliminary report
of the United States Census of 1910. These figures are for
the arid states of the United States, and do not include rice
irrigation.

Total acreage irrigated in 1909 13,739,499 acres

Area irrigation enterprises were capable of irrigating

in 1910 19,355,711 "

Area included in irrigation projects 31,112,110 "

Total cost of irrigation systems constructed $304,699,450

Average cost per acre (based upon construction to July 1,
1910, and acreage enterprises were capable of supply-

ingin 1910) $15.76

Average annual cost per acre of maintenance and opera-
tion $1.07

PURPOSES OF IRRIGATION

To Supply Moisture. By far the most important pur-
pose of irrigation is to supply moisture when needed for plant
growth, as has already been explained. In some localities
crops cannot be grown at all without irrigation, and in others
irrigation is practiced in order to supplement rainfall and
increase the crop.

To Control Temperature. In some localities irrigation is
practiced chiefly to control the temperature. Cranberry
marshes are often flooded with water to protect the crop from
frost. In other localities the soil is warmed in winter by

Digitized by

Google

114 AGRICULTURAL ENGINEERING

causing a thin sheet of water to flow over it, and the same
process may have a cooling effect in simmier. This Mnd of
irrigation is practiced in Italy where a supply of warm water
is obtainable.

To Kill Weeds. In rice fields the surface of the ground
is flooded in some instances largely for the purpose of kiUing
weeds, thus reducing the labor of cultivation. Such a
system also protects the crop from the ravages of burds and
insects.

To Supply Fertility. Irrigation may be practiced in some
localities in order to supply additional fertility to the soil.
Some irrigation water carries a large amount of sediment
which is very rich in plant food. The water may also con-
tain soluble plant food, as phosphoric acid, potash, and
nitrogen. The fertility of the land along the Nile, in Egypt,
which has been irrigated for ages, is maintained largely by
the addition of fertility through the irrigation waters.

It is true that some water supplies cannot be used for
irrigation, because they contain poisons injurious to plants.
This is often true of the water of rivers into which the refuse
from smelters and certain kinds of factories is discharged.

Disposal of Sewage. In many instances the disposal
of sewage waters from cities has not only been facilitated,
but also made a matter of profit, through irrigation. Sewage
water, when applied to the soil is quickly purified and made
harmless. Sewage water is usually very rich in plant food.

QUESTIONS

1. Define irrigation.

2. Why is an adequate supply of moisture in the soil important?

3. How long has irrigation been practiced?

4. How much land in the world is now irrigated? In U. S.?
6. What is the main purpose of irrigation?

6. Name and describe four other purposes of irrigation.

Digitized by

Google

CHAPTER XIX
IRRIGATION CULTURE

The Amount of Water Required for Crops. As expltdned
in the part of the text devoted to drainage, nature does not
in all cases supply the amount of water which will produce the
maxiTnum growth of plants. In this connection the question
of the amount of water which, when properly applied, will
produce a paying yield of crops, is one of vast importance
to those interested in irrigation. In most instances irriga-
tion water is expensive, and for the sake of economy no more
water should be used than necessary. The question, how-
ever, is very complex, and cannot be treated otherwise than
very briefly in this text.

The water which comes to the soil leaves it in three dif-
ferent ways: First, a portion of it is transpired through
plants; second, a portion evaporates from the surface of the
soil; third, a certain amount of the water flows away over the
surface or as underground drainage. Plants grow by using
water, as described under the first head. The other two
ways in which the water leaves the soil may be considered
losses, and should be reduced to the minimum.

There are many conditions which modify the amount of
water required for irrigation. These may be enumerated as
follows.

The Nature of the Crop Grown. Some crops transpire
more than others, because they have more foliage to give
ofif the moisture. The root growth of the plant is a factor in
determining the amount of moisture used, as the roots of some

115

Digitized by

Google

116 AGRICULTURAL ENGINEERING

plants strike deep and are thus able to draw moisture from
a larger volume of the soil.

Character of the Soil. The amount of water required is
dependent largely upon the character of the soil; thus the
soil may be so open or porous as to permit a rather large loss
of moisture by seepage. The character of the soil influences
to a rather large extent the effectiveness of the soil mulch
which conserves the moisture in the soil, which is to be
described later.

Character of the Subsoil. The character of the subsoil
is a factor in determining the amount of water required by
the plant, for an open subsoil will be the means of a great loss
of moisture by percolation downward.

Effect of Cultivation. Cultivation for maintaining a soil
mulch will influence to a large extent the amount of moisture
required for most satisfactory plant growth. In dry-farming
locaUties, as well as elsewhere, moisture is conserved by keep-
ing a dust mulch, or fine layer of soil, over the surface. Much
of the moisture in the soil available for the growth of plants
may be retained in this way from one wet season through a
dry season. After a rain or an appUcation of irrigating water,
it is customary to cultivate the soil as soon as practical in
order to form this mulch.

Closeness of Planting. A dense, heavy crop that shades
the ground will check the loss of moisture by evaporation.
Thus it is customary to irrigate grain crops most thoroughly
at the time when they are heavy enough to shade the ground.

Character of Rainfall. The character of the rainfall is an
important factor in fixing the duty of water; one heavy rain
which penetrates the soil to a considerable depth is more use-
ful than several Ught rains which are quickly evaporated.
Thus locaUties which have a wet season are often able to

Digitized by

Google

IRRIGATION

117

grow crops, even though the actual rainfall is quite small,
inasmuch as it may be stored in the soil and conserved by
cultivation for use during the dry season.

Frequency of Applying Water. In like manner the fre-
quency of applying irrigation water is a factor which deter-
mines the duty of water. One good thorough irrigation,
xmder most conditions, is preferable to several light appli-
cations.

The Amount of Water Used in Irrigation. It is to be
expected that the student is anxious to know how much
water must be applied to the soil to supply the plants where
the rainfall is not sufficient, or where the rainfall is too slight
to be considered. The amount of water is usually designated
in inches or feet. This means that the water applied is
sufficient to cover the entire surface to a depth indicated in
inches or feet as occasion may require. The actual amount
of water varies largely, as may be expected.

Mr. H. M.Wilson, in "Manual of Irrigation Engineering,"
gives the following table setting forth the amount of water
used in irrigation in different countries.

Amounts of waier used in irrigation in various countries.

Name of country

No. of acres per
second foot •

No. of inches per
10 days

Northern India

60 to 150

65 to 70

80 to 120

60 to 120

80 to 100

70 to 90

60 to 80

100 to 150

150 to 300

3.967 to 1.587

Italy

3.661 to 3.4

Colorado

2.975 to 1.983

Utah

Montana

3.967 to 1.983
2.975 to 2.38

Wyoming

3.4 to 2.644

Idaho... '^

3.967 to 2.975

New Mexico

3.967 to 2.975

Southern Arizona

2.38 to 1.587

San Joaauin VaUev

2.38 to 1.587

Southern California

1.587 to .793

*See Chapter XXI for definition of this unit.

Digitized by

Google

118

AGRICULTURAL ENGlUfEERING

Dr. Elwood Meade furnishes the following table as the
duty of water for different crops in the United States:

Depth of ivater used for different crops and the irrigation season for eath.

Crop

Depth of Irrication.
Feet

Irrigatins seMon

Potatoes

3.94
3.39
2.76
2.68
2.15
1.73
1.49
1.40

May 17, to S^t. 16
April 1, to Sept. 22
April 15, to Sept. 2
April I, to July 26
July 13, to Aug. 17
May 22, to Aug. 20
June 12, to Aug. I
July 24, to July 29

Alfalfa

Orchard

Wheat

Sugar beets

Oats

Barley

Com

CtQps Grown by Irrigation. Most farm crops can be
grown successfully by irrigation methods, and no attempt
will be made here to discuss all. It is desirable, however,
to discuss some of the chief crops grown in this way.

Grain. One of the principal crops grown by irrigation is
grain, and it is one which adapts itself well to irrigation
methods. When land is brought under irrigation, grain is
usually one of the first crops to be grown. There are several
reasons for this. Cereals are food crops and are always in
demand. They do especially well on virgin soil and they
require the least output in preparing the land. Furthermore,
grain is an excellent crop to prepare the land for other crops
to follow later.

In most localities there is enough moisture in the soil to
start the grain at the beginning of the growing season, and the
nmnber of times that irrigation water must be appUed will
depend upon the factors which have been described. In
some localities along the Pacific coast and in New Mexico
and Arizona it may be necessary to apply irrigation water
during the winter or nongrowing season. In other localities

Digitized by

Google

IRRIGATION 119

where thare is sufficient rainfall to start the grain, irrigation
is not practiced until the grain is six or eight inches high. It
is generally considered better, however, if it is found neces-
sary to irrigate near the time of planting, to irrigate before
planting rather than after.

On light soils with free underdrainage it may not be
possible to retain the moisture through the winter season,
in which case irrigation should be practiced near the time of
planting. It is to be noted, however, that in some localities
it may be advisable to irrigate after planting, in order that
the time of planting may not be delayed. The principal
. danger in irrigation after planting lies in the formation of
crusts. When the crust forms it must be either softened
with a subsequent irrigation or broken up mechanically by
means of special rollers or peg-tooth harrows.

It is considered best not to fiunish so much water as to
grow a large straw crop. Heavy straw crops make a large
demand upon the soil moisture, and are not essential for
large crops of grain. Grain is also likely to be of more value
when grown on straw that does not have a rank growth. It
is customary, then, to dispense with as much irrigation during
the growing season as is possible without lowering the
vitaUty of the grain.

In some localities only one irrigation is necessary, and this
is given at the time when grain is in the milk stage. It
seems quite important that the grain ^be supplied with
abundant moisture at this time. In other locaUties where it
is quite dry and where the conditions of soil and climate
require it, two or more irrigations may be given.

Alfalfa. One of the great crops of the irrigated land in
the United States is alfalfa. Like grain, if an ample supply
of moisture is given to the soil before the seed is sown,
there will be Uttle need of another early irrigation. If the

Digitized by

Google

120 AGRi CULTURAL ENGINEERING

land be irrigated following the sowing of the seed, the same
diflScnlties will be encountered as in the case of grain.

The first thorough irrigation is usually given after the
crop shades the ground. After the first crop is harvested,
each subsequent crop is irrigated, as a rule, but once. Prac-
tice as regards the time of this irrigation varies in different
localities. Sometimes the water is applied perhaps a week
or ten days before the time of cutting. The intervening
time is necessary in order that the soil may be dried out suffi-
ciently to enable the mowing machine and hay tools to
operate successfully. In other locaUties it is practical to cut
the crop first and apply the water afterwards.

Potatoes. Favorable conditions for the growth of
potatoes are to be found generally throughout the irrigated
regions in the United States. In the irrigation of potato^,
care should be used not to irrigate oftener than is necessary,
as a low temperature is produced which is unfavorable to the
growth of potatoes. For this reason the minimum of water
is suppUed, imtil the time for the formation of the tubers.
Potatoes seem to thrive best when the irrigations are few
but thorough, and cultivation is practiced to retain the
moisture between irrigations.

Sugar Beets. About two thirds of the beet sugar
produced in the United States comes from the irrigated
sections, and it is one of the crops which can be very success-
fully grown by irrigation methods. Sugar beets are grown
over a rather broad range of soils, and irrigation practices
vary widely with different localities. Where the soil is open
and the winter season especially dry, winter irrigation is
practiced; but where there is sufficient amount of moisture
in the soil to start the crop, irrigation may be omitted
entirely before the time of seeding. The first irrigation is
generally delayed as long as possible, or as long as the beets

Digitized by

Google

IRRIGATION 121

are making a steady growth. Two or four applications are
usually made during the growing season. The time of these
appHcations is determined by the condition of the plants.
Just as soon as they begin to suffer for want of water it is
applied. The last application usually comes within four or
six weeks before the harvest. This final irrigation is one
that requires considerable skill in order that it may be given
at the proper time; for if beets are allowed to mature too
soon the sugar content will be low.

Orchard Irrigation. Orchard irrigation is a general
practice in certain regions. This no doubt is due to the fact
that irrigation represents intensive agriculture and is well
suited to the growing of fruits, both large and small, as the
value of the crop per acre is generally large. It is customary
in irrigation practice for orchards, to keep the moisture con-
tent of the soil high enough to insure favorable conditions for
the growth of the trees at all times. Methods vary more in
orchard irrigation than in any other. In some locaUties
the practice of thoroughly wetting the soil and conserving
the moisture by cultivation prevails. Sometimes pipes or
^milar conduits are used to give a constant supply of water
to the soil. Although the last system is not practiced to
any extent, it is common to find it in some locaUties.

QUESTIONS

1. In what three ways does soil moisture leave the soil?

2. In what kind of soil will moisture losses by seepage be greatest?

3. Discuss four factors th%t influence the amount of water required
in irrigation. *v

4. Why is thorough wetting better than many light applications?
6. How much water is required for the common crops in the United

States, as estimated by Dr. Elwood Meade?

6. Explain the general methods followed in irrigating grain,
alfalfa, potatoes, sugar beets, and orchards.

Digitized by

Google

CHAPTER XX
SUPPLYING WATER FOR IRRIGATION

Canals. One of the principal ways of obtaining irri-
gation water is by the diversion of natural streams by means
of canals. The design and construction of the canals vary
widely with localities; but in general the principles involved
are the same as those involved in the design of open ditches
or drainage canals, which have been considered in a previous
chapter. It is customary to compute the capacity of irri-
gation canals by Kutter's formula, which is given on page 105.

Diversion canals lead the water of a river away from its
natural course to the upper side of the area to be irrigated.
The essential engineering features of a canal consist in
securing such a grade as to insure a sufficient velocity of

Fig. 68. Riverside Canal in Colorado before the water was turned
in for the first time. This canal where shown is 18 feet wide at the
bottom.

122

Digitized by

Google

IRRIGATION 123

flow to get the necessary capacity and to keep the canal
clean, or, as usually stated, cause it to "scour."

The construction of a canal is an important matter. In
the early stages of irrigation practice in the United States,
most canals were made with earth embankment, but the
increase in the value of irrigation water has led to the intro-
duction of methods to prevent waste from the canals by
seepage. It is estimated that 47 per cent of the irrigation
water now used in the United States is wasted in this way,
and in some cases the losses rim as high as 85 per cent.

Some irrigation canals are ranked among the world's
greatest engineering achievements. The Cavour Canal in
Europe cost $20,000,000; its waterway is 66 feet wide and 12
feet deep, and it crosses the drainage lines of several rivers.
It passes under the Sesia River in a masonry siphon 820 feet
long. There are some large canals in Egypt and India.
Among them may be mentioned the Chenab Canal, which is
250 feet wide at the bottom and carries 11 feet of water.
The main canal is 400 miles long, and has 1200 miles of
tributary canals. It cost $10,000,000, and it is said to irri-
gate 2,645,000 acres of land. There are no canals in the
United States that will compare with it. The Bear River
canal in Utah cost $1,000,000 and waters approximately
100,000 acres. The Modesto-Turlock canal system of
California is designed to water 275,000 acres, and cost about
$3,000,000.

Reservoirs. Reservoirs, either natural or artificial,
obtained by the danmiing or storage of water in natural
watercourses, are often made the source of supply of water
for irrigation purposes, inasmuch as water which would
ordinarily be wasted is held in storage until needed. In
some localities reservoirs are quite necessary, as streams
furnish the minimum amount of water during the time when

Digitized by

Google

124 AGRICULTURAL ENGINEERING

irrigation water is needed most. Under other conditions,
reservoirs are little needed.

Forests are natural reservoirs to the extent that they hold
the snow in mountainous ooimtries and prevent a rapid sur-
face run-off of the water. In some localities the irrigation
water comes from glaciers, which have been found to regulate
the supply in a satisfactory and natural way. Thus the
maximum amoimt of water is fmnished when the weather is

Fig. 69. View of the Roosevelt Dam on the Salt River, Arizona.
(Bui. 235, Office of Experiment Stations.)

hottest and the requirements are the greatest. Sometimes
reservoirs are placed at the end of the canal in order that the
supply of water may be on hand near the land to be irrigated,
so that, if a sudden demand for water is made which will
exceed the capacity of the canal, the water from the reservoir
may be released.

Reservoirs have been used in connection with irrigation
since very early times. In India nearly ten million acres of

Digitized by

Google

IRRIGATION 125

land are now irrigated from reservoirs. In Ceylon, the
Padival Dam is 11 miles in length, and 200 feet wide at the
base, 30 feet wide at the crest, and 70 feet high in places.
This dam is said to have cost $6,327,100. It is further
stated that there are 5000 reservoirs in use in Ceylon. There
are many reservoirs in use in the United States, some of which
have been built by private parties, and others by the
government. One of the largest of these is the Roosevelt Dam
on the Salt River in Arizona. This dam, completed in
February, 1910, has a capacity of 1,824,000 acre feet of water.

Pumping Water for Irrigation. In many places a supply
of irrigation water can not be obtained without the aid of
pumps. Usually water secured by this method is very
expensive, much more so than the water obtained from
canals and reservoirs by gravity. There are, however,
certain advantages in pmnping the water for irrigation pur-
poses. Generally the water supply is under perfect control,
which is not always the case with a canal or reservoir. Again,
there can be no controversies over water rights or friction
with other irrigators who want to use the supply at the same
time.

Underground water is the only source of supply in certain
localities. In some places in the West the soil is so open that
large streams disappear and flow away underneath the sur-
face. When this water can be pumped it forms a valuable
supply of irrigation water. In Egypt much of the water is
elevated by hand labor either from canals or from the river
Nile. In California alone, over 200,000 acres are irrigated by
water which is pumped, and some 400,000 acres are so irri-
gated in Texas and Louisiana. There has been a marked
development in pumps during the past few decades. The
power used includes animal power, steam engines, gas and
gasoline engines, and electric power.

Digitized by

Google

126 AGRICULTURAL ENGINEERING

The cost of pumping water in certain parts of the United
States has been carefully studied by the United States
Department of Agriculture. In Santa Clara County,
California, the cost of pumping water was investigated at
60 pumping plants. The average amount of water pumped
per acre was 1.13 feet. The average cost of fuel and labor
was $4.96 per acre, and the fixed charge* was $5.20, making
the average cost of pimiping water $10.16 per acre. The
average efl&ciency of the pumps was 41.16 per cent. It was
found that the cost of pumping was reduced by an increase
in the size of the plant. The cost of power varies with the
cost of the fuel. In some localities the steam engine is
cheaper than gas or gasoline engines, and in others the
reverse is true. Electricity is more convenient than any
other power; but, unless it can be furmshed through a water
power plant or some other cheap source, it is the most
expensive. In Arkansas and Louisiana the irrigation water
for rice culture is pimiped by steam. The following table is
the smnmary of the cost of pumping water at 17 plants in
Louisiana and Arkansas, as reported in Bulletin 201, Office
of Experiment Stations. The general difference in cost at
the Louisiana plants and those of Arkansas is due primarily
to the Uft or height the water had to be pimiped. In the
Louisiana plants the Uft was about 20 feet, and in the
Arkansas plants about 40 feet.

Windmills are used quite extensively in certain localities,
principally in Kansas and CaUfomia. An investigation of
the cost of windmill irrigation at Garden City, Kansas,
indicates that the cost per acre was $2.35. Owing to the
fact that power is obtained in small units and the cost of
installation and maintenance is very high in the case of wind-
mills, it is doubtful if they will be used extensively.

* Covering all other expense, such as interest, depreciation, eto.

Digitized by

Google

IRRIGATION

127

® m H

III

OCOOSC^»OCO

1-i !>; lO !>; O !>;

t>; lO 00 O t>^ CO t^

^ Oi CS| ® p !>: '^
C^ * »M fH C^ »-* »-*

CO CO WD X 00 •* WD
O Oi CSJ t> p CO CO

csi c4 rj5 ^ c<i c<i w

CO Tt< <© »H ^ Q «

CO c^ csj c^ q «5 oi
* 1-J CO CO CO c4 ci

gCOWDSO^OOQ
^ CO i-J 00 00 CO WD

OS l>^ O 00 t^ WD t^

TT O CO l> ^ CO C
»-* CO C^ i-H »-H »-l C

8SS:

COrJ^COi

g3'c<rTjrcoc^"c4'co

^ _ )N<

> CO "Tt< CO WD W5 I

Sooocsio3csi

CSi CO -^ WD CO t* 00

a Or-

Is-

J2o»c^*'-'Oi>c>c6cdi-H

S^J?

9^ OS

WTt<WDOQI^t^QQO
C^OWDOOOOfhoOOOi-h

cdc6cicoc4'-5'-<'^c6wD

cioi'^c6c<ic6wDWDo6cd

8WOOCOCOOCOCOCO'$
00rt<OiCOWD'-J0qWDCO

dcidcooicooiNb^co

Th (N CO <N <N rH rH e^ (N CO

wdc<iowqowdoqwd

rtiO»=Ht>.O'*'Ht^00WD

fH fH C^ fH

SOOOiCOrHOQWDQ
OWDCOcOTt<©QpO
00 1-H CO Oi Oi^N^^CO C^^WD^

fh c<f CO F-ToTco cf i-Tc^Tco

SoqwDSwoqc^ippq

I>WDI>0>i-hc6"^c4'-hWD

C^COCOC^W^COCOCOWDWD

OiO'-HCSICO'^WDCOI^OO

O 00 00 00 CO O WD OS 0> 1-1 Oil
00 00 1-1 WD p CO Ol 00 p 00 CO

cdcOWD-^WDWCOCO-^d -^

^
s

OS
CO

Digitized by

Google

128 AGRICULTURAL ENGINEERING

QUESTIONS

1. How are canals used to secure a supply of irrigation water?

2. Why is the construction of a canal important?

3. Name some of the largest famous irrigation canals.

4. What are the purposes of irrigation reservoirs?

5. How do forests act as reservoirs for irrigation waters?

6. Describe some of the largest irrigation reservoirs which have
been constructed.

7. What advantage has piunping over other means of supplying
water?

8. How much does it cost to piunp water for irrigation under nor-
mal conditions?

9. What can be said of windmills as a source of power for pumping
irrigation water?

Digitized by

Google

CHAPTER XXI
APPLYING WATER FOR IRRIGATION

Principles Involved. In applying irrigation water, con-
sideration should be given to some of the principles govern-
ing the wetting, puddling, and washing of the soil. If these
points are not studied in connection with each type of soil,
much more water may be used than necessary, and it
may be used in a way harmful to the crops. A good
irrigation farmer observes closely the effects of the appli-
cations on the soil and plant, and continually endeavors
to improve his methods. When water is applied to the
surface, it starts to percolate downward and outward. If
the soil be coarse, the water will travel almost directly down-
ward, especially if the texture becomes more open or coarser
as the depth increases. It is then necessary to apply the
water to the entire surface to get the best results. When
water is applied to a fine loam underlaid by a subsoil of very
fine texture, the water percolates downward slowly by grav-
ity and spreads laterally by capillarity. For this reason the
water may effectively be appUed to these soils in furrows
some distance apart.

When the soil is very dry, the percolation downward is
less rapid than when it is more moist. This is accoimted for
by the fact that the air in the soil must be displaced before
the water can travel downward. This takes time, and for
this reason a soil will not take water as rapidly when dry as
when moist.

In applying irrigation water,* great care should be taken
not to puddle the soil, that is, to cause the crumb structure w

5^ -15>Q

Digitized by

Google

130 AGRICULTURAL ENGINEERING

be SO broken down as to allow the soil particles to run to-
gether and form a compact mass. Soil in such a condition is
said to be water-tight. The air cannot enter a soil of this
kind, and an aerated soil is essential in furnishing favorable
conditions for plant growth. If too much water is applied
to the soil, it becomes water-logged and suffers for the lack
of air in the same way.

Preparing Land for Irrigation. As irrigation water is
usually applied by the aid of gravity, great care should be
used in preparing the surface ground and the ditches and
small laterals necessary to convey the water over the fields.
The proper slope must be given to the surface to give an even
distribution of the water. For this reason one. of the largest
items of expense involved in bringing land under irrigation is
the cost of preparing the land. Usually irrigable land is
covered with some sort of growth which must be removed.
It costs from $1.50 to $4 per acre to remove sage brush, which
is usually found on the land in the arid sections of the United
States. The land must be thoroughly gone over with graders
and other leveling machines and worked until the surface is
made a perfect plane.

Dr. Elwood Meade states that the cost of preparing the
land for irrigation in the United States varies from $3 to $30
per acre. The following table shows the average cost of
preparing land for different methods of irrigation:

Check method $ 3.60

Flooding method 2.75

Furrow method 3.50

Basin method 4.50

Methods of Applying Water. There are many methods
of applying water to irrigated crops, and nearly all are
practiced in the United States. The method to be used in
any particular case depends largely upon the nature of the

Digitized by

Google

IRRIGATION

131

Fig. 70. Flooding: method of irrigation.
(Sep. 614, U. S. Dept. of Agr.)

ground, the crops grown, the amount of water available, kind
of soil, and other conditions.

The Flooding Method. One of the more general methods
of application is known
as the flooding system.
It is generally used on
land when it is first re-
claimed, even though
another method is in-
tended to be used later.
Preparing the ground
for flooding consists in
leveling, grading, and smoothing, so that the water will
flow readily over it in sheets. To distribute the water, small
field ditches, or laterals, are located along the best routes.
These small ditches are usually from 50 to 100 feet apart,
and they generally follow grade Hnes, or contours. Where
ms sxa" little care is used to control the flow
of the water, the practice is said to be
''wild flooding." The small ditches
are made with a double moldboard
plow, which turns a furrow on either
side. To cause the water to overflow
from the ditch to the side, a dam
must be put in place. This con-
sists usually of a piece of canvas
nailed along one edge to a strip of
wood. In other cases, the ditch may
be dammed by simply building up a
small ridge of earth across the ditch.
The Check Method. The check method of applying
water consists in dividing the fields into sections each having
a comparatively level surface and bordered on all sides by

Figr. 7i. A canvas dam.
This dam has an opening
to divide an irrigating
stream. (Bui. 203, Office
of Experiment Stations.)

Digitized by

Google

AGRICULTURAL ENGINEERING

low, flat levees, or ridges.
Into these checks the
water is turned. On level
ground these sections or
checks may be made rec-
tangular; but on sloping
ground the ditch for sup-
plying the water must fol-
low the contour lines, in
which case they are said

Fig. 72. A canvas dam in use. (Farm- j,^ i _ «^^4.^„« «U««U«
er's Bui. 392, U. S. Dept. of Agr.) tO DC COUtOUT CheCKS.

In applying the water,
an opening is made from the ditch into the side of each
check and the water
allowed to flow in
until each is covered
to the desired depth.
Where the check
method is followed,
it is customary to
have small wooden
outlets from the ditch

^_ - , . , Fig. 73. Check method of irrigation. (Sep. 514,

mto the checks, with u. s. Dept. of Agr.)

valves which can be
operated to close the
opening when de-
sired.

Basin Method.
The basin method is
quite similar to the
check method. It
is used principally

F^g. 74. Basin^meth^od^of Jrri^U^on. (Sep. 514. j^ ^j^^ irrigation of

Digitized by

Google

IRRIGATION

133

Fig. 75. Border method of irrigation.

trees. A basin is provided around the tree, with a suitable
ridge to hold the water, which is then turned in until a suffi-
cient amount is applied.

Border Method. The border method is also similar to
the check method in
that the land is di-
vided into long strips,
and the water is
turned into these
from a ditch at the
end or along the bor-
der. It is easy to
see that by arranging
these long strips the work necessary in preparing ridges is
reduced.

Furrow Method. The furrow method of applying irri-
gation water consists in turning the stream of water into
furrows between the rows of intertilled crops. It is more
generally employed than any other method, with the excep-
tion of flooding from field laterals. The distance between
furrows will depend upon the character of the soil. It is
customary to provide small openings or pipes in the ridge

at the side of the
supply ditch by
which the water may
be turned into the
furrows.

Subirrigation.
Upon first thought
it would seem that
subirrigation, or wa-
ter applied to crops from pipes laid beneath the surface,
would be an ideal system. This is not the case, as such a

Fig. 76. Manner of placing tubes in ditch
bank for furrow irrigation. (Farmer's Bui. 373,
U. S. Dept. of Agr.)

Digitized by

Google

134 AGRICULTURAL ENCflNEERING

system is not only expensive to install, but also quite extrav-
agant in many cases in the use of water. This is due to
the fact that the water tends to percolate downward from
the opening and so does not saturate the soil satisfactorily.
Spraying Method. Where irrigation is practiced in a
small way the water may be appUed by spraying. This
system provides sin^ace pipes containing water imder
pressure, whch may be discharged through nozzles in such a
way as to cover the entire surface. Often the pipes are
arranged so as to revolve, turning the nozzles about in such
a way as to discharge in different directions and thus reduc-
ing the amount of pipe required.

The Measurement of Water. Most of the water used
in irrigation is sold to the farm owners, which fact necessi-
tates that methods be devised for its measurement and regu-
lation. In addition,
the irrigator should
know something defi-
nite about the amount
of water applied, in
order that he may de-
termine whether or
not it is being used as
efficiently as it should
be.

Units of Measure-
ment. One of the most

FlK. 77. A Cippoletti weir with water regis- satisfactory imitS of
ter in place for measuring and recording the «"'«*«*'*^»^*j **** ^^ '^'■
head of water over the lower edge of the weir. mboGiirckmfknf frrnn f Via

(Bui. 86. Office of Experiment Stations.) measurement irom ine

standpoint of the agri-
culturist is the acre-inch, which is the amount of water required
to cover an area of one acre one inch deep. Thus, ten acre-
inches is sufficient water to cover an acre ten inches deep.

Digitized by

Google

IRRIGATION 135

or ten acres one inch deep. The principal advantage of this
unit lies in the fact that a direct comparison may be made
between the irrigation water applied and a similar amoimt
of rainfall. Where water is delivered from a canal, it is
necessary to use a miit which will indicate the rate of delivery.
The cubic foot per second is a unit in common use, and is
easily imderstood. The miner's inch, used in many states,
is a unit whose value varies very much. In Idaho, Nevada,
and Utah, laws have been enacted defining a miner's inch
as 1-50 of a cubic foot per second. In Arizona, it is 1-40
of a cubic foot per second, and in Montana a unit having
the same value is called a statute inch instead of a miner's
inch. In Colorado, a cubic foot per second is equal to 38.4
statute inches. Water is usually measured by weirs, which
are notches of a certain form through which the water is
allowed to flow. A form of weir in general use is known as
the CippoUetti. The amount of water flowing through such
a weir may be determined from the height, or "head," of the
flow.

QUESTIONS

1. What are some of the principles involved in applying irrigation
water?

2. What are some of the essential features of preparing land for
irrigation?

3. How does the cost of preparing land for irrigation vary with
methods of irrigation?

4. Describe the flooding method of applying irrigation water.

5. Explain the check method of applying water.

6. Describe basin and border irrigation.

7. How is irrigation water applied in furrows?

8. Why is subirrigation not generally satisfactory?

9. How is irrigation water applied by spraying?

10. What are the units in general use for measuring irrigation
water?

11. What is a weir?

Digitized by

Google

CHAPTER XXII

IRRIGATION IN HUMID REGIONS, AND SEWAGE
DISPOSAL

Irrigation is generally practiced in those regions where the
natural rainfall is so small as to make it quite impossible to
grow crops without supplying water artificially. Here irri-
gation is an absolute necessity. In other localities, it may
not be a necessity, but it may be practiced profitably to sup-
plement rainfall, thus securing larger yields. As agriculture
becomes more intensive, it is to be expected that irrigation
of this nature will become more common.

The regions in which the rainfall is very small are said
to be arid; those having suflScient rainfall to produce good
crops under normal conditions are said to be humid; and the
regions in which the rainfall is scanty or Hmited are said to
be semiarid. It is to be expected that supplementary irri-
gation will be practiced more in semiarid regions than in
humid regions. However, if a careful study be made of the
distribution of rainfall in many so-called humid regions, it
will be found that, in many years when the demand for
moisture is the greatest, the rainfall is insufficient. A study
of the rainfall at Philadelphia, by Mr. R. P. Teele, of the
Office of Experiment Stations, shows that, although the
average rainfall for that locaUty is large, the records indicate
that there were periods of drouth during 88 per cent of the
seasons for the 70 years covered by the investigations, which
dry spells caused injury to the crops that had short growing
periods. The investigations also showed that all crops
received too Uttle water during a third of the years.

136

Digitized by

Google

IRRIGATION 137

In Europe, irrigation has been practiced for ages in
regions having rather large rainfall. Meadows and pastures,
especially, are irrigated very successfully, and this is com-
monly practiced in Great Britain, Holland, Germany,
Switzeriand, Italy, and France.

In some countries where there is much sunshine, phe-
nomenal crops are grown through irrigation. It is reported
that in Italy, marcite, a meadow crop made up of a mixture
of clover and ItaUto rye grass, will yield from ten to fifteen
tons per acre of a cutting, for eight to ten cuttings per year.

There are many small irrigation plants through the humid
portions of the United States. Data collected by the irriga-
tion investigations of the United States Department of
Agriculture indicate that about 800 acres of meadow land
are irrigated in the humid regions of the United States.
Most of the water used is obtained from springs and through
the diversion of streams by small canals or dams. This
water is let over the meadows in small ditches or laterals, and
is spread over the same in a manner similar to the check
method of irrigation. Irrigation is also generally practiced
in the growing of small fruits, which are seriously injured
by drouths that come at the time when the fruit is forming.

The truck farmers have also found irrigation a profitable
insurance against loss through drouth. Professor F. H.
King, of the Wisconsin experiment station, conducted some
very interesting experiments in irrigation at Madison, Wis-
consin. Over a rather long term of years, the average
increase in the yields of grain was 26.93 bushels per acre.
The increase in the yield of clover hay was 23^ tons per acre;
and of potatoes, 83.09 bushels per acre. The cost of irrigat-
ing the land was $6.80 per acre, which cost did not include
the interest on the first investment for the plant. These
gwis are made up from the average yield for the State of

Digitized by

Google

138 AGRICULTURAL ENGINEERING

Wisconsin and therefore are no doubt large, inasmuch as the
nonimgated crops do not generally receive the attention
given to those which are irrigated.

Irrigation for Sewage Disposal. In many localities the
disposal of sewage water from cities is an important problem.
This is especially true of cities which are not situated near
large bodies of water or streams into which the sewage may
be discharged. In these cases, sewage irrigation must be

Fig. 78. Furrow irrigation with sewage water.

resorted to, and this not only provides a convenient method
of disposal, but it may be made a matter of profit. Perhaps
there is no way of disposing of sewage more satisfactorily
than by applying it to the soil. The organic matter in
sewage water is quickly purified through the agency of soil
organisms, when it is applied to the soil in a skillful manner.
The crops grown by sewage irrigation vary widely, an4

Digitized by

Google

IRRIGATION

139

include grasses, grains, potatoes and garden truck. Of
these, grasses is the most generally grown; Italian rye grass,
especially, thrives under this form of irrigation. The success
of sewage irrigation indicates that it could be practiced more
generally than it is at present.

For several years, experiments in sewage irrigation were
conducted at the Iowa experiment station, in co-operation
with the irrigation investigations of the United States Depart-
ment of Agriculture. The following table is a summary of a
part of the results obtained. Two plots of each crop were
grown under the same conditions, except that one was irri-
gated with sewage water and the other was not irrigated at all.

Summary of irrigation experiments in lowa^ shovnng increased yields by
the use of sewage water,

Kind of crop

Year

Yield per acre;
not irrigated

Amt. of

sewage

water

applied in

irrigation

Yield per acre

irrigated

area

Increase
yield per
A. by irri-
gation

Cabbage

Com

1907
1907
1907
1908
1908
1908
1909
1909
1910
1910
1910

63840 lbs.
67.8 bu.
41.4 bu.
3.15 tons
11.25 tons
150.2 bu.
29. bu.
6.67 tons
.13 tons
1.42 tons
39.1 tons

7 in.
7 in.
13.21 ft.
5.41 ft.
7.08 ft.

70430 lbs.
59.8 bu.
54. bu.

3.49 tons
12.75 tons
181.5 bu.
34. bu.

5.6

1.32 tons

3. tons
59. tons

9.5%
3.4%
30.4%
10.7%
13.3%
20.8%
17.2%

Barley

Rye grass

Beets, sugar ....

Potatoes

Barley

Alfalfa

—16.0%

Blue grass

Tiniothy

Beets

111.2%
60.9%

During the years 1907 and 1908, irrigation was given
only when the crop seemed to be in need of moisture. In
1910 a larger amount of water was used.

Digitized by

Google

140 AGRICULTURAL ENGINEERING

QUESTIONS

1. What is meant by humid, semiarid, and arid regions?

2. Why is irrigation profitable in humid regions?

3. How have experiments proven that yields may be increased in
humid regions?

4. Does irrigation furnish a satisfactory means of disposing of
sewage water?

5. What crops can be profitably grown with sewage irrigation?

REFERENCE TEXTS

Irrigation Engineering, by H. M. Wilson.

Irrigation and Drainage, by F. H. King.

Irrigation Institutions, by Dr. Elwood Meade.

Irrigation Farming, by L. Wilcox.

Primer of Irrigation, by D. H. Anderson.

Bulletins of the United States Department of Agriculture.

Digitized by

Google

PART FOUR-ROADS

CHAPTER XXIII
IMPORTANCE OF ROADS

History. The object of a road is to furnish a way for
travel and the transportation of products. The art of road
construction runs back before the time when history was
written, and roads have appeared in a country whenever its
people have shown a tendency to become civilized.

There is abimdant evidence at hand to show that a paved
road existed in Egypt as early as 4000 years b. c. No doubt
the material for the great pyramids was transported over a
part of this road. Much of the history of Carthage and
Rome relates to the construction of their roads, which were
used for the transportation of soldiers and supplies. The
success of the Roman Empire as a great nation is largely due
to its system of improved roads, over which its armies could
be moved quickly. Ancient Rome had no less than 372
great roads, aggregating about 50,000 miles, and which, it
has been estimated, would cost under modem conditions as
much as $5,000,000,000. All the civilized nations through-
out the world have given the matter of road construction
careful attention.

The Extent of Our Roads. There are in the United
States 2,150,000 miles of public roads. About one-half of
this mileage, however, is but little used, and no doubt in
time a part will be found unnecessary and will be discon-
tinued.

141

Digitized by

Google

142 AGRICULTURAL ENGINEERING

Benefits of Good Roads. The benefits of good roads to
agriculture are far-reaching and are worthy of careful and
extended study. The benefits are largely financial in char-
acter, and so the value of good roads may be estimated in
dollars and cents. There are other benefits which may be
styled social, and are those which tend to add to the comforts
of country life. '

FINANCIAL BENEFITS

Cost of Transportation. The most important and funda-
mental benefit to be derived from a system of good roads lies
in the reduction of the cost of transportation of farm and
other products which must be hauled over them.

Referring to Bulletin 49 of the United States Office of
Public Roads, it is found that diu'ing the crop year of 1905
and 1906 there were 42,743,500 tons of farm products, con-
sisting of barley, com, cotton, flax seed, hemp, hops, oats,
peanuts, rice, tobacco, wheat, and hay, hauled over the
roads from the farms to the shipping points. This estimate
does not include the transportation of products from the
town back to the farm, nor does it include Uve stock, truck-
farm products, and fruit. A careful investigation by the
Office of Public Roads indicates that the present cost of
transportation is about 25 cents per ton mile, that is, the
cost of hauling one ton one mile. If a small saving could be
secured in this cost of transportation per ton mile, the aggre-
gate saving for a year would be enormous.

With a system of good roads it is possible to make a great
reduction in this cost of transportation. The cost varies
with ttie kind of road. The investigation shows that over
broken-stone roads in good order the cost is only 8 cents per
ton; on broken-stone roads in ordinary condition, the cost is
11.09 cents; on earth roads, with ruts and mud, the cost is

Digitized by

Google

ROADS 143

39 cents; and on sandy roads, the cost is as much as 64 cents
per ton mile. The average haul for farm products in the
United States is about 9 miles. It is estimated by Mr. L. W.
Page, director of the United States Office of Public Roads,
that if the cost of hauling in the United States could be
reduced from 25 cents to 12 cents per ton mile, the annual
saving in moving the twelve principal farm crops would
amount to $51,000,000. He further estimates that the total
amount of freight hauled over country roads in a year
reaches 265,000,000 tons, and that the total cost of haul-
ing this on the roads approximates $500,000,000. In this case
the total saving in reduction of the cost of hauling from 25
cents to 12 cents per ton mile would be $250,000,000 annually.

In this connection, attention is called to the fact that it
would not be practical to improve all country roads. Mr.
Page estimates that the traffic is such that the cost of hauling
freight could be reduced to 15 cents per ton mile if 25 per
cent of the roads were improved. He estimates that the
total cost of improving this percentage of the total mileage
of roads would be $2,000,000,000.

A striking example of importance of country roads is set
forth by the fact that it costs the American farmer 3.06
cents more per bushel to haul his wheat crop a distance of
9.4 miles to market, than it costs to ship by regular steamship
lines from New York to Liverpool, a distance of 3100 miles.

Influence on Markets. Good roads have a decided
influence upon markets in several ways. First, a wider
variety of crops may be grown, and marketed at the center
from which good roads radiate. This tends to increase about
cities the area in which certain crops, such as fruit and
truck crops, can be grown. This is also true of dairying, as
a dairy farm can be located farther from the city, if good

Digitized by

Google

144 AGRICULTURAL ENGINEERING

roads are provided between the farm and the city, enabUng
the farmer to deliver his products quickly and cheaply.

Again, good roads permit the marketing of farm products
when the prices are most favorable. In many localities,
when prices are best the farmer is unable to deliver his
crops, owing to the fact that the roads are impassable.

Also, good roads furnish to the farmer a wider choice
of markets. With good roads prevaiUng, it is possible for
hun to deliver his products to any one of several centers.
Good roads tend to equalize the supply of produce on any
given market between favorable and unfavorable seasons of
production. Lastly, good roads tend to equalize local mer-
cantile business throughout the different seasons of the year.
In some instances little business can be done when the farmers
are unable to get into town on account of the bad roads.

Good roads tend to equalize railroad traffic. Often dur-
ing the period of bad roads, farm products are not deUvered,
and the railroads have Uttle to do. Then when the roads
become passable to heavy traffic, farmers sell their products
in such large quantities as to cause a congestion of traffic*.

SOCIAL BENEFITS

Social Benefits. Perhaps of equal importance with the
financial benefits to be derived from the system of good
roads are the social benefits. Good roads permit more easy
intercourse among country people, and between country
people and city people. Good roads place the farm nearer
the city, thus overcoming to a certain extent some of the dis-
advantages of country life. They are also a factor in assist-
ing in the development of the consolidated rural school, and
facilitate the rural mail delivery. The United States Post
Office Department will not estabhsh or continue a rural

Digitizes by

Google

ROADS 145

mail route where the roads are not maintained at a certain
standard.

Value of Farms. It is often stated that good roads tend
to increase the value of farms; and some instances are referred
to where, upon the completion of a good road past a farm, its
selling value was at once materially increased. No doubt
this can be considered the measure of the value of the bene-
fits which have been discussed.

Requisites of a Good Road. A good road is one over
which travel may take place with ease and comfort, and one
over which freight or products may be hauled at a low cost.
Furthermore, a good road must not be prohibitive in cost,
and must require a minimum of attention for its maintenance.
The following are some of the more important features which
should be considered:

Smoothness, No road can be considered a good road
unless it presents a smooth surface over which vehicles may
travel without jar or vibration. Smoothness is also essential
to the moving of loads with the least effort.

Rigidity. When a loaded vehicle rests upon a road sur-
face, the wheels sink into the surface more or less. If the
road surface is soft, the wheels will sink in deeply, and the
vehicle, as it is drawn forward, will be compelled to roll
against an incline. The amount of resistance which the load
furnishes varies with the depth that the wheels cut into
the surface. Thus, the road which will most prevent the
wheels from cutting in will furnish the least resistance.
' When a loaded vehicle is moved up an incline, it is noticed
that the resistance is increased proportionately to the grade.
Thus if a load of 1000 pounds be moved up a 10 per cent
grade, an extra force equal to 10 per cent of the load will be
required to overcome the resistance due to the grade. It is

Digitized by

Google

146 AGRICULTURAL ENGINEERING

here necessary to explain that a grade of 10 per cent is one
which has a rise of 10 feet in 100 feet of length.

Cost. A good road must not cost more than a certain
amount, or the value of its service will not cover the interest
on the investment. Thus the best road for certain conditions
may be one that is comparatively cheap, inasmuch as the
amount of traffic will not justify the expenditure for a more
expensive road. A good road will be durable, and will
require little attention to repair it. For this reason great
care should be used to see that the road is well constructed
and made of durable materials.

QUESTIONS

1. What is the object of a road?

2. What is the mileage of roads in the United States?

3. What two classes of benefits may be derived from good roads?

4. What is meant by the "ton mile"?

5. What is the average cost of transportation in the United States?

6. How does the cost of transportation vary with the kind of road?

7. In what way will good roads influence the markets?

8. How may good roads be of benefit in a social way?

9. What are the requisites of a good road?

10. How much money, according to the estimate of Mr. Page,
could be spent each year in the improvement of roads?

Note. The student should obtain statistics in regard to roads in
his own state, county, and township; the mileage, the funds spent, etc.

Digitized by

Google

CHAPTER XXIV
EARTH ROADS

Extent. Of the total mileage of roads in the United
States, about 2,000,000 miles are miimproved, or earth
roads. It is evident that a large percentage of these roads
will remain imimproved for a long time, and for this reason
earth roads are worthy of the most careful attention. By
the term ''earth roads" is meant roads made of native soil
and whose surface is loam or clay. Obviously the earth
road is the cheapest form of road. It is possible to construct
a fairly good road out of native soil, and such a road in most
cases furnishes the very best foundation for an improved
road with a hard surface of sand or gravel.

Construction of an Earth Road. The subject of earth
roads naturally divides itself into two divisions, earth-road
construction and earth-road maintenance. The first applies
to the preparing, constructing or building of the road, and the
last to its maintenance or repair.

Drainage. It is often stated that the construction of
earth roads consists primarily in providing adequate drain-
age. When considered in the broadest sense, drainage
would include not only underdrainage, but also surface
drainage. Underdrainage is quite necessary in any kind of
road, and especially in an earth road, and if not provided
natiwally it should be provided artificially. In constructing
earth roads it is desirable to maintain as liard a siu*face as
possible with the materials used, and water tends to soften
them. The supporting power of earth depends largely upon
the dryness of the soil. A good surface may be prepared, yet

147

Digitized by

Google

14S

AGRICULTURAL ENGINEERING

if there is water beneath it the water will come up by capil-
lary action and soften the road until its supporting power is
lost. Again, the action of frost is greater when the road sur-
face is full of water. Freezing causes the roadbed to expand
and heave, tending to soften it. Thus it is highly important
that soil in which the ground water stands within 3 or 4 feet
of the surface be drained with a tile drain. This is generally
accomplished by placing a line of tile at one side of the road,
under the side ditch, although sometimes it is placed beneath
the middle of the road. The former location is preferable
for several reasons. First, the ditch does not need to be as
deep. Second, in case of repairs the tile is easier to get at
than it would be if it were located underneath the middle of
the road; and, if it is found necessary to take it up, traflSc will
not be interfered with. Third, in a properly constructed
earth road the water which flows on the surface is conveyed
rapidly to one side by the slope or crown of the road.

F/asr Class
Section tn Cut

Ovt^n-Tfitrr^or

Fig.

/7«ar CtA»s

Section in Fill

79. Cross sections of earth roads, as recommended by the Iowa
Highway Commission.

Where thorough drainage is needed, it may bfe advisable
to place a tile Une at each side of the road, but under ordi-
nary circumstances one line of tile ought to be suflScient. In
providing tile drainage, care should be taken to see that the
tile is of ample size to meet the requirements of the area to be

Digitized by

Google

ROADS 149

drained. Where the road is on a hillside, seepage water,
which often causes a wet road, may be intercepted by locat-
ing the tile line at the upper side.

Side Ditches. In the construction of earth roads, side
ditches are provided to receive the water and carry it along
the road until points are reached where it may be discharged
into natural channels. An even grade or slope should be
given, so that the water will not collect in puddles in the side
ditches. It is impossible to maintain a good road under
such conditions. These ditches should be of suflScient
capacity to care for the water. They should be so con-
structed as not to be dangerous to vehicles when driven into
them. The outside bank should not be so steep as to cause
the soil to cave into the ditch and partially stop the flow of
water. Side ditches should be easily constructed and cleaned
with the common road machines. It is desirable that they
be of such form as to permit the mowing of weeds in them with
a common mower. In some locaUties it is desirable that the
side ditches have a form that will hold snow during the winter
months, facilitating sled traffic. A good form for the side
ditch is the V shape, with the outside bank having a slope of
1 J^ to 1 and the inside bank with a slope of 3 to 1, as shown
in the accompanying cross-section of an earth road.

The Crown. It is highly important that the middle of
the earth road be higher than the sides, which will cause the
surface water to drain quickly to each side and not He on the
surface and soften it. This oval part of the road is usually
called the crown. The road should not only be oval, but
should also be smooth so that the water will not lie in pockets
on the surface. It is not so important that the crown be of a
particular form, except to secure uniformity of construction,
but it is important that it be smooth and that there shall be
some slope to each side. If the slope be too steep, the travel

Digitized by

Google

150 AGRICULTURAL ENGINEERING

will have a tendency to concentrate at the middle of the road,
which in a very short time causes ruts. A slope of J^ to
1 inch to the foot, as shown in the accompanying sketch, is
customary.

Road Maintenance. In order to keep the earth road in
the best possible condition, it is necessary that the oval
shape of the surface be maintained, and that ruts be pre-
vented from forming. To do this, the roads must receive

Fig. 80. An earth road maintained in good condition by the road drag.

practically constant attention. The best device for keeping
an earth road smooth is the road drag.

The Road Drag. The road drag is a device for smoothing
earth roads. It is sometimes called the King drag, as its
use has been urged by D. Ward King, of Maitland, Missouri.
Its construction will be described later. The drag is usually
drawn with the blades at an angle with the direction of travel^

Digitized by

Google

R0AD8 161

SO that the soil which is carried out by the mud that sticks
to the wheels may be replaced and the general wear repaired.
Width of Earth Roads. The right of way provided in
most states for public roads varies from 40 to 66 feet. This is,
perhaps, more land than is needed for that purpose, in most
instances. It is unusual to improve more than about 36
feet of this right of way, making each side ditch about 9 feet
wide and the crown proper 18 feet wide.

Fig. 81. A typical condition of an earth road on which the drag has
not been used.

Earth Road Grades. The grade of earth roads may be
greater than those of roads surfaced with stone or similar
material, because the loads which are hauled on level earth
roads are not as great as those usually hauled on hard roads,
owing to the fact that the rolling resistance due to the softer
road surface is greater. Thus the smaller loads adapted to
earth roads may be hauled up steeper grades with the same

Digitized by

Google

152 AGRICULTURAL ENGINEERING

increase of effort that larger loads require on lower grades.
It is of course desirable to keep the grade as low as possible,
but different locaUties have different standards for the maxi-
mum grade. This maximum varies from 10 per cent for
roads used but little, to 4 and 6 per cent for those on which
the traffic is heavy.

The drag can be used to the best advantage following
ra'ns, when the soil is still moist. It then has a better
smoothing action and the earth scraped into the low places
is easily compacted. Roads which are dragged continu-
ously for a term of years become very dense and hard.

QUESTIONS

1. What is the mileage of earth roads in the United States?

2. Why should earth roads be given careful attenti(Hi?

3. What are the two divisions of the subject of earth roads?

4. Why is the drainage of earth roads important?

5. How much slope should the crown of the road have toward the
side ditches?

6. Is it important that the crown be of any particular shape or
form?

7. What will be the result if the sides of the crown are given too
much slope?

8. How should earth roads be maintained?

9. What is a good width for a country earth road?

10. What should be the maximum grade for earth roads?

11. Explain the action of the road drag.

Digitized by

Google

CHAPTER XXV

SAND-CLAY AND GRAVEL ROADS

Clay Roads. By careful construction and continued care
an earth road may be made fairly satisfactory. This is true
where such a road is made of clay. The construction and
maintenance of a clay road consist primarily in providing
drainage. Such a road should be kept as dry as possible.
It should have sufficient slope from the center toward the
sides to insure quick surface drainage to the side ditches;
and, as far as practical, underdrainage should be provided to
carry oflf the water that comes up from below. At best, how-
ever, the clay road is not highly satisfactory. During the
wet weather it becomes soft, and owing to the stickiness of
the clay the surface is rapidly destroyed.

Sand Roads. In many localities the surface of the roads
is composed largely of sand. Sand roads present an entirely
different problem from clay roads; they are at their worst
when dry, and are best when moist. For this reason some
skilled highway engineers advise that sand roads be made
flat, or without a crown. Straw, sawdust, and other mate-
rials are added to the sand in order to hold the moisture,
causing the sand to remain as compact as possible. It is
also noticed that sand roads are best when shaded by trees.

Sand-Clay Roads. Where clay roads and sand roads
exist in the same locality, it has been observed that nearly
always there is a good piece of road between the stretch of
day road and the stretch of sand road. This would indicate
that a mixture of sand and clay makes a better road surface

153

Digitized by

Google

154 AGRICULTURAL ENGINEERING

than either one alone, and it has been demonstrated fully
that this is true. In constructing the sand-clay road, suflS-
cient clay is added to the sand, or sand to the clay, as the case
may be, to fill the open spaces between the sand particles
with clay, causing the mixture to form into a very dense and
impervious layer. Tests should be made to determine the
amount of clay which must be added to the sand, or the
amount of sand which must be added to the clay* The re-
quired material is hauled to the roads to be improved and the
mixture made by plowing, harrowing, and rolling. If after a
time it is noticed that the road surface balls up and sticks to
the wheels of the vehicles driven over it, there is not a suffi-
cient amount of sand in the mixture. On the other hand, if
during the dry weather the surface becomes loose, it would
indicate that more clay should be added. Sand-clay roads
are very cheap, often their cost does not exceed more than
$100 to $200 per mile and seldom exceeds $400 per mile.
The sand-clay road is simply a step toward the gravel road.

Gravel Roads. Gravel consists of particles of stone
which have been rounded by the action of water and ice,
and which are deposited in banks. Gravel of the right kind
is a material from which a very satisfactory road may be
constructed. It is not suited, however, to heavy traffic.
It is suited to average country conditions, and in many
localities where gravel can be had conveniently it is the most
desirable material to use.

Durability of Gravel. Gravel that is satisfactory for the
siu'facing of roads should be durable and not so soft as to be
ground into dust by much traffic, neither should it be so
brittle as to be easily shattered or broken. As a general
rule, most gravel may be depended upon to be fairly durable,
for if it were not so it would not exist as gravel after having

Digitized by

Google

ROADS 155

undergone the test placed upon it in its formation and trans-
portation by water and ice.

Size of Gravel. It is desirable that the pebbles in the
gravel for road surfacing be not too large. It is customary
to screen out all pebbles or stones larger than ^ to 1 inch in
diameter. In some cases where larger pebbles exist they
are screened out and used for the first courses in the con-
struction of the road bed. If large pebbles or stones are
left in the gravel they are quite apt to come to the surface
through the action of the traffic and of frost. Gravel
should also vary in size, so that there will be small pebbles
to fill the open spaces between the larger ones, and in
turn the space between the smaller pebbles should be filled
with sand grains. When^the gravel varies in size in this
manner a very dense mixture is obtained, which is ideal for
road material. In some cases where the different sized
pebbles do not exist naturally in the proper proportion to
make a dense mixture, it may be profitable to screen the
gravel and remix it more nearly as it should be.

The Binder. In order that the gravel shall form a
satisfactory surfacing material for a road, it must contain or
be mixed with some material which will hold the pebbles
together. In most instances this binding material is clay.
Clay exists to some extent in all gravels. When the gravel
will stand vertically in the bank, and when it resists the
action of frost and must be loosened with a pick, it is quite
likely to contain the proper amount of binding material. If
a sufficient amount of clay is not present to fill the open
spaces between the pebbles and cause them to be packed
into a dense structure, additional clay should be added.
Clay has several characteristics which recommend it as a
binding material. It is cheap, can be easily reduced to a
finely divided state, and is usually found to a more or less

Digitized by

Google

156 AGRICULTURAL ENGINEERING

extent in the gravel. On the other hand, it has some
undesirable characteristics. It loses its binding power when
dry, and is susceptible to the action of frost. In many cases
other kinds of binders are used. Stone dust has excellent
cementing properties and is considered better than clay,
but is more expensive. As will be explained in the chapter
on stone roads, automobiles have introduced many new
problems in connection with road construction. Many
forms of binders and dust preventives are being experi-
mented with. Bitumen, tar, crude oils, and chlorides are
used to hold the gravel together.

Drainage. A good gravel road must be thoroughly
underdrained if it is to be satisfactory. The method of
draining does not differ materially from that described for
earth roads. Many mistakes have been made by those

^*€*ion tn Cut

FiflT. 82. Cross section of gravel road. (Iowa Highway Commission.)

having the matter of road construction in hand, by applying
surfacing material to a road which needed underdrainage
badly, and so the material did not produce the results which
were hoped for. The ground water coming up from below
softened the surface, and the gravel was forced down into
the earth until it entirely disappeared. Gravel roads should
have suJBScient amount of crown or lateral slope to secure the
rapid drainage of all surface water to the side ditches. The
amount of slope is usually given as J/^ to 1 inch to one foot of
width.

Surface Construction. There are two general methods of
surfacing roads with gravel. The cheapest method is known

Digitized by

Google

ROADS 157

as surface construction. In this method the gravel is hauled
and dumped on the prepared road bed, which usually is an
earth road, and the packing is left to the traffic. Sometimes
little attention is given to the matter of smoothing and
spreading the gravel.

The thickness of surface gravel applied in this manner
varies from 3 to 6 inches at the center, usually tapering down
to a less thickness at the sides. It is considered the best
practice to apply the gravel in two layers; thus if the total
thickness of six inches of gravel is to be appUed, it will be
spread in two layers
three inches each. After
the first has been spread,
sufficient time should be
allowed for the traffic
to pack it quite thor-
oughly before the second
layer is spread.

Trench Method. In
the trench method the
road surface is carefully
graded and rolled to re-
ceive the gravel. Usually

banks are provided at mg. SS. Model of a gravel road Illus-
., .1 u' u 'ii u u tratingr the trench method of construction.

tne side WniCn WIU nOla a shows prepared sub-grrade; B, first course
.V 1 i.u J ot gravel; C, upper course of gravel. (Bui.

tne gravel on tne roaa ae, omce of pubiic Roads, u. s. Dept. of
proper. In trench con- ^^^'^

struction the gravel is usually placed in two or more layers,
the first being composed of coarse pebbles, and is thor-
oughly rolled with a heavy roller before the other courses
are appUed. This form of construction gives a finished
road at once, and for this reason is more desirable than the
surface method. This is much more expensive, however.

Digitized by

Google

158 AGRICULTURAL ENGINEERING

Cost of Gravel Roads. The cost of gravel roads varies
widely, depending largely upon the availability of gravel.
The method of construction is another important factor.
The amount of gravel used varies widely with different con-
struction. In some cases as little as 1-10 of a yard of gravel
may be appUed per foot of length. In other cases a cubic
yard may be applied per foot.

Roads may be graveled Ughtly by the surface method at
a cost of from $200 to $500 per mile. Where the roads are
constructed by the trench method, the cost usually varies
from $1000 to $2000, but it may run as high as $3000 per
mile.

Maintenance of Gravel Roads. Gravel roads should be
kept smooth and oval by the use of the road drag. The road
drag is not needed as often on gravel as on earth roads, yet
pockets and ruts should not be allowed to form. From time
to time additional gravel should be added to the surface.

When repairing gravel roads in this manner, it is
customary to apply about two inches of gravel at a time,
except at the places where the road has been destroyed, in
which case it will be necessary to use more gravel. The
length of time in which the gravel road may go without an
application of additional material varies so much with the
traffic, grade of materials used, and other conditions, that
no attempt will be made to suggest an average period.

QUESTIONS

1. Under what conditions is the clay road at its best?

2. How is a sand road improved?

3. What principle is involved in the construction of the sand-clay
road?

4. How much does a sand-clay road cost?

5. To what conditions is the gravel road adapted?

6. What are the requisites of good road gravel?

Digitized by

Google

ROADS 159

7. Why should road gravel vary m size?

8. Why is it best not to use too large pebbles?

9. What is common binding material?

10. How much binder should be used?

11. Why should a gravel road be thoroughly underdrained?

12. Describe the surface method of constructing gravel roads.

13. What thickness of gravel is usually applied?

14. Describe the trench method of constructing gravel roads.
16. How much do gravel roads cost?

16. How are gravel roads maintained?

Digitized by

Google

CHAPTER XXVI
STONE ROADS

Stone roads include all roads on which broken stone is
used as the principal surfacing material. Stone has been
used in road construction from very early times, where
first-class roads were desired.

Telford Roads. Some broken stone roads are given the
name of Telford, when they incorporate some features of
road construction which were used by Mr. Thomas Telford,
a famous English engineer. The distinguishing feature of
the old Telford road was that the lower course or layer of
stone was made of rather large flat stones laid in place by
hand. At the present time any road which uses large pieces
of material in the base or lower layer may be called a Tel-
ford road.

Macadam Road. Most stone roads which have been
built in recent years follow the form of construction proposed
by John Loudon McAdam, another famous EngUsh road
engineer, who Uved between 1756 and 1836. So general is
the use of this construction that it has become customary to
call all broken-stone roads macadam roads.

Macadam roads are made of broken stone throughout.
The stone is applied in three or more layers, and in the usual
construction it is customary to place the larger fragments in
the lower course.

Road Stone. Not all kinds of stone can be used success-
fully in the construction of stone roads. Good road stone
must be hard so that it will not be crushed by the traffic
which will come upon it. It must also be hard enough to

IGO

Digitized by

Google

ROADS 161

resist wear, which requires somewhat different character-
istics from the abiUty to withstand pressure. Road stone
should also be tough, in order that it will not be shattered
by the blows to which it will be subjected. It must also, in
the usual macadam construction, furnish a dust which has
a cementing or binding power. As the stone wears, a dust
forms, which becomes lodged between the stone particles.
This dust when wet forms a sort of cement which, upon
hardening, holds the fragments of stone together, resembling
in many respects cement or concrete.

Testing Stone for Road Construction. Nearly every
state maintains a highway commission which is equipped with
apparatus for testing road stone for the various qualities
mentioned. These tests are capable of determining fairly
and accurately just what may be expected as to durability
of a certain kind of stone when used in road construction.
The construction of stone roads is so expensive that in no
case should materials of doubtful value be used.

Fig. 84. Rolling the first course of stone.
6—

Digitized byVjOOQlC

162 AGRICULTURAL ENGINEERING

The Canstruction of Stone Roads. As usually con-
structed, the stone surfacing in a country road is made from
12 to 15 feet wide. The stone proper is usually applied in
two layers, on top of which a third layer of stone dust or
other bmding material is used. The lower course isusually
made from 2>^ to 4 inches thick, and the upper courses
from 1)^ to 2 inches thick. Thus the total thickness of the
stone varies from 4 inches to 6 inches at the center of the

road, and from 2}^ inches
to 4 inches at the outer
edge. It is customary
tc apply more material
in the center of the road,
where the wear from
traffic is the greatest,
than at the outside.

If automatic dump
wagons are not used to
spread the stone, it is
generally recommended
that it be applied with

Pig. 85. Model of a water-bound macad- shovels. WhcU StOUC is
am road. A represents the prepared sub- J,,^^^^ ;■„ hpans the
grade. B represents the first course of QUmpea m ueaps, tiic

Xfe TsZne.ina%''?^TLi'^i^^^^^^^ larger fragments roll to
J^X'^^Ro^'dtxJ.'aTept.'TAlr^^ '' the outsidc of the pile

and the finer portion is
left in the centor. The stone should be applied in layers of
uniform thickness, making proper allowance for the shrink-
age due to rolling. The packing is done with a steam roller.
Horse rollers are not made heavy enough for this purpose;
the ten-ton traction roller is the siz^e in general use. It is
customary to begin the rolling at the outside and work
toward the centor. Aftor the lower course is thoroughly

Digitized by

Google

ROADS 163

packed over the entire width of the road, the upper courses
may be applied. This consists of fragments of stone which
vary in diameter from IJ^ to 1}/^ inches. After being
spread in a manner similar to that described for the lower
course, the layer of binding material, which usually con-
sists of stone screenings and dust, is applied. This is usually
about 1 inch in thickness and it is washed down into the
crevices between the stone as much as possible by sprinkling.
Rolling is continued until the water that is applied in
sprinkling remains on the surface. No more binding
material should be used than is necessary, and care should
be used to leave the surface of the road as smooth and in as
perfect condition as possible. After rolling and bringing
the surface into proper condition, the embankments at the
sides should be thoroughly rolled smooth so that there will
not be any unevenness existing between the stone and the
side ditches.

Bituminous Macadam Roads. The construction which
has just been described has been the standard method of
stone road construction for many years, but owing to a
change oi traffic other forms of construction have come
into use, and this construction is sometimes designated as
"water-bound macadam roads." It has proved to be
highly satisfactory for the main traveled country road,
where first-class roads are desired and where the traffic
is Umited to horse-drawn vehicles. The automobile, how-
ever, has intrqduced a new problem in connection with road
construction. The automobile traveling at a high speed
with its broad pneumatic tire sucks out from between the
stone fragments the dust which forms the binding material,
and causes the stone to loosen, or "ravel," as it is some*
times described. So extensive has the motor traffic become
in certain localities, that not only must steps be taken to

Digitized by

Google

164 AGRICULTURAL ENGINEERING

protect the macadam roads which are now in use, but
another form of construction must be adopted for new
roads. At the present time a rather large niunber of mate-
rials are being used as binders experimentally. One class
of these binders is known as bitiunen, which includes
not only the natural asphalt products but also similar
material obtained from gas plants in the nature of tars.
In addition to bitumen, various grades of oils are sometimes
used to protect roads. Some of these are known as dust
preventives.

Method of Constructing Bituminous Macadam Roads.
There are two genel*al methods of constructing bituminous

macadam roads. One is
known as the penetration
method, and the other
the mixing method. In
the penetration method,
the foimdation or sub-
grade is prepared sub-
stantially as for the
water-bound macadam
road, and the first or
second layer of stone
also applied in the same
way. On the second.

Fig. 86. Model of a bituminous macadam ^^ „^^^^ ^^,,,.«^ ^« 1»,r^M

road made by the penetration method. A OT Uppcr, COlU^e Or layer,

represents the prepared sub-grade. B rep- v.;+^i»v^rx-r* ia *%T\r\}\o.A o-f

resents the first course of stone, and C the DlXUmen IS appiiea u,\}

second course. D shows the first applica- ,.« *^„„ «Q+.aa o^Tt^r^amr^tr

tion of bitumin. E shows the application various ratcs, averaging

of a course of stone chips. F shows sec- -^-,«u«*>« 1 1/ n>o11r\y>ci r^^i.

ond application of bitumen. G shows the pcrhapS 1>^ gallOUS per

completed road with a layer of clean stone «p,„o«^ varH FnllfiwiTio'

chips, lightly rolled. (Bui. 36, Office of SquarO yarU. TOUOWing

Public Roads. U. S. Dept. of Agr.) ^J^jg ^ J^^y^^ ^f ^^^^^

chips is applied, and then another layer of bitumen at the
rate of perhaps }4 gallon per square yard.

Digitized by

Google

ROADS 165

In the mixing method, the second crust or layer of stone
is mixed or covered with bitumen before spreading. This is
also true of the upper layer of sand or chips, which is thor-
oughly mixed with bitumen before applying to the surface.
It is expected that roads of this type will largely replace the
standard or water-bound type.

Cost of Stone Roads. The cost of stone roads will vary
largely with the cost of materials; this in turn being directly
dependent upon their availability. The cost in different
parts of the United States varies from $1.20 to $1.50 per
square yard, and from $4000 to $10,000 per mile.

Maintenance. Macadam roads must be given constant
attention or they will be rapidly destroyed. All ruts should
be quickly filled with new material and not be allowed to
become larger. After several years of wear, depending
upon the durability of the materials used, it will be neces-
sary to apply a new layer of materials. This is usually
accomplished by loosening or scarifying the surface, leveling
or rolling it until thoroughly compact, and then applying new
material in a layer two or three inches thick, depending upon
the condition of the road. This repair layer is applied in a
way similar to the laying of the second course in the original
construction.

Brick Roads. In some localities where stone is very
expensive or where good durable brick may be obtained
cheaply, brick roads will be found to be the most practical.
In the construction of a brick road, the subgrade or foun-
dation is carefully prepared by grading and rolling, and the
sides of the road are provided with concrete or wooden
curbs, to hold the brick in place. On the subgrade a course
of stone is laid and thoroughly rolled, or a coarse layer of
concrete is spread, usually about 6 inches deep. On this
course a layer of sand is spread and smoothed as a cushion

Digitized by

Google

166 AGRICULTURAL ENGINEERING

on which the brick is laid. In order to allow for the expan-
sion and contraction due to changes of temperature, an
expansion joint must be left occasionally.

Concrete Roads. Owing to a reduction in th^ cost of
Portland cement, concrete is now used to a limited extent
in the construction of roads. One objection to concrete
roads is that they are slippery, but this may be overcome.
The construction of concrete roads has not as yet become
standardized.

QUESTIONS

1. What is a stone road?

2. Describe the Telford fonn of constructioD for stone roads.

3. Describe the construction of the macadam road.

4. What are the requisites of stone for road construction?

5. Why should road stone be tested?

6. Describe the construction of water-bound stone roads.

7. How much should a stone road be rolled at the finish?

8. Describe two methods of constructing bituminous macadam
roads.

9. How much do macadam roads cost per mile?

10. How should macadam roads be maintained?

11. Where may brick roads be constructed advantageously?

12. Describe the construction of brick roads.

13. What is one objection to the concrete road?

Digitized by

Google

CHAPTER XXVII
ROAD MACHINERY

Classes of Road Machinery. Road machinery may be
divided into two general classes, those used in building roads
and those for the maintaining of roads. Although machines
in the first class may be used in connection with the repairing
of roads, there are a few machines which are used solely for
this purpose. There is a rather wide variety of road
machines, and it is not possible in this chapter to describe
even briefly all of the machines which might be considered.
SCRAPERS, ROLLERS, ETC.

Scoop Scrapers. One of the most simple machines used
in connection with road construction is the scoop scraper, or
"slip." This scraper is simply
a large scoop arranged with a
bail for drawing and handles for
dumping. The size is usually
indicated by the number of
cubic feet of earth the scraper

will hold, which varies from 3 p,^~'^,p 3,raper or Slip.

to 7. The cost of a scoop

scraper varies from 6 to 10 dollars. The scoop scraper is

used for moving earth short distances.

Pole or Tongue Scraper.
The pole or tongue scraper is
used in leveUng the road sur-
face. The size is indicated by
the width in inches, and the
pi». 88. Tongue scraper. cost vaHcs f rom 6 to 7 doUars.

167

Digitized by

Google

Fig. 89. Buck scraper.

168 AGRICULTURAL ENGINEERING

Buck Scraper. The buck scraper is sometimes called
the Fresno, and is used extensively in irrigated re^ons in
preparing land for irrigation. It is capable of being adjusted
to spread the earth in a layer of almost any thickness when

dumped. These scrapers are
made 3H> 4, and 5 feet wide,
and have capacities of 8, 10,
and 12 cubic feet, respec-
tively.

The Wheel Scraper. The
wheel scraper consists of a
steel scoop on wheels and equipped with levers for raising
and lowering and for dumping. It is used where the earth is
to be moved some distance,
100 feet or more. The size of
this scraper is usually desig-
nated by numbers 1, 2, and
3, which have the capacities
of 9, 12, and 16 cubic feet,
respectively. There are sev-
eral grades of construction
to be obtained. If the haul,
or distance the earth is to be
moved, is great, the larger

- , - - - ,- Fig. 90. Wheel scraper, dumped.

Size should be used, even if

an extra team or ''snap'' be required to help load the scraper.
The Scraping Grader. The scraping grader is the princi-
pal machine used in the construction of earth roads. It con-
sists usually of a four-wheeled truck, with a wide steel blade
mounted underneath, which may be adjusted to almost any
angle. The standard machine requires four or more horses
to operate it successfully in average soil. A Ughter or
special machine is made which can be used for repair work.

Digitized by

Google

ROADS 169

and is often used with two or four horses. In addition to the
machines with four-wheeled trucks, there are quite a number
of machines on the market in which attempts are made to
simplify the construction, and also to reduce the cost. The
standard scraping grader costs from $200 to $250 at the
factory. In addition to the usual adjustments provided
for setting the cutting blade to any angle with the direction
of travel, for raising and lowering either end and giving it

Fig. 91. A scraping grader and a horse roller at work.

any desired inclination forward or backward, the wheels
of the machine are made to follow in the furrows of the blade,
or may be adjusted at such an angle as to resist the side
thrust due to using the blade at an angle with the direction
of travel. The use of the scraping grader is quite simple,
but much skill may be obtained by experience. In using a
machine it is customary to plow a furrow at the side of the

Digitized by

Google

170 AGRICULTURAL ENGINEERING

road where the side ditch is to be located, using one comer
of the blade. The earth from this furrow is then scraped to
the center of the road and spread by the grader.

Elevating Graders. The elevating grader is a compli-
cated machine in many respects. It is provided with a four-
wheel carriage and a plow that is operated at one side. An
endless apron driven by power from the rear truck-wheels
receives the earth from the plow and elevates and discharges
it either in the center of the road or into wagons drawn
beside the grader. These machines may be operated either
by horses or by traction engines. The standard machine
requires 12 horses, eight in front and four behind. This

Fig. 92. An elevating grader.

machine will grade a new earth road in good soil at the rate
of a quarter of a mile per day, where the width does not
exceed thirty feet and where a crown of twelve inches at
the center is made. Elevating graders vary somewhat in
size and weight.

Horse Rollers. Horse rollers for road construction con-
sist essentially of a large cast-iron drum with a frame and
tongue for drawing. They are usually made 4 to 6 feet wide

Digitized by

Google

ROADS 171

and weigh from 3 to 6 tons. To overcome the difficulty of
tmning the rolbr about, a tongue with a wheel truck is
attached to a yoke which is pivoted directly over the center
of the roller drum, and which may be unlatched from one
side and turned about to the opposite side and latched,
enabUng the drum to be drawn in the reverse direction with-
out turning. Boilers made of cast-iron cost about $100 per
ton of weight. Cheaper rollers are made by building up
the hollow drum of cast iron or steel plate, and filling with
water or concrete. In the construction of stone roads it is
highly essential that a heavy roller be used, and for this
reason the horse roller is seldom used.

Power Rollers. The steam roller is of two types — one
known as the three-wheel roller and the other as the tandem
• roller. The three-wheel roller resembles the traction engine,
in which the guide wheels are replaced with a rolling drum
and the drivewheels have smooth treads. Gasoline and oil
engines are being substituted for steam power for rollers
to some extent. Many traction engines are made so as to be
easily equipped in this way. The weight of these rollers
varies from 10 to 20 tons and the pressure under the drivers
will vary from 450 to 650 pounds per inch of width.

Tandem rollersi sometimes called asphalt rollers, con-
sist of two rolling drums at the ends of a frame. Most of the
weight is applied to one of these drums, which is driven by
power from a steam or a gasoUne engine, and the other is
used for guiding. This type of roUer tends to leave the sur-
face smoother than the three-wheel type, but cannot be
handled quite as conveniently over country roads. Although
it can be used for drawing other machines it is not used so
extensively in this connection as the three-wheel type. It
cannot be provided with spikes for loosening old road sur-
faces preparatory to resurfacing.

Digitized by

Google

172 AGRICULTURAL ENGINEERING

Rock Crushers. One of the essential machines in con-
nection with the building of a stone road is the rock crusher
for reducing stones to fragments of the proper size. Usually
these crushers are located at the quarry, and the stone is
shipped ready for application to the road.

Pig. 93. Stone crushing plant. A three-wheeled steam roller and a
dump wagon are shown in the foreground.

Oflier Machinery. The equipment necessary for build-
ing stone roads includes several other machines. Among
these may be mentioned screens for grading the stone, dump
wagons for hauling and spreading the stone, and sprinklers
for applying water or binding material in the form of a
liquid. When old roads are to be repaired, plows or scari-
fiers, which are heavy tools with cultivator-shaped teeth for
breaking up the surface, are necessary.

Digitized by

Google

ROADS 173

MACHINES FOR MAINTAINING ROADS

Road Drags. The principal machine for maintaining
roads of all kinds is the road drag. As devised by Mr. D.
Ward King this consists of two planks or halves of a split
log, about 8 feet long, and held about 30 inches apart with
braces. These planks are so placed that one will follow
the other when drawn at an angle of 45 degrees with the
direction of travel. The front plank is usually shod with a
steel blade for about one-half its length, which resists the

Fig. 94. Road drags made of plank and split log.

wear and enables the drag to have more efifect upon the sur-
face. Two chains are provided, one from each end of the
drag, which are of such length as to give the drag the desired
inclination with the direction of travel.

It has been found that the drag works best with the longer
chain passed over the plank, and the shorter chain attached
near the middle of the short plank close to one end. There
are many other types of drag to be found in use. One is
known as the V drag, which is designed to cover the entire
width of the road surface at a time. There are also several
types of road drags made of angles or bars of steel in place of
the planks of the King drag.

Digitized by

Google

174 AGRICULTURAL ENGINEERING

QUESTIONS

1. For what may the scoop scraper, or slip, be used?

2. What are the special uses of the tongue and buck scrapers?

3. Describe the construction of the wheel scrapers.

4. Why is it economical to use large sizes where the haul is long?

5. Describe the work of the scraping grader.

6. Describe the construction of the devating grader.

7. What is the usual weight of horse rollers?

8. Describe two types of steam rollers.

9. What are some of the machines required for the building of
stone roads not mentioned above?

10. Describe the construction of a road drag of plank or split logs.

Digitized by

Google

CHAPTER XXVIII
CULVERTS AND BRIDGES

Importance of Culverts and Bridges. A large proportion
of the cost of maintaining the highways of the country is
used in the construction of culverts and bridges. Not only
is it desirable that the money thus expended be used in such
a way as to secure the best results, but faulty construction
should be guarded against on account of the risk of life to
those who must pass over them with heavy loads. To
secure economy it is necessary that bridges and culverts i)e
intelligently and economically designed, and that they be
made of durable and permanent material. Recent changes
in road traflSc demand that there shall be advancement in
the designing and constructing of culverts and bridges, in
order that the heavier loads which bridges are now called
upon to bear shall be carried without risk of failure.

Design of Culverts and Bridges. The designing of cul-
verts and bridges should be placed in the hands of a skilled
engineer, who will be able to proportion the structure
properly. The practice in certain localities of making appro-
priations of public funds for bridges without first securing
from one who has had experience an estimate of the cost of a
bridge to fill the requirements of the conditions to be met
may be justly criticised.

Size. The first feature in the consideration of a culvert
is the determination of the size required. Highway engineers
have reported that culverts are often not properly propor^
tioned to the needs to be met, being either too large or too
small. The area of a cross-section of a culvert or bridge

173

Digitized by

Google

176 AGRICULTURAL ENGINEERING

should vary with the amount of water which must pass
through it. Some engineers use Kutter^s formula, given
in the chapter on land drainage. To determine the required
area of the cross-section of a culvert, a more simple formula

Fig. 95. Making a concrete culvert.

has been proposed by Professor A. N. Talbot, of the Uni-
versity of Illinois. Professor Talbot states that the formula
is to be used as a guide to judgment. It is stated as follows:

Digitized by

Google

ROADS

177

The area of waterway in square feet should equal

C X

(drainage area in acres)'

in which C is a coefficient and will vary from K to 1, the larger
value being used where the slopes are steep and the ground is
broken. The 4th root of the quantity under the radical may
be obtained by extracting the square root of the square root.

Foundation. Many bridges fall because they are not
placed upon a proper foundation. Great care should be used
to see that solid earth which will not be undermined by water
is available for the smaller bridges. For larger bridges the
foundation should be placed on solid rock, if possible; and
where this can not be done, piling and other methods of
providing large surface for the foundation should be used.

Concrete Culverts and Bridges. Perhaps there is no
purpose to which concrete made of Portland cement can be
put to better use than in the construction of culverts and

Q£ lhrOOC£D COMCQCTC

Fig. 96. Plans and table of materials for reinforced concrete culvert.

Digitized by

Google

178 AGRICULTURAL ENGINEERING

bridges. Stone and brick make desirable culverts, but the
convenience of handling and reinforcing concrete with steel
makes it very useful for culvert and bridge construction.
Vitrified Pipe and Steel Pipe Culverts. Vitrified clay
pipes or sewer pipes are used extensively for small culverts,
and are quite satisfactory when covered with a sufl&cient

amount of earth. It
is desirable, however,
that the ends be pro-
tected with wing walls
made of masonry.
Steel or iron pipes are
used to a considerable
extent; but owing to
the thinness of the
metal in most cases,
they are regarded as
of questionable merit.
Cast-iron pipes are
regarded as quite
satisfactory, but are
expensive.

Fig. 97. Concrete culvert after the plan of *"® Work 01 State

^*«^ »«• Highway Commis-

sions. The majority of states now have a highway com-
mission or a highway engineer, whose function is to furnish
standard plans and specifications for culverts and bridges. It
is advised that these plans and specifications should be used
in all cases. Besides representing the most improved design,
they enable the work to be let by contract in a highly satis-
factory way. All features of the construction will be clearly
defined as to quantity and quality in the plans and specifi-
cations furnished by these officers.

Digitized by

Google

ROADS 179.

Large Bridges. All large bridges should be designed and
their construction supervised by a skilled engineer. In the

Fig. 98. A concrete bridge whicli failed on account of the foundation.

majority of states the state highway commission is in a posi-
tion to furnish such an engineer.

QUESTIONS

1. Why should culvert and bridge construction receive careful
consideration?

2. What should be considered in selecting a culvert or bridge?

3. What should govern the size of the culvert?

4. Why is it important to have good bridge foundations?

5. Why is concrete a good material for culverts and bridges?

6. What are the merits of metal culverts?

7. What is the work of the State Highway Commission?

REFERENCE TEXTS

Roads and Pavements, by I. O. Baker.

Highway Construction, by Austin T. Bjrme.

A Text-book on Roads and Pavements, by Frederick P. Spaulding.

Bulletins of the Office of Public Roads, U. S. Depart, of Agric.

Digitized by

Google

PART FIVE— FARM MACHINERY

CHAPTER XXIX
FARM MACHINERY AND AGRICULTURE

Introduction of Farm Machineiy. Farming, or the culti-
vation of the soil to obtain a sustenance, was a recognized
occupation even before the time history was first written.
For ages, however, there was little development in farm
machinery. Until the beginning of the last century nearly
all the work of the farm was performed by the aid of crude
hand tools. The number of horse- or animal-drawn imple-
ments or machines that had been developed were few.

Although hand tools were used almost exclusively for
thousands of years, when the application of power other than
man power to the work of the farm began, the development of
machinery was very rapid. In the Twelfth Census Report it
is stated, "The year 1850 practically marks the close of the
period in which the only farm implements and machinery
other than the wagon, cart, and the cotton gin, were those
which, for want of better designation, might be called imple-
ments of hand production." In the early part of the nine-
teenth century the grain was cut with the sickle or cradle
and bound by hand. It was threshed by beating with the
flail or by the treading of animals. The plow was a crude
affair, usually homemade and shod with iron by the village
blacksmith, and the principal tool for cultivation was the
hoe. A cast-iron plow was first made by Charles Newbold,
of New Jersey, sometime between 1790 and 1796, and John

180

Digitized by

Google

FARM MACHINERY 181

Deere made his first steel plow in 1833. Patents on the
reaper were granted to Obed Hussey in 1833 and to Cyrus
W. McCormick in 1834. The two-horse cultivator was first
used about 1861. The first patent on a drill granted to an
American was in 1799, but the force feed for a drill was not
patented imtil 1851. The first patent on a com planter
came in 1839.

These machines did not come into general use until many
years after the date of the first patents. The old men of
to-day can remember the hand methods which prevailed
throughout the country during their boyhood and yoimg
manhood. The opening of large areas of rich agricultiu'al
land to settlement in the United
States during the middle of the
century, followed by the scarcity
of workers caused by the Civil
War, were no doubt the im-
portant influences in bringing „. «„ „^ . , , ^ ^

'^ . , . 1 . ^ ^^^- ^^' ^^® sickle and the

about a rapid mtrOdUCtlOn of cradle, hand tools for harvest-
farm machinery.

The influence of the introduction of farm machinery on
agriculture has been stupendous and far-reaching. Some of
the direct effects produced will now be set forth.

Change in Farm Labor. When hand methods prevailed,
the labor of the farm was performed largely by slaves or the
cheapest form of labor. From the beginning, the cultiva-
tion of the soil has been synonomous with deadening toil
and drudgery. The introduction of farm machinery has
changed this entirely, a fact which is emphasized by the com-
parison of the harvesting of grain with a modem self-binding
harvester with the old method of cutting with the sickle or
cradle and binding by hand; or the threshing of grain with
a modem threshing machine equipped with self-feeder,

Digitized by

Google

182 AGRICULTURAL ENGINEERING

weigher, and wind stacker compared with the threshing of
grain with a flail.

A poet once wrote of the agricultural laborer as the ''man
with the hoe, stolid and stmmed — a brother to the ox."
Contrast this condition with that of the operator of a modem
machine Uke a gang plow, a harvester, or a two-row culti-
vator, where no effort is required beyond the direction of the
energy of the horses and the adjusting of the machine.
J. R. Dodge, in the Report of the Industrial Conmiission,
1901, wrote, "As to the influence of machinery on farm
labor, all intelligent expert observation declares it benefi-
cial. It has relieved the laborer of much drudgery; made his
work easier and his hours of service shorter; stimulated his
mental faculties; given an equiUbrimn of effort to mind and
body ;. and made the laborer a more efficient worker, a broader
man, and a better citizen." It is doubtful if ^arming would
appeal at all to the young men of to-day if there had not been
a change from hand methods to machine methods.

Length of Working Day. The working day has been
materially shortened since the introduction of labor-saving
machinery. The capacity of the worker was so limited with
hand methods that it was necessary to work to the limit of
endurance when crops demanded it.

Increase in Wages. There has been a very marked
increase in wages with the introduction of farm machinery;
and although this is true of all occupations, farm machinery
has undoubtedly been a factor in bringing about the increase.
A farm worker can earn more by working with a machine
than by hand; however, a complicated machine requires
greater skill for its successful operation. It was thought
by many at the time machinery was being generally intro-
duced that wages would be decreased, owing to the fact that
some workers would be displaced with machines. In the

Digitized by

Google

FARM MACHINERY 183

United States, in 1849, the average wages of a farm worker
did not exceed $120 a year. In countries where machinery
is used little at the present time, wages are very low.

Labor of Women in Fields. When hand methods pre-
vailed, the labor of women was required in the fields to care,
for the crops during the seasons when they required urgent
attention. Now the services of women are seldom required
in the field, and in addition many machines have been
devised to aid her in the housework. Again, much of the
work formerly required of her in the home, like spinning^
weaving, garment making, soap making, and candle making
have been transferred to the factory, where machinery may
be economically used in the work.

Percentage of Population on Farms. The percentage of
the total population Uving on farms in the United States has
decreased continually since 1800. At that time 97 per cent
of the people Uved on farms; in 1849 the percentage had
decreased to 90 per cent, and in 1899 only 35.7 per cent of the
people lived on farms.

Increase in Production. Notwithstanding the decrease
in the farm population in this country, the production of
agricultural products per capita has increased. In 1800,
5.50 bushels of wheat were produced per capita; in 1849,
4.43 bushels; in 1880, 9.16 bushels; in 1890, 7.48 bushels;
and in 1900, 8.66 bushels per capita. The production of
com per capita increased from 25.53 bushels in 1850 to 34.94
bushels in 1900.

Cost of Production. The cost of producing farm crops
has been materially lowered, although the cost of labor has
increased many fold. It is stated by one authority that the
average cost of producing farm crops was reduced 50 per
cent from 1850 to 1895. This reduction of cost is largely
due to a reduction in the time required in production. In

Digitized by

Google

184 AGRICULTURAL ENGINEERING

the thirteenth annual report of the Department of Labor it
is stated that the amount of labor required to produce a
bushel of wheat by hand methods was 3 hours and 3 minutes,
and by machine methods this has been reduced to ten min-
utes. In the 1899 Yearbook of the Department of Agricul-
ture it is reported that the average time of labor required to
cut and cure a ton of hay has been reduced from 11 hours to
1 hour and 39 minutes.

Quality of Products. The quahty of farm products has
been materially influenced by the introduction of farm
machinery which enables the farmer to harvest his crop at
the best time. For instance, when hand methods prevailed
it was customary to begin the harvesting of small grain
before it was properly ripened, and the harvesting was con-
tinued past the time the grain was in the best condition,
resulting in shrunken and damaged grain. The crops are
generally cleaner and more uniform now than imder the
methods prevailing three quarters of a centmy ago. It
would be difficult now to induce people to eat bread made
from wheat threshed by the treading of animals.

Income of Farm Workers. A study of the Census
report of the income of farm workers in the different states
and the average investment in farm machinery indicates
that the income varies almost directly with the amount of
machinery. 1 The following table contains only the extreme
cases given in the report.

G. F. Warren and K. C. Livermore, of Cornell University,
in reporting an agricultural siirvey made in Tompkins
County, New York State, say, "In each of the groups [refer-
ring to size of farms] the farmer's labor income is almost the
same as the value of his machinery." These observations

i S. A. Knapp, of the United States Department of Agriculture, has reported
this data from the census report, in Circular 21, Bureau of Plant Industry.

Digitized by

Google

FARM MACHINERY

185

Influence of farm machinery on income.

State

Annual income of each
worker

Value of ma-
chinery and im-
plements for
each farm

Florida

$119.72
143.98
611.11
755.62

$ 30.43

23.40

Iowa

196.55

North Dakota

238.84

are sufficient to indicate clearly that farm machinery is an
important factor in modem farming operations and that an
agricultural student who intends to make the farm the object
of his Ufe work will do well to give a careful study of the
subject of machinery.

QUESTIONS

1. Explain some of the causes which brought about a rapid de-
velopment of agricultural machinery in America.

2. What were the hand tools used in harvesting and cultivation?

3. What effect has the use of machinery had on farm labor?

4. Has the length of the working day changed since the introduc-
tion of farm machinery? Explain.

5. How have wages changed since the time of hand production?

6. Show how machinery has changed the work of women.

7. Explain how production of some of the principal crops per capita
in the United States has changed, and also explain the changes in the
percentage of the population living on farms.

8. How has the cost of production changed with the introduction
of machinery?

9. What effect has machinery upon the quality of products?

10. What is the ratio between the amount invested in farm ma-
chinery in the various states and the average income of the farm
workers?

Note: The student should study the development of farm
machinery by consulting the older residents in the community in regard
to the methods in vogue during their lifetime. A study should also
be made of the cost of doing work by di^erent existing methods.

Digitized by

Google

CHAPTER XXX

DEFmrrioNS and principles

A Tool. A tool is an instrument such as a hammer, fork,
or spade used in performing manual operations. Tools so
defined will not be discussed in this text. The term may be
used, perhaps incorrectly, to designate a machine or an imple-
ment. Machines for making hay, for instance, are some-
times called hay tools.

Implements. The term implement is applied to both
tools and machines. A dealer in these wares is generally
known as an implement dealer.

Machines. A machine is any device consisting of two
or more parts arranged to modify forces and motions, to
produce a desired effect or do some useful work. Machines
require energy from an outside source to drive or operate
them, and of this energy a part is required to drive the
machine itself and a part is required to do the useful work.
As will be explained later this energy is generally designated
as work. The ratio between the work put to any useful end
and the total amount of work given to the machine is known
as the efficiency of a machine. For instance, suppose that
a certain machine, like a pump, requires one horsepower of
energy to operate it. Suppose that of this amount, one-
half horsepower is used in the. actual lifting of the water
and the remainder is used in overcoming the friction in the
pump. Then the efficiency of the pump is 50 per cent.

Elements of Machines. All machines, regardless of their
intricacy, may be reduced to the elements of machines, or
the simple machines, as they are called. These comprise

186

Digitized byLjOC5QlC

FARM MACHINERY 187

the fimdaonental devices for modifying forces and motions.
They are six in number, and are the lever, the wheel and axle,
the incUned plane, the screw, +he wedge, and the pulley.

Essentials of a Machine. Any machine to be satisfac-
tory must fulfil at least four requirements. First, it must do
the work required of it satisfactorily; for instance, a har-
vester must cut the standing grain and bind it into bundles
with never-failing accuracy. Second, the machine must do
its work efficiently; that is, it must require little power to
drive it, as in the case of horse-drawn machines, where the
draft must be low. Third, the parts of the machine must be
strong enough to resist breakage. Fourth, the machine
must be so designed as to be durable, or able to resist wear;
such parts that are subject to wear should be capable of
adjustment or replacement.

The first two of these requirements demand proper con-
struction on the part of the machhie and skillful adjustment
and management on the part of the operator. The nmnber
of farm machines now manufactured is very large, and in
most cases there are several types and sizes of a machine for
each kind of work. Each machine will do its best work and
render the best service when used under the conditions for
which it is made to work. The part of this text devoted to
farm machinery is planned, in the main, to give instruc-
tion in the selection, adjustment, and operation of the various
farm machines required in general farm practice. In addi-
tion, tbfere will be a discussion of the principles involved in
the strength and durabihty of a machine.

Friction. As a machine operates, there must be at cer-
tain points a sliding of one smiace over another. It matters
not how carefully the surfaces may be prepared there is
always some resistance to the sliding, which resistance is
known as friction. The magnitude of this resistance in

Digitized by

Google

188 AGRICULTURAL ENGINEERING

friction varies much with conditions and it is desirable in
most instances to keep it as small as possible, as it is a waste
of energy or power and lowers the eflSciency of the machine.
There are instances where friction is highly essential, as in
the case of the transmission of power by means of a belt, or
the use of friction in the friction clutch in engaging a part at
rest with a revolving part. The shoes of the clutch slip
when first engaged, allowing the parts at rest to attain speed
slowly, thus relieving the machine of severe shocks, but
finally they furnish enough resistance to sUpping to transmit
the full power of the machine. The ratio between the force
holding the two smiaces together and the force necessary to
slip one smiace over the other is called the coefficient of
friction. Thus if a body weighing 10 pounds requires a hori-
zontal force of 1 pound to move it over a level siuiace, then
the coeflScient of friction equals .1. In most instances it is
desirable to keep the coefficient of friction as low as possible,
which is done by making the sliding parts of the machine of
materials which give a low coefficient of friction, and by
applying a lubricant between the surfaces.

When two surfaces in contact are at rest for a time they
seem to interlock, so that a greater force is required to cause
them to start to slide over each other than to continue the
movement after sliding begins. The friction of rest is there-
fore greater than the friction of motion.

Rolling Friction. When a body with a circular cross-
section is rolled over a plane surface, some resisttnce is
offered, but not as much as in the case of sliding. This
resistance is due to a compression or indentation of the sur-
faces in immediate contact; hence rolling friction is less with
•hard bodies. Since rolling friction is so much less than
sliding friction, rollers are often inserted between two sur-
faces which would otherwise sUde over each other.

Digitized by

Google

FARM MACHINERY 189

Lubrication. To reduce friction between two sliding sur-
faces and to reduce the wear and heating, it is common
practice to apply some substance which will adhere to each
of the surfaces in a thin layer, smoothing them, and pre-
venting them from coming in such close contact. Such a
substance is called a lubricant. The friction really takes
place between two surfaces of the lubricant.

Oils and greases are generally used as lubricants.
Graphite, which is carbon in a very finely divided state, is
often used in connection with oils, and has the property of
smoothing the smiaces. Mica finely divided is used in the
same way in axle grease.

Choice of a Lubricant. It is desirable that lubricating
oil be as Ught and thin as possible, and still heavy enough,
or having enough "body," to prevent being squeezed out
from the smiaces in contact. Heavy oils and grease, being
more viscous, give a higher coeflScient of friction, and are
not adapted to surfaces moving over each other at high speed.
Thus Ught oils are chosen for machines running at high
speeds and where the pressures between the lubricated sur-
faces is not great, as in the case of cream separators. Heavy
oils and greases are used where the pressure is great and the
motion slow, as on axles. Manufacturers provide special^
lubricants for nearly every purpose, and it is well that special
oils be used as far as possible. Gas engine cylinder oil is so
made as to stand high temperature; and although other oils
may be as good a lubricant at normal temperature, they
would be worthless at the temperatures prevaihng in the gas
engine cylinder.

Table of Coefficient of Friction. The following table*
indicates in a general way the influence of smiaces of different
materials and different lubricants upon friction.

♦From "Bearings and Their Lubrication," by L. P. Alford.

Digitized by

Google

190

AGRICULTURAL ENGINEERING

CoejBficierU of friction of various surfaces.

Surface in contact

Condition of the
surface

Mutual arrange-
ment of the fibers

Coefficient
of friction

Oak on oak
Oak on oak
Beech on oak
Cast-iron on oak
Cast-iron on cast-iron
Cast-iron on cast-iron
Cast-iron on wrought iron
Cast-iron on bronze
Balls on hardened steel
Rollers

Dry

Oily

Coated with tallow

Dry

Oily

Coated with lard

Perpendicular
Parallel

0.336

0.108

0.055

0.078

0.152

0.144

0.053

0.070

0.002*

0.0099*

Fig. 100. A plain
bearing.

^Approximate values; coefficient of friction varies with speed and load.

Bearings. The bearings are the parts of a machine which
contain the rotating parts. When the bearings are a sepa-
rable part of the machine they are often called boxes.
Bearing should be designed, first, from
material which will give a low coeflScient
of friction; second, so that the surfaces
may be thoroughly lubricated; third, from
materials that will resist wear or which
can be easily replaced; and fourth, in most cases they
should be adjustable for wear.

A bearing which is made in one piece and is separable
from the rest of the machine is styled a solid box. A bearing
supported on pivots or in a socket
which will permit its axis to be moved
easily is called a self-aligning bearing.
The rotating part which comes in
contact with a bearing is usually desig-
nated as the journal. The journal is
generally made of a harder material Fig. loi. a seif-aiign-
than the bearing. Thus the journal
is usually made pf steel and the bearing of brass, bronze,

Digitized by

Google

FARM MACHINERY 191

or babbitt. When made of different materials there is less
tendency for the surface to become rough and abraded.

Roller and Ball Bearings. Boiler and
ball bearings substitute rolling friction for
sliding friction. Such bearings are usually
much more expensive than plain bearings,
but in many places the extra expense is ^^^' bearing ^^"
justified. Roller bearings furnish a very
satisfactory means of holding a supply of the lubricant and
prevent binding and heating, due largely to misalignment.

Fig. 103. A roller bearing for wagons. The hub of the wheel fits over
the rollers shown.

Ring Oiling Bearings. A ring oiling bearing has a
reservoir of oil underneath the shaft, or joiunal, into which a
ring resting on the upper side of the shaft is allowed to dip,
and as the shaft rotates the oil is carried up onto the shaft,
Hn ^^asLj^Mjg^^^ where it spreads out to
|Jnikp HBHIJ^S^^B ^^^^ ^^^^' thoroughly lu-

bricating the bearing.
Such a bearing is very
desirable for a machine in

Fig. 104. A ring oiling bearing.

continuous service

Inclosed Wheel Boxes. It is customary onMihe best
machines that are to be subjected to much dust, to eitdoae
the outer end of the wheel boxes and provide a collar at the
inside end of such a construction as to practically exclude all
dust. The lubricant is usually "hard oil" or heavy grease,

Digitized by

Google

192 AGRICULTURAL ENGINEERING

supplied by screwing off the inclosed end of the wheel box.

The grease thus works toward the inside end of the box and
still further assists in excluding the
dirt and grit.

Oil and Grease Cups. The gen-
eral character of a machine can often
be determined by the kind of oil and
Fig. 105. An Inclosed grease cups used on the machine,
w ee ox. ^^ machine should be purchased

which does not have an adequate provision for lubricating

all bearings.

Babbitting Boxes. Babbit metal is a mixture of several

metals having a rather low melting point, and is used to line

boxes. Genuine babbitt metal is mixed in

the proportion of 1 part of copper, 2 parts of

antimony, and from 6 to 24 parts of tin; but

the name is applied to many combinations of

metals used as a Hning for boxes. Besides

furnishing a very satisfactory metal for a

bearing, babbitt metal can be quite easily

replaced.

In preparing to babbitt a box it is neces-
sary to be provided with a melting ladle and

a fire, preferably a forge fire, to heat it. The

worn babbitt which is to be replaced is ^^feJd^oii^cup!^*

carefully removed with a cold chisel and the

f^^BB) ^^ freed from grease and moist-
|H9H ure. The shaft is carefully blocked
^I^K^ into position, leveled and centered,
^V and the ends of the box closed by
Tig. 107. A grease cup for cardboard collars fitting around

feeding hard oil. ^j^^ ^j^^^ ^j j^^jj j^ pj^^^ ^^^

putty or stiff clay mud.

Digitized by

Google

FARM MACHINERY 193

If the box is solid, a piece of writing paper is wrapped
around the shaft, or journal, to give clearance or to prevent
the box from being too Ught. This paper is held in place by
a cord which bums up and leaves a useful oil groove. If the
box be split, or made in two halves, cardboard hners should
be inserted between the halves, fitting against the shaft to
divide the babbitt. Notches may be cut in these liners to
let the molten metal flow from one side to the other. When
hardened, the metal in these notches may be broken by driv-
ing a cold chisel between the halves of the box.

It is usually best that the boxes be warmed before pour-
ing the metal, and the metal should be hot, to insm-e that it
will fill every part of the box. The metal is usually poured in
through the oil hole. When the metal has hardened and the
box removed, the oil hole should be drilled out, and, if the box
is a large one, oil grooves should be cut to lead the oil away
from the oil hole, to insure that all parts of the bearing will
be covered with oil. Often an old machine, when babbitted,
will run like a new one, the rattle and vibration due to the lost
motion in the bearings being overcome.

Adjustment of the Bearings. The proper adjustment of
a bearing requires much skill. If the bearing be too tight, it
will heat, and, if too loose, it will knock and also heat. A good
rule to follow is to screw the top of the box down upon paper,
cardboard, or metal strips (called hners) between the halves
of the box until the box is rigid, selecting liners of such thick-
ness as will make the box fit the shaft as tightly as possible,
yet offering no resistance to the free turning of the shaft.

QUESTIONS

1. Define a tool. An implement. A machine.

2. What is meant by the efficiency of a machine?

3. Name the elements of a machine.

7—

Digitized by

Google

194 AGRICULTURAL ENGINEERING

4. What are the three essentials of a practical machine?

5. Why is the selection of a machine important?

6. What is friction?

7. Define the coeflScient of friction.

8. What are some of the conditions that modify the coefficient of
friction?

9. What would be the draft on ice of a sled weighing 4000 pounds
if the coeflScient of friction between the runners and the ice is 0.025?

10. Mention several instances where friction is especially useful.

11. Why is friction of rest greater than friction of motion?

12. What is the cause of rolling friction?

13. What are the purposes of lubrication?

14. What kind of lubricant should be used on a machine like a
harvester?

15. Of what value is graphite as a lubricant? •

16. What should be taken into account in the design of a bearing?

17. Why should the material used for the bearing be different from
that of the journal?

18. When are roller and ball bearings best?

19. Explain t'ne process of babbitting a box.

20. How should a bearing be adjusted?

Digitized by

Google

CHAPTER XXXI
MATERIALS

Importance of Quality. The durability of a machine
depends largely upon the quality and character of the mate-
rials used in the construction of it. It is obvious that a
knowledge of the properties of these materials \rill be use-
ful to those who have to do with the selection and manage-
ment of machinery.

Wood. Twenty-five to forty years ago the framework
of farm machinery was made largely of wood. At that
time wood stock of the first quality and of the most desir-
able varieties could be obtained cheaply. The increase in
the cost of wood, due to its scarcity, and the decreasing cost
of manufacturing iron and steel has led to a more extended
use of metal. The wood used in the construction of farm
machinery, since it must undergo rather severe service,
should be of selected quality. Carefully selected, well-sea-
soned heartwood in the only practical kind to use.

Wood is influenced more or less by moisture, and for
that reason should be carefully protected by paint. A
combination of iron and wood parts is Ukely to give trouble
by becoming loose, due to the shrinking of the wood. Parts
subject to much vibration, like the pitman of a mower, can
best be made of wood. Excessive vibration and shocks
tend to cause steel to crystallize.

Some of the more common varieties of woods and forms
of metal used in the construction of farm machinery will
now be discussed.

195

Digitized by

Google

196 AGRICULTURAL ENGINEERING

Hickoxy is a very dense, heavy wood of great strength
and elasticity. It is the hardest and toughest wood used in
the construction of farm machinery and vehicles. It is
preferred to all others for axles, buggy spokes, shafts, etc.

Oak is a hard wood but not so tough as hickory. It is
used to some extent for wagon axles, doubletrees, and gen-
erally for parts where stiffness is required. The best kind
of oak for these purposes is white oak. Red oak or black
oak is not so hard and stiff.

Ash is hard, tough, and elastic, and for that reason is
quite generally used for handles of hand tools, such as forks.
It is a white, coarse-grained wood

Maple. Hard, or "rock maple," is a hard, fine-grained
wood which is quite stiff, and is being used to some
extent as a substitute for hickory.

Beech is a hard, strong and tough wood of very close
grain and will take a very high poUsh.

Birch. Black birch is a dark, close-grained, tough
wood. It is used to some extent for wagon hubs, on account
of its resistance to checking.

Poplar is a wood which may be obtained very free from
knots. It is hght yellowish in color, has a close grain, and
is very tough compared with the Ughter woods. It is the
standard material for wagon boxes and buggy panels. Cot-
tonwood, a very close relative of the poplar, is used to some
extent as a substitute.

Pine. There are many varieties of pine to be had.
Long leaf yellow pine has a decided grain and is quite stiff.
It is used largely in the construction of field hay tools and
for similar purposes. White pine is used where soft, light
wood is desired.

Cast-Iron. The cheapest metal used in the construc-
tion of farm machinery is cast-iron. It is crystalline in

Digitized by

Google

FARM MACHINERY 197

structure and it can not be forged or welded. It is
shaped by machine tools, by drilling, turning, or planing.
It is used for the heavy parts of machines, for gears or
where irregular shapes are desired, which may be obtained
by casting molten iron. Cast-iron may be usually de-
tected by the lines and roughness given to it by the sand
mold in which it is cast. It is easily detected upon breaking
by the crystalline structure.

Chilled Cast-Iron. Where a particularly hard surface
is desired, a special kind of cast-iron is used, obtained by
making a part of the mold of heavy iron, which chills the
molten metal as soon as it comes in contact with it and
makes it very hard.

Malleable iron is cast-iron which has been annealed
and reUeved of a part of its carbon by heating in furnaces
for several days. Malleable iron is spft, tough, and some-
what ductile, and is used to replace cast-iron where these
characteristics are required. When broken, malleable iron
shows a soft malleable surface and a crystalline center.

Cast Steel. Cast steel is, in brief, cast-iron less a part of
the carbon. It is less brittle than cast-iron, and is used for
gears and other parts subject to severe stresses.

Mild and Bessemer Steel. Most of the material now
used in the construction of farm machinery is mild or Besse-
mer steel, which is made by a special process. It is a very
tough metal whose stiffness can be regulated by the manu-
facturer by varying the carbon content. It can be easily
forged, but does not weld as readily in an open fire as
wrought iron.

Wrought Iron. Wrought iron is nearly pure iron. It
is very ductile and can be easily forged or welded. The
purest and best grade of wrought iron is known as Norway
or Swedish iron.

Digitized by

Google

198 AGRICVLTVRAL ENGINEERING

Soft-Center Steel. The ability of carbon steel to be
hardened depends largely upon the percentage of carbon
it contains. When hardened, it will take a most excellent
polish, as is desired for plows, but hardened steel is brittle
and will not stand shocks. To overcome this shortcoming,
soft-center steel has been invented, which consists of a layer
of soft steel between two layers of high-carbon steel. This
soft, low-carbon steel lends toughness to the whole plate.
Soft-center steel is quite generally used at the present time
in the manufacture of shovels and plows.

Tool Steel. Tool steel contains a rather high percentage
(0.6 to 1) of carbon, is capable of being hardened and tem-
pered, and has a very close, dense structure. It is used in
the manufacture of hand tools, such as hanmiers, chisels,
etc. A discussion of the strength of materials will be found
in Part VII.

QUESTIONS

1. Why is it important that a good quality of material be used in
the construction of farm machinery?

2. Discuss the merits of wood as a material for farm machinery.

3. Describe some of the special uses for wood.

4. Why is hickory used for wagon axles and buggy spokes?
6. Compare white oak with hickory.

6. Suggest some good uses for maple, beech, birch, poplar, and
white and yellow pine.

7. What are some of the properties of cast-h-on?

8. Describe the process of making chilled iron. Malleable iron.

9. For what purposes is cast steel used?

10. Why are Bessemer and mild steel used so largely in the con-
struction of farm machinery?

11. Describe soft-center steel and its uses. Also tool steel.

12. What is tool steel, and mention some of its properties?

Note : Samples of the various materials used in the construction of
farm machinery should be collected, and machines should be examined
to determine the materials used.

Digitized by

Google

CHAPTER XXXII
THE PLOW

The Plow. The plow is universally recognized as the
principal and most fundamental implement used on the
farm, it being often included, in emblems representing the
great industry of agricultiu'e. The plow is a very simple
tool, if we consider the walking implement, and the sulky
or gang plow is not exceedingly compUcated. Yet in the
selection, operation, and adjustment of the plow there are
many important features to be considered.

The Selection of a Plow. As with* any other imple-
ment, the selection of a plow will depend in a large measure
upon the conditions to be met. A farmer owning a farm
with small fields would not want a steam plow; nor would
a farmer having large level fields want small walking plows,
when a single driver could handle a gang just as well. The
walking plow is useful in small lots and in getting close to
the fence in finishing up the lands plowed with a larger
plow, and for these reasons it should be a part of the equip-
ment of every farm.

Size. The sizes of plow which should be selected is
determined largely by the condition of the soil and the
amoimt of power or the nmnber of horses available. The
average size (width of furrow) for a walking plow is 16
inches, and the horse gang usually has two 12- or 14-inch
plows, or bottoms, as they are called.

Types of Plows. There are three distinct types of plows
upon the market, as classified by the shape of the mold-
board: First, the breaker, with a long moldboard to tiu-n

199

Digitized by

Google

200

AQRIGULTURAL ENGINEERING

the furrow slice of tough sod gradually; second, the general-
purpose plow, to be used for general plowing in stubble and
light sod; and, third, the stubble plow, with an abrupt mold-
board for pulverizing the soil, used only in old ground.
Among these three classes there are numberless shapes of
plows diflScult to classify.

Flgr- 108. The three principal types of plows, showing In order the
stubble, the general purpose, and the prairie breaker plows.

Construction. The moldboard may be made of soft-
center steel or chilled iron; but the latter is used but very
little in the Middle* West, where the soil is of such a character
that the hard-tempered surface of the soft-centered steel is
required to scoiu* properly. Certain localities are furnished
with plows with common cast-steel moldboards; but they
can not be used where many rocks are encountered, in
which case a soft share, at least, must be provided. The
wearing properties of the soft-centered steel share is secured
through its hardness; but to secure hardness a certain

amount of brittleness
must remain, even with a
soft center to the metal.
Adjusting the Walk-
ing Plow. The walk-
Pig. 109. A steel beam walking plow of iug ploW mUSt have itS
the general-purpose type. ^^^^ tumcd doWU

slightly in order to cause the plow to take to tlie ground.
This gives what is called "suction" to the plow, and is
resisted by the upward pull of the draft. It is imperative
that the suction be sufficient, and quite as important that

Digitized by

Google

FARM MACHINERY

201

Fig 110. Illustratlngr method of
using a straight-edge to determine
whether a plow has the proper "suc-
tion.**

it be not too great. With the proper amount of suction a
plow will run evenly, as far as depth is concerned. To test
for suction, lay a straight-
edge on the underline of
the landside when the
plow is turned bottom
side up. If there is an
opening of about H of an
inch between the straight-edge and the landside at the
joint between it and the share, the suction is about correct.
To Uft and bend the furrow slice, a certain amount of
pressiu-e must come upon the outer corner, or wing, of the
share. To resist or carry this pressiu'e, a certain amount
of surface, or "bearing," is provided to rest upon the bottom '
of the furrow as the plow is drawn along. If this bearing
is too great, the plow will be continually tending to turn out
from the land, and if insufficient will turn in the opposite
direction. The amount of bearing, or the width of surface
at the comer of the share, varies with the condition of the

soil,- but \}4: inches is
about correct for a 16-inch
plow. The bearing sur-
face is triangular in shape,
and is usually about 3
inches long.

Steel-beam walking plows have an advantage in clearance,
and for this reason are more satisfactory in plowing imder
trash and weeds. On the other hand, wooden-beam walking
plows are slightly Ughter.

Sulky or Gang I^lows. Riding plows with moldboards
may be divided into two classes, frame and frameless, and
are constructed with and without tongues. The frameless
and Umgueless plows are of the cheaper construction; but,

Fig. 111. A share with the proper
form at the wing. The contact or
"bearing" at C should be about 1%
inches wide for a 16-inch plow.

Digitized by

Google

202 AGRICULTURAL ENOINE^RING

although they have the advantage of lightness, they do not
have certain advantages secured in the frame and tongued
plows. The frame type has the plow connected to the frame

by means of bails or some
similar device. This per-
mits the plow to be hf ted
high out of the ground,
designating it a ^'high-
Uft" plow. This fea-
ture is a decided ad-
vantage for cleaning.

Fig. 112. A frameless and tongueless The framclcSS ploW haS

sulky Plow gruided by the hitch. ^^^ ^j^^^j^ attached di-

rectly to the plow beam by means of brackets. This
simplifies the construction; but frameless plows are not high-
Uft. This type cannot usually be set to **float," so that in
case a rock is struck in plowing the plow may be lifted out
of the groimd without interfering with the carriage or the
driver.

The tongue on the high-class sulky plow is used to steer
the plow by be-
ing connected
to the furrow
wheels by means
of suitable link-
age, thus en-
abling a square
comer to be
turned in either

direction. The ^'''' '''' ^ '^*^*^-"" '"''"'" ^^''^ ^'*''''

tongue gives more complete control over the plow, and, in
the opinion of the author, is an essential part. Another
desirable feature to have on any plow is a footlift, which

Digitized by

Google

FARM MACHINERY 203

enables the driver to control the plow by the feet, leaving
the hands free to drive. The frame plow with a high Uft,
footUfb, and tongue has many complications as far as con-
struction and operation are concerned, but is well worth the
difference in price over a more simple plow. Gang plows
have the same constructional features as sulky plows, except
that two bottoms instead of one are provided.

The Adjustment of Sulky and Gang Plows. In operat-
ing the sulky or gang plow, every effort should be made
to have the plow travel straight to the front and to
have all of the downward pressure, due to Ufting the fm-row
slice, and the side pressure, due to tmiiing the furrow slice,
borne by the carriage of the plow.
To do this the point must al-
ways be turned down sufficiently
to cause the plow to take the
ground at all times. No pres-
siu-e should be allowed on the sole
of the plow, as this will cause
unnecessary friction. All pres-
sure as far as possible should
come on the wheels, which, with
their lubricated bearings, will re-
duce friction to a minimum.

To give the sulky plow suc-

.. .r £ i_ 1 Fig. 114. A plan of a high-

tion, tne rear furrow wneel may uft frame suiky piow showing

1 , J x'l xi^ i_ 1 r j.i_ ^^® manner In which the rear

be iOWereCl until tne neel OI the furrow wheel is set to relieve
, 1.111 1 .ly^i I* the friction on the landslde.

landside lacks about J^ mch of

touching when the plow is placed upon a level sur-
face. To carry the landside pressure, the rear furrow wheel
should be set outside of the line of the landside, usually
about 1)4 inches. It must also be turned slightly away

Digitized by

Google

204 AGRICULTURAL ENGINEERING

from the land, and the front furrow wheel regulated to keep
the large land wheel traveling directly to the front.

Draft of Plows. The draft or pull required to move a
plow at work varies widely with the soil conditions and the
adjustment of the plow. The draft will vary from 4 to 10
poimds to each square inch of cross section of the fiurow slice,
the method of comparision commonly used. In stubble
ground the draft should not exceed 4J/^ pounds per square
inch of the fiurow. Thus a 16-inch plow running six inches
deep will have a furrow with a cross-section of 96 square
inches. If the draft be 4 J^ pounds per square inch the total
draft will be 432 pounds, an easy load for three 1300- to
1400-pound horses.

A sulky plow with a driver of medium weight will run with
as hght draft, when in proper adjustment, as a walking plow.
This is due to the reduction of sole and landside friction. A
plow out of adjustment will often pull half again as heavy as
it should.

In making a selection of a sulky plow, care should be taken
to see that all parts subject to wear can be easily renewed.
The greater part of a sulky plow is not subject to wear and
will last indefinitely if not broken. The modem plow
must have wheel boxes which will not only exclude all dirt
but also provide a magazine for a Uberal supply of grease.
Many sulky plows are now constructed with too light a frame.
Choice should be made of the heavy, rigid plow, even if the
cost is sUghtly higher and the draft slightly greater.

The Disk Plow. There are two conditions under which
the disk plow will do good work. The hard, dry soils of some
of the Western states are more easily subdued by means of
the disk plow than any other. These soils at certain times
of the year are turned up in lumps by the common plow, but
the disk plow cuts its way through the lumps and breaks

Digitized by

Google

FARM MACHINERY 205

them up. Yet the disk plow cannot be used in extremely
hard ground, such as mi^t be found in a road, as it could
not be kept in the ground. The other soil condition to which
the disk plow is well adapted is where the soil is so sticky
that the moldboard plow fails to scoiu* well, as in heavy
clay or gumbo soils. The black, waxy soil found in Texas
and other parts of the South is such a soil. The disk plow
with its scraper to clean the disk will turn a f mrow regardless
of the scouring properties of the soil. Where the moldboard

Fig. 115. A modern disk gang: plow at work.

plow will do good work, it is to be preferred to the disk plow.
As generally constructed, the latter is a very clumsy imple-
ment and very heavy, the weight being necessary to keep
the plow in the ground. Claims for its lightness of draft
cannot be substantiated by tests when compared with mold-
board plows under favorable moisture conditions. Often
the disk plow is given credit for doing more work than it
actually performs, in that the bottom of the furrow is not
flat and measurements are often made of the deepest point.
The diameter of the disk proper varies from 20 to 30
inches in different plows. A 24-inch disk will do the most
satisfactory work under usual conditions. It pulverizes the

Digitized by

Google

206 AGRICULTURAL ENGINEERING

soil to the best advantage, — more so than a smaller disk, —
and is not of as heavy draft as a larger disk. A disk blade
26 or 28 inches in diameter can be used for a longer period,
because much more metal is provided for wear.

The disk plow does not have a tongue and does not make
as goodcomers as the modem high-class sulky plows. If the
disk is of proper shape and size, the plow pulverizes and mixes
the soil thoroughly, which features are essential in good plow-
ing. This plow will cover standing weeds to good advantage,
but loose trash is troublesome. It cannot be used at all in
tough sod.

It is a mistake to try to cut too wide a furrow with a disk
plow. A furrow with a width greater than 8 inches results
in more or less "cutting" or "covering."

The vital parts of a disk plow are the disk and its bearing.
The former should be constructed of the best of material,
for which the faith of the manufacturer must be taken, and
the bearing should have plenty of material to resist wear
and reliable means of excluding dirt and providing lubrica-
tion.

Deep -Tilling Machine. This is a new machine which
has come upon the market within the last two years, and, as

far as providing
a means of plow-
ing the soil to a
greater depth
than hitherto is
concerned, it is
a success. The
machine is a disk
gang plow with
the second or
„. rear disk set to

Fig. 116. A deep-tilling machine.

Digitized by

Google

FARM MACHINERY 207

plow a furrow in the bottom of the furrow made by the first.
In this way it is entirely possible to plow to a depth of 16
inches or even more. The disks are large and they do
the best work when cutting a furrow 12 inches wide.

The draft of this tool is surprising. When tested in a
loam soil with a clay subsoil, the draft, when plowing a 12-ihch
furrow and 16 inches deep, was between 800 and 900 pounds.
A 16-inch sulky plow when forced to its capacity for depth
(eight to nine inches) gave a draft between 900 and 1000
pounds, or about 100 pounds more. By comparing the
sizes of these various furrows it is to be noticed that the draft
of the tilling machine was very satisfactory. Again, it would
be quite impossible to plow so deep with anything except a
special plow of this character.

Hillside and Reversible Plows. The hillside plow is
a reversible plow adapted to a field with so much slope that
it would be quite impossible to throw a furrow uphill. The
plow is changed from a right-hand to a left-hand plow by
revolving the plow so that the furrow is turned either to the
right or to the left.

The reversible plow was formerly confined to the hillside
type, yet there is a tendency at the present time to make a
more extended use of
this type of plow. Its
use in the irrigated
sections, where dead
furrows are to be avoid-
ed if possible, is of
great importance. The
advantage of dispens-
ing with dead furrows

n ^Jl J aU Fig. 117. A reversible disk plow. This

m any tiela, and tnUS piow is made to tum a right or left fur-
1 . ,1 t row by swinging the hitch from one end

leaving the surface to the other.

Digitized by

Google

208 AGRICULTURAL ENGINEERING

level, is worthy of consideration. In Europe, the reversible
plow has been in more extended use than in this country.

The moldboard type of reversible plow consists of two
plow bottoms, a right- and a left-hand, which are used alter-
nately. These plows do not have many of the conveniences
of the high-Uf t sulky and do not possess the usual provisions
for relieving the landside friction by placing the load on the
carriage. It is, however, an entirely practical tool. The
reversible disk plow is so arranged that by swinging the team
and hitch about to the opposite direction, the inclination of
the disk is changed, but the carriage is left unchanged and
is simply drawn across the field in the reverse direction. It
would seem that this implement has reached a higher state
of development than its moldboard mate.

Tractor Gang Plows. The use of the tractor for plow-
ing requires for the best service special plows adapted to

Fig. 118. An engrljie gang plow.

the special requirements of tractor power. Tractor gang
plows are made with moldboard and disk plows and range
in size from two to fourteen furrows.

In general there are two types, one the flexible beam
shown in Figure 118, in which each plow or pair of plows
may be handled independently, and the rigid beam, Fig. 118a,

Digitized by

Google

FARM MACHINERY 209

in which the plows are fastened rigidly together and raised
or lowered as a unit. The flexible beam type consists in a
heavy triangular frame, carried on wheels, all or a part
of which are arranged to castor or are guided by the hitch

Fig. 118a. Rigid beam gang plow.

through suitable Unkage. The plows are attached to the
rear of the frame and are generally controlled by levers ex-
tending forward over a platform placed on the frame. These
levers may be attached either to a single plow or to a pair.
Quite a little variance is found in the location of the gauge
wheel which regulates the depth of the furrow. The gang
wheel should be so located that the furrow depth will be
influenced as little as possible by an uneven surface.

The "rigid beam" type of tractor plow is used exclusively
for the disk gang and is generally confined to small sizes,
two to four bottoms when made for moldboard plows. It
is desirable with small tractors to have an outfit which may
be operated by one man. For this reason the levers are
generally turned toward the front where they may be con-
veniently reached. Disk tractor plows resemble horse disk
gangs except that they are made much heavier. Plows are
now made with power lifts enabling the tractor operator by
pulling a rope to engage a clutch which sets in motion
mechanism which raises the plows by power from the wheels
of the gang plow. The power lift is adapted to both the
flexible and rigid beam types of tractor gangs.

Digitized by

Google

210 AGRICULTURAL ENGINEERINO

Adjusting the tractor gang consists primarily in setting
the plows for the proper amount of suction and proper spac-
ing. The gang should be attached to the tractor so as to
cause each plow to be drawn straight through the soil.

Any type of plow bottom, may be used in the tractor
gang plow from the sod to the stubble bottom. Shares are
now made "quick detachable," enabling the shares to be
removed for sharpening by loosening one nut or lever.

QUESTIONS

1. Why is the plow considered the principal implement on the farm?

2. What are some of the most important factors to be considered
in the selection of a plow?

3. How is the size of a plow designated, and what are some of the
common sizes?

4. What are the distinct plow tjrpes on the market?

6. Of what materials are the plow moldboard and share made?

6. Describe the adjustment of a walking plow.

7. What is meant by the suction of a plow? The bearing at the
wing?

8. What is the difference between a frame and a frameless plow?

9. Describe what is meant by high lift.

10. How should sulky plows be adjusted?

11. How is the draft of a plow kept low by adjustment?

12. What constructional features should be given consideration
in making a selection of a sulky plow?

13. Under what conditions will the disk plow work better than the
moldboard plow?

14. What are the common sizes of disks and disk plows, and what
size of furrow will they turn?

15. Describe the construction of the deep-tilling machine.

16. Describe the construction of hillside and reversible plows, and
explain their use.

17. Describe the construction of the moldboard engine gang.

18. How are the plows raised and lowered?

19. What adjustments are of primary importance?

20. Describe the construction of the disk engine gangs.

Digitized by

Google

CHAPTER XXXIII

HARROWS, PULVERIZERS, AND ROLLERS
HARROWS

Utility of the Smoothing Harrow. Perhaps there is
no other tillage tool on the farm which is more effective than
the common spike-toothed smoothing harrow, when used
under the proper conditioi^ and at the proper time. It
smoothes and pulverizes the smf ace, producing a fine tilth,
which not only prevents
a loss of moisture by
evaporation but also
destroys a multitude of
weeds at the time when
they are the least able
to withstand cultivation.

Selecting a Smooth-
ing Harrow. The stand-

j , i? J.T. J • ^^^- ^1^- ^ modern U-bar smoothing

ard harrow of the day is harrow with protected tooth bars. A har-
,, ill 1 row cart is attached.

the steel lever harrow

for four horses, covering a width of 15 feet or more. A
harrow with a spread of from 10 to 15 feet is a size suitable
for a three-horse team.

A lever harrow, which enables the teeth to be inclined
forward for penetration and backward for smoothing, costs
shghtly more than a plain harrow or even an adjustable tooth
harrow; but the harrow at most is not an expensive implement
and the lever harrow is well worth the difference in cost. One
of the principal advantages of the lever harrow lies in the
convenience in cleaning. The adjustable tooth has a clamp

211

Digitized by

Google

212 AGRICULTURAL ENGINEERING

which permits the teeth to be held in a perpendicular position
when drawn in one direction or in an inclined position when
drawn in the opposite direction. The barrow is reversed by
changing the evener from one side of the harrow to the other.

All harrows may at first seem alike, yet there is much
difference in their construction. There is no doubt but that
some harrows are made as cheaply as possible to sell for a
low price. Of course there are conditions where the soil is
easily cultivated and a light harrow is desirable ; yet, as a rule,
the amount of cultivation performed is in proportion to the
weight and number of teeth in the harrow. Stony ground
will require a heavier construction than would otherwise be
necessary.

Construction of the Smoothing Harrow. The tooth

bars are commonly made of the so-called U bar or pipe. The

former seems to be the stronger for the weight of metal

used. The teeth may be had in two sizes, one-half or five-

■^.^ B / eighths inch square, the

^"Y W^ If j^ larger, of course, being

I n ojl ,,n^-, nf adapted to heavy serv-
' /3^a^^BBii»fcfc*- ice, All the teeth

should have large heads
to prevent loss should a
fastener become loos-

Flg. 120. A pipe-bar smoothing har- ,

row. Common methods of fastening eneO.. llie UUmber OI

teeth are illustrated. x j.i- • j? • x

teeth vanes from six to
eight per foot of width. It stands to reason that the greater
number of teeth will do more in pulverizing the soil.

For use in orchards, the harrow with protected tooth
bars has a decided advantage, since the bars will not do
much damage by catching upon the trees. As a smoothing
harrow is too wide to pass through the average farm gate, it
should be convenient for dissembling and assembUng.

Digitized by

Google

FARM MACHINERY 213

The Spring-Tooth Harrow. The spring-tooth harrow,
with flat spring teeth bent ahnost to a complete circle, is a
tool that is not in general use in America, but implements
of a similar character are used to a large extent in Europe.
It should be classed as
a cultivator rather than
a harrow. It is adapted
to hard, compact soils
which require a tool of
good penetration. The
teeth have such long
blades with so much

^, , ,- , . Fig. 121. A spring-tooth harrow.

spnng that the machine

is not damaged in passing over stones or low stiunps.
The draft of a spring-tooth harrow will depend upon the
adjustment given to the teeth, but under average condi-
tions it greatly exceeds that of a smoothing harrow.

The Harrow Cart. Probably there is not another imple-
ment attachment that can be bought for the same money that
will dispense with so much hard labor as the harrow cart. To
be a satisfactory device it must be rigidly built with angle or
U-bar arms extending to the harrow evener, with provision
for the cart wheels to castor in turning. The wheels should
be high, 32 inches being a good height, and provided with
tires about three inches wide. They should also have dust-
proof removable boxes with easy means of lubrication.
Lastly, it should not be overlooked that the cart should
be provided with a comfortable seat and springs to support it.

Utility of the Disk Harrow. The disk harrow is an
implement well adapted to deep surface cultivation. For
this reason it is used for a variety of purposes. To prepare
plowing for seed in the spring or stubble for plowing in the
fall, it is equally useful. For covering broadcasted seed in

Digitized by

Google

214 AGRICULTURAL EN&INEERING

com stalk ground it has many advantages over the shovel
cultivator. In the first place it is more rapid, and, more-
over, a double disking will effectively reduce the stalks.
In subduing a sod, there is no other tool that will do the
work of the disk harrow. In dry-farming locaUties it has
been found to be one of the best tools to produce a soil
mulch for preserving the soil moisture. Orchardists use it

Fig. 122. A disk harrow at work.

for cultivating orchards. It is used in renewing alfalfa fields,
as it cuts or splits the crowns of the plants, thus thickening
the stand.

The disk harrow can be made to do the work of the stalk
cutter and at the same time cultivate the ground in the early
spring, preparing it for plowing. As a rule two diskings will
not cut comstocks as well as going over the field once with a
stalk cutter, but nevertheless a good job is done. This

Digitized by

Google

FARM MACHINERY 215

system of disposing of the stalks and cultivating the soil be-
fore plowing cannot be too highly commended. Many
weeds are destroyed and a better seed bed is obtained upon
plowing.

Construction of the Disk Harrow. The standard disk
harrow has full round disk blades, sixteen inches in diam-
eter and about sixteen in nmnber, spaced six inches apart.
This is the four-horse machine. Smaller disk blades do
not give sufficient clearance, and larger sizes do not do
as eflFective work. The sixteen-inch disk rotates faster than
a larger disk and so pulverizes the ground more, and it also
has less bearing surface imder the working edge, insuring
greater penetration.

Disk harrows have one lever by means of which both
disk gangs are adjusted at the same time, or two levers, one
for each gang, permitting individual adjustment. The two
levers are almost essential when "lapping half,*' or allowing

Fig. 123. A full-blade, two-lever disk harrow with tongue truck.

Digitized by

Google

216 AGRICULTURAL ENGINEERING

the disk to extend half way over the work of the previous
round. The merit of this method lies in the fact that the
ground is left nearly level, while a single disking will leave the

ground slightly ridged.
When this method is fol-
lowed, the disk gang work-
ing on the once disked
' ground finds less resist-
, ance than the gang work-
ing in the undisked ground.

Pig. 124. A cutaway disk harrow. By Setting the gang in

the loose soil at a sharper
angle, the machine is balanced and the soil pulverized more
than otherwise. The two-lever machine also has a decided
advantage in hillside work. The tendency of the machine
to crowd downhill may be overcome to a large extent by
a separate adjustment of the gangs.

•Types of Disk Harrow. Disk harrows are built in
three general types, as far as the construction of the disk is
concerned. First, there is the fvllriladed disk with solid per-
fectly round edges; second, the cutaway or cut-out disk,
which is like the full-bladed disk except that notches are
cut out of the edge, leav-
ing short points to enter
the ground; third, the
spading disk harrow
which consists of a series
of sharp blades curved at
the end and made up into ^ -^-

. - till Flgr- 125. A spading disk harrow.

a sort of sprocket wheel.

For average conditions the full-bladed disk is the best.
It has a greater pulverizing action, is stronger, and is more
effective in cutting up trash and stalks. Another very im-

Digitized by

Google

FARM MACHINERY

217

portant advantage of this type is the convenience of sharpen-
ing. These disks may be sharpened to a good edge by means
of any of the disk sharpeners which will do
good work. About the only way that the
notches of the cutaway disk may be sharpened
is by removing all of the disks and grinding
them to edge on an emery wheel. The blades
of a spading harrow are sharpened by heating
each individual knife and drawing out the
edge with a hammer while hot.

The cutaway harrow is very deceiving in
the amount of work it does. The blades
sprinkle the soil over the surface in such a way
that the unstirred soil imderneath is hidden.
This harrow has a decided advantage in cul-
tivating and renovating old pastures. Where
the fuU-bladed disk would cut the stubble up
and destroy it, the cutaway will loosen the
soil in such a way as to stimulate growth. „. ,^^ .

*^ ^^ Fig. 126. A

In the amount of work done, the spading piow-cut disk
harrow is much uke the cutaway. Ihe prm-. harrows. Note
cipal advantage of the spading harrow lies in center.
its ability to work in wet ground, when the fuU-bladed
disk would be sure to clog.

The "plow cut*' disk has a bulged or raised center, it being
claimed that the soil will be more nearly turned over when
coming in contact with this center. The name might imply
some sort of plow action, but the work of this type, as far as
the writer has observed, does not differ much from the
ordinary disk harrow.

Alfalfa Harrow. The alfalfa harrow is a special tool
with sharp spikes arranged as disks in the frame of a common

Digitized by

Google

218 AGRICULTURAL ENGINEERING

disk harrow. This new implement is certain to become

very popular for cultivating alfalfa fields.

Scrapers. A disk harrow should be provided with

scrapers or cleaners which
will keep the disks clean
under all conditions. The
scraper with a rather nar-
row chisel blade which
can be moved from the
center to the outside of
the disk is very satisfac-

Fig. 127. An alfalfa harrow. ^ , , _

tory and is used upon
a large number of modem disk harrows.

Bearings. The part that receives the most wear, except
the cutting edges of the disks themselves, is the bearings.
Both chilled iron and wooden boxes si^e used. The wood
seems to be the more satisfactory, not only on account of
durability, but also on account of the ease of replacement.
Maple boiled in oil is generally used for the bearings, yet any
hard wood might answer.

Ball-and-socket joints between the disks are not generally
satisfactory. If the bearings
do not care for the entire
thrust of the gangs, bumper
plates seem to be the most sat-
isfactory devices. These are
large oval washers on the ends

of the gang bolts which run pig. 128. a good form oTIbearlng

through the center of the disks. '°" ^*'^ '^^""^'"•

Tongue Truck. The modem disk harrow has a tongue
truck. This device relieves the horses of the most tiresome
part of the work when the harrow is used on loose and rough
ground. With a tongue truck, side lashing is prevented.

Digitized by

Google

FARM MACHINERY 219

Trucks which have tongues assist in keeping the team straight
and also prevent the horses from backing into the harrow.
The trucks should have reasonably large wheels and be
strongly made. The axles should provide for lubrication,
be dust proof, and have interchangeable boxes.

Transport Truck. Another convenient device to use in
connection with the disk harrow is the transport truck,
especially if the harrow is to pass over any hard road. This
device consists of wheels mounted on levers in such a manner
that the gangs may be lifted from the ground, thus securing
the desired protection.

Fig. 129. A harrow attachment for a plow at work.

Harrow Attachments for Plows. Those who have had
the experience know that a harrow will do the most effective
work when following the plow. Attention has been called
by agricultural writers to the desirability of harrowing each
day's plowing before the close of the day. The harrow attach-
ment has been designed to harrow and smooth each furrow as
soon as tmned. There are three types in use, one with blades
which resemble those of a pulverizer, another is a rotary
affair with blades like a spading disk harrow, and still another

Digitized by

Google

220 AGRICULTURAL ENGINEERING

kind has small round disks. Each of these works much like
the machines after which they are patterned. They are
made in sizes suitable for either sulky or gang plows, and
are quite easy to attach. They interfere slightly with the
adjustments of the plow, but this matter can easily be over-
come. The draft of those for sulky plows will vary from
50 to 100 pounds, depending upon the pressure applied.
This means that the attachment provides about one-half
to two-thirds of a load for one average horse.

LAND ROLLERS

Types of Rollers. The plain, smooth land roller has
been replaced to a large extent by tubular, corrugated, or

disk types. The change
has been due to some of
the objectionable features
of the work of the smooth
roller. It is desirable, in
most instances, not to
leave the surface of the
ground perfectly smooth
and compact. It is true
that for crops to be har-

Fig. 130. A plain land roller. ^ , .^, .

vested with the mower
this feature is desirable, but a smooth surface usually means
an unnecessary loss of moisture. On a smooth surface there
is no soil mulch, and the
wind has a greater dry-
ing effect.

Of the various types
of rollers recently placed

upon the market, the '

disk roller, composed of Fig. i3i. a dUk roiier.

Digitized by

Google

FARM MACHINERY 221

cast-iron disks with wedge-shaped treads, spaced about
four inches apart and weighing about 100 pounds per
foot of width, is perhaps the most satisfactory. This imple-
ment not only thoroughly packs the soil beneath the surf ace
but also collects and crushes the clods and leaves the
surface slightly rough and covered with a mulch.

Selecting a Roller. In selecting a roller, the bearings,
strength of construction, and weight are the principal fea-
tm-es which should be given consideration after the type
of machine has been decided upon. Hard-wood boxes
make the most satisfactory bearings. If the ground is
uneven, a flexible frame should be chosen, as there will not
only be less chance of breakage in the roller but better work
will be performed.

PULVERIZERS

The name pulverizer is given to a variety of tools. It
usually designates certain curved-tooth harrows of the Acme
type and also rollers of the
cast-iron type. In some
locaUties the disk harrow
is referred to as a pulver-
izer. It seems, however,
that the implement best
described bv this name Fig. 132. a pulverizer wim rake

•^ attached.

is the one with curved

spring knives, either with or without a levehng rake. This
tool has not become very popular with farmers generally,
but it seems to be gaining favor of late. The tendency
has been to try to perform the same work by means of
the common smoothing harrow.

The pulverizer does efficient work in producing a fine
tilth. It is especially useful in destroying small weeds just

Digitized by

Google

2n« AQRWVLTVHAL rNGINEERING

coining through the ground. The knives tear the weeds
out and the rake behind drags them free of the soil and leaves
them on the surface to be destroyed by the sun. The drag-
ging action of the pulverizer is also very good in leveling an
imeven surface. The draft of the pulverizer is less than
that of the disk harrow, an eight-foot pulverizer drawing
about as hard as a six-foot disk harrow.

QUESTIONS

1. What is the work of the smoothing harrow?

2. Describe the difference in construction between the adjustable
tooth harrow and the lever harrow.

3. Describe some of the important constructional features of the
smoothing harrow.

4. Describe the construction of the spring-tooth harrow, and under
what conditions it will render the best service?

5. Why is the harrow cart useful and what should be its construc-
tion?

6. For what work is the disk harrow adapted?

7. Describe some of the general features of the construction of the
disk harrow.

8. What are the three general types of disk harrows?

9. Describe the plow-cut disk blade. The alfalfa harrow.

10. What is the purpose of the scrapers on a disk harrow?

11. Why are the bearings important on a disk harrow?

12. Of what use is a tongue truck?

13. Describe the construction of harrow attachments for plows.

14. Describe three types of land rollers.

15. Explain some of the important points to be considered in select-
ing a land roller.

16. To what purpose is the pulverizer adapted?

17. Describe the construction of the curved-tooth pulverizer.

Digitized by

Google

CHAPTER XXXIV
SEEDERS AND DRILLS

Utility of Seeders and Drills. The seeder should be used
only where the drill is impractical, as it is not a machine
adapted to the most improved methods of farming. The
drill enables all the seed to be covered at a imiform depth
and to be very imiformly distributed. The broadcast seeder
may distribute the seed imiformly, but the harrow or other
implement which follows it will not cover the seed at a uni-
form depth, meaning that a part of the seed is placed too
deep and a part too shallow. The saving of seed alone in
sowing a large field is often sufficient to practically pay for
a drill. There are certain seeds, however, that must be
covered very shallow, and the modem drill is not well adapted
for the purpose. At one time grass seed was broadcasted
on meadows to thicken the stand, but the drill has been
found to do this work more satisfactorily.

SEEDERS

Hand seeders are used on rough ground where horse
machines can not be used. A very satisfactory type is the
crank machine with a whirling distributor. It is not possible
to secure a very even seeding in
this way, but that is often quite
unavoidable. This type of machine
should have an agitator for feeding

the grain to the distributor. No i

attempt should be made to use the
machine on a windy day. pj^. 133. ^ hand seeder.

Digitized by

Google

224 FARM MACHINERY

The wheelbarrow seeder is preferred by some in sowing
grass seed. At one time the grain seeder lacked refinement
for grass seeding. The wheelbarrow seeder usually has an
agitator feed, which is not accurate, to say the least. This

agitator consists of a
rod beneath the seed
box which stirs the
seed in such a manner

ng. 134. A wheelbarrow seeder. ^ ^ CaUSe it tO floW

out of the opening on
the under side of the box in a fairly uniform stream.

Endgate seeders have one desirable feature, and that
is their great capacity. The seeding, however, is never very
uniform. As far as known, all machines of this class have
whirling distributors, which are either single or duplex. The
latter are claimed to have more capacity and to be more
accurate than the single distributor machines. To improve
their accuracy some makes of
endgate seeders are provided
with a force feed to the dis-
tributor. There is no doubt
that this is a good feature and
should be on all such seed-
ers. Friction and gear drives
are used to drive the distribu-
tor. Spiral gears seem to be

, , . , . I. . , . Fig. 135. An endgate seeder.

tne most satisfactory, but

care should be used in starting the machine so as not to

cause breakage.

Seedbox broadcast seeders are used to a considerable
extent. These are commonly eleven feet wide and mounted
either upon wheels at each end of the box or upon a low wheel
truck underneath. The truck type does not lash the tongue

Digitized by

Google

^■riMsiffin"!

FARM MACHINERY 225

SO much in passing over uneven ground, and for most condi-
tions is to be preferred. The box may be placed low, and
only distributing funnels used to spread the seed, or the box
may be placed higher and the distributing funnels placed at
the lower ends of seed tubes. The latter has not been very
satisfactory, as the tubes are either easily broken or lost.
The seed, of course,
should be released quite
near the ground so as
not be interfered with

by the wind. This type ^^j^. iz^^ a broadcast seedJwith a""
of seeder may have narrow-track truck.

either the agitator feed previously described, or a force
feed. The first type consists of a stirring wheel over an
opening through which the grain is allowed to flow. The
force feed is by far the more accurate, and will be described
under drills.

DRILLS

Furrow-openers. Grain drills are now equipped with
four types of furrow-openers, the single-disk, the double-
disk, the shoe, and the hoe. An idea of the construction of
each may be obtained from the accompanying illustrations.

The single-disk is the best for most conditions. It has
better penetration and will cut through trash better than
any other type. Furthermore, it has only one bearing per
disk to wear out, whereas the double-disk has two. The
single-disk must have one half of the disk turned in the oppo-
site direction from the other half in order to keep the machine
balanced. This is a disadvantage, as it causes the ground
to be left slightly uneven, which necessitates that the drill be
followed with a harrow on rolling ground to prevent soil
washing. The single-disk furrow-opener may be provided

Digitized by

Google

226 AGRICULTURAL ENGINEERING

with a closed boot, which provides a complete passageway
for the seed to the bottom of the furrow independent of the

Pig. 137. A standard single-disk drill at work. This machine has IS
furrow-openers spaced 7 inches apart.

disk; or with the open boot, which depends upon the disk
blade to supply one side of the seed tube. The closed form
is less likely to become clogged, but the open style provides
a slightly wider seed row.

The dovble-disk does not have quite the penetration
that the single-disk has, but when the disks are quite sharp
this type of opener is good for cutting through trash. The
claim is advanced that the principal merit of the double-disk

Fig. 138. Single'disk, double-disk, shoe, and lioe furrow-openers for
grrain drills. The single-disk has a closed boot, or shoe.

Digitized by

Google

FARM MACHINERY 227

lies in the wide furrow that it makes, with a slight ridge in
the center. Definite experiments, as far as known, have not
been conducted to prove any advantage of this kind of
furrow.

The shoe drill has been almost entirely displaced by the
disk drill. It is a lighter draft type, and where penetration
is not desirable it may be the type to select. The hoe drill
has good penetration but can not be used where there is any
trash to contend with.

Force Feeds. Two types of force feeds are used on drills.
The most common is the external feed with a fluted seed

Fig. 139. The external force feed is shown at the left, and the internal
device at the right.

shell. The amount of seeding is varied by slipping the shell
in a guard so as to expose in the seed cups more or less of the
fluted parts as required. The second type is the internal
feed with a ribbed ring to which the seed passes on the inside.
This type does not vary the size of the cells on the ring, but
the feed regulation is obtained by varying the rotative speed
of the ring by a change of gears. Usually two sizes of seed
cells are provided in the ring, one for small seeds and one for
large seeds. The internal feed is the best type for drilling

Digitized by

Google

228 AGRICULTURAL ENGINEERING

large seeds like peas or beans. The cells of the ring, being of
a certain uniform size, will not crush the seed Uke the external
feed. For small grain the external feed, however, is the most
accurate and is the most convenient of adjustment. This
type will drill at a quite uniform rate regardless of the amount
of seed in the seedbox.

Press Drills. The press drill with press wheels to follow
each furrow-opener is the most satisfactory type for fall seed-
ing. The press wheel packs the soil firmly around the seed,
causing the moisture to come up from below by capillary
action and thereby producing early germination. For spring
seeding, when there is an abundance of moisture in the soil,

the press wheel is a dis-
advantage. In regions
where both spring and fall
seeding are practiced, the
press wheel attachment,
which can be used when
desired, is a satisfactory
arrangement.

Selecting a Drill. In
selecting a drill with disk

Fig. 140. A press drill. - j.i_ i_

furrow-openers, the bear-
ings and the means of oiling the bearings should be care-
fully inspected. The bearings are the first parts to wear
out. A good strong frame is important, as well as a
trussed and braced seedbox. The best designs do not
depend upon the seedbox to support the drill, except in a
minor way.

Seed Tubes. Rubber, wire, and steel ribbon seed tubes
are used on drills. The rubber tubes are quite satisfactory,
but are not durable, especially if not well protected from the
weather. Steel wire tubes are satisfactory except when

Digitized by

Google

FARM MACHINERY 229

stretched, when there is no way of shortening the tubes and
filUng the cracks. The steel ribbon is no doubt the best of
all, as it is affected only by rust.

Adjustment. The furrow-openers
should have a convenient means of ad-
justing the spacing. A double drag-bar
is without doubt preferable to the single
one. The common spacings of furrow-
openers are six, seven, and eight inches.
For the average conditions, seven inches is
a very satisfactory spacing. Seven-inch
drills are usually made with 12 or 18 fur-
row-openers. The latter is a good size
suitable for foiu* horses, and will cover
three com rows of 3 J^ feet each.

Horse Lift. The horse hft for large
drills is a great convenience. To be com-
plete, the drill should have a grass seed Fig. i4i. a section

, , , , .... A J. 1 ot the seed box of

attacnment, permittmg grass seed to be a arm showing loca-
drilled with other crops. The footboard box and^l^s^t^el Hb-
is preferred by some to a seat. This is **°" *"^®*
a matter largely of personal preference, but the footboard
permits the driver to shift from one side to the other
to manage the driving better. A double capacity or auxiUary
seedbox may now be had with many drills. This obviates
the necessity of filling the seedbox so often.

QUESTIONS

1. What advanjtage has the grain drill over the seeder?

2. Describe the use and construction of hand and wheelbarrow
seeders.

3. How is the grain distributed with the endgate seeder?

4. Describe the various methods of constructing the seed-box
broadcast seeder.

Digitized by

Google

230 AGRICULTURAL ENGINEERING

5. What two types <rf feed are used in broadcast seeders?

6. Describe the constructicm and the relative merits of the various
types of furrow-openers used on grain drills.

7. Describe two types of force feed for drills.

8. For what conditions is the press drill adapted?

9. What are the important features to be considered in the selecticm
of a drill?

10. Of what material are the seed tubes made?

11. What is the conmion spacing of furrow-openers? .

12. What is a horse lift for a drill?

Digitized by

Google

CHAPTER XXXV
CORN PLANTERS

Essentials of a Com Planter. The modem com planter
is a highly-developed implement and well able to meet
the exacting demands made upon it. A good planter will
fill the following conditions:

Krst, a com planter is expected to place in every hill a
certain number of kernels of com.

Second, the com must be placed at a uniform depth,
regardless of the condition of the soil or trash that may inter-
fere.

Third, the check-rower must place the com accurately
in rows for cross cultivation.

Fourth, the planter must be convenient to operate.

fifth, the planter must be capable of adjustment to the
planting of cane, beans, and several of the other crops grown
on the general farm.

No doubt accuracy is the first requisite of the modem
planter. In selecting a planter, therefore, the dropping
mechanism should be given first consideration.

The Dropping Mechanism. There are two distinct
types of dropping mechanism upon the market, the full-hill
drop and the accumulative drop. In the fvU-hill drop a seed
cell is provided large enough to contain the desired number
of kernels for one hill (as three, for instance). These three
kernels are all counted out at one time, and if they should
be slightly imdersized it would be easy for a fourth to sUp
in as the seed plate containing the seed cell passed under the
seedbox.

231

Digitized by

Google

232 AGRICULTURAL ENGINEERING

The accumulative drop, on the other hand, provides seed
ceUs in the seed plate large enough to contain only one kernel
at a time. The hill is formed by receiving in a receptacle
the desired number of kernels from as many cells. The
accmnulative drop would appear at once to be the more

FIgr. 142. A modern corn planter with long shoe furrow -openers, vari-
able drop, and open wheels.

accurate of the two types, and it may be demonstrated that
it is, when seed com graded to size is used. As the cell in
the accumulative drop is made to contain one kernel only,
it is evident that great care must be used in making the cell,
and even then there will be difficulty in caring for odd-shaped
kernels whose volmne may not be much different from the
average. These ill-shaped kernels are those from the butts
and tips of the ears, and when an accumulative drop planter
is used they must be discarded.

Digitized by

Google

FARM MACHINERY 233

The edge-selection drop, now quite generally used by-
manufacturers, is an accumulative drop with the cells in the
seed plate constructed deep and narrow to receive the kernel
on the edge instead of on the flat, as ar-
ranged for in the so-called flat plate.
The edge-selection plate provides very
deep seed cells from which there is little ^^^ ^^^ ^^^ ^^^^
possibility of the corn's being dislodged eeiection and round-

r 1 «. 1 . 1 1 11 ^<*^® ^^^^ plates.

by the cut-oflt which covers the cell as
it passes over the receiving receptacle. There is danger,
however, of the kemePs becoming damaged by being caught
in the cell on end in such a way that the cut-off cuts the kernel
in two.

Graded Seed. The planter will do more accurate work
if provided with carefully graded com, and this fact should
never be overlooked. After removing the butts and tips,
the com should be run through a good com grader, and
then there should be a careful selection of plates to suit the
com to be planted. Different varieties of com and com
from different localities differ much in size and shape, and
accuracy of drop can only be secured when the plates are
carefully selected for the com at hand. Sometimes the
proper plates are not furnished with the planter, and new
plates better suited for the com at hand must be secured
from the manufacturer. There are usually three sizes of
plates fiuTiished with each planter, and these will accommo-
date nearly all of the variations.

The variable drop mechanism is of recent origin. By its
use the seed plate is made to count out from two to four ker-
nels by simply shifting a lever to the designated notch. This
device can be used to best advantage in hilly fields where
the fertility of the soil varies much, enabling fewer kernels
to be planted in the hills where the soil is thin.

Digitized by

Google

234 AGRICULTURAL ENGINEERING

It also dispenses with many of the plates which must be
furnished with a planter that does not have the device.
Furrow-openers. The long shoe furrow-opener is in

more general use than any
other type. It has good
penetration and is easy to
guide. Where there is
trash in the way, the stub
runner, which hooks un-
der the trash, should be
I used. The single-disk
furrow-opener has good
penetration and should be
used in soil that often
becomes very compact

nsr. 144. A corn planter with stub shoe bcforC thc COm Can bc
furrow -openers. i ▼ . . •

planted. It is quite im-
possible to make perfectly straight rows with the disk
planter. The bearings of the disks are subject to wear, and
the single disk throws the
earth to one side in open-
ing the furrow, making
the covering difficult. The
double-disk furrow-opener
offers additional compU-
cations without material
advantages. It is some-
times maintained that the

disk planter is of lighter rig. 145. a com planter with disk Mr-
draft. Even if this be row-openers.

true, the planter under any circumstances is not a heavy
draft implement.

Wheels. The accepted type of wheel for com planters

Digitized by

Google

FARM MACHINERY 236*

is the open wheel. The wheel is depended upon to cover
the com and pack the soil over it. To do this, the open
wheel not only offers an improvement over the flat or concave
wheels, but is much easier to keep clean. The open wheel
has two tires about one and one-half inches wide and set
about two inches apart. These two tires are so set as to
draw the soil together over the furrow made by the furrow-
opener.

The double-wheel type has two wheels to follow each
furrow-opener. These wheels
are capable of being adjusted
so as to draw the earth over
the furrow as desired. Com
planter wheels are made in
various heights to accommodate
the machine to the varying

conditions as they may arise, pig. i46. The open and double
Thus, in certain sections, the *^p^ "' '^'''^ ^'^^^'^^ ^'^''''•
com is planted in furrows made by the lister, and, to span the
high ridges between the^ furrows, very high wheels are
necessary.

Conveniences. There are many devices to be found on
the modem planters which are designed to save time. The tip-
over seedbox is one. Thus, if it is desired to change the seed
in a seedbox for any reason, it is not necessary to pick out
the seed com kernel by kernel. A reel on which to wind
the check wire as the last row is planted is another convenient
device. There are two general forms of reels in use; one is
hung under the seat, and the other is placed on a bracket
over the planter wheel at either side. The first location is
the most convenient when preparing to reel the wire; but the
side location permits the wire to be reeled as the last row is
planted, the reeling being in plain sight of the driver and

Digitized by

Google

236 AGRICULTURAL ENGINEERING

there is no necessity of crossing the wire with the team.
Some friction device must be used to drive the reel.

The double marker, or a separate marker for each side
and which may be raised to a vertical position when not in
use, is undoubtedly the most convenient marker. There
is less time consumed in putting it in use and there is no
crossing of the lines with the draw rope. Where the soil is
hard the disk marker should be used in preference to the
drag head marker.

Adjustment. In addition to a selection of the proper
seed plate, or calibration of the planter, as it is sometimes
called, the machine should be kept in proper adjustment and
good working condition when in the field. One of the more
usual neglects of this kind is the failure to keep the planter
"front," the part of frame which supports the runners,
level. If the front be tipped back or forward, the com will
be deposited in hills back or ahead of its proper location and
will not form perfect rows crosswise.

QUESTIONS

1. What are the essentials of a good com planter?

2. What is the difference between the "full hill" and the accumula-
tive drop?

3. Why is it important to have graded seed?

4. What is the variable drop?

5. Describe the various styles of furrow-openers used on com
planters, and give their merits.

6. What types of wheels are used?

7. What are some of the conveniences used on modem planters?

8. How should planters be adjusted for accurate check-rowing?

Digitized by

Google

CHAPTER XXXVI
CULTIVATORS

Development. The development of the com cultivator
exemplifies and t3rpifies the development of agricultural
methods'during the past century. Originally com, or maize,
to be more accurate, was planted and cultivated almost
entirely with the hoe. Later, the single- or double-shovel
cultivator was introduced to assist the hoe. Still later the
straddle or single-row cultivator was developed. At the
present time the double-row cultivator is tjrpical of modem
methods. The single- and double-shovel cultivators have
been discarded from field operations, 'and only the single-
and double-row cultivators are left.

Selection of a Cultivator, Whether or not the double-row
cultivator can be made to do the same quality of work with
greater economy than the single-row is a question that many
farmers are trying to decide. The solution of this problem
will depend largely upon local conditions. It is unquestion-
ably true, however, that the successful use of the two-row
cultivator depends upon careful farming at all times in pre-
paring the ground and in planting and tending the crops.
The two-row cultivator is not an implement well designed
to select and destroy individual weeds, nor is it capable of
being adjusted to cultivate each hill of com, regardless of
whether or not that hill may be in a straight row. The two-
row cultivator is used successfully where good farming sup-
plies fields comparatively free from weeds, well-prepared
seed beds, and straight com rows. If this high-class farming
is practiced, the two-row cultivator will be found a necessary

237

Digitized by

Google

238 AGRICULTURAL ENGINEERING

part of the equipment of the modem com grower. The use
of the two-row cultivator is a question upon which opinions
of some of the best farmers differ. This indicates that, in
addition to the necessary field conditions mentioned, the
personal factor is one that makes for success or failure.

Walking Cultivators. The walking cultivator is made
both with and without a tongue. The advantages of the

tongueless kind are that
they are light and re-
quire less turning room
than the other. The
difference in cost is small.
On the other hand, the

FIgr. 147. A tongueless walking culti- tOUgUeleSS CUltivatOr
vator with wooden gangs. n i

works very well only
with a well broken "and evenly-gaited team.

Cultivator Construction. As one- and two-row cultivators
have many features in common, they will be discussed to-
gether. Perhaps the most important feature to be decided
upon in the selection of a cultivator is the shovel equipment.
Shovel cultivators are provided with from four to eight
shovels for each two gangs. By gang is meant the
beam, the shanks, and the shovels attached thereto. The
four-shovel cultivator is adapted to deep cultivation;
the six and eight to more shallow cultivation, covering the
space between the rows more thoroughly but less deeply.
With a large number of shovels and shanks, the gangs
become easily clogged with trash if the ground is not entirely
free from it. A compromise is represented by the six-shovel
cultivator, which is the most popular throughout the com
belt.

The cultivator beams are now quite generally made of
steel, although wooden beams may be purchased. Although

Digitized by

Google

FARM MACHINERY 239

slightly heavier, the steel beam is not so easily clogged with
trash. The shanks may also be of steel or wood, with the
same advantages. A break-pin device or a spring trip
should be provided to prevent breakage of the shank if a
root or stone be struck by the shovels. The best cultivator
shovels are made of soft-center steel hardened so as to
take a bright polish.

The widths of the shovels vary from two to four inches,
and the wider shovels may be twisted so as to assist in throw-
ing the furrow to one side. The straight shovels are adjust-
able upon their shanks to accomplish the same results.
Where shallow cultivation is desired without a surface culti-
vator, the spring-tooth cultivator, with four to eight small
teeth mounted upon springs, is successfully used.

The coupling of the beam to the frame is one of the most
important features of the cultivator, for it must enable the
beam to be shifted horizontally and vertically and at the
same time cause the
shovels to remain in a
vertical position. In
order that this part of
the cultivator shall ren-
der long service, due
provision must be
made for adjustment
for wear.

The gangs should

i_ J J xi_ X Fig. 148. A riding cultivator with balance

be SO SUSpenaea tnat frame and hammock seat.

they will swing in a

horizontal plane and not be Ufted from the groimd when
swung to one side. Since there is a tendency to advance
the shovels as they are swung to either side, it is easy to see
why a long beam is more easily guided than a short one.

Digitized by

Google

240 AGRICULTURAL ENGINEERING

As the long beam is swung to one side it does not advance
so much, because it travels in the arc of a larger circle.

Due provision should be made for varying the width
between the gangs to suit the various conditions which may
arise. This adjustment should be easily and quickly accom-
pUshed, The wheels should also be adjustable to various
widths. Many cultivators are now made with reversible
axles; that is, the axles are made in the form of the letter Z;
one of the two ends, which are alike, is attached to the culti-
vator and the other end serves as the axle proper. After
the one becomes worn, the ends may be reversed and a new
wearing surface presented.

Wheels. The wheels of a cultivator should be high and
have wide tires which will not carry dirt up on the inside.
Often the value of a cultivator is indicated by the construc-
tion of the wheels. To determine their strength, the width
and thickness of the tires and the number and diameter
of the spokes should be observed. The wheels should have
interchangeable boxes which may be replaced after they are
worn without requiring an entirely new wheel, and these
boxes should be dustproof or long distance. To describe,
the wheel is held in place by a collar on the inside arranged
to exclude the dirt and dust, and the outer end of the wheel
box is enclosed. The end of the wheel box had best be remov-
able for filling with axle grease or hard oil. A supply of
grease in one of these inclosed boxes will last for a long time.

Balance Frame. The balance frame now generally used
on cultivators has two purposes; first to balance the weight
of the operator on the wheels; and, second, to balance the
cultivator when the gangs are carried out of the groimd.
The balance frame makes provision for setting the wheels
forward or backward as required. It should be a feature
of every riding cultivator.

Digitized by

Google

FARM MACHINERY 241

Guiding Devices. To guide or steer cultivators, the
tongue or the wheels are often pivoted and connected to
levers in such a way as to be conveniently operated.
The pivoted tongue enables the operator to vary the angle
with which the tongue is attached to the cultivator. The
tongue may be attached to a treadle to be worked by the feet
and used continually for
guiding the cultivator, or
it may be attached to a
lever, permitting adjust-
ment for hillsides or for j
the team when they can- '
not be driven true to
the row.

-, £ » j7 FJff. 149. A two-row cultivator with

bome form of treoule straddle seat placed well to the rear. The
. , . , -It gangs are guided by a treadle device.

guide must be provided

with the two-row cultivators, as it is not possible to guide
each pair of gangs independently. The treadle guide may be
attached to the gangs only, or it may govern the direction of
wheels at the same time. It is claimed that this double
arrangement requires less effort on the part of the operator,
for it is only necessary to change the direction of the wheels
and the team must do the work. On the other hand, the
shifting of the gangs alone gives a much quicker action.

Seats. The seat of the riding cultivator is made in two
forms, the straddle seat and the hammock seat. The first
is placed upon a. stiff arm extending back from the frame,
and the second has the seat suspended on a metal strap be-
tween two arms extending back from the frame. The stradle
seat is more rigid and is universally used on lever and treadle-
guided cultivators. The hammock seat offers a good oppor-
tunity to operate the gangs with the feet, as the seat support
is not in the way.

Digitized by

Google

24S AGRICULTURAL SNQINEERING

Smftwe Cuttmitors. The surface cultiYalor is apparently
gaining favor throughout the com belt. It is provided with

kmg flat shovels which shave
the ground from one to two
inches bdow the surface, cut-
ting off the weeds and pulver-
iiing the surface. The sur-
face cultivator is a special
implement. It has been the
author's experience that go-
pher or surface shovels at-
tached to the shovel cultivator

Fi». 150. A surface cultivator. ^^j^ ^ ^^^^ ^j^ j^^^^^ ^

anything but satisfactory. It is quite necessary that the
gangs be of very rigid construction or the shovels will not
run at an even depth and will not be easily controlled.
The surface cultivator
will work satisfactorily
only where the ground is
in good tilth and free
from trash.

The Disk Cultivator.
The disk cultivator is
preferred by some com
growers. It is generally
used in connection with

the weeder or for listed ^^^ ,,,^ ^ ^^^ ^^^^^^^^^

com, as it moves consid-
erable soil in one .direction, either to or from the com.
Strength and durability of the parts, especially the bear-
ings, are the important things to consider when making
a selection.

Diqitized by

Google

FARM MACHINERY 243

QUESTIONS

1. Trace the development of the cultivator.

2. What are some of the factors which should be considered in mak-
ing a selection of a cultivator?

3. What direct and indirect advantages has the riding cultivator
over the walking cultivator?

4. Describe the construction of the tongueless walking cultivator.

5. Describe some of the important features of modem cultivators.

6. What can you say of the various shovel equipments for culti-
vators?

7. Describe a good method of suspending the gangs.

8. What adjustment should be provided in the cultivator?

9. What is the purpose of the balance frame?

10. What is the difference between a pivoted tongue and pivoted
wheels?

11. What two tjrpes of seats are used on cultivators?

12. Describe the construction of the surface cultivator.

13. To what use may the disk cultivator be put?

Digitized by

Google

CHAPTER XXXVII
THE GRAIN BINDER OR HARVESTER

Of all the machines which have been invented and de-
veloped during the past century, perhaps none has been the
means of saving more labor than the modem grain binder.
It has been the main factor in reducing the amount of labor
required to produce a bushel of wheat from three hours to
ten minutes, and at the same time has greatly improved the
quaUty of the product.

The grain binder has undergone little change in the last
ten years, nor is there any important improvement proposed
or desired at the present time. The test of time has elimi-
nated from the field the unsatisfactory machines, in spite of
the fact that the binder is a very complicated machine and
must often do its work imder very adverse circumstances.
For these reasons this chapter will be a discussion primarily
of the adjustments of the binder.

Size. Formerly the standard binder was a 5-, 6-, or 7-foot
cut machine. More recently, by the use of tongue trucks
to care for the side draft, the 8-foot machine has become
popular among farmers who have large areas of grain to cut.
Under favorable conditions and with large areas the push
binder of 10-, 12-, or 14-foot cut may be used economically.
These machines require at least six horses, and four horses
are generally used on the eight-foot-cut machines.

Selection. Convenience and proper range of adjust-
ment, and adequate means of lubrication are the important
things to keep in mind in selecting a binder. The variety
of grains harvested with the grain binder requires a wide range
of adjustment.

244

Digitized by

Google

FARM MACHINERY 245

Digitized by

Google

246 AGRICULTURAL ENGINEERING

Tongue Trucks. The tongue truck is one of the newer
attachments for the binder, and is a device which is highly
satisfactory, especially on the wide-cut machines. It is
quite impossible with these wide machines to arrange the,
hitch in such a way as to overcome side draft. The tongue
truck is the only satisfactory method of relieving the horses
of this burden.

Engine Drive. It has become a quite common practice
of late to moimt a small gasoline engine upon the binder to
drive the machinery, relieving the horses of all work except

Fier. 153. The harvester shown in Fier. 152, with some of the parts

named.

that required in drawing the machine on its wheels. This
makes it possible to save a crop on wet, soft groimd where
an ordinary binder would fail because the main wheel will
slip. In extreme cases the binder has been successfully
mounted upon skids or sled runners and used to save a crop
where the soil was so wet and sticky that the main wheel of
the binder would become so thoroughly filled with mud as
to refuse to revolve.

Operation of Binders. It should be the pride of every
binder operator to so manage and adjust his machine that

Digitized by

Google

FARM MACHINERY 247

perfect, well-bound bundles will be formed and tied. To
procure such bundles, attention must first be given to the
adjustment of the reel, which should so catch and deliver
the standing grain that it will fall evenly and squarely upon
the platform apron or canvas. If the grain is straight and
standing well, the reel should be set far enough ahead and
low enough that the grain will be sUghtly bent back over the
platform when cut off. This will cause it to fall directly
back at right angles to the cutter bar. Often the grain varies
in height in different parts of the field, and adjustment of
the reel should be made from time to time while the machine
is in motion.

Again, the proper adjustment of the binder attachment
and the butt adjuster canvas should not be overlooked.
In all machines these two parts are adjustable. The binder
attachment may be sUd forward and backward, enabhng
the operator to place the band nearer the head or the butt of
the bundles as he may desire. In like manner, the butt ad-
juster may be set so as to push or pat the straw into an even
bundle at the butt end and to push the straw back more or
less as desired.

Sometimes a binder will give trouble in tearing the slats
from the canvas. This trouWe is due to the fact that the
rollers over which canvases pass are not parallel or square
with the frame. If trouble of this kind occurs, the elevator
frames and rollers should be immediately trued up. Pro-
vision for adjustment is found on all machines, and the car-
penter's square will be foimd a useful means of securing
accuracy.

The main drive chain of a binder, if run tono loosely and if
dry or muddy, has a tendency to climb the sprocket teeth and,
in slipping in place again, give the machine a jerky motion
as if some part of the machine were catching or striking some

Digitized by

Google

248 AGRICULTURAL ENCflNEERING

other part. This action makes the difficulty hard to locate.
It is easy to overcome by simply tightening the chain and by
oiling.

The elevator chain, the long chain which drives the ele-
vator rollers, should not be run too tight, as it increases
the draft and the wear of the parts. Machines are some-
times greatly damaged in a short time by nmning this chain
too tight.

Adjustment. To make bundles of the proper size, the
binder is provided with a clutch which is placed in gear by
the trip when sufficient grain has been gathered by the
packers to form a bundle. If the spring which holds the
clutch pawl, or dog, in place be lost or broken, the clutch will
not be positive in its action and will form undersized bundles.
If larger or smaller bundles are desired, the bundle-sizer
spring should be adjusted, and not the compress spring or
the spring connected with the needle shaft. The latter spring
is used to relieve the strain upon the parts, and should not be
made too tight.

Causes of Failure to Tie. The part of the binder which
requires the most careful adjustment is the tying mechanism.
Mention can only be made here of a few misadjustments and
their symptoms. It is
customary for those who
practice binder experting
to examine the band that
comes from the machine

when the machine fails , ^ _

to tie. Often the ends „ > „, N ^. w

Knotter. Stripper Twine disk

of the twine, whether Fig. 154. The tying mechanism of a
- , i «• 1 modern binder.

frayed or cut off clean,

the kinks in the twine, or the knot, if there should be one

in one end of the band, will indicate at once the cause of

Digitized by

Google

FARM MACHINERY 249

the failure to make a complete knot. The names of the
various parts of the tying mechanism may be learned from
the accompanying illustration. If the needle does not carry
the twine over far enough, the twine disk, or cord holder,
will grasp only one strand, and the knot will be tied only

in one end of the cord,
with the other extending
back to the machine.
This condition is shown
in No. 1, Fig. 155, and
may be caused occasion-
ally by a straw interfer-
ing with the placing of
the twine.

When the twine disk
is too tight, the symp-
toms will be much like
those just described, ex-
cept that one end of the
band will be frayed (No.
* ^^ " -^^^ 2,) indicating thatifc has

Fig. 155. The ends of bands which have Vn^-_ _ x -ly Vn U *
not been made into perfect Icnots. (After DCCn CUIi OU Dy DCmg
steward in Trans. Am. Soc. A. E.> pinchcd tOO tightly and

that the spring should be loosened. If both ends are cut
off irregularly, as shown in No. 3, it is quite a sure sign
that the holder is too tight.

If the knotter spring, which holds the finger down upon the
knotter hook, is too loose and does not hold the ends of
the twine while the knot is pulled over the hook forming the
knot, the ends of the band will appear as shown in No. 4.
The same kind of band is found when the knife cuts
the twine too soon before the knotter finger has closed
over it.

Digitized by

Google

250 ACFRICULTURAL ENGINEERING

If the needle has become bent or the pitman which
actuates it worn mitil the needle does not place the twine
squarely over the notch in the twine holder, a loose band
will be produced as shown in No. 5, Fig. 155; that is, there
will be a knot in one end, and the other end will be cut off
squarely but without a kink in it.

If the needle of the modern binder becomes sUghtly
bent, it may be hanmiered back without fear of breakage.

QUESTIONS

1. Why is the grain binder an important machine?

2. In what sizes are grain binders manufactured?

3. What are the important features involved in the selection of the
grain binder?

4. To what use may the tongue truck be put?

6. When may the machinery of the harvester be driven with a
gasoline engine to good advantage?

6. To what purpose should the binding mechanism of the harvester
be adjusted?

7. How should the elevator rollers, main and elevator chains be
adjusted on a binder?

8. What adjustment should be made to change the size of the
bundles?

9. Explain five causes for failure of the knotter to tie a knot.

Digitized by

Google

CHAPTER XXXVIII
CORN HARVESTING MACHINES

Sled Com Cutter. These machines are arranged with
stationary knives set at an angle on the edge of a platform
and at such a height that the standing stalks will be cut off
as they are grasped in the arms of the operator standing
or sitting upon the platform. The machine is moimted
either upon sled runners or upon low wheels and is drawn
by one or two horses. When an armful of stalks has been
collected^ a stop is made and the com laid in piles or is
shocked at once. These sled cutters are often homemade
and are constmcted in a variety of shapes and forms.

Several machines have been devised with arms and other
mechanism to assist in gathering the stalks; but these ma-
chines, although quite successful, have not come into extend-
ed use, owing perhaps to
the fact that, if a more
expensive machine were
desired than the simple
sled harvester, the com
binder would be pur-
chased.

Fig. 166. A sled corn harvester.

It has been found
that the average acreage harvested in a day by two men
and one horse with a sled harvester was 4.67 acres, the
amount ranging from 2 to 10 acres. This variation is un-
doubtedly due largely to the weight and condition of the com.
The sled harvester cannot be used successfully in extremely
heavy corn or in com which does not stand upright.

251 /

Digitized by

Google

252 AGRICULTURAL ENGINEERING

The Com Binder or Harvester. Because of the general
introduction of the silo, the com binder is used more than
ever before. In filling the silo the com must be cut rapidly,
and besides it is much more conveniently handled when
bound into bundles. When the com is shocked, the use of
the harvester will not show much economy over cutting by
hand; this, however, is disagreeable work, and the use of the

Fig. 157. A corn harvester of the vertical type at work.

machine is to be commended because it does away with
much of it.

Resultsofaninvestigationof comharvestingmethods*show
that the average acreage cut per day with a binder was 7.73
acres. The average life of the com harvester was 8.17 years,
cutting on an average a total of 668.77 acres. The amount
of twine used per acre was 2.44 pounds, and one man was
able to shock the corn on 3.31 acres in one day. . From this

♦Farmer's Bulletin 303, U. S. Dept. of Agriculture.

Digitized by

Google

FARM MACHINERY 253

data the cost of harvesting and shocking an acre is made up
in the following items:

Cost of machine and interest on investment . . . $.29 per acre

Driver and team 46 per acre

Twine 305 per acre

Shocking 448 per acre

Total cost $1,503 per acre

If a large acreage is hairested annually, the cost per acre
will be much reduced. In modern siloing operations the
com is loaded directly upon wagons, and the cost of shock-
ing, which is about one-third of the cost as given above, is
not incurred.

Types of Com Binders. There are two general types
of com binders upon the market: those which bind the corn
in an upright position, and those which convey the cut corn
to a horizontal deck before binding. There is also an inter-
mediate type in which the com is neither vertical nor hori-
zontal, but somewhere between the two, or inclined. Each
of these types is well
tried out and is success-
ful, and they differ but
little in the essentials of
construction. Dividers
on either side of the row

gather and lift the down Fig. 158. a com harvester of the
stalks. Chains with lugs horizontal type.

extending across the opening between the dividers carry
the stalks back to the binder proper. There are usually
three pairs of these conveyor chains, one pair for the butts,
one pair of main chains, and one pair for tall com.

At least one machine does not have the usual packer
found on the others and on the grain binder. In this machine

Digitized by

Google

254 . AGRICULTURAL ENGINEERING

the conveyor chains are made to extend farther back, and
during the time a bmidle is being tied the lugs or fingers are
allowed to fold back, not forcing the com upon the needle.
Three horses are usually used with the com binder, though
in heavy com four horses, two teams in tandem, can be used
to good advantage, and the extra power is much needed.

The care and operation of the com binder do not differ
materially from that of the grain binder. The adjustment
of the tying mechanism is just the same. The service
demanded of the com binder, however, is much more severe,
and it does not have as long a Ufe as the grain binder.

The Com Shocker. The com shocker is an implement
with cutting mechanism very similar to that of the com
binder, but a roimd, horizontal platform with a center pole
is provided, and is made to revolve and collect the cut com
and form it into a shock. When a shock is formed, the ma-
chine is stopped and the shock tied and then Ufted from the
platform and swung to the ground by means of a derrick and
windlass. The fingers which extend out from the center
pole are then allowed to drop, and the center pole is removed
and returned to the machine.

This machine has only about one-half the capacity of the
com binder, as much time is consimied in removing the
shocks. Other disadvantages are, first, the shocks are small
and do not stand well; and second, the fodder is not as con-
venient to handle as when bound into bundles. In favor of
it, it must be mentioned that it is a one-man machine, and
there is a saving in the cost of twine.

Com Pickers. The successful com picker is one of the
most recent of agricultural machines, although inventors
have been trying to invent a machine for field picking for
nearly two-thirds of a century. The mechanical difficulties
tx> be overcome and the lack of an imperative need for the

Digitized by

Google

FARM MACHINERY 256

machine are the main reasons why this machine has not been
perfected to the extent that it could be manufactured and
sold in the usual way.

Construction. As usually constructed, the com picker,
sometimes called the com picker-husker, has dividers which
straddle a row of standing stalks and gather them into an
upright position similar to the action of a com harvester.
Then the stalks are run through rollers set at an incUne and
provided with spirals in such a way that the stalks are con-
veyed back as fast as the machine is moved forward. These
rollers pinch off the ears, which fall into a conveyor at one -

Fig. 159. A corn picker-husker at work.

side of the rollers and are carried to the husking rolls. These
rolls revolve in pairs, and, by means of steel studs or husking,
pins set in the rolls, grasp the husks and pull them from the
ears. The husked ears and the shelled com are then
elevated into a wagon drawn beside the machine. The
better machines have a fan for blowing out the chaflF and
husks and saving all of the com.

The com picker-husker is one of the heaviest of field
machines, and under average conditions requires five large
or six mediiun-large draft horses to draw it. A driver is
required, and two men or boys with teams and wagons are

Digitized by

Google

256 AGRICULTURAL ENGINEERING

aeeded to haul away the com as it is gathered and husked.
An elevator for unloading the com is quite an essential part
of the complete outfit.

There is naturally much difference of opinion in regard
to the economy in the use of the com picker-husker over
hand picking. It is to be recognized that conditions vary
greatly, and it is upon local conditions that its success will

Fig. 160. A corn husker and shredder at work.

. depend. The machine, on account of its great weight, can-
not well be used when the soil is wet. Again, the machine
does not do its best work in com that is lodged badly. It
will not pick up any ears not attached to the stalks.

Com Huskers and Shredders. In many localities the
husker and shredder is quite a popular machine, and it is
right that it should be. As farming advances, methods
utilizing the entire com plant are sure to become more general.

The modem husker and shredder consists in snapping
roils to remove the ears from the fodder as it is fed to the

Digitized by

Google

FARM MACHINERY 25V

machine, a shredder head to reduce the fodder to fine pala-
table stock feed, husking rolls to remove the husks from the
ears, an elevator to elevate the husked com into a wagon,
and an elevator or blower to convey the shredded fodder

Fig. 161. A section of a corn hunker and shredder.

away from the machine. Most machines have devices for
saving the shelled com. Some of the larger machines have
band cutters and self-feeders.

The size of the husker is designated by the number of
rolls. An eight-roll husker will husk from 25 to 80 bushels
of com per hour, and require from 16 to 20 horsepower. The
cost of shredding varies from $2.50 to $6 per acre.
QUESTIONS

1. Describe the sled com harvester. Is it practical?

2. What are the principal items and the amount of each in the
cost of harvesting com with the com harvester?

3. Describe the two general types of com harvester.

4. Describe the construction of the com shocker.

5. Describe the constmction of the com picker-husker.

6. Where may the picker-husker be used to the best advantage?

7. What can you say of the economy of the husker and shredder?

8. Describe the construction of the com husker and shredder.

9. How are the sizes of huskers and shredders designated, and
what is the capacity of the various sizes?

Digitized by

Google

CHAPTER XXXIX

HAT-MAK[NG MACHINERT
MOWERS

The modem mower has become a standard machine, and
the various makes differ in details only. Inventors have
devised many styles of cutting machines, but all have given
way to the reciprocating knife which acts between guards or
fingers, giving a shear cut.

Types. The center draft mower, with the cutting bar
directly behind the team and in front of the driving wheels,
is manufactured in a limited way. The main advantage of
this type of machine seems to be that the team does not walk
over the new-mown grass and tramp it into the stubble
This advantage is offset by the convenience of the side cut
machine, the type in general use.

Size. Mowing machines may be secured in almost any
size from the one-horse mower of 33^ or 4-foot cut to the
8-foot-cut machine. The 43^ and 5-foot cuts are known as
the standard machines, and the 6-foot cut as the standard
wide-cut machine. The wide-cut machine is usually made
somewhat heavier than the standard machines, yet they are
adapted only to certain conditions where the service consists
largely in straight meadow mowing.

Construction of Mowers. The weight of a mower
determines to some extent its driving power, but this is also
increased by the design of the wheels and the distribution
of the weight. The drive wheels should be high and have
broad tires. The usual widths of tires are 33^ and 4 inches.

258

Digitized by

Google

FARM MACHINERY 259

It is best that the wheels be placed far apart, as this makes
a better balanced machine as far as draft and driving power
are concerned.

The main shaft should be a smooth or "cold rolled" shaft
throughout its entire length, and should be of liberal size.
Roller bearings for the main shaft are desirable, as they not
only reduce friction but also prevent any binding of the shaft
in the frame and fiunish a good reservoir for a supply of oil.
It is well that the wheels be provided with a suflScient number
of pawls to engage the axle ratchets without much lost
motion. There should be little lost motion throughout
the entire mechanism, as it is highly desirable to have the
knife start as soon as the drivers and prevent the guards from
becoming clogged.

There is at the present time a considerable difference in
the size of the gears used in mowers. Besides being strong

FIgr. 162. A modern mower at work.

Digitized by

Google

260 - AGRICULTURAL ENGINEERING

enough, these gears should be of liberal dimensions, especially
in width, to resist wear. It is an advantage to have the gears
so arranged that the thrust which exists between separate
pairs of gears shall balance as far as possible.

Due provision should be made to keep the gears well
lubricated and well protected from dust. There is no good
reason why the gears of mowers should not be arranged to
run in oil, although this is not practiced.

The small, fast-moving gear pinion is the first to wear
out, and the construction of the mower should be such as
to permit this pinion to be easily replaced. There is con-
siderable end thrust on the crank shaft upon which the bevel
gear pinion is placed, owing to the tendency for the gears to
force themselves apart. This end thrust should be carefully
provided for. Some of the best mowers upon the market
are made with a ball-thrust bearing. Other mowers have
hardened steel washers to take the wear, and in any case
there should be means of adjusting for wear.

The chain drive mower is used to some extent at the pres-
ent time, but not as much as formerly. There are at least
two disadvantages of the chain-drive mower, in which one
pair of gears is replaced by a pair of sprokets and a chain or
Unk belt; first, it is not as positive in action as the gears; and,
second, the chains do not seem to be as durable as the gears.

Usually mowers have but two pairs of gears, but some
mowers have three. No serious objections can be made to
the latter. At least one make has two speeds for the knife,
obtained by changing gears. The lower crank end of the
crank shaft should have a bearing which will permit adjust-
ment for wear. One of the most common methods of mak-
ing this adjustment is to replace an interchangeable brass
bush used as the bearing lining. In mowers there is an
adjustable cap to the bearing, which may be adjusted by

Digitized by

Google

FARM MACHINERY 261

means of the bolts which hold it in place and by the use of
liners under the edges of the cap.

It is to be expected that the severest wear will come upon
the pitman. The pitman bearings are diflBicult to lubricate.
A mower which does not provide for adjustment and replace-
ment of the wearing parts of the pitman and crank is not
modem. Owing to the difficulty of keeping adjustable parts
tight, the crank pin box is usually made of soHd metal, lined
with brass or babbitt, and capable of being replaced at small
expense.

Provision is made in every modem mower for the replace-
ment of the wearing parts of the cutting mechanism and for
their adjustment to the fullest extent. This statement refers
to the sickle or the sec-
tions of it; the guards or
their ledger plates, which
provide one-half of the
cutting edges; the cUps
which hold the knife ^
over the ledger plates;

and the wearing plates ''*^- ^''' ^ ^*^^-^^"" ™°"^"
which support the rear edge of the sickle. All of these
parts are subject to rapid wear, and even when made of the
best materials they must be replaced several times during
the life of the mower. It is not an uncommon matter to
find that a mower has been discarded when it could be made
practically as good as new by the replacement of parts whose
cost is but a small part of the whole.

The cutter bar of a mower should be carried as far as pos-
sible upon the main truck, in order to reduce the draft due
to dragging the bar. This is usually accompUshed by suit-
able Unkage and springs which may be adjusted in such a
manner as to carry all of the weight, except enough to keep

Digitized by

Google

262 AGRICULTURAL ENGINEERING

the cutter bar to the surface of the ground. A draft rod
direct from the doubletrees to the cutter bar assists in lower-
ing the draft, and is universally used on modem mowers.
Adjustments of the Mower. The adjustments of the
mower are of the greatest importance. First, the cutter bar
should be in aUgnment, or should extend out to the side of
the mower at right angles to the crank shaft. If not in per-
fect alignment, the pitman will be cramped, increasing the
wear, if not causing early breakage. There is sure to be
more or less wear in the hinge joints of the cutter bar, and

Fig. 164. An illustration showing the proper adjustment of the
cutter bar.

an adjustment must be made for this wear from time to time.
The device for aligning the cutter bar differs in each type of
mower, yet it is to be found in all good mowers.

Secondly, the knife should be made to register, or to travel
equally over the guards at the ends of the stroke. Misadjust-
ment in this respect is often the cause of failure to cut proper-
ly. The method of adjustment varies with different mowers.
In some the length of the pitman is changed; in others, the
length of the drag bar. It is also true that many mowers
do not offer a ready means of adjustment.

Digitized by

Google

FARM MACHINERY 263

The sickle must be so adjusted under the clips that each
section will form a shear cut with the ledger plates. The
clips which hold the knife down are made of malleable iron or
steel and are adjusted by bending down with a hammer. They
must not be too tight; there should be a little clearance be-
tween the knife and the ledger plates about equal to the
thickness of ordinary paper. The guards must all be in Une
so that the above adjustment will be possible. Bent guards
may be hammered back into line, as they are made of malle-
able iron and are not easily broken. The aUgnment should
be tested by sighting over the ledger plates. If the mower
leaves streaks of long stubble, and the knife is in good con-
dition, it is quite a sure indication that one or more of the
guards have been bent out of line. The rear of the knife is
supported by steel wearing plates which assist in keeping the
points of the sections down over the guards. If these become
worn until they no longer keep the knife in place, new ones
must be put in, which may be done at small expense.

The sickle should be kept sharp at all times. It is poor
economy to use a dull knife, owing to the increase of wear
upon the machine and the poor quality of work which is sure
to be performed. All nicked or broken sections which can
not be sharpened should be replaced. If many of the sections
are damaged, it is best to buy an entirely new knife.

HAY RAKES

The Sulky Rake. The sulky rake is made either to be
dumped by hand or, by engaging a pawl on the tooth bar with
a suitable ratchet on the wheels or axle, the machine is made
self-dmnping. The self-diunp rake costs but little more
than hand-dmnp and has the additional advantages.

In selecting a sulky rake one need consider only the size
and spacing of teeth to suit the conditions to be met. The

Digitized by

Google

264 AGRICULTURAL ENGINEERING

teeth are made in two sizes, of Ke-inch and J^inch round steel,
with one or two coils at the top to give more or less elasticity
and with either pencil or chisel points. The teeth are spaced
from 33^ to 5 inches apart. The heavier rakes are used for

Fig. 165. A modern self-dump sulky rake at work.

the heavier crops like alfalfa and sorghum. A rake should
be so constructed as to be easily dimiped and to thoroughly
clean itself.

Side-delivery Rakes. The side-delivery rake has much
the same fimction as the tedder. Instead of merely tiuning
the hay, however, the side-deUvery rake has a revolving
toothed cyUnder acting in the opposite direction and set at
such an angle as to deliver the hay to one side in a loose,
fluffy windrow through which the air can circulate readily.
Where the hay is light, it is put in good shape for the hay-

Digitized by

Google

FARM MACHINERY 265

loader. Where the hay is extremely light, two windrows
may be thrown together.

There is much difference in the mechanism of the side-
delivery rakes. In general, there are two types: (1) the one-
way rake, which has revolving forks to throw the hay to one
side into a windrow; and (2) the reversible rake, which gathers
the hay and conveys it onto an endless apron across the ma-
chine and which may be driven in either direction. The iirst
type is in more general use and is the cheaper machine.

Fig. 166. A three-bar side-delivery rake at work.

The fork machine, which is much like the tedder except
that the forks are set in an oblique row and throw the hay
forward and to one side, are preferred by many practical hay
growers. Cyhnder rakes, with teeth to catch the hay and
roll it to one side, have the advantage of simplicity, but the
rolUng action given to the hay tends to make it into a close,
compact, rope-like windrow through wMch the air does not
circulate as readily as it might. Many of the fork machines

Digitized by

Google

266 AGRICULTURAL ENGINEERING

are so arranged that the direction of the throw of the forks
may be reversed and the rake used as a tedder,

HAY LOADERS

Where hay is stored in the bam, the modem hay loader
is ahnost indispensable, as its use will pay for itself in the
saving of labor in one or two seasons. In general, there are
two types of hay loaders: the fork loader and the endless-
apron or carrier loader. The first of these is of simpler con-

Fig. 167. A fork hay loader at work.

struction and is a machine that forces the hay well onto the
load.

The endless-apron loaders have one main advantage, and
that is they do not agitate the hay severely and do not tend
thereby to shake off the dry leaves. This advantage applies
only in the handling of such crops as clover, alfalfa, and
others whose leaves are easily shaken off. The endless-
apron machine does not force the hay onto the load readi-
ly, for, when the hay is allowed to pile up at the end of the
loader, the apron tends to drag the hay back. At least one
loader has been brought out recently with the apron above
the hay instead of below, in an attempt to overcome this

Digitized by

Google

FARM MACHINERY 267

difficulty. In selecting a loader, it would be well to see that
it will pick up the hay cleanly, either from the swath or the
windrow ; will pass over the obstructions, and at the same time
will not pick up old trash which may be on the surface of the
ground. The loader is made largely of wood in the fonn of
light strips, and for that reason should be carefully housed
when not in use.

HAY TEDDERS

Modern haying methods demand that the hay be cured as
quickly as possible and that it shall not lie in the sim or dew
to become bleached and stained. To do this, the drying of
the plants must be hastened by the circulation of air through
the loose hay. The leaves give up moisture to the air rapidly
and draw upon the supply in the stem, and for this reason
they should be prevented from drying up and falling ofif .

The tedder is a machine arranged to pick the hay from
the stubble where it has fallen from the mower and has been
tramped down more or
less by the team's walk-
ing over it, and throw it
into a light flufify layer
through which the air
may freely circulate.

The size of the ted-
der is designated by the
niunber of forks which
stir up the hay. The 8- and 10-fork machines are the
sizes in general use. Most of the modem machines are
made almost entirely of steel and, when carefully braced to
^ve rigidity, are often preferred over the modem wooden-
frame machines. Various combinations of gears, sprockets,
and chains are used to drive the shaft giving motion to the

Figr. 168. A steel frame hay tedder.

Digitized by

Google

268 AGRICULTURAL ENGINEERING

forks. One does not seem to have any special advantage over
the other. The chain, is the more flexible connection and
costs less to repair than a broken gear when an accident
occurs.

MACHINES FOR FIELD STACKING

In many localities where hay is one of the principal crops
it is common practice to stack the hay in the field mitil a time
when it may be disposed of either as loose hay or by baling
and shipping. The factory-made machines used for field
stacking are the sweep rake and the stacker. Each of these
machines may be secured in a variety of styles.

Sweep Rakes. The sweep rake may be a simple affair
drawn over the stubble on skids or runners, or it may be

Fig. 169. A haying scene showing an over-shot stacker and sweep
rakes at work.

mounted upon wheels with elaborate mechanism for balanc-
ing and raising the teeth. With some of these rakes the
team is divided and one horse placed at either side, and with
others the team is hitched to a tongue in the rear. The
latter type, generally called the three-wheeled rake, is the
more expensive and, although the team may be handled to
better advantage, is difficult to guide.

Digitized by

Google

FARM MACHINERY 269

Stackers. Field hay stackers are divided into two classes,
the plain overshot and the swinging stacker. The first has
a row of teeth, corresponding to the teeth of the sweep rake,
on the end of long arms hinged near the ground. The hay
is left upon these teeth by backing away the sweep rake. By
means of a rope and pulleys the teeth are raised to a vertical
position and the load of hay allowed to slide back onto the
stack. The objections of this type of stacker are that the
hay must always be raised to a certain height regardless of
the height of the stack, and the hay is always dropped in the
same place on the stack, causing it to settle unevenly.

The swinging stacker has a row of teeth on arms which
may be raised to any height and locked in place by a brake
engaging the rope; then the hay may be swung over the stack
and dumped. As there is some choice as to where the load
may be diunped, this style of stacker offers several advan-
tages. It may also be used in loading hay onto the wagons.

Homemade Stacker. Homemade field stacking ma-

Flg. 170. A homemade field stacking outfit.

Digitized by

Google

270 AGRICULTURAL ENQINEERINQ

chines are quite generally and successfully used. In addition
to homemade models of the machine described, the hayfork
can be successfully used to unload hay from a wagon onto a
stack by the use of some sort of pole and pulley arrangement,
as illustrated. Where a hay loader is available, this system
of stacking offers advantages where the hay must be hauled
some distance before stacking and where it is desired to build
an especially high stack. Apparatus for doing field work
with the hayfork may be purchased by those who do not
care to make their own outfits.

BARN HAY TOOLS

Bam Equipment. The equipment for putting hay into
bams consists essentially of forks or slings to hold the hay
while being moved from the load, hay carriers with ropes and
pulleys, and a track on which the carriers run.

Forks. There are at least four types of hayforks in use,
each of which is adapted to particular conditions. The
single tine has spiu*s at the lower end which stand out at right
angles to hold the hay. The hay is released by tripping the
spurs, allowing them to turn downward. The single-harpoon
fork is adapted to handle hay which hangs together, and is
used where it is not desired to Hf t large quantities at one time.

The dovble-harpoon fork is much similar to the single-
harpoon fork except that two tines are provided instead of
one. It may be secured in lengths from 25 to 35 inches.

The derrick fork is used quite generally for handling alfal-
fa in the field, but is adapted to a variety of conditions. It
consists of a frame with four tines at right angles. It is
very easy to insert into the hay.

,The grapple fork is used witK short hay. It is provided
with curved tines which swing toward each other like ice
tongs, ~firndygrix)ping the^ hay. The tines are of various

Digitized by

Google

FARM MACHINERY 271

lengths to suit conditions, and vary from four to eight in
number. The latter may be used in handling manure.

Fig. 171. Types of hay forks In general use: 1 is the simple harpoon,
2 the double harpoon, 3 the derrick fork, and 4 a four-tined grapple
fork.

• Slings. Hay slings are webs made up of ropes and stick
which are placed under and in the load of hay in such a way
that the projecting ends may be brought together and the
hay lying in the sUng raised at one time. To release the
hay, a spring catch is provided in the middle which allows
the sUng to part when tripped.

Hay may be handled very quickly with sUngs; as much
as 1000 pounds may be handled at one time if the equipment
is strong enough. Thus a wagon-

is strong enougn. Inus a wagon- > ^ A — ~K^

load of hay may be removed in ^ y^ :=^^^^ ~yfi

three or even two sling loads. To >l r >l k^

obviate the trouble of placing a ^'^' ^"- ^ *^^^ »"°«^-
shng within a load, a fork may be used for all but the last
which may be taken up clean by a sling on the rack.

Carriers. Carriers are made specially for forks, for sUngs,
or for both. The latter kind is known as a combination car-
rier. The size varies much with the service. light carriers
are used with forks, and heavy carriers with double trucks
are used with slings. Carriers which may be used in either
direction from the stop in the track are called "two-way

Digitized by

Google

272 AGRICULTURAL ENGINEERING

carriers/' If the lower part of the carrier can be turned

about without removing from the track, the carrier is said

to be reversible.

Tracks. A rather large variety
of steel and wooden tracks for car-

\ riers is found upon the market.

The wooden track is usually made
of material four inches square.
Steel tracks usually have a T or
cross form of cross-section. Often
the latter is called "double-
beaded" tracks. Various forms

Pig. 178. A hay carrier on a Of SWitchcS are prOvidcd tO COnVCV

Bteei track, ^^^ .^ different directions frdm

the point of loading. In round bams, pulleys are provided
for carrying the rope around the circular track.

QUESTIONS

1. What is the standard cutting mechanism for mowers?

2. Describe the two general types of mowers.

3. Discuss some of the important features of construction.

4. Why is a gear drive preferable to a chain drive?

5. What parts of a mower are subject to excessive wear?

6. Describe the two principal adjustments of a mower.

7. Explain the points to consider in selecting a sulky rake.

8. Explain the construction and use of the hay tedder.

9. Describe two types of side-delivery rakes.

10. Describe two types of hay loaders and give the merits of each.

11. State the difference between overshot and swinging stackers.

12. How may homemade outfits be arranged for field stacking?

13. Describe the usual bam equipment for handling hay.

14. Describe the construction of single- and double-harpoon,
derrick, and grapple forks.

15. What advantages do slings offer for unloading hay?

16. Describe the different hay carriers.

17. What kinds of hay carrier tracks are in general use?

Digitized by

Google

CHAPTER XL
MACHINERY FOR CUTTING ENSILAGE

Types of Cutters. There are two general types of ensilage
cutters upon the market, and a third which is used to a Umit-
ed extent. These types may be best distinguished by the
shape of the knives which are used. The first is the radial
knife machine, the cutting knives of which are attached to the
side of a large balance wheel. These knives make a shear
cut with the cutting plate over which the fodder is fed. The
second type may be designated as the twisted knife machine.
The knives of this type, which are two to four in number,
are attached to spiders on the main shaft, the knives being
twisted to such an extent that a cylinder is formed. The

Fig. 174. An ensilage cutter of the radial-knife type equipped with
blower at woric.

273

Digitized by

Google

274 AGRICULTURAL ENGINEERING

fodder is fed directly into the cylinder. The third type of
machine has a large number of narrow, hook-shaped knives
arranged spirally aromid the main shaft, and may be desig-
nated as the spiral knife machine. These cut as well as split
the fodder as it is fed directly into the cylinder.

Considering the relative merits of these various types of
machines, the radial knife certainly has the advantage in
simplicity. The fan blades are attached directly to the
main cutting wheel, and this single rotating part forms the
principal portion of the machine. All that is required in ad-
dition is the feeding mechanism. The knives of this machine
are more easily sharpened, as they are at least straight on
the flat side. As the knives are often supported their entire
length, they may be thinner, requiring less grinding in
sharpening.

irig. 176. Cutting heads of three types of ensilage cutters; 1 is the
radial knife, £ the twisted knife, and S is the spiral knife.

The twisted knife machine is capable of very rigid con-
struction and is safe against an explosion from overspeed.
The spiral kmves may be sharpened by filing without being
removed from the machine. Most machines can be

Digitized by

Google

FARM MACHINERY 275

furnished with interchangeable shredder knives for prepar-
ing dry fodder.

Elevating Mechanism. The pneiunatic elevator, or
blower, offers many advantages over the carrier elevator.
It is easily adjusted to a silo of any height and is less likely
than others to cause trouble. It requires considerably more
power; in fact, without any definite information, it would
seem that in many cases the blower requires at least one-half
of the power suppUed. If the engine is large and there is a
surplus of power, the convenience of the blower may overbal-
ance its extravagance in consuming power. The blower is
more durable than the long chain elevators. It must be
driven above a certain speed or sufficient blast will not be
developed to elevate the silage. The blower pipe should
always be set nearly vertical, or the silage will settle to one
ride of the pipe and not be elevated.

Self-feed. The advantages of the self-feed are so great
that every machine should be provided with one. This self-
feed should be capable of having its speed adjusted to fimiish
a desired length of cut. The length of cut may be varied in
some machines from J^ inch to IJ^ inches. Three-fourths
of an inch is the popular length of cut among many feeders.
In addition, the force feed should have a safety lever for
instantly reversing the feed rolls and carrier in order to pre-
vent accidents.

Mounting. Ensilage cutters may be mounted either on
skids or on trucks. The trucks add much to their conveni-
ence, and should always be provided for the larger machines.
In selecting the machine it is well to notice if the truck is of
good substantial construction. There has been a tendency
to use very small wheels, often of cast-iron, which are very
Uable to break.

Digitized by

Google

276 AGRICULTURAL ENGINEERING

Construction. Although simplicity is desirable, care
should be used in selecting a cutter to see that it is provided
with a good strong main shaft, supported in good, long,
babbitted bearings, and mounted in a substantial frame.
The gearing should be strong enough to stand the variable
load. The rolls should be flexible so as to grip the fodder
firmly. The self-feed should be mounted either so as not to
require folding when changing location, or so as to be easily
folded.

Selection of an Ensilage Cutter. The selection of an
ensilage cutter is rather a difficult task, as these machines

are of quite recent de-
velopment and accurate
information concerning
the relative merits of the
various types is not at
hand. In deciding upon
the* size or capacity of
cutter, several factors
are involved. On the
average it will be found
that a cutter will require
about one horsepower
for each ton of capacity
per hour.

The gasoline engine,

Fig. 176. A twisted-knife ensilage cutter •xt.^- rvri*.+oKl/* rv« +*.*»/»
equipped with chain-carrier elevator. eii;ner portaDie Or trac-

tion, makes a good
power for driving the ensilage cutter. Its principal ad-
vantage lies in the fact that it does not require constant
attention. As many farmers have gasoUne engines, the
cutter must often be selected to suit the engine. The power
to be used and the type of elevator are points to consider in

Digitized by

Google

FARM MACHINERY 27T

deciding the size. It is quite an advantage to have a machine
large enough to take the bound bundles of fodder without
cutting the bands. The smallest cutter equipped with a
blower which will do this will require at least a 12-horse-
power en^e, and the en^e must be Uberally rated to work
successfully.

The common practice of using the steam traction engines
of the neighborhood to furnish the power is to be commended;
first, because there is not an extra outlay of money for ma-
chinery; and, secondly, because the ordinary traction engine
furnishes abundant power for even the largest cutters.
When these large engines are used, it is best to buy a large
cutter and rush the silo filling through. The com harvester
may be operated several days before the silo filling begins,
in order that the fodder will be available as fast as needed.

QUESTIONS

1. Describe three types of knives for ensilage cutters, and state
some of the advantages for each.

2. What are the two types of elevators used for elevating ensilage?

3. What is the usual length of cut of com silage?

4. Upon what kind of truck should the ensilage cutter be mounted?

5. Describe some of the important constructional features of an
ensilage cutter.

6. What are some of the important factors to be considered in mak-
ing a selection of an ensilage cutter?

Digitized by

Google

CHAPTER XLI
THRESHING MACHINES

Development. It is a big step of progress from the simple
flail to the modem threshing machine. The use of the flail
required the time of a man for the entire winter season to
thresh even a very moderate crop of small grain which he had
grown; whereas the modem machine is able to thresh hun-
dreds or even thousands of bushels in a single day, delivering
it cleaned and ready for market.

The Operation of Threshing. The modem threshing ma-
chine performs four quite distinct operations. The first is the
process of threshing or shelling. This is accomphshed when
the unthreshed grain passes between the teeth of a revolving
cylinder and those arranged in the concave. Second, the
machine separates the straw from the grain and chaff. This
operation is performed by the grate, the beater, the check
board, and the straw rack. Third, the grain is separated
from the chaff and dirt by screens in the shoe and by a blast
from the fan. Fourth, by means of the stacker and the grain
elevator or weigher, the straw is dehvered to one point and
the grain to another.

Cylinder. The cylinder of a threshing machine is built
up with heavy bars of steel mounted on disks or spiders, into
which the teeth are fastened by thread ends and nuts or by
keys. There are two sizes of cylinders in use, known as the
small and the big cyUnder. The big cyUnder usually has
about 20 bars. The speed at which a cyUnder revolves will
depend upon its size, but varies from about 800 revolutions
for the big cyhnder to 1100 revolutions for the smaller one.

278

Diaitized bv

Google

FARM MACHINERY 279

The Concave. The concave is made up of heavy bars
into which teeth similar to cylinder teeth are fastened. It is
located below the cyhnder, and receives its name from its
shape. The nmnber of rows of teeth may vary according
to the kind and condition of threshing, and may be varied
by inserting removing bars. The concave may be adjusted
by raising or lowering, the threshing efifect being greater
when the teeth are high and entered well into the teeth of
the cylinder.

The Grate. The grate consists of a number of parallel
bars with open spaces between, placed directly beyond the

Fig. 177. A section of a modern threshing machine.

concave teeth. A large part of the grain and chaflf is allowed
to pass through this grate before reaching the straw rack
beyond.

The beater is a webbed wheel beyond the cylinder, which
beats the straw into a stream as it comes from the cylinder
and enables it to be passed quickly over the straw rack.

The Straw Rack. The straw rack is a vibrating rack
which allows the stream of straw to pass over it but which
sifts out the grain. There are many types of straw racks
in use, and these vary in their construction and shaking
motion.

Digitized by

Google

280 AGRICULTURAL ENGINEERING

The Grain Pan or Conveyor. This is a sohd removable
bottom which extends from the cylinder back to the shoe
and catches all of the grain coming from the grate and
through the straw rack.

The Shoe. The shoe is the frame which carries the
sieves. In it the grain is separated from the chaff as the
grtdn and chaff pass over the sieves and strike a blast of air
from the fan. The sieves and the blast from the fan are sub-
ject to adjustment, and upon their skillful manipulation
depends largely the efficiency of the machine in cleaning the
grain.

The Self-Feeder and Band Cutter. The self-feeder is an
attachment which receives bound bundles and elevates them
to the throat of the cylinder, cuts the bands, and uniformly
and evenly feeds the grain into the cylinder.

Straw Stackers. Formerly the straw was taken care of
by a carrier, which consisted of a frame over which an end-
less web was drawn. Later this type of carrier was made
to swing in different directions from the machine. Most
machines of the present day are equipped with wind stack-
ers, or blowers. These stackers have a fan which receives
the straw from the straw rack and blows it to any part of
the stack desired, reducing the amount of labor involved.

The Weigher. The majority of modem machines are
equipped with a weigher to measure the grain as it is deUvered
into the wagon or into bags. If the machine is simply pro-
vided with an attachment to elevate the grain into the wagon
box, the attachment for so doing is called the grain elevator.

Size of Threshing Machines. There are usually two
dimensions given to a threshing machine, or separator: the
first is the length of the cylinder, and the second is the inside
width of the machine, where the various separations of grain,
straw, and chaff are brought about. The sizes vary from

Digitized by

Google

FARM MACHINERY 281

18x22 inches to 44x66 inches, and 32x54 inches to 36x58
inches. The 36x58-inch separator requires from 25 to 40
actual horsepower to operate it successfully; and such a
machine will thresh from 500 to 1000 bushels of wheat in
a day, or about twice as much oats.

Selection of a Threshing Machine. The choice of a
threshing machine will depend largely upon the amount of
grfdn to be threshed and also upon the method followed in
threshing. In the United States, it is customary for the
threshing to be done by experts who make a business of that
kind of work. There are some locaUties where the individual
farmer owns a threshing outfit, in which case the smaller
sizes are used. Special machines are provided for special
conditions. The threshing of beans and peas requires a
special machine, as well as the threshing of clover.

QUESTIONS

1. Describe the four distinct operations performed by the modem
threshing machine.

2. Name the parts that perform each operation.

3. Describe the construction of the cylinder.

4. Describe the concave and its adjustment.

5. What is the main purpose of the grate?

6. Where is the straw rack, and what work does it perform?

7. What is the purpose of the grain pan?

8. What function is performed by the shoe?

9. Describe the construction and work of the self-feeder.

10. What is the work of the weigher?

11. How is the size of threshing machines designated?

12. What are some of the important considerations involved in the
selection of a threshing machine?

Digitized by

Google

CHAPTER XLII
FANNING MILLS AND GRAIN GRADERS

The Use of a Fanning Mill. The final selection of small
grain seed must be made by mechanical methods. The
plant breeder may well afford to make a hand selection of
seeds, but the practical grower will find it quite impossible.
There are from 700,000 to 1,000,000 wheat berries, about
12,500,000 alfalfa seeds, and as many as 120,000,000 tunothy
seeds in a iDushel. A bushel of corn contains about 100,000
kernels; but only 3^ to ^ bushel is required to plant one acre,
which permits seed com to be graded by hand more readily
than other grains. However, it is more likely not to be done
at all.

Another vital requirement of good seed is that it shall not
be mixed with any weed seeds which will foul the land and
reduce the value of the crops. Also, in order that the modem
seeding and planting machinery may do its work best, the
seed should be free from trash and be imiform in size and
weight. The first step to be taken in securing a uniform
stand lies in cleaning and grading the seed.

Often two or more grains are grown together or become
accidently mixed, and the fanning mill is called upon to sepa-
rate out the different kinds. To summarize, the functions
of the fanning mill are:

1. To clean grain, separating out trash and foul seeds.

2. To grade grain, securing the best seed.

3. To separate different kinds of grains.

What the Fanning Mill Can Do. The fanning mill or
grain grader can grade clean, or separate grains only when

2S2

Diaitized bv

Google

FARM MACHINERY v 283

there are certain physical differences between the grains to
be separated. It is reasonable to think that no machine can
separate two grains whose difference Ues wholly in the name
or color. The modem fanning mill is arranged to utilize
several of the physical differences which may exist between
grains. These differences may be, (1) difference in weight,
(2) difference in size, (3) difference in shape.

In addition, the roughness of the hull and the location of
the heavy part of the seed may be used to some extent in
making certain selec-
tions or separations. A
separation based upon
a variance in weight is
made by the use of a
strong current of air.
Some grain graders use
this method almost
entirely at the present
time, and formerly all
machines depended
principally upon "fan-

*^, -- J PIff. 178. A section of a fanning: mill in

mng to do the Sepa- which the blast does not strike the grain

, ., until after it has passed through the sieves.

rating, hence the name

fanning mill. No doubt, the heavier grains are the most
desirable for seed, and therefore fanning is the most im-
portant featm-e of the modem fanning mill.

Sievesi screens or riddles are used to grade the grain
according to size. The grain first passes through a coarse
screen, which takes out all the large particles, then over a
finer sieve, or a combination of finer sieves, which lets the
small grains and weed seeds through and which retains the
larger seeds in one or more grades.

Digitized by

Google

284 AGRICULTURAL ENGINEERINQ

Striking examples of how use is made of differences in
shape are found in the devices arranged to separate wheat
from oats. In one device a riddle is provided with cells
having a reverse turn. The short wheat grains are able to
pass through this riddle, but the long oat kernels cannot.
Another device consists of a cloth apron over the grain on
the sieve, which maintains the grain in a thin layer and pre-
vents the long oat kernels
from passing through,
because the cloth pre-
vents them from being
upended. The wheat
kernels, being shorter,
pass through without
diflSculty.
1 Certain grains like
rye, for example, are
heavier at one end of
Fi«r. 179. Another view of the type of the bcrry than at the

machine shown in Fl«r. 178. ^^j^^^^ ^j jj ^j^^ ^^^j^

are allowed to fall a certain distance they are quite likely to
strike upon their heavy ends. This principle is made use
of to a certain extent in some machines.

Some of the weed seeds which are found in grass seed
have a homy or burr-Uke hull which enables the seeds to
adhere readily to any cloth with which they may come in
contact. This characteristic of the seeds is made use of, in
separating them out, by passing the seed in a thin stream
over a felt roll.

In general, there are two types of fanning machines:
First, those in which the air blast is directed upon the grain
as it passes over the sieves; and second, those which use the
air blast independent of the sieves and riddles. The first of

Digitized by

Google

FARM MACHINERY 285

these is the older type. It has a rather large capacity for
the amount of sieve surface provided, and when properly
handled will do good work. The latter type, however, has
the greater refinement and is capable of more careful selec-
tions.

The Selection of the Fanning Mill. There is a tendency
among certain manufacturers to build a fanning mill of such
Ught construction as to be neither dm-able nor able to with-
stand hard service. These mills soon become rickety and loose
in all of the joints. Therefore, in making a selection of.a fan-
ning mill, after deter-
mining definitely that it
will do the desired work,
it should be carefully
examined to see whether
or not the frame and
the body of the machine
are made of good mate-
rial and well put to-

Flg. 180. A section of a fanning mill In gcthcr. WoodcU kcyS
which the blast Is directed below and ^^j «,«:i« «„ -^^«^« ^f
through the sieves. S^Cl naiiS aS mcaUS 01

fastening the joints
should be guarded against. The shoe which carries the sieves
should be well made to withstand the constant vibra-
tion to which it is subjected, and conveniently arranged
for the adjustment of the sieves. It is best that the length
of the shaking stroke be subject to adjustment, as small
seeds require a shorter stroke than large ones.

Operation and Care. The air blast should be subject to
regulation, either by changing the speed of the fan or by
varying the volume of air supplied, which will permit it to
be adapted to all conditions. Too little attention is often
given to the construction of the sieves. The frames should

Digitized by

Google

286 AGRICULTURAL ENGINEERING

be made of selected material and well put together, and the
wire cloth should be firm and not easily distorted. Perfo-
rated sieves are the best when made of zinc. They are
the most acciu'ate, as the perforations are quite sure to be of
the same size. Their capacity, however, is less, and they
prevent the passage of a blast of air through them.

Sieves should be well cared for. A punctiu-edor sagged
sieve has its eflSciency very much reduced. It would be well
to provide a rack for storing the sieves while not in use.
The practice of piling them one upon the other is not at all
to be commended.

QUESTIONS

1. Why is the fanning mill necessary in the grading of small-grain
seed?

2. What are the three functions of a fanning mill?

3. Upon what three physical differences in seed does separation
depend?

4. What devices are used to separate by differences in weight? In
size? In shape?

6. Describe two types of fanning mills.

6. What points of construction should be observed in making a
selection of a fanning mill?

7. Describe the adjustments of the blast and sieves in a fanning
mill.

8. Of what materials are the sieves made, and what is the ad-
vantage of each?

9. How should the sieves be cared for?

Digitized by

Google

CHAPTER XLIII
PORTABLE FARM ELEVATORS

The Portable Elevator. One of the most recent machines
which has been developed to reheve the farmer of some of the
hardest work to be found upon the farm is the portable ele-
vator. Nothing is more tiring than shoveling com into a
crib after husking all day. The shoveling of wheat and
other small grains into the granary at threshing time is like-
wise laborious. The portable elevator not only does away
with the hard work but also saves time and reduces the help
required, both of which are to be obtained only at a premium
during a rush season. A good elevator will do the work of
from two to five men.

Besides saving labor, time, and men, the portable elevator
makes possible the construction of more economical cribs and
granaries. These can be built much higher, thus increasing
their capacity without increasing the cost of the roof or the
foimdation. With elevators, one is not compelled to build
cribs or granaries on low foundations when wet ground
makes it undesirable.

In general, the portable elevator outfit consists of a dump-
ing jack to lift the front wheels of the wagon and cause the
load to flow to the rear ; a hopper into which the load is fed ; an
inclined elevator with a chain carrier of flights or cups, which
carries the grain to the highest point in the crib; a spout or
conveyor to distribute the grain in the crib; and some som-ce
of power, either horse power or engine.

The Lifting Jack. The Ufting jack is made in two styles,
the overhead and the low-down. The former has a yoke or

287

Digitized by

Google

288 AGRICULTURAL ENGINEERING

frame under which the load is driven; the lifting is done with
either ropes or chains running over pulleys above and back
to a windlass below. The overhead type is the simpler of
the two, but is a little inconvenient to move. Bopes are
cheaper than chains/ but are less durable.

Nearly all of the various devices known for heavy lifting
are used with fairly good success, such as the worm gear, the
screw and nut, the hydraulic lift, the rack and pinion, and the
windlass. The worm gear with windlass is one of the most

Flfir. 181. A portable farm elevator mounted on a truck and equipped
with a folding hopper and a low-down dumping Jack.

comjnon and most satisfactory. As a usual thing, a rough-
cast worm gear is not a lasting part of a machine, and if port-
able elevators are to be put in constant use no doubt greater
refinement would be necessary at this point.

The pump and cylinder, or the hydraulic jackSf are built
with lifting chains extending down to the hubs of the front
wheels, or with the cylinder placed directly under the front
axle. In the latter type the piston rod has a yoke at the top
which engages the axles and raises the entire front end of the

Digitized by

Google

FARM MACHINERY 289

wagon as the oil, which is always the fluid used, is pumped
into the cylinder below the piston. The hydraulic jack does
not raise the load with an even motion, owing to the intermit-
tent action of the pimip.

The screw and, nvi device acting upon the principle of the
screw jack has one bad feature, and that is the lack of pro-
tection of the screw from rust and dirt, as it must be bright
and well lubricated at all times. The rack and opinion is a
device used on at least two makes. This is connected to the
front end of a platform at each comer, and the wagon is
raised on the platform. This method obviates the difficulty
of dumping wagons of long and short wheel bases. All jacks
should have a quick return motion for returning the wagon
to place.

Wood and steel are used in the construction of the dump-
ing jack. Owing to the fact that this implement is usually
exposed more or less to the weather, during its season of use,
at least, the steel construction is to be preferred. If the jack
is to be moved from place to place often as conditions may
require, it should be provided with a truck, which most manu-
factm-ers will furnish at a slight extra cost.

The Hopper and Elevator. The hopper, or elevator
extension, is made so as to be raised to a vertical position or
swung to one side so that the load may be driven into the jack
or diunp. In the first type, to assist in lifting the hopper,
springs or a windlass should be, and usually are, provided.
The carrier may be continuous through the hopper and the
elevator, or a separate carrier or web may be provided for
each. The first arrangement permits the hopper to be placed
nearer the ground, but has a tendency to overload the chains
of the carrier, which, in many cases, have too much to do for
their strength. The low hopper is a decided advantage in
unloading a low-wheeled wagon.

10—

Digitized by

Google

290 AGRICULTURAL ENGINEERING

Cups and Drag Flights are used for conveying the griun
up the carrier. The cups seem to be of the most desirable
oonstruction when the loaded weight is carried upon rollers.

FifiT. IS 2. A portable elevator equipped with an overhead dumpinff
Jack, swlnsr hopper, and conveyor for distributing the grain.

In the first place, these carriers will be the more dm-able, as
the scraping action of the flights cannot help but produce
an undue amount of wear, even when guides are provided
to keep the flights free from the bottom of the elevator
trough. In the second place, the cups will handle any kind
of grain.

The Derrick and the Conveyor. The derrick for holding
the elevator at the proper angle is an important part of the
machine. It should be so arranged that it may be erected
quickly after being folded down, and should be provided with
a powerful windlass. Cables are more durable than ropes,
especially when greased occasionally to prevent rust.

If the elevator is to be moved often, the elevator proper,
the hopper and the derrick, should be mounted on a truck.
Some of these trucks are very cheaply constructed; yet, unless
the elevator is to be moved far and often, an expensive truck
is not needed.

Digitized by

Google

FARM MACHINERY 291

All elevators can now be secured with conveyors which
may be installed in the ridge of the crib or granary and which
permit the grain to be discharged through a spout to any
point. This is accomplished usually by having spouts to fit
into removable sections of the bottom, or by shifting the
whole conveyor on rollers. K the elevator is to have a perma-
nent position in the building, the conveyor is almost essential.
If the building is not too large, a better arrangement is to ele-
vate the grain to the highest point possible, often to a cupola,
and distribute it through a spout to the bins. The conveyor
complicates the machine, and should be dispensed with if
possible.

K a two or three-horsepower gasoline engine is at hand,
it may conveniently be used to furnish power for the farm
elevator; otherwise, a one or two-horse sweep-power should
be purchased.

Selection. The selection of a portable elevator finally
resolves itself into the choosing of a machine to suit the kind
or kinds of grain to be elevated, and a careful inspection of
the construction of the machines, as well as obtaining from
the maker a guarantee insuring a satisfactory performance.

QUESTIONS

1. Why is the portable elevator an important machine for the farm?

2. Describe the various mechanisms which are made use of in the
lifting jack. i

3. Describe some important features of the construction of a
portable elevator.

4. Of what materials are portable elevators made?

5. What are the relative merits of cups and flights?

6. Describe the construction of the derrick. j

7. How are conveyors used in large cribs?

8. What features should be given careful consideration in the
selection of a portable elevator?

Digitized by

Google

CHAPTER XLIV
MANURE SPREADERS

The Utility of the Mantire Spreader. The manure
spreader will not only enable an operator to spread much
more manure in a given time than it would be possible to do
by hand with a fork, but better work is performed. A ma-
nm-e spreader will thoroughly pulverize the manure and
spread it in an even layer over the field. When hand
spreading is practiced, the manure is not properly pulverized
but is spread in large chunks or bunches, which "fire fang,"
thus causing a large part of the fertihty to be lost.

Construction. A manure spreader consists essentially
of four parts: (1) A box with a flexible, movable bottom,
called an apron; (2) gearing, or a mechanism to drive, at vari-
ous speeds, the apron conveying the manure toward the
beater; (3) a beater or toothed drmn, which receives the
manm-e from the apron, pulverizes it and spreads it evenly
behind the machine; and (4) a truck to carry the box and to
enable the power to drive the machine.

FifiT. 183. A modem manure spreader at work.
292

Diaitized bv

Google

FJLRM MACHINERY 298

Types. There are two general types of manure spreaders,
dass^ed by the constoiction of the aprons. The endless
apron passes over rollers or reels at each end of the box, and
is arranged to be driven in one direction only. As soon as
a load is discharged, the apron is stopped and is ready to
receive another load. This type of apron is more likely
to become fouled by manure passing through the upper side
and lodging in the inside of the apron below. In freezing
weather this manure on the inside becomes frozen, and is
quite Ukely to cause breakage. The slats are placed quite
close, however, and in many instances these troubles are
not experienced at all. One maker of the endless apron
spreader has the slats of the apron hinged so that while on
the under side they hang vertically, preventing the manure
which comes through the upper side from lodging below.
Again, another style of endless apron does not have slats
over much more than half of its length, and in this way
prevents fouling by leaving the under side open. In other
instances the apron proper is replaced with a drag chain
which drags the manure over the tight floor of the box.
Usually this type of apron, or conveyor, to be more correct,
is used only with the small-sized machines, as the amount
of power required to drag the load is much greater than to
move it on an apron supported by rollers.

The return apron, after discharging its load, is brought
back into position again by a reverse motion. The return-
apron spreader has more mechanism than the endless apron,
on account of this return motion. The front end board is
attached to the apron and draws the load well into the beater
at the finish.

A few endless-apron spreaders have a front end board
that moves with the load, and which, after the load has been
spread, is brought forward again by hand.

Digitized by

Google

294 AGRICULTURAL ENGINEERING

Main Drive. The main drive from the rear wheels, which
furnish the power to the beater, is an important part of the
spreader. Gears and chains are used to transmit the power.

Chains offer an advan-
tage in case of breakage,
as a chain can be easily
and cheaply repaired.
Breakage is more likely
to occur when starting
the machine than at any
other time. To prevent
the beater from throwing

Fig. 184. One type of driving mechanism OVCr a big bimch of ma-
te the beater. nurc whcn put in motion,
a rear end board is provided, which is raised when the ma-
chine is started. The beater may also be moved away from the
manure when going into gear, thus overcoming this difficulty.

The Beater. The beater for pulverizing the manure is
made up of bars of teeth which revolve at a relatively high
speed against the manure fed to it by the apron. It
should be constructed of durable material; wood bars are
generally used to hold the teeth, but beaters made entirely
of steel are used on a few machines. The size does not seem
to be so important so long as the teeth are given the proper
speed to pulverize the manure well. The height of the beater
in reference to the apron is important, for if placed too low it
tends to drag the manure over without pulverizing it. Beaters
placed high are quite likely to cause the machine to be of
heavy draft.

The teeth of some beaters are placed in diagonal rows
around the beater, which tends to comb the manure from the
center, where the load is the deepest, toward the outside,
giving a more even distribution.

Digitized by

Google

FARM MACHINERY 295

Several devices have been invented to spread the manure
over a wider swath than the width of the machine. Under
average conditions the machine requires all the power avail-
able to properly pulverize the manure needed to cover the
width of the machine.

Retarding Rake. To prevent the manure from being
thrown over in large bunches, a retarding rake is provided in
front of the beater. In some machines this is given a vibra-
ting motion which tends to level the load.

Apron Drives. There are at least two mechanisms in use
for moving the apron at various rates of speed toward the
beater. One is the worm drive, in connection with a face
wheel and pinion to give variable speeds. This device gives
a uniform motion and is positive,
preventing the apron from mov-
ing too fast, as when the spreader
is ascending a hill and the load
has a tendency to slide back into
the beater. As a general rule, a
worm gear when used in this
way does not wear well. Some „. ,oe r^ * * ^ . i

of the latest machines have this mechanism to the apron.

gear inclosed so as to nm in oil.

The ratdiet drive is simple but does not give a steady
motion. It is very easy to obtain a wide range of speed with
this device. The ratchet acts only in one direction, and in
hilly localities the apron must be provided with a brake to
prevent it from feeding too fast in ascending a hill.

The return motion for return-apron spreaders is usually
separate from the feed, and safety devices are provided to
prevent the possibility of having both motions in gear at the
same time.

Digitized by

Google

296 AGRICULTURAL ENGINEERING

The Truck. The truck of the manure spreader is impor-
tant, as it is often the first part to wear out. Steel wheels
are quite generally used now, and in dry climates they are
preferable to wooden ones. It is also important that the
frame of the truck be constructed of diu-able material, which
should be well braced and trussed. Maple is to be preferred
to pine for the frame.

Capacity. The capacity, or size, of a manure spreader is
designated in bushels, but this seems to be an arbitrary unit
at the present time. As now rated the capacity would be
more nearly represented by cubic feet.

Low-down Spreaders. The latest development in ma-
nure spreaders is the low-down spreader, which is built so that

the top of the bed is very
low. It is obvious that
this type of construction
reduces the labor in load-
ing by the fork, and it
is also more convenient
for filling from a litter
oampr

Fig. 186. A low-down spreader. _., ' - « «

Wagon box Spreader.

The wagon box spreader is a machine designed to be placed
on the rear of an ordinary farm wagon or farm truck.
The power is transmitted by sprockets clamped to the rear
wheels. This machine is small, light, and cheap; it furnishes
an opportimity to use the truck for other purposes. The
manure spreader, however, is a machine in such constant
use as to demand a truck of its own.

QUESTIONS

1. Why is machine spreading of manure to be preferred to hand
spreading?

Diqitized bv

Google

FARM MACHINERY 297

2. What are the four essential parts of a manure spreader?

3. Describe the two types of aprons in use, and what are the
advantages (^ each?

4. What is a drag chain conveyor?

5. What is the use of a front end board?

6. Describe two types of main drive.

7. How should the beater be constructed?

8. What is the purpose of the rear end board?

9. State the purpose of the retarding rake.

10. Describe two systems of apron drives and give the merits of
each.

11. What points should be observed in selecting a truck?

12. How is the size or capacity of a manure spreader designated?

13. What is the advantage of a low-down spreader?

14. Describe the wagon box spreader.

Digitized byVjOOQlC

CHAPTER XLV
FEED MILLS AND CORN SHELLERS

Feed Mills. The work of the feed mill is the reduction
of grain to meal. In some machines it is necessary that this
process be acoompUshed by two stages, especially if ear com
is to be groxmd. The com first passes between a set of crush-
ing rollers and then through the main grinding mechanism of
grinding plates or buhrstones. Feed mills differ most in the
construction of the grinding plates or buhrstones.

Grinding Plates. Buhrstones are used where a very fine
meal, such as is required for table piuposes, is desired. Most
feed mills used for grinding feed for live stock have chilled-
iron grinding plates. These are hard, they wear well, and
can be easily replaced at a small expense when worn out.
These grinding plates are made in a variety of shapes, al-
though the flat or disk shape is the more common. They

are sometimes made cone shaped.
Roller mills are used to some
extent for grinding feed for live
stock. These rollers are generally
made smooth and depend upon
the crushing of the grain to reduce
it. The roller may have a nulled
surface and revolve against the fixed
part or grinding plate.

The Power Mill. Power mills
are usually arranged to be driven
by a belt or a tumbling rod. A

Fig. 187. A^belt-driven feed j^^j^^^ ^j^^^j j^ considered a dc-

298

Digitized by

Google

FARM MACHINERY 299

sirable feature of a power mill, as it enables the machine
to run more steadily. When two kinds of grain are to
be groxmd together, a divided hopper is quite an advan-
tage. Most feed mills are provided
with safety devices which release the
grinding plates and prevent damage
should something hard be fed into the
mill, or with quick releases which will piftfs of^'chined^cast
enable the operator to separate the *^^°*
grinding plates quickly. Such mills should be provided
with an elevator or sacking attachment to assist in ciaring
for the groxmd feed as it is prepared.

Selection of a Mill. The selection consists primarily in
securing a machine constructed with bearings which will nm
well and can be adjusted easily, and with grinding plates
which can be easily replaced and adjusted. The capacity
of feed mills and the amoimt of feed which the mill will grind
in a given time depend upon the condition of the grain and
the fineness of grinding. Furthermore, the capacity of the
feed mill usually becomes less and less from the time the
grinding plates are new until they are replaced. A good feed
mill should grind five bushels of com or two to three bushels

of oats for each horse-
power used.

CORN SHELLERS
There are two general
types of com shellers on
the market, one is known
as the spring or picker
sheller and the other as
the cylinder sheller.
piff. 189. A small two-hoe picker- The Sprinfif Of Picket

wheel sheller equipped with self-feeder, wi^xiAxg vx .itavac;!

oob carrier, and elevator. Sheller. The Spring Or

Digitized by

Google

300 AGRICULTURAL ENGINEERING

picker sheller is the one in more general use and is adapted
to smaller machines. The shelling mechanism consists of the
picker wheels, the bevel nmner, and the rag iron momited on
a spring. These three form a triangular open chute through
which the ears of com are fed. The rag iron is adjustable to
adapt the machine to large or small ears. On large machines
a self-feeder is provided, which arranges the ears endwise
and feeds them into the sheller. In shelUng large cribs of
com, extension feeders are provided to convey the com from
the crib to the self-feeder.

Cylinder Shellers. The cylinder sheller consists of a
beater wheel within a cyUnder made up of parallel steel bars.

Fig:. 190. A section of a picker-wheel sheller.

The com is fed into one end of the cyUnder, and, as the ears
pass along, the com is shelled by being crushed against the
cylinder by the revolving beater wheel. Cylinder shellers
break up the cobs more than picker shellers.

Separating Device. All power shellers should be pro-
vided with a shoe and sieve, and a fan to blow out the chaff
and dust. Sometimes a vibrating rack or raddle is substi-
tuted for the sieve. After being cleaned, the com is elevated

Digitized by

Google

FARM MACHINERY 801

into the wagon box, and the oobs are conveyed in another
direction by a cob carrier.

Ci^Mtcity. The size of a picker sheller is designated by
the number of "holes/' or sets of shelling wheels, and these
vary from the one-hole hand machine to power machines
with as many as eight holes. The average size is the four-
hole sheller, which will usually shell from 100 to 200 bushels
an hoiu*; the six-hole will shell from 200 to 300 bushels an

Fig. 191. A section of a cylinder sheller.

hour; and the eight-hole, 500 to 600 bushels. The cylinder
sheller is made in the large sizes only, some having a capacity
of as much as 800 bushels per hour. The power required for
operating com shellers varies with the size. The foiu'-hole
power shellers with all attachments will usually require about
eight horsepower. The power required to operate cyUnder
shellers will vary with the size, style, and the manufacturer's
number.

QUESTIONS

1. What is the work of the feed mill?

2. Describe the various types of grinding plates used in feed mills.

Digitized by

Google

302 AGRICULTURAL ENGINEERING

3. How 18 the grain reduced by means oi rollers?

4. What are some of the attachments of a feed grinder?

5. What safety device is usually provided?

6. What are some of the important features to be considered in
the selection of a feed mill?

7. How much feed may be ground per horsepower per hour?

8. What are the two distinct types of com shellers in use?

9. Describe the shelling mechanism of the spring or picker sheller.

10. Describe the cylinder sheller.

11. Describe some of the attachments provided for a sheller.

12. What 18 the ci^Mtcity of various sizes of com shellers?

13. How much power is required?

Digitized by

Google

CHAPTER XLVI
SPRATIN6 MACHINER7

Successful fruit growing at the present time depends
largely upon an intelligent and skillful fight against fungous
diseases and injurious insects. Even the small orchardist
finds that he cannot afford to overlook the spraying of his
trees at the proper time. Field sprajdng has been introduced
recently to exterminate also certain noxious weeds, such
as mustard in grain fields.

Hand Sprayers. There is a multitude of hand sprayers
or sjoinges upon the market, but it is not the piupose to take
up these. The use of these appUances is limited to the
greenhouse or to shrubbery. The bucket sprayer is one step
in advance, and may be used quite successfully on a few trees
if they are not too large. Most of these sprayers throw the
spraying solution up above the trees in such a way that the
spray falls upon the foUage. In many cases this is undesir-
able. The spray should be driven into the foUage in such
a way that the xmderside of the leaves and the inside of the
flowers will be reached by the spray solution. A Hberal use
of brass in the construction of the small sprayers is one of the
features which indicates quaUty.

The Barrel Spray Pump. The smallest and cheapest
machine for spraying small orchards is the barrel pump.
Where a few trees are to be sprayed, this is xmdoubtedly the
machine that should be selected.

The pmnp may be moxmted on either the end or the side
of the barrel. If located on the side, the pmnp will more
nearly remove all of the solution from the barrel, as the

303

Digitized by

Google

304 AGRICULTURAL ENGINEERING

suction pipe extends to the lowest point. It is an advan-
tage to have the pump low, as the handle is then in a more
convenient position. If the holes cut for the pump and the
filling funnels are not too large, a barrel in a horizontal posi-
tion, with two heads, is more rigid and less likely to go to
pieces when empty for a time.

All the working parts that come in contact with the
spray solution should be brass, as it is the only metal in use

which will resist the corrosive
action of some of the solutions
in conmion use. The valves
should be either ball or poppet,
with removable seats. The ball
valve seat may be replaced for
a nominal sum, making this
part of the pump as good as
new. Brass poppet or disk
valves may be renewed in the
same manner, or they may be
repaired by grinding. Fine
Fig. 192. A good type of barrel emery with oil is placed be-

spray pump with dash agitator. "^ -^

Note the plunger cylinder and the tWCCU the ValvC and itS SCat

large air chamber.

and the valve turned back and
forth in a rotative manner until the surfaces are groxmd
to a perfect fit.

The plunger type of cylinder has many advantages. It is
of easy access for repairs, and it is easy to determine whether
or not the plxmger is leaking. The packing is often placed
between two disks, which cause the packing to expand as
they are screwed together on the plxmger rod. The pmnp
with the stuflSng box and the inside plxmger is to be guarded
against. Of coxu^e, double-acting pxunps mxist have stxiff-

Digitized by

Google

FARM MACHINERY 305

ing boxes^ but it is doubtful if the double-acting pump
offers much advantage. If the pump cylinder is not sub-
merged, it should be placed near the surface of the liquid
in the barrel. The air chamber should be large, as it
equalizes the pressure and makes the pump easier to
operate.

Every barrel pump should be provided with an agitator
to keep the heavy spray mixtures stirred. The double-paddle
type is undoubtedly the most efficient type now in use, but
the dash agitator is in more common use and is quite efficient.

Field Sprayers. Reld sprayers differ largely in their con-
struction, as they are designed for spraying different crops,
first, in selecting such a machine, consideration should be
^ven to the truck and the tank. These should be of sub-
stantial and durable construction. The gearing driving the
pump should be of substantial construction; gears, chains
and sprocket, cranks, cams, and eccentrics are used in this
connection, but it has not been demonstrated that any one
particular combination has any special advantages over any
other. The size of the pump must vary with the niunber
and kind of nozzles to be supplied. Some of the field ma-
chines used for spraying mustard and other weeds are of
large capacity, supplying as many as twelve nozzles and
covering a width of twenty feet.

Convenience is one feature of great importance in the
field sprayer. The machine should be easy to fill and to
control. The position of the nozzles should be susceptible
of any adjustment which may be necessary. The pump and
driving mechanism should be of ready access for adjustment
or repairs.

The Power Sprayer. Where there is a considerable
amount of orchard spraying to be done, the power sprayer
will be found the most economical and efficient. Man power

Digitized by

Google

306 AGRICULTURAL ENGINEERING

is expensive, and it is well-nigh impossible to maintain suf-
ficient high pressure by hand to do the best kind of spra3dng.
Power. Steam engines have been used to some extent
as a source of power for spray piunps, or steam has been used
directly in direct-acting steam pumps. The great weight
of the steam boiler has caused its replacement by the gasoUne
engine almost entirely. The gasoline engine is cheap in first

Figr. 198. A power sprayer.

cost, cheap in operation, and is light, which make it especi-
ally adapted to the purpose.

The first requisite of a gasoUne engine for a spraying out-
fit is reliability. It must operate imder adverse conditions,
and there should be sufficient capacity to operate continu-
ously without overheating.

Pumps. The plxmger pump with outside packing of the
duplex or triplex type is now being generally used in the

Digitized by

Google

FARM MACHINERY 307

better grades of spraying outfits. Since these are more
accessible than the usual double-acting pump, they are morr
easily packed. The triplex pump furnishes a more even
flow of Uquid, but introduces extra parts and is imdoubtedly
of more expensive construction. The air chamber should
be designed to suit the kind of pump used.

The Drive. The drive from the engine to the pump is
either a gear or a combination of gear and belt. If a gear
is used, it is highly essential that the pmnp and the engine
be moimted upon the same base, thus insuring more rigid
construction.

Agitator. The most efficient tj^e of agitator for power
sprayers is the propeller type. The small screw propellers
in the tank cause the Uquid to circulate rapidly over and
over in the tank, carrying the heavy particles in the spray
mixture to the surface. Dash or paddle agitators do not
produce this action. '

The reUef valve is one of the most sensitive parts of the
modem sprayer. Its purpose is to r^ulate the pressure,
allowing the siuplus Uquid pumped to return to the tank.
The regulator valve, used in place of the reUef valve and
^which cuts off the flow to the .pmnp after a certain pressure
has been reached, is a conmiendable device, as it reUeves the
engine of part of its load and thus reduces the wear upon it.

Tank and Truck. The tank and truck should be given
careful consideration. In general, the machine which may
be moved about the most easily is the most desirable. For
this reason, Ughtness is one of the requisites of a good spraying
rig. As the sprayer must be hauled over soft groimd, high
wheels with wide tires foi the truck are desirable. The con-
struction should permit turning in very Umited space.

Accessories. The hose, extension rods, nozzles, cut-offs,
and other accessories are the things with which the operator

Digitized by

Google

308 AGRICULTURAL ENGINEERING

must work directly, and often efficient work will depend upon
their quality. Cheap hose is poor economy. The extensions
are best when made of bamboo with a brass tube on the
inside to carry the hquid. Good substantial ferrules should
be provided at the ends to relieve the thin brass tube of all
strains due to dragging a length of the hose about. A con-
venient and perfectly
tight shut-off adds
much to the pleasiu*e
of operation.

There are two gen-
eral types of nozzles in

Tig. 194. The Bordeaux nozzle and a USC: the BordcaUX
cluster of four Vermorel nozzles. ' i • i. • i.

nozzles, in which a
spray is produced by directing the jet against the edge of
the orifice; and the Vermorel, which has an eddy chamber
directly below the orifice. In the latter, the liquid is given
a whirling motion, causing it to be driven from the orifice
in a cone-shaped spray.

The Bordeaux nozzle produces a fan-shaped spray, which
has considerably more force than the spray from the Vermorel
nozzle. The latter is generally known as the fine-spray^
nozzle; by making the eddy chamber and the orifice large,
the spray has much more force and capacity.

QUESTIONS

1. What is spra3ring machineiy used for?

2. State some of the important construction features of sprayers.

3. What are field sprayers used for?

4. What adjustment should be provided for a field sprayer?

5. What power is most gen^^y used for power sprayers?

6. Describe the different types of spray pumps of power sprayers.

7. In what different ways is the pump driven?

8. What types of agitators are used for power sprayers?

9. Describe two types of spray nozzles.

Digitized by

Google

CHAPTER XLVII
THE CARE AND REPAm OF FARM MACHINER7

The efficiency of modem farm operations depends pri-
marily upon the successful and judicious use of improved
farm machinery. This fact is generally recognized. No
other ooimtry uses as much machinery as the United
States. The Census of 1910 showed that the American
farmer was annually buying 149,318,544 dollars' worth
of farm machinery. This amoxmt was equal to over 3.3 per
cent of $4,499,319,838, the value of the crops raised. It is
possible at this time to make only a rough estimate of what
percentage of the farmers' profits 3.3 per cent of the value
of crops is.. Perhaps 20 to 30 per cent would not be too large.
Any feature of farm management which absorbs 20 to 30 per
cent of the profits is well entitled to earnest consideration.

Much has been written from time to time about the care-
lessness of the American farmer in caring for his machinery.
Various estimates have been made of the hfe and deprecia-
tion of the more important farm machines. Perhaps, in
many cases, these estimates have been too low; but there
is Httle doubt in the nund of the person who makes only a
casual investigation, that average life of most farm machines
is much less than it ought to be. An investigation on several
farms in Minnesota* indicates the average depreciation of
farm machines to be 7.3 per cent annually. It is to be noted
that this represents the most favorable conditions, since the
farms investigated were well managed.

The care or management of farm machinery readily

^Bulletin 117. Minn. Agricultural Experiment Station.

309

Digitized by

Google

310 AGRICULTURAL ENGINEERING

resolves itself into three heads: repairing, housing, and paint-
ing. Of these, the repair item is perhaps the most important.
The greater part of the average farm machine is not subject
to wear, and, if not broken, ought to last indefinitely. Con-
sidering the modem gang plow, except the share, moldboard,
wheelboxes, and axles, there are comparatively few parts sub-
ject to wear. All of these should be either adjustable or renew-
able at a small expense. The main parts of the plow, the
parts which absorb the greater part of the cost of making,
as the frame and the beam, ought to last indefinitely. Bail
boxes and wheel boxes are easily and cheaply replaced, and,
when renewed, make these parts of the plow as good as when
it left the factory.

Repairing. To repair farm machinery successfully some
system must be used, and the early spring is the time of
year to give thought to this. No doubt many a machine
is taken from storage in the spring, or whenever the machine
is needed, and the owner finds that he has forgotten to
order certain repairs, which, he remembers, were needed at
the close of the previous season. When he proceeds to order
these repairs from his agent, he finds that others have done
likewise; and the agent, the jobber, and the manufacturer
are rushed with orders. There are always delays and short-
ages, which often result in the purchase of new machines,
as those ftoiiliar with the farm industry are aware. U the
necessary parts had been ordered months before, they would
have been secured without fail, and they could have been
put in place on the machine and the machine adjusted and
made ready for work. Repairs for the older machines are
not carried in stock except at the factory, and for this reason
plenty of time must be allowed for filling orders. Again, it
would be a decided advantage to repair the machinery at the
time of the year when work is less pressing. On most farms

Digitized by

Google

FARM MACHINERY 311

some of the "winter months offer a good opportmuty to do
miscellaneous work of this character.

Sjrstem of Repairs. A definite sytem has proven to be
very useful in keeping farm machinery in repair. As each
machine finishes its work for the season and is placed in the
implement house, a tag with a string is taken from a conveni-
ent place and a record is made of the repairs that the machine
needs for the next year. It is much easier to make this record
at that time than later, as everything is fresh in mind. An
inspection of this tag at any time will show just what the
machine needs in the way of repairs. Before the busy sea-
son all the machinery should be gone over systematically,
and the needed parts sent for or repaired in the home shop.

More emphasis should be placed upon the matter of
systematic repairing than upon any other phase of the care
of faito machinery.

Housing. II may be demonstrated that rust is more
destructive than wear. A striking example of this is found
in the harvester. Its average life extends over a certam term
of years, largely independent of whether it harvests 40 or
200 acres of grain each year. Again, we find in machine
shops and factories machinery which has lasted as long as
the harvester and which, instead of being in operation a few
days in a year, is in operation ten hom^ or more day in and
day out without rest.

Wooden parts are affected more by exposure to the weather
than metal parts, but both are materially injured. Not
only is the Uf e of machinery shortened, but its efficiency, the
quality of its work, is lowered by not being carefully protected
from the weather. The average farm requires about $1000
worth of machinery. This may be nicely housed in a build-
ing costing $200, an investment that will pay good divi-
dends in protecting and prolonging the Ufe of the machinery.

Digitized by

Google

812 AGRICULTURAL ENGINEERING

The constraotion of the implement house will be discussed
in a later chapter.

Painting. Painting is simply providing each implement
with a house of its own. Wooden parts deteriorate rapidly
when moisture is allowed to penetrate the surface. Wood
decays and warps, rendering it weak and useless for the pur-
pose for which it is used. Unprotected iron or steel when
exposed to the weather unites with oxygen of the air, or
rusts, gradually giving up its strength. Steel bridges decay
in this manner so rapidly that they must be replaced after
a term of years. To protect these metals, their surfaces are
coated with paint to keep out the moisture and air. Rail-
road companies and large corporations find it profitable to
keep their steel bridges and stuctural work well painted.

Periiaps there is no better paint for implements, not tak-
ing into account a personal dislike which some have for the
color, than red lead and linseed oil. This paint will adhere
well to clean surfaces of wood and iron, and is affected about
as little by the weather as an3rthing that can be used.

Besides prolonging the life of the machines themselves,
a machine dressed in a good coat of paint commands more
respect and is looked upon as being a better machine. The
author can recall specific instances where a coat of paint'
has increased the selling price of machinery fifty per cent
or more.

QUESTIONS

1. How much does the American farmer spend annually for farm
machinery?

2. What percentage is this of his gross and of his net income?

3. What is the average depreciation of farm machinery?

4. Explain why the repair of farm machinery is so important.

5. Describe a system of keeping all farm machinery in good repair.

6. Why is the housing of farm machinery so important?

7. Give several reasons why machinery should be kept painted.

Digitized by

Google

PART SIX— FARM MOTORS

CHAPTER XLVIII
ELEMENTARY PRINCIPLES AND DEFINITIONS

Fann Motors. Farm motors as discussed in this text
include machines which furnish power for operating farm
machinery. In the broadest sense, the term farm machinery
includes farm motors. Owing to a lack of space it will be
possible to consider only such motors as are in general use for
agricultural purposes.

Energy. Energy may be defined as the power of pro-
ducing a change of any kind. It is the function of a motor to
utilize and transform energy in such a way that it may be
used in operating machinery. There are two general forms
of energy: (1) potential or stored energy, like that con-
tained in unbumed coal; and (2) kinetic, or energy of
motion, an example of which is the energy of the wind.

Sources of Energy. The sources of energy which are
made use of by farm motors are feed, fuel, and the wind.
The first two of these represent potential energy and the
last kinetic.

The Most Important Farm Motors. The motors which
are used generally for operating farm machinery are the horse,
the windmill, the gas, gasoUne, or oil engine, and the steam
engine. Other types of motors, such as the water wheel and
the electric motor, are used to a limited extent for agricultural
purposes. All of these motors, with the exception of the
electric motor, are prime movers; that is, they take the energy

313

Digitized by

Google

314 AGRICULTURAL ENGINEERINQ

in the form of food, fuel, or wind and convert it into mechan-
ical energy, which may be used in driving machinery. The
electric motor is driven by electric energy, furnished either
by an electric generator, driven by a prime mover, or by
chemical action, like the electricity from an electric battery.
Forces. A force is that which produces, or tends to pro-
duce or destroy, motion. A force has two
characteristics, magnitude or size, and direc-
tion. The unit by which the magnitude
of a force is designated or measured is the
poimd. The poimd is the action of the force
of gravity on a definite mass. When two or
more forces act at a point their combined
action is equal to the action of one force,
^' called the remUant. In a reverse manner a

force may be divided into components j which act in different
directions from that of the force.

Work. When a force acts through a certain distance, or
when motion is produced by the action of a force, work is
done. Work is often defined as the product of force times
distance.

The Unit of Work. The unit of work is the foot pound,
or the equivalent of the force of one pound acting through a
distance of one foot. Thus, for example, the work done in
raising a weight of one poimd five feet or five pounds one foot
would be five foot pounds.

Power. Power is the rate of work. In determining the
rate of work time is a factor. Thus the measurement of
power consists in determining the munber of foot pounds of
work done in a certain time.

The Unit of Power. The imit of power in coromon use is
the horsepower. It was estabUshed arbitrarily, and is
equal to 33,000 foot pounds of work per minute. Thus if the

Digitized by

Google

FARM MOTORS 31S

product of the force in pounds by the distance in feet traveled

in one minute be 33,000, one horsepower of work would be

done. In measuring horsepower it is customary to determine

the number of foot pounds of work done in a minute and

divide by 33,000. For example, suppose a horse walks 165

feet per minute and exerts a pull of 200 pounds on his traces;

then the horsepower developed will be:

200X165

= 1 horsepower

33,000

QUESTIONS

1. What Is energy?

2. What 18 the function of a motor?

3. Explain the two general forms of energy.

4. What are the principal sources of energy?

5. Name the most importanii farm motors.

6. What 18 a prime mover?

7. What 18 a force?

8. How may a force be illustrated?

0. Illustrate resultant and component forces.

10. Define work.

11. In what units is work measured?

12. Define power.

13. What is the oonmion unit of power and what is its equivalent?

Digitized by

Google

CHAPTER XLIX
MEASTTREMENT OF POWER

The Necessity of Measuring Power. The cost of power
is one of the largest items in the cost of performing farm
operations. In general, operating costs on modem farms can
be readily divided into the cost of labor, of power, and of
machinery. It is desirable to keep each of these items as low
as possible, as long as it will make the total cost lower. Of
these three items the labor and power costs are by far the
largest, and it is desirable that every farmer be able to ana-
lyze them carefully. In order to determine the cost of power
accurately, it is necessary to know how the power furnished
by different motors may be measured and compared.

Quantities Which Must Be Determined. Power has
aheady been defined as the rate of work. Then in measiuing
power it is necessary to determine the amount of work done
in a certain length of time. Thus the problem is simply a
matter of determining these three quantities, the force, the
distance, and the time.

Measuring the Power of an Engine. The power of an
engine is commonly measured by applying a so-called Prony
brake to the pulley or fly wheel. This brake increases the
friction until the entire power of the engine is required to
rotate the fly wheel or pulley within the brake when held
stationary. By allowing the arm of this brake to rest upon a
scale, the force required to move the pulley or wheel within
the brake is foimd.

The distance traveled in one minute by this force as
measured by the scale is equal to the circiunf erence of a circle

316

Digitized by

Google

FARM MOTORS

whose diameter is twice the length of the brake arm, times
the number of revolutions made by the engine in a minute.
Thus it is seen that it is not difficult to make a simple test of

Pig. 197. The Prony brake as applied to the pulley of an engine to
measure the power (From Farm Machinery and Farm Motors).

an engine. All that is needed is a brake, a scale for measur-
ing the force, a speed indicator or revolution counter, and a
watch to determine the revolutions per minute.

The distance per minute multiplied by the force as indi-
cated by the scale gives the number of foot pounds of work
done in one minute, and this divided by 33,000 gives the
horsepower. Stated in the form of a formula it is as follows :

H.P.=

net load on scale X 2 X length of brake arm
(in ft.) X 3.1416 X rev. per min.

33,000

Dynamometers. A dynamometer is an instrument used
in measuring power. The Prony
brake referred to above may be^
called an absorption dynamome-
ter, in that in the measurement
the power is used up by friction.
A dynamometer which measures ^^* triJtion dynam'omVtS^*"*

Digitized by

Google

818 AGRICULTURAL ENGINEERING

the power while still allowing it to be used in driving the
machine is called a transmission dynamometer. Instru-
ments used for measuring the draft of implements in the
field are called traction dynamometers. Those which simply
indicate by a needle and dial the draft or force required

Fig. 199. A recording dynamometer as designed by the Agri-
cultural Engineering Section of the Iowa Agr. Exp. Station.

to move the implement are called indicating or direct^eading
dynamometers. One provided with rolls of paper operated
by clock mechanism or by a wheel in contact with the ground,
over which a pencil moves and records the draft, is said to be a
recording dynamometer. There are also a few kinds on the
market which average the draft over a measured run.

QUESTIONS

1. Why is an understanding of the measurement of power im-
portant?

Digitized by

Google

FARM MOTORS 819

2. What quantities must be determined in the measurement m
oower?

3. Describe in detail how the power of an engine is measured.

4. Explain the formula for calculating horsepower.

5. What is a dynamometer?

6. Describe an indicating dynamometer.

7. How is a dynamometer made a recording instrument?

Digitized by

Google

CHAPTER L
TRANSMISSION OF POWER

Not all machines can be so placed as to be driven directly
by the motor, and so there must be some means of transmit-
ting the power to the machine.

Belting. One of the most common forms of transmitting
power from one rotating shaft to another is by belting. In
this case the power is transmitted by the friction between the
belt and the pulley, producing rotation. While transmit-
ting power a belt is under greater tension on one side, the
"tight side," than on the other, or "slack side." The actual
force transmitted is equal to the difference in the tension of
the "tight side" and the "slack side." The power trans-
mitted depends also upon the speed of the belt or the distance
the force travels in a given time.

Horsepower of Belting. In installing a power plant of
any sort in which belting is used, it is necessary to determine
the size of belts which will transmit the desired amoimt of
power. A formula quite generally used in estimatii^ the
horsepower of leather belts is as follows:

V X w

H. P. =

1000
where H. P. equals the horsepower; V the velocity of the belt
in feet per minute; and W the width of the belt in inches.

If the speed of the driving pulley, which furnishes power,
and its diameter be known, V may be easily obtained by
multiplying the circumference of the pulley in feet by the
revolutions per minute. A belt should seldom travel more

320

Digitized by

Google

FARM MOTORS 321

than 4000 feet per minute, and 2000 feet is a more common
velocity.

Leather Belting. Leather is the standard material for
belting and is considered the most durable, when protected
from heat and moisture. A good leather belt should last
from ten to fifteen years when used continuously. It is
customary to run the belt with the grain or smooth side next
to the i)ulley, as the strength of the leather is largely centered
in this side of the belt; if run with the smooth side out it is
quite likely to become cracked.

In order that leather belts should render good service they
should be properly cared for.
As a belt bends, the fibers of
the leather slip over one an-
other, and for this reason belts
should be oiled or lubricated.
Neatsfoot oil is the standard
oil for this purpose. There are
many good belt dressings on
the market, but there are oth-
ers which are decidedly inju- ^'^- ^e^/anSTathe^ rur„V"''
riQus. A leather belt works best

when phable enough to adhere closely to the pulley ,^ and
rosin and other such materials are to be avoided.

Rubber Belting. Rubber belting is made of canvas
thoroughly covered with rubber. It is made in thicknesses
of two-ply and up, three- and four-ply being conmion thick-
nesses. A rubber belt operates quite satisfactorily imder
wet conditions.

Canvas Belting. Canvas belting consists of several thick-
nesses of canvas, four- and five-ply belts being the most com-
mon. The canvas is thoroughly stitched together and then

filled with oil to keep out the moisture, and finally painted.
11—

Digitized by

Google

322

AGRICULTURAL ENGINEERING

The canvas belt is the most economical in cost and is very
strong. It lengthens and contracts, however, with moisture
changes; hence is not suitable for pulleys at fixed distances.
Canvas belting is used largely in connection with agricultural
machinery, being almost universally used in driving threshers
and similar machines.

Lacing of Belts. The common practice of splicing belts
is by means of a rawhide thong, often called a belt lace.
Holes are punched at about five-eighths
inch from each end of the belt and oppo-
site each other. In order to give greater
strength, two rows of holes are often
pimched, the second row being set back
farther from the end of the belt. The
accompanying illustration shows a
A good good style of lacing. The lace on the
side next the pulley should not cross
diagonally from one hole to another, but should extend
directly across the splice.

Where the belt is to pass around an idler and thus be com-
pelled to bend in both directions, the hinge lace is most satis-
factory. There are many forms of patent belt splices and wire
lacing on the market, some of which are quite satisfactory.
Several forms permit the ends of the belt
to be separated by removing a rawhide
pin which is held in place by the lace.

Pulleys. Pulleys on which belts run
are made of wood, cast-iron, or steel.
Wooden pulleys are made in halves,
arranged to be easily clamped to the
shaft. Cast-iron and steel pulleys are
sometimes made in the same manner.

Wooden pulleys are the cheapest and are very conven

Fig. 201.
way to lace a belt.

Fig. 202. A wooden
pulley.

Digitized by

Google

FARM MOTORS 323

ient to attach, but are not so durable as those made of metal.
Metal pulleys are sometimes covered with leather in order to
increase the friction of contact with the belt. Pulleys from
which belts are not to be shifted should have a crowned
face. This will cause the belt to keep in the center of the
pulley, owing to the fact that the belt
always tends to run to the highest part
of the pulley. The pulley which supplies
the power is generally spoken of as the
driver, and the one receiving the power is
designated as the driven pulley.

Calculating the Speed. It is an easy mg. 203. a piain
matter to calculate the speed or the diam- c*s^-*''on puiiey.
eter of the pulley, when it is remembered that the diameter
of the driving pulley multiplied by its revolutions per min-
ute is equal to the diameter of the driven pulley multipUed
by the number of its revolutions per minute. If any three
of the four quantities involved are known, the fourth may be
easily obtained.

Link Belting. A conmion method of transmitting power

in agricultural machinery is by means of

link belting running on sprockets. Link

belting is positive in its action, as there

can not be any slippage. It is very strong,

but its use is often objectionable on account

of the noise which it makes and because

Fig. 204. A split it cannot be operated at high speed.

iron pulley. There are several styles in use; in some

the links or sections are made of malleable iron, and in

others of pressed steel. Again, some expensive chains are

made of steel rollers with short steel links riveted on the side.

Rope Transmission. Where power is to be transmitted

some distance and where the shafts are not parallel

Digitized by

Google

824 AGRICULTURAL ENGINEERING

ropes running over grooved pulleys or sheaves may be used
to good advantage. Cotton or Manilla ropes are used

for this purpose. These
grooves are arranged so
as to cause the rope to
wedge in, thus increasing
the effect of friction.

Wire Rope or Cable
Transmission. Where
power is to be transmitted
some distance, as from
one building to another,
wire cables can be used to
good advantage. The pul-
ley grooves should not
wedge the wire rope, but
instead should have a rub-

Vlg. 205. An example of the trana- , nu i.« i. xi_

mission of power by ropes and shafting. Der tiller OU WlUCn tnC
AAA are hangers. ^^^^ ^^^

Triangles or Quadrants. The power from a windmill may

be transmitted to a distant pump ^j ^

by the use of triangles or quad- I7*"^i "1 "

rants, as shown in Fig. 206. If j>C— —
the wires are long they are sus-
pended on rocker arms.

Gearing. A very common
method of transmitting power in
agricultural machinery is by means _ «.. „ ,

^ . . - Fig. 206. Triangles or quad-

Of gearing. The construction of rants used in transmitting

the teeth is a matter of careful

design, since they must be made to run smoothly together.
In cast gears the teeth are cast to shape, while in cut gears
they are machine made. Cut gears are generally more per-

l^,

Digitized by

Google

FARM MOTORS 325

feet, but are more expensive. Gears with parallel shafts
are called spur gears; those with shafts at
an angle are bevel gears.

Gears transmit power positively, as
there is no slippage. A snudl gear wheel
in mesh with a large one is often spoken of p,^ aoTTpur gear-

§iSi A ryininn ****• T^® pinion or

Friction Gearing. Friction gearing ^^«^^ ^ "shrouded."
transmits power by the friction of two surfaces in contact.
The face of the driven pulley is usually of cast-iron, and that
of the driver is of paper or rawhide. Fric-
tion gearing is often used where the slip-
page is desirable to prevent breakage or to
start heavy loads.

Shafting. Power may be transmitted
from one point to another by means of
a round shaft, to which pulleys, sprock-
ets, or sheaves may be attached. This
Fis. 208. Bevel shaftiug is usually supported
ge&ring. by hangers carrying bearings.

Collars or rings are attached to the shaft to
keep it in place. The supporting hangers
should be near the pulleys, or at such short
intervals as to prevent excessive vibration of
the shafting while running. Usually the hang-
ers are placed from six to eight feet apart.
The power which the shafting will transmit

depends upon the material and the revolutions

per minute, and varies directly with the third ^^^'ie&riTg^^
power of its diameter.

A common formula for the horsepower of the shafting is :

H. P. =

Digitized by

Google

326 AGBWULTUBAL ENGINEERING

where H. P. is the horsepower transmitted, D is the diameter of the
ahaf ling, and R is the number of revolutions per minute.

The above formula is for cold rolled steel shafting, the
kind in general use.

QUESTIONS

1 . Why is a study of the transmission of power
an important feature of the study of machinery?

2. How is power transmitted by a belt?

3. What is meant by "tight" and "slack"
sides of the belt?

4. Give the formula for estimating the horse-
power capacity of a leather belt.

6. For what conditions of service is leather
Fig. 210. Friction belting adapted?

grearing. ^ Describe the care of leather belts.

7. For what kind of service is rubber belting best? Canvas?

8. Explain how a belt should be laced.

9. Describe the various kinds of pulleys in general use.

10. Why are some pulleys crowned?

11. Explain how the rotative speed of one pulley may be obtained
from another.

12. Where may link belting be used to good
advantage?

13. What kinds of ropes are used in rope
transmission?

14. Under what conditions should a wire Figr. 211. a Unk belt

, , , JO or chain transmissions.

rope or cable be used?

15. How may triangles be used to transmit windmill power?

16. What is the difference between cut and cast gears?

17. Describe the construction and action of spur gearing.

18. Give the formula for the horsepower capacity of shafting.

Digitized by

Google

CHAPTER LI
THE HORSE AS A MOTOR

Power from Horses. The horse is the principal source of
power for agricultural purposes, and will continue to be for an
indefinite length of time. Considered in the aggregate, the
horse and the mule furnish a large part of the total power
utilized for all purposes. In the United States there are
at the present time approximately twenty-one million head of
horses and mules. The nimiber has been increasing for the
past sixty years at the rate of one-third million annually. If
all these were at work at one time, power to the amount of
twelve to fifteen million horsepower would be developed.

Development. The prehistoric horse was not a large
imimal; but nature and man, by careful mating and selection,
have produced different types, each suited for a special pur-
pose, until the modem horse bears but little resemblance to
the original. As early as 1740 B. c. the horse was used in
war for transportation. It was not until about the year
1000 A. D. that history records the use of the horse in the field.

The development of the horse has necessarily been very
slow. Greater hardiness, increased size and strength,
greater beauty, and other desirable characteristics were rec-
ognized by men who made careful selections for mating and
awaited results.

The horse has been called man's best friend in the brute
world, and the ownership of a good horse is something that
any man can be proud of. Notwithstanding the fact that
the horse is an animated thing, it is the chief source of power
on the farm, and may properly be considered a motor. It

327

Digitized by

Google

828 AGRICULTURAL ENGINEERING

differs from all mechanical motors ii\ that it is self-feeding,
self-controlling, self-maintaining, and self-reproducing.

Classification. The horse in one sense is a heat motor,
burning fuel in the shape of feed, and as such is a prime mover.
The thermal efficiency of a horse exceeds that of an average
steam engine, but does not equal that of a gas or internal-
combustion engine.

Capacity of the Horse. The amount of power that a horse
can develop depends largely upon its size and muscular devel-
opment. Experiments indicate that a horse exerts a pull on

Fig. 212. Testing the draft of a horse. Also studying the effect of
the height and length of the hitch.

his traces equal to from 1-10 to 1-8 of his weight when the
working day is not allowed to extend over eight to ten hours.
The speed at which the horse is able to produce the largest
day's work is from 2 to 23^ miles per hour. Thus a 1500-
poimd horse walking 23^ miles per hour and exerting a pull
of 150 poimds, will develop one horsepower; and, furthermore,
he will be able to continue this for a period not longer than 10
hours. An increase in the rate of travel, or an increase of
the effort or draft, must result in a corresponding decrease in
the length of the working day.

Digitized by

Google

FARM MOTORS 329

Maximtiin Capacity of the Horse. The maximum effort
of the horse for a short time may exceed his own weight. In
an actual test a horse weighing 1550 pomids and pulling on
traces at an angle of 27 degrees with the horizontal exerted a
pull of 1750 pounds. A draft horse may exert an effort of
about one-half his weight while walking at a speed enabling
him to develop, for a short time, as much as four or five horse-
power. Such trials must be of short .duration and be followed
by periods of rest.

The fact that the horse is such a flexible motor, being able
to develop power much in excess of the normal rate, is cer-
tainly a great advantage for traction pmposes, where the load
is constantly changing because of the condition of the surface
and the varying grade. Yet this fact often accounts for a
serious overloading, resulting in an injury to the horse.

Amount of Service. The horse on the farm does not do
continuous labor. Investigation in Minnesota indicates that
the average farm horse does not labor for more than 1000
hours per year. The useful life of a horse is usually regarded
as ten years.

The Size of Teams. A well-trained horse will direct his
effort at the command of his master; yet the manageable
team for field work cannot well exceed foiur horses. A capable
driver can drive a four-horse team practically as well as a two-
horse team and manage almost any of the implements requir-
ing four horses. It is true that larger teams than four horses
are in use, but the diflSiculty connected not only with the
drivmg but with the harnessing and hitching will likely pre-
vent any general increase of the size of the field team beyond
four horses. As many as 32 horses have been driven by one
man, but the assistance of several others is required in har-
nessing and hitching. In driving these large teams, which
are used principally on the combined threshers of the large

Digitized by

Google

330 AGRICULTURAL ENGINEERING

farms of the West, the whole team is controlled largely by the
two leaders. Thus, if a 24-horse team is to be made up, the
two leaders will be followed by four horses abreast and these
by the others arranged six abreast.

The Principles of Draft. Although horses have been
used as draft animals since the dawn of history, it is strange
to note that the principles of draft are not clearly understood,
many points being open to argument. The individual
horse owner has not felt justified in making exhaustive experi-
ments for his own benefit, and no professional experimentalist
has found it possible to give the matter attention. Mr. T.
H. Brigg, of England, who studied the subject of horse haul-
age, states that on an average the horse is made to waste as
much as 50 per cent of his energies. In farm practice this
would evidently not be true; yet, if it is only partly true, the
horse offers a fertile field for profitable investigation.

The amount of resistance that a horse can overcome, or
the draft that he can exert, depends upon several factors; viz.,
his weight, height, and length, his grip upon the road smf ace,
his muscular development, and the direction of the traces.

Weight. A heavy horse has several important advan-
tages over a Hght one. In the first place his adhesion to
the road surface is better, — ^there is less tendency for him to
shp; and, in the second place, with the heavy horse there is
less tendency in pulling to lift the forefeet from the ground.

Height and Length. The latter point also indicates the
advantage that a long-bodied horse has in pulling. The
height of the horse may or may not be to his advantage,
depending upon the height of hitch. It is common occur-
rence to see the efforts of a horse limited by his weight and
length, as his forefeet are lifted from the ground without
permitting him to exert his full strength. It is an easy matter
to demonstrate that a horse can increase his maximum

Digitized by

Google

FARM MOTORS 331

effort about 200 pounds by having a man sit astride hi?,
shoulders. Experienced teamsters with light teams often
make use of this method of assistance in an emergency pull.

Grip. The grip of the horse refers to the hold that he
secures on the surface of the road or ground. Thus, for
example, it is obvious that a horse without sharp shoes could
pull but little on ice. In like manner the horse is often
unable to obtain a sujficient hold on hard ground or pavement
to exert his full strength.

Muscular Development. It is necessary that the horse
have large and powerful muscles, for these are really the
motors that do the work. The object of the breeder of draft
horses has always been directed toward the development of
the muscles as well as the increase in size.

The Proper Angle of the Traces. The proper direction
or angle of trace is a question on which there is much differ-
ence of opinion. In fact there are two phases of the subject;
first, the angl« of trace with which the horse will labor with
the most comfort and ease; and second, the angle of trace
which will move any load with the least force. The first of
these is the most diflSicult to study. If the horse can reahze
that certain positions of the hitch, the trace, and the collar are
most comfortable, he cannot tell his master so. The angle of
trace has a very decided effect upon the maximum effort of a
horse. A low trace has a tendency to pull the horse into the
surface, thus adding to his adhesion and grip and overcoming
to a considerable extent the tendency to Uft the forefeet from
the ground. It is undesirable to maintain a low trace con-
tinually, because the horse is compelled to carry more or less
of the load when less effort would be required to draw it.
For maximum speed it may be desirable to carry a part of
the horse's weight on the truck, and the racing sulky, whether
purposely or not, is arranged to do so.

Digitized by

Google

832 AGRICULTURAL ENGINEERING

Referring to the angle of trace for the mimmum draft, it
is to be recognized that there are two distinct classes of imple-
ments to which horse labor is applied: (1) those intended
primarily for moving heavy weights from place to place;

and (2) those designed to work

the soil. In the first case the draft

\ is due chiefly to the friction of

\ • the machine and the rolling or

\ sliding resistance of the surface.

\ Thus, in Fig. 213, it is to be noted

+— 3g^^ that a certain force, TT, will lift

l^^^pl^jf iS¥ y^ the block, A, and another force,

{/ F, will slide it on the surface.

*^ the angle of ^ least draft "* The Icast forCC, hoWCVCr, that will

produce motion Ues between
these two, as D, and its direction depends upon the magni-
tude of each of the other two forces. In mechanics the
angle this force makes with the horizontal is called the angle
of repose. If the load is to be drawn up an incline, the
proper angle of trace should equal the ordinary angle plus
the angle of the grade. With an implement like the plow, the
line of least draft extends almost directly to the center of the
place where the work is being performed.

The Length of Hitch. Lengthening the hitch does not
have the effect that it is generally supposed to have. The
principal effects are that the horse does not have as complete
control over the load and that the angle of trace is changed.
Lengthening a horizontal trace ten or even fifty feet has
practically no effect upon the capacity of the horse. Men
are often found who think they can hold a horse at the end of
a 50- or 100-foot rope. A trial is very convincing that they
cannot do so.

Digitized by

Google

FARM MOTORS 333

QUESTIONS

1. Why is the horse the principal source of farm power?

2. To what extent has the horse been developed as a farm motor?

3. In what way does the horse differ from mechanical motors?

4. What kind of motor is the horse?

5. What relation is there between the weight of a horse and the
power it can develop?

6. How does an increase in the speed or length of working day
affect the power of the horse?

7. To what extent can a horse deliver power in excess of the nor-
mal rate?

8. How many hours of service does an average farm horse render
in a year?

9. Explain how horses may be arranged in large teams for heavy
loads.

10. Upon what factors does the amount of resistance a horse can
overcome depend?

11. How does the height and length of a horse affect the resistance
he can overcome?

12. What is meant by a horse's grip?

13. Explain the importance of muscular development in a draft
horse.

14. Discuss the influence of angle of trace on draft.

15. Why is the angle of least draft not always best?

16. How does the length of hitch affect the resistance a horse can
overcome?

Digitized by

Google

CHAPTER UI
EVENERS

The use of four- or five-horse teaiyis, as now required for
many implements, introduces many perplexing problems in
connection with the hitch and the eveners for dividing the
work evenly among the animals. In addition to the increase
in the size of teams used with gang plows, disk harrows, drills,
harvesters, etc., the tongue truck and the complicated patent
evener have been introduced, which add to the difficulty of
understanding the mechanics involved.

There is Uttle difficulty in dividing the load equally
between the members of a two-horse team. The doubletree
may be of any reasonable length, depending on whether it
is desired to wof k the horses close together or to spread them.
To divide the work equally between two horses, the end
holes for attaching the singletrees should be equally distant
from the center hole. The wagon doubletree is usually 44
inches long, and the plow doubletree 30 inches. Large horses
cannot be worked as closely as smaller ones. It is undesir-
able to work horses too closely, as all are worried more or less
by not having sufficient room.

The Placement of Holes. When the horse is pulling on
the end of an evener, his advantage or leverage is equal to
the perpendicular distance between the extended line of
draft and the Une of resistance passing through the center
hole, or the fulcriun, of the evener. This is illustrated in
Fig. 214. If all the holes in the evener are in line, it makes
little difference whether or not it is kept at right angles to
the direction of movement. If the center hole is not in line

334

Digitized by

Google

FARM MOTORS

335

with the two end holes, then the load is divided evenly only
when the two horses pull evenly together. If one horse pulls
in advance of the other, the load is no longer evenly divided.
It is customary to place the end holes well toward the rear
edge of the evener, and the center hole well toward the front
edge. This placement of the holes adds materially to the
strength of wooden eveners.

When the holes are much out of line and when the horses
do not pull evenly, there may be much difference in the efforts
of each. In Fig. 214, which shows a wagon doubletree as

r-t z'^' v^^—

Fig. 214. A wagron doubletree Illustrating the effect of not having the
holes for the clevis pins In a straight line.

actually manufactured, the rear horse would be compelled
to pull 18.9 per cent more than the leading horse, with one
end of the doubletree 16 inches in advance of the rear end.

Three-Horse Eveners. In order to divide a load among
three horses, it is necessary to introduce a second lever, or
some other device to take its place. A usual method of
arranging such an evener is shown in Fig. 217. This is a
combination evener, which in this instance does not space the
horses evenly but indicates the general arrangement of the
three-horse evener, or tripletree. The factory-made triple-

Digitized by

Google

33€ AGIUCULTURAL ESODiSBRDfG

tree usoalty has diort metal krers pbced over a wooden
eveneTy as ilhistrated in Fig. 215. This gives the advantage
of a shelter hitch. A shiMrter hitdi will not cause an appre-

FIC. SIS.

daUe reduction of the draft, but will ooaUe the team to
have betttf contool ow the imptoneni.

Foor-» Ft?e-» and Siz-Hocse Evenefs. The four-horse
even^ is usually made as illustrated in Fig. 217. This con-
sists in a four-horse evai^r with two doubletrees attached.

The plain five-horse eveno* is made as shown in Fig. 216.
The dimensions gi voa are ri^t for medium-sixed horses when
it is desired to work them togetho* as doeely as practical.

There has been a decided increase in the use of the 14-inch
gang plow during recent years. This plow makes a load too
heavy for four average horses, and five or six horses should
be used. It is undesirable to work five horses abreast, for,
if one horse walks in the furrow and the other four on the land,
the load or line of draft does not come directly behind the
center of the team and there will be much undesirable side
draft. It is better to put two horses in the lead and use

Fig. 216. A plain flve-horae evener.

eveners such as those shown in Fig. 217. This yriH put the
team directly in front of the load and yriH avoid the side draft.
Instead of the short levers placed under the rear doubletree

Digitized by

Google

FARM MOTORS

337

to equalize the draft between the leaders and the two horses
directly behind them, a short, vertical evener of metal or a
chain and pulley may be used. In the case of the five-horse
evener, the end hole for the single horse hitch should be
foiur times as far from the center hole of the evener as the end
hole for the four horses working in pairs. In case of the six-
horse evener, the hitch for the team should be twice as far
from the center hole as the
hole for the foiur-horse
hitch.

Plain Eveners. Simple
or plain eveners are much
to be desired. There is
absolutely nothing to be
gained by a complicated
system of levers and tog-
gle joints. If there is to
be an equalization of the
draft, there should be a
flexible hitch; and if the
evener is attached to the
plow or other implement
at more than one point, the hitch cannot be truly flexible.

Overcoming Side Draft With four horses hitched
abreast, on a sulky plow the line of draft lies outside of the
line of resistance, and there is a tendency to throw the front
end of the plow away from the land. This tendency can be
partly overcome by adjusting the front furrow wheel in such
a manner as to pull the plow toward the unplowed land, as
previously discussed. (See page 203.)

The tongue truck is the only satisfactory means of off-
setting draft, and for this purpose it is a commendable device.
The truck should be provided with heavy flanged wheels

Fig. S17. A combination three-,
five-, and six-horse evener.

four-,

Digitized by

Google

838

AGRICULTURAL ENGINEERING

which will engage the surface of the ground and give a thrust
directly across the line of draft. This arrangement, no
doubt, adds a little to the draft, but it adds much to the con-
venience of handling the team, especially on the harvester.
When three horses are to be hitched to an implement with
a tongue attached in the line of draft, much may be accom-
pUshed by crowding the two horses on one side of the tongue

as closely together as pos-
sible and putting the sin-
gle horse out as far as
possible.

Fig. 218 shows an at-
tempt described in an
agricultural paper some
time ago as a successful
method of overcoming side
draft on a disk harrow
with two horses on one
side of the tongue and one
on the other. The chain pulls back precisely the same
amount that it pulls the one side of the disk harrow ahead.

Fig. 218. A futile attempt to remove
side draft when the team is not placed
directly in front of the load. An offset
tongue should be used.

QUESTIONS

1. Why is it more important to study eveners now than formerly?

2. How closely should horses work?

3. Explain how the placement of the clevis holes of a doubletree
may influence the distribution of the load.

4. Describe the construction of three-horse eveners.

6. Explain how an evener may be arranged to hitch five or six
horses to a plow.

6. Why are simple or plain eveners desirable?

7. What is the best way to overcome side draft?

8. Why is it not possible to remove side draft by running a chain
across a machine?

Digitized by

Google

CHAPTER LIII
WINDMILLS

Utility. The windmill is adapted to work which may per-
mit of a di&continuanee during a period of calm. It is
adapted to regions where wind of a velocity sufficient for its
operation prevails generally throughout the year. One Une
of work which will permit of a discontinuance during calm is
pumping, and for this reason the use of the windmill is con-
fined largely to this work.

When properly installed and working under proper condi-
tions, the windmill is perhaps one of the most economical of
all motors. As a source of energy it costs nothing; the cost
of the power is due solely to the interest on the investment
and to depreciation and repairs.

Development. The use of windmills dates back to a
very early time. Wind and water wheels were used as the
first source of power long before heat engines were thought
of. The windmill years ago reached a rather high stage of
development in Emx)pe, those of Holland being especially
famous. The Holland or Dutch mills represent a distinct
type, in that there were usually four canvas sails mounted on
a wooden frame. The speed was regulated by varying the
amount of sail surface exposed to the wind. In most cases
the mill was turned toward the wind by hand. The steel
windmill was developed in the United Stated about 1883.

The Wind. Wind is simply air in motion. It represents
kinetic energy, and the windmill obtains power from it by
reducing its velocity, causing a certain amount of energy to

339

Digitized by

Google

340 AGRICULTURAL ENGINEERING

be given up. It is easy to see that it would be impossible to
reduce the velocity to zero and obtidn all of the energy of the
wind, because it must flow past the windmill.
' Types of Mills. There are many types of windmills on
the market, and they may be classified in several ways: (1)
by the material used in construction, (2) by the type of con-
struction, and (3) by the use to which they are put. For-
merly the wheels were made almost entirely of wood, but
steel has now practically displaced wood. It is clfdmed by
good authorities that the steel wheel is more efficient and
will operate in a lighter wind than the wooden wheel, owing
to the thinness and the shape of the fans. Windmills may
be also either direct-stroke mills or geared mills. Direct-
stroke mills are used solely for pumping purposes; a stroke is
made with each revolution of the wind wheel. In order to
produce a mill which will operate in Ughter winds, gearing is
often used to reduce the number of strokes in proportion to
the number of revolutions of the wheel. Most steel mills are
now geared in this way.

Windmills used solely for pumping are called pumping
mills, and the power is transmitted from the wind wheel by
means of a pumping rod having a reciprocating motion.
When a rotating motion is desired a vertical shaft is run from
the mill to a point from which the power may be transmitted
to a machine by any of the more usual methods. Such a mill
delivering its power by a rotating shaft is said to be a power
miU.

Size of Mills. The size of windmills is indicated by the
diameter of the wheel. Common sizes used for pumping
purposes are 8- and 10-foot wheels. Power mills are often
built much larger, with wheels 20 or more feet in diameter.
Wheels of large diameter must be made very strong to be
able to withstand the wind, and the extra weight thus

Digitized by

Google

FARM MOTORS 341

required tends to reduce the eflBiciency. Especially large
windmills have been attempted, but they have not been
successful.

Construction. The most important points involved in the
construction of a windmill are the strength and the rigidity
of the wind wheel and the durabiUty of the bearings and gears.
The wheel must necessarily be light, yet it must be carefully
constructed or it will not be able to withstand the strenuous
service imposed upon it. The bearings should be large, of
material that resists wear, and be easily replaceable. The
gearing should also be of liberal dimensions.

Lubrication. One of the most important features of the
windmill is provision for adequate lubrication by means of
magazine oilers or lubricators, one filUng of which will supply
sujficient lubrication to last for a month or more. Many
mills are destroyed by failure to give them attention in this
respect. Some makers have tried to provide roller bearings
which will not be seriously damaged when adequate lubrica-
tion is not provided.

Regulation. All windmills must have some means of reg-
ulating the speed. One common method. is to have a small
side vane that turns the wind wheel edgewise to the wind as
the velocity of the wind becomes high. .Another plan is to set
the wheel to one side of the center of the mast on which it is
mounted, when the unequal pressure tends to turn the wheel
away from the wind. Again, windmills have a tendency to
turn around on the mast as the rotating speed increases, and
this tendency is made u^e of in regulating speed. In some
wheels the sections are hinged and are connected with a
centrifugal governor which allows them to be turned par-
tially out of gear as the wind velocity increases.

Power of Windmills. One authority concludes that the
power of a windmill increases as the cube of the wind velocity

Digitized by

Google

342

AGRICULTURAL ENGINEERING

and also as the square of the diameter of the wheel. A later
investigator found that the power varied more nearly as the
square of the wind velocity and about the 1.25th power of
the diameter of the wheel. The following table, reproduced
from the work of Mr. 'E. C. Murphy, indicates in a general
way the amount of power furnished by diflFerent kinds of mills
under different conditions.

Power furnished by windmills under different conditions.

Name

Kind

Diameter
in feet

Number of
sails

Velocity of

wind in

miles per

hour

Horse-
power

Monitor

wood
wood
wood
steel
steel
steel

22.5

96
102
100-144
18
21
32

20
20
20
20
20
20

.357

Challenge

Halliday

.420
.89

Aennctor

Ideal

1.05
.606

Perkins

.609

Towers. Like the windmill proper, the tower may be
built either of wood or steel. With the increase in the cost
of wood the steel tower has come into more general use. The
usual height of tower for a pumping mill varies from 20 to
60 feet. The wooden tower usually has four posts made of
4x4 or 5x5 material. The steel tower is made up of three or
four posts of angle irons. The steel tower is now almost
universally galvanized for protection against corrosion. This
is also true of the steel windmill. It is desirable to have the
wheel placed well above all obstructions to the wind, in the
way of trees, buildings, or embankments. A small wheel
on a high tower is regarded as better than a large wheel on a
lower tower which does not permit the wind to reach the
wheel with full force.

Digitized by

Google

it?

FARM MOTORS 343

QUESTIONS

1. To what kind of service is the windmill adapted?

2. Is the windmill an economical motor?

3. How long has the windmill been used?

4. How does the windmill obtain power from the wind?

5. Can the windmill obtain all the energy of the wind which strikes

6. How may windmills be classified?

7. What is the difference between a direct-stroke and a back-
geared mill?

8. To what uses may a power mill be put?

9. How is the size of a windmill designated?

10. What are some of the important features of the construction
oi a windmill?

11. What special provision for lubrication may be provided?

12. Describe how the speed of a windmill may be regulated.

13. How does the power of a windmill vary with the diameter of
wheel?

14. How does the power of a windmill vary with the wind velocity?

15. Describe the construction of the windmill tower.

Digitized by

Google

CHAPTER LIV

THE PRINCn>LES OF THE GASOLINE OR OH.

ENGINE

Relative Importance. The general introduction of the
gasoline or oil engine to do certain classes of work on the farm
places it next to the horse in importance among the various
farm motors now in use. So general has become its intro-
duction and so varied its uses that it is now imperative that
every farmer be familiar with the principles of its operation
and the essentials of its successful management.

Classification of Motors. The gasoline or oil engine is a
heat engine, since its fimction is to convert heat or heat
energy, liberated by the combustion of gasoline or oil, into
mechanical energy. With this respect it is to be classed
with any motor using fuel of any sort.

The gasoline or oil engine is an internalraymbustion engine
or motor, in which the fuel, along with a sufficient amount of
air to support combustion, is ignited inside of a closed cylin-
der. The steam engine might be styled an external-combus-
tion engine, in that the combustion takes place outside of the
boiler or vessel withholding the pressure produced. In the
internal-combustion engine the heat released causes an
increased pressure of the gases in the cylinder, including the
products of combustion, which push upon the piston and
cause it to move forward, allowing the gases to expand and
do work.

Fuels. The gasoline or oil engine does not differ essen-
tially from the gas engine, the diflFerence consisting primarily
in a device called the carburetor, provided to convert the

344

Digitized by

Google

FARM MOTORS

liquid fuel into a gas. Kerosene and fuel oils are more diffi-
cult to vaporize, or gasify, than gasoline, and for that reason
a special carbiu-etor must be provided when they are used;
but in other respects the kerosene
or fuel oil engine does not diflFer es-
sentially from the gasoline ei^ne.
For this reason it is entirely cor-
rect to speak of all internal-com-
bustion engines burning either gas
or liquid fuels after this manner as
gas engines.

The gas engine is very simple,
more so, in fact,
than the steam
engine. The
accuracy with
which the va-
rious functions
must be perform-
ed is the only thing which prevents the
gas engine from being a simple affair to operate.

Types. There are two general types of gas engines on the
market. These are known as the two-cycle and the four-
cycle engines. It is perhaps more proper to style these types
as the two-stroke cycle and the foiu'-stroke cycle, inasmuch as
two and four strokes of the piston are required to complete
the cycle in each type, respectively.

A cycle is a term used to designate a complete set of
operations which must take place in every engine to enable it
to do work. Theapplicationof work or the Uberationof energy
in the gas engine is intermittent. This is true of all recipro-
cating motors, but more operations are required in the gaso-
Une engine than in the steam engine. The four-stroke cycle

Fig. 220. A kero
sene carburetor in BeC'
tion. One of the noz
zles is for water.

Figr. 219. A gasoline car-
buretor. The grasoline is
vaporized by the air as it is
drawn past the nozzle.

Digitized by

Google

346 AGRICULTURAL ENGINEERING

ei^ne is the more simple to explain of the two types and, for
that reason, should be considered first. It is to be assimied
that the reader imderstands the gas engine to consist of the
essential parts as illustrated in Fig. 221. These parts, as
far as a consideration of the cycles is concerned, consist of a
cylinder with a gas-tight piston attached by a connecting rod
to a crank on which the fly wheels and pulleys are attached,
and two valves, an inlet valve to let the gases into the

mr^r^_ -^-^^z::::© •'^^^^©- -•-=-==::^

1st stroke 2Dd Stroke 3rd Stroke 4th Stroke

(Suction) (Conpreeiioa) (Expansion or Workiat) (Exhaust)

Fig. 221. Illustratinsr the operations which take place in a four-stroke
cycle engine to obtain a power or working stroke.

cylinder and an exhaust valve to let the burnt gases out.

Four-Stroke Cycle. The four strokes in the four-stroke
cycle engine are: (SeeFig. 221.)

First, the suction stroke, during which the piston increases
the volume of the space at the closed end of the cylinder and
thus draws into the cylinder through the inlet valve a charge
of vaporized fuel, and enough air to furnish a sufficient
amount of oxygen to support combustion.

Second, the compression stroke, during which the piston
makes a return stroke and compresses the gases into the clear-

Digitized by

Google

FARM MOTORS Ul

ance space at the end of the cylinder. This operation is
necessary in order to get the full power out of the fuel.

Third, the expansion stroke. Just before the end of the
compression stroke the ignitor acts so that combustion takes
place; and at the end of this stroke there is a high pressure
ready to act under the piston, pushing it forward, thus doing
the work.

Fourth, the exhaust stroke, during which the piston
returns toward the closed end of the cylinder and the exhaust
gases are pushed out through the exhaust valve. At the end
of this stroke the piston is again at the beginning of the suc-
tion stroke. To complete the cycle it is noticed that two
entire revolutions of the crank shaft and fly wheels have been
required and that only one of these four strokes is a working
stroke, or a stroke dimng which the engine is receiving power.
During the other three strokes the fly wheels must furnish the
energy to keep the engine in motion.

Two-Stroke Cycle Engine. The two-stroke cycle engine
is an attempt to increase the niunber of working strokes by
providing an auxiliary chamber in which the gasoline or fuel
mixture is given such an initial compression that at the end
of the exhaust stroke these fresh, imbumed gases imder com-
pression readily displace the burned gases. This displace-
ment takes place so quickly that it is possible to compress the
fresh gases during the return stroke. These operations are
shown in Fig. 222, which shows in outline an engine using the
crank case as a compression chamber. Owing to the larger
niunber of working strokes for a certain rotative speed the
two-cycle engine has the advantage of Ught weight.

As the events in the two-cycle engine occur in every revo-
lution instead of once in two revolutions, the two-cycle engine
is of more simple construction. A secondary shaft operated
by a reducing gear for opening the valves and making one

Digitized by

Google

348 AGRICULTURAL ENGINEERINO

revolution to two of the crank shaft, is not required, and in
many engines the main valves are dispensed with by making
the piston imcover ports or openings in the cylinder walls for
the admission of fresh gases and the escape of those bmned.
This simplicity of construction enables the two-cycle engine

Fig. 222. Illustratinsr the operations wliich take piace in the two-stroke
cycle engine. A, suction into crank case. B, compression in crank
case. C, compression in cylinder combined with A. D, expansion In
cylinder combined with B, (From Farm Machinery and Farm Motors.)

to be built and sold at a lower cost than the four-stroke cycle
engine.

On the other band, the two-cycle engine does not operate
with the same economy in fuel consimiption as the four-stroke
cycle. If the cylinder diameter is large, the mixing of the
fresh and burned gases is so great that there cannot be the
best scavenging or cleaning of the burned gases from the cylin-
der without a loss of unbumed gases to the exhaust. Very
large engines are made on the two-cycle plan by introducing
an auxiliary air-compression cylinder which blows air to clean
out the burnt gases.

The two-cycle engine is a little more difficult to manage,
as a rule, and the carburetor and the ignition system are more
susceptible to slight misadjustments. This is no doubt
largely due to the fact that there cannot be as sharp a suction
upon the carburetor as may be had with the four-cycle engine.

Digitized by

Google

FARM MOTORS 349

This sharp suction is very valuable in assisting to vaporize
the fuel by the rapid rush of air through the carburetor.

QUESTIONS

1. Why is the gasoline or oil engine an important farm motor?

2. To what class of motors does the gasoline or oil engine belong?

3. Why is the gas or oil engine an internal-combustion engine?

4. Why is it correct to speak of the gasoline or oil engine as a gas
engine?

5. Describe the four-stroke cycle tjrpe of engine.

6. Describe the two-stroke cycle type of engine.

7. Compare the advantages of the two-stroke and four-stroke
cycle .engines.

Digitized by

Google

CHAPTER LV
ENGINE OPERATION

Essentials of Operation. Someone has said that there
are four features of the action of the gasoline or oil engine
which must be right or the engine will not run and furnish
power; and if they are right, the engine will run in spite of
everything, assiuning for the time being that the working
parts are in such adjustment as to permit of free move-
ment. These essential features are:

1. Proper mixture of gases.

2. (Compression.

3. Ignition.

4. Correct valve action.

The Gas Mixture. During the suction stroke of the
piston the cyUnder is drawn full of air mixed with a suffi-
cient amoimt of fuel vapor. The amoimt of air and fuel
vapor must be in about the correct proportion or the mixture
will not bmn. For instance, if there be little fuel or if it be
improperly vaporized, the mixture will not be ignited by the
spark produced by the igniter. On the other hand, the mix-
ture will not bum if the proportion of fuel vapor be too large;
oxygen of the air must be present to support combustion.
Pure fuel vapor or gas will not bum, nor will very rich mix-
tures.

Now the range of proportions in which the air and fuel
vapor may be mixed and still give a combustible mixture is
quite limited, and the range of mixtures which will give a
good, strong working stroke is still more limited. The richest
mixture that will bum has been stated by one authority to

350

Digitized by

Google

FARM MOTORS 351

be about one part of gas or fuel vapor to four pai*ts of air.
The same authority gives one part of fuel vapor to fourteen
parts of air as being the leanest mixture that will bum.

It is to be remembered in this connection that of every
one himdred parts of air only 23 parts are oxygen; and it is
the oxygen that supports combustion. The largest constitu-
ent of air, nitrogen, composes about 77 parts of the one
hundred. Nitrogen is entirely inert, and
in the gasoline engine cylinder it occu-
pies space which would be more desir-
ably filled with gasoUne and oxygen.

In changing from a liquid to a vapor,
the fuel is increased in volume some 600
to 1000 times. This means that the
ratio of the volimie of liquid fuel used to
that of air must vary from 1 to 8,000 up tomatic" carburetVr.
to about 1 to 16,000. From this we see ^XZS sup"p,ies'ldS?:
why the carburetor of the gasoline engine auxiliary ^a^r "* vaive
is such a sensitive affair. ^J^^^^t wgh Zl±"

Not only must the ratio of fuel to air be quite constant,
but the difficulties encountered are magnified by the fact that
the mixing must take place between colorless gases and " sight
unseen" inside the engine cylinder. The gas engineer must
resort to tests that will show the condition of the mixture.

If the mixture can be adjusted until it will burn, then the
adjustment for the proper mixture is easy. A too rich mix-
ture is indicated by black smoke from the exhaust; and one
too lean, by a sharp, prolonged exhaust, indicating a slowly
burning mixture. The smoke of a too rich mixture is black,
while that caused by too much lubricating oil is blue.

When the engine is provided with a hit-or-miss governor,
the needle or supply valve should be adjusted to require the
least nimiber of explosions necessary to furnish a given

Digitized by

Google

*a62 AGRICULTURAL ENOINEERING

amount of power and then be slightly closed. The adjust-
ment which gives the least nimiber of explosions does not give
the most economical setting of the needle valve, and that is
why the valve should be closed sUghtly.

Testing the Mixture. The most perplexing trouble
comes when it is impossible to get a single explosion. In this
case certain tqsts must be made to determine whether the
cylinder is flooded with fuel or whether there is not enough
gasoline vapor present to make an explosive mixtm-e. Of
course, tests should be made to determine that the ignition
system is perfect and that an explosive mixtm-e would be
ignited if there should be one in the engine cylinder.

One plan to follow is to shut oflf the fuel supply and clear
the cylinder thoroughly of all gasoline by turning the ei^ne
over several times. This being done, an entirely new attempt
to start the engine will usually meet with success.

A test may be made of the nature of the mixtm'e in the
cylinder by holding a Ughted match to the relief cock as the
engine is turned over. A rich mixture will biun as it comes
in contact with the air; an inflammable mixtm-e will snap back
into the cylinder; and a mixture which is too lean will not
bum at all.

The Compression. It is necessary that a gasoUne engine
compress the mixture of gasoUne vapor and air before ignition
or the full power of the fuel will not be obtained. Failm-e
to s<^ure compression is usually due to leaks, either past the
piston or through the valves.

Leaks. Piston rings are provided to make a gas-tight fit
between the piston and the cylinder. Sometimes these rings
become stuck in their grooves by charred oil and do not
spring out against the cylinder walls as they should. When
this happens, which usually is due to the use of poor lubricat-
ing oil, the rings should be thoroughly cleaned. Where the

Digitized by

Google

FARMMOTORH 353

trouble is not serious, the rings may be loosened by feeding in
kerosene through the lubricator. When the rings become
worn, they should be replaced.

Leaks may^ also take place past the valves. Often
charred oil will lodge on the valve seat, preventing it from

Pig. 224. A sectional view of a gas engine cylinder, showing
the cylinder volume and clearance space.

closing tightly. Cleaning will often overcome this difficulty;
but when scored or pitted, the valve must be ground on its
seat with emery and oil until a perfect fit is again secured.

QUESTIONS

1. What are the four fundamental essentials of gas engine
operation?

2. What is meant by an explosive mixture?

3. What are some of the difficulties encountered in obtaining an
explosive mixture?

4. What are the indications of a rich mixture? A lean mixture?

5. Explain how the quality of the mixture may be tested.

6. How does compression influence the power of an engine?
7* What are the common causes for the loss of compression?

12--

Digitized by

Google

CHAPTER LVI
GASOLINE AND OIL ENGINE OPERATION (Continued)

Ignition. The burning of the fuel in a steam plant is
continuous frojn the time of kindling the fire until the plant is
shut down. In the gasoline engine the fire is quickly extin-
guished, lasting but a part of one stroke of the piston, necessi-
tating the igniting of additional fuel as it is taken into the
cylinder. It is easy to see that if for any reason there is a
failure to ignite the fresh fuel, no power will be obtained from
that particular cylinder. As in the case of failure to secure
the proper mixture and compression, the gas engine vrill not
operate imless each charge is successfully ignited.

Development As indicated, the firing of the charge in
the cylinder is spoken of as the ignition, and the devices that
accomplish it, the ignition system. One of the principal diffi-
culties encountered by the early inventors in developing the
gas engine was that of securing ignition. The early attempts
consisted largely in carrying an open flame into the cylinder
by means of suitable valves. Later, the hot tube was used
generally, and is to some extent at the present time. The
hot-tube igniter consisted of a short length of pipe screwed
into the compression space and kept at red heat by means of
an outside flame. During compression the unbmned gases
pushed the burned gases up into the tube until the fresh fuel
came in contact with the hot surface of the tube, causing
ignition. It is not possible to regulate the time of the ignition
with the hot tube as accurately as desired, and when used with
a small engine, at least, the fuel required to keep the tube hot
is often an important part of the entire cost of operation.

354

Digitized by

Google

FAMM MOTORS

355

These shortcomings on the part of the hot-tube igniter, and
the rapid development of the electric igniter have caused the
general abandonment of the former.

There are two general classes of electric ignition systems
in general use. These systems are generally known as the
"make-and-break" system and the "jump-spark" or high«
tension system. Each of these systems has its advantages.
The make-and-break system is used largely in connection
with stationary engines, while the jiunp-spark is used with
variable-speed motors, like the automobile.

The Make-and-Break System. In the make-and-break
system of electric ignition two electrodes or points are pro-

l0nifor

Sw/fch

Be>.iteryafDry Cella

Fig. 225. Sketch showingr the wiring and essential parts of a make-
and-break system of Ignition. Four standard dry cells form the usual
battery instead of six as shown.

vided in the compression space of the engine cylinder, and are
insulated from each other in such a way that an electric cur-
rent will not flow through them unless they are made to
touch each other. When an electric current is broken, there
is a tendency to produce a spark at the point where the separa-
tion takes place. By placing a spark coil in the circuit the size
of the spark may be much increased. The system consists

Digitized by

Google

S56 AORICULTURAL ENOINEERING

primarily in providing a Bource. of electricity and suitable
mechanism to bring the points together at the proper time
and to separate them at the proper time for the sparks so pro-
duced to fire the mixture in the cylinder.

The make-and-break system does not use high-tension or
high-voltage electricity. Voltage corresponds to pressure,
or ability of the electricity to overcome resistance. For this
reason the make-and-break system does not require such
careful insulation as does the high-tension system. There
are, however, the moving parts inside of the cylinder, and
the mechanism operating it is such that it is not convenient
to make provision for varying the time of ignition. Failm-e
on the part of the make-and-break system may be generally
traced to failure in the source of current, or to a break-down
of insulation. There are many other minor causes of failure,
but space does not permit a discussion of them here.

Testing the Make-and-Break Sjrstem. When an engine
fails to start, a test should be made of the ignition system.
This is generally done by making and break-
ing the circuit by hand outside of the engine
cylinder, and judgment is then passed upon
the size of the spark as to whether or not
it is sufficient to ignite the charge. After
makela n d-break the insulatiou ou the wircs beoomcs worn
and damaged, there may be an escape of
electricity without passing through the igniter points. The
igniter points may become covered with scale, oil, or dirt
which will prevent the electricity from passing from one to
the other when desired. Often the movable points fail to
work freely, owing to lack of oil, preventing the sharp, quick
separation of the points, which is quite necessary to secure a
good, lac spark.

Digitized by

Google

FARM MOTORS

357

The Jump-Spark Sjrstem. The jump-spark system does
not have any working parts inside of the cylinder, where they
are exposed to the high temperature there present. The
mechanism is such that
it is convenient to vary
the time of ignition when
this is used to regulate the
speed of an engine, as it is
in the case of the automo-
bile engine. The jimip-
spark system requires the
use of an induction coil, „„„,„, ^ . ^

' Figr. 227. Sketch showingr the essential
which, when connected to parts of a jump-spark system of igni-

one of the usual sources of

electricity, increases the voltage to such an extent that when
suddenly cut off the new or induced current jiunps a small
gap. The usual spark plug is only a provision for placing
this gap inside of the engine cylinder. Owing to the high
voltage of the jimip-spark system, certain wires must be
very carefully insulated in order that the gap of the spark
plug shall be the path of least resistance for the current

to escape.

Testing. It has been
suggested that tests be
made with the make-and-
break system of ignition
to determine whether or

Fig. 228. A Jump-spark or Induction coll HOt the Systcm is in WOrk-
dissembled to show, construction. j^^ ^^^^^ ^^^^ ^^.^^j^j^ j^

encountered. A convenient way of testing the jump-spark
system is to remove the spark plug and lay it upon the
cylinder and manipulate the circuit-breaking mechanism by
hand. If a good spark be obtained, it may be assimied

Digitized by

Google

358

AGRICULTURAL ENGINEERING

Fig. 229. A
spark plug in
section, show-
ing construc-
tion.

that the trouble lies elsewhere than in the ignition system.
The Batteries. Any fonn of electric ignition requires a
source of electricity. One of the most general forms on the
market is the dry-cell battery. It represents,
perhaps, the cheapest source of electricity, as
far as first cost is concerned. When the cells are
able to furnish a suflScient quantity of electricity,
they are very satisfactory. One of the most
perplexing features of the use of dry-cell bat-
teries is the matter of detennining when the
cells are exhausted, as there is no change in
the outside appearance.
There are instruments, known
as ammeters, which enable
one to determine how much current a dry
cell will furnish ; and where many dry cells
are used, this instrument should always
be on hand to detect exhausted cells. If
an instrmnent is not
available, the strength
of the cells must be
judged from the size
and character of the sparks produced when
tested.

Storage batteries make a very satis-
factory source of electric current for igni-
tion, but provision must be at hand for
^ recharging when they become exhausted.
Fig. 231. An oscii- Magnetos and Dynamos. Perhaps the

lating magneto on ^ •' <. i •

demonstration stand, most Satisfactory source of electnc current
for gasoline engine ignition is the magneto or dynamo,
which is a small instrmnent for making electricity by me-
chanical means. Indications are that it will be only a

Fig.

230. A storage
battery.

Digitized by

Google

FARM MOTORS 359

comparatively short time imtil the magneto will be consid-
ered a necessary part of the equipment of the gas engine.
At the present time the magneto is regarded as almost a
necessity in the operation of the automobile engine. In
selecting a magneto or dynamo, care should be taken to see
that it is well adapted to the service required and that it is
properly installed.

Valve Action. The last of the four essentials for the suc-
cessful operation of the gas engine is proper valve action, or
the correct timing of the valves. It is obvious, after what
has already been written

on this subject, that the
valves must open at the
proper time to let the
gases into the cylinder,
close at the proper time
to withhold them for the
power stroke, and open
again to let the burned
gases escape. The suc-
tion or inlet valve on ^^«' 232. a dynamo called the Auto-

sparker.

farm engines is usually

operated by the suction produced by the piston during the
suction stroke, and, outside of the adjustment of the light
spring which closes the valve, it is self-timing. The exhaust
valve should open before the end of the expansion stroke,
to allow the free escape of the burned gases, and must
close at about the end of the exhaust stroke. The exhaust
valve for an average-sized engine is made to open when
the crank is about 30^ from dead center, but the time will
vary with the speed and size of the engine. Directions
should be found with each engine for the setting of the
valves.

Digitized by

Google

360 AGRICULTURAL ENGINEERING

QUESTIONS

1. Why is ignition so important to the success of a gas engine?

2. Describe the hot-tube igniter.

3. What are the names of the two S3rstems of electric igniticm?

4. Describe the make-and-break system of ignition.

5. Explain how this system may be tested.

6. Describe the jump-spark system of ignition.

7. Explain how this system may be tested.

8. Describe the use of dry cells as a source of current for electric
ignition.

9. How does the djmamo or magneto furnish electricity for igni-
tion purposes?

10. Why is valve action or timing important?

11, Describe in a general way when the inlet and exhaust valves
should open and close with reference to the position of the crank.

Digitized by

Google

CHAPTER LVII
SELECTING A GASOLINE OR OIL ENGINE

The selection of a gasoline or oil engine for the farm is not
easy, owing to the many features of the problem involved.
First, there is the size or horsepower to be decided; second,
the type, involving such features as weight and speed; third,
the moimting; and fourth, the quality of the engine.

The Size. The gasoline or oil engine is used on the farm
for many purposes at the present time, and the power
requirements for these various purposes differ widely. The
following Ust gives the more common uses for the gasoUne
engine and indicates the approximate amoimt of power
required:

Washing machine, 3^ to 1 H.P.

Chum, 1 to }^ H.P.

Pump, J^ to 2 H.P.

Grindstone, J^ to 2 H.P.

Electric generator, 1 H.P. or more.

Feed mill, 3 H.P. or more.

Portable elevator, 3 to 5 H.P.

Com sheller, 2 H.P. or more.

Ensilage cutter, 5 to 25 H.P.

Threshing machine, 6 to 50 H.P.

It is to be noticed that the first four machines require a
rather small engine, while the others either require consider-
ably more power, or they may be operated more advan-
tageously when of a size suitable to a medium-sized engine.
The feed grinder may be obtained in almost any size; but
where magazine bins are not provided and where it is expected

361

Digitized by

Google

362 AGRICULTURAL ENGINEERING

to give the grinder attention while in operation, a large one is
a decided advantage. A grinder using six to twelve horse-
power will grind feed at such a rate that one man will have all
he can do to provide grain for the hopper and to shovel
away or bag the ground feed.

Ensilage cutters, when provided with a pneumatic ele-
vator or blower, require considerable power, and it is an
advantage to have a machine which will take imdivided
bimdles of fodder. To operate such a machine, a 12-horse-
power engine, or larger, is required.

There are small threshing machines on the market which
require Uttle power for their operation, and are no doubt a
success where a small amount of grain is to be threshed. The
small-sized machines, equipped with the modem labor-saving
attachments, such as the self-feeder and the wind stacker,
require about 12 horsepower for their successful operation.
The other larger machines mentioned may be procured in
almost any size to acconmiodate the size of the engine pur-
chased.

From this analysis it would seem that there are two classes
of work on the average-sized farm which require two sizes
of gasoline engines if the work is to be performed economic-
ally. A certain portion of the fuel used by an engine is
needed to overcome the friction within the engine itself, or
to operate it. After enough fuel is furnished to keep the
engine in motion, the additional fuel used is converted into
useful work. The percentage of the total fuel required to
operate the engine proper, when under full load, is not far
from 25 per cent for average conditions. Thus it is seen that
it will require much more fuel to operate a 12-horsepower
engine empty, or imder no load, than to operate a IJ/^horse-
power engine imder full load.

Digitized by

Google

FARM MOTORS 363

The average farm well will not furnish water faster than
it could be pumped with a small IJ^ or two-horsepower
engine; so a larger load cannot be provided by increasing the
size of the piunp or the number of strokes per minute. The
question is often asked, when
the purchase of an engine
for pmnping is contemplated,
whether it would not be best
to purchase a much larger
engine than actually needed
in order that it may be used
for other work. Ifthepufnp-
ing is to be continuous, that
is, every day, it will be foimd
more economical to buy a
small engine to do the pump-
ing and a comparatively
larger one for the other work.
This will be explained by
the following calculation:

Fuel per year for IJ^horse-
power engine, light pumping load,
2 hours per day, equals 0.2 gal-
lons times 365, or 73 gallons.

Fuel per year for 8-horse-
power engine, light pumping load,
2 hours per day, equals 0.45 gal-
lons times 365, or 164.3 gallons.

Difference equals 164.3 73, Fig. 233. a special type of engine

or 91.3 gallons. "^^** '°'' pumping.

At 15c per gallon, 91.3 times 15c equals $13.69.

This will more than pay for the interest on the cost of the
smaller engine, and its depreciation. If the comparison be

Digitized by

Google

364 AGRICULTURAL ENGINEERING

made with a larger engine, the difference in the cost of oper-
ation would be greater.

The Type of Engine. The type of engme to select will
depend largely on the kind of service required. If the engine
is to be placed upon some horse-propelled machine, like the
binder, to drive the machinery, a light-weight engine is
highly desirable. Lightest weight may be secured by select-
ing a high-speed two-stroke cycle engine. The four-stroke

Fig. 234. A gasoline engine used to operate the machinery of a grain

binder.

cycle may be made quite light by introducing high rotative
speed and using refinement in construction. Usually, high
speed is conducive to increased wear and short life. Modem
automobile design has, by improved methods and materials
of construction, practically overcome the objections to the
high-speed engine.

Digitized by

Google

FARM MOTORS 365

The average farm machine does not require an extremely
steady power, and for this reason the hit-or-miss governed
engine is the most satisfactory for average conditions, on
accomit of its simplicity and economy. Where an ei^ne is
used for electric lighting, the throttle-governed engine or an
engine with extra-heavy fly wheels should be used.

The Mounting. The stationary engine has many advan-
tages over the portable engine in that it can be better pro-
tected and, when mounted upon a good foimdation, can per-
form its work under the best conditions satisfactorily. The
pmnping engine should be a stationary engine; it may also
perform such other work as may be brought to it. It will
prove highly satisfactory to locate the pump house, the farm
shop, and the milk house so as to enable the power from one
engine to be used in all.

The Quality. A poorly constructed and inadequately
equipped engine is a bad investment at any cost. A gasoline
engine should not only run and furnish power for a time, but
it should be so constructed and of such material as to have a
long Uf e and require the minimum amoimt of attention and
repair. In considering the purchase of an engine, cognizance
should be given to the chief factor which causes the manu-
facturer to build a high-grade engine, — ^namely, the desire to
earn a reputation for building first-class goods.

The vital parts of a gasoline engine, as of any machine,
are those which wear and which must be adjusted and
repaired. The following points are important: First, these
parts should be provided with adequate lubrication, as it is
the principal factor in reducing wear. Second, the size of the
parts that wear should be of Uberal dimensions and of a good
quahty of material!. Third, the parts should be easily
adjusted. Fourth, the parts should be easily replaced when
worn out.

Digitized by

Google

866 AGRICULTURAL ENGINEERING

Testing. A brake test may be made of the engine to
determine the amomit of power it will deliver and the amount
of fuel required per horsepower per hour. In addition to

Flff. 235. A gasoline engine arranged for a test. The brake Is on the

back side.

determining the power of the engine, if the test be continued
for a time (two hours or longer) an examination may
be made of the efficiency of the cooUng system and of the

Digitized by

Google

FARM MOTORS 367

ability of the engine to carry a full load without any over-
heating of the bearings, or other disorders.

Estimating Horsepower. The horsepower of a gasoline
engine may be estimated from the diameter of the cyUnder,
the length of stroke, and the revolutions per minute. If these
quantities are known for several engines, a comparison of their
horsepower may be made. Such an estimate can only be
considered approximate, however.

A satisfactory formula for estimating the horsepower of
gasoUne engines of the four-stroke cycle type is as follows:

D» L R*
B.H.P. =

18,000
where D = diameter of cylinder in inches.
L — length of stroke in inches.
R = revolutions per minute.

For two-stroke cycle enghies the formula should read as
follows:

D»LR

B.H.P.=

13,600

Another formula which has been suggested for vertical

tractor engines is:

66 D» L Rt
B.H.P. =

1,000,000
For horizontal engines the formula is made to read as
follows:

75 D» L R

B.H.P. =

1,000,000

These formulas will agree very closely with the brake
horsepower of tractor engines developed in public test.

♦E. W. Roberta.
fW. F. MaoOregor.

Digitized by

Google

368 AGRICULTURAL ENGINEERING

In sheeting an eng^ie, the accessories are often gLvea little
attention, when they should be carefully inspected; and, if
the engine is not well Equipped in the way of first-class acces-
sories, they should be selected.

The lubricating system should be permanently installed
and so arranged as to give all working parts a liberal supply of
oil. The multiple oil pump is to be highly conunended in
this connection. ExpcKsed oil holes, which may become filled
with dirt and grit, should be guarded against.

Summary. The following outline is suggested to aid a
purchaser in making a comparison of the merits and value of
different engines. The information asked for in tiiis outline
should be so obtained from all the engines considered.

Things to Consider in Selecting an Engine.

Name of engine.

Type — stationary or portable.

Rated horsepower.

Diameter of cylinder.

Length of stroke.

Revolutions per minute.

Piston speed per minute.

Calculated horsepower by formula.

Cooling system.

Frame — construction.

Main bearings — construction, accessibility, and adjustment.

Cylinder and piston — construction.

Crank — construction.

Gears — construction.

Valves — construction and accessibility.

Ignition system — construction and protection.

Lubrication system — construction and completeness.

QUESTIONS

1. What are the principal features to be considered in selecting
a gasoline or oil engine?

Digitized by

Google

FARM M0T0R8 369

2. What will determine the size to be selected?

3. Why is it not economy to use a large engine for light work?

4. How much power is usually required to operate a farm pump?
A chum? A washing machine? A feed mill? A com sheller? An
ensilage cutter? A threshing machine?

5. What should govern the tjrpe of engine to be selected?

6. Where may a portable engine be used to advantage?

7. What are some of the indications of quality in a gasoline or oil
engine?

8. Of what use would a test of the horsepower be?

9. Explain how the horsepower of an engine can be estimated.

10. A four-strdke cycle engine has a cylinder 8 inches in diameter;
the stroke is 10 inches long and it operates at 360 revolutions per min-
ute. Estimate its horsepower.

11. What are some features to consider in selecting the accessories
of an engine?

12. Give a list of the parts that should be inspected in selecting a
gasoline or oil engine.

Note : — ^The instructor here should furnish the students with problems
in the estimating of the horsepower of engines, perhaps measuring
certain engines and comparing the estimated horsepower with manu-
facturer's rating.

Digitized by

Google

CHAPTER LVIII
THE GAS TRACTOR

The Utility of the Gas Tractor. The gas tractor — ^and
reference is here made to the tractor with the internal-com-
bustion engine — ^has developed faster during the past ten
years than has any other machine used on the farm. On the
broad prairies, where the conditions are the most favorable
for its use, it is rapidly taking first place over the horse; and in
less favorable localities, where intertilled crops are grown,
the gas tractor is being successfully tried out. All this has

Fig. 236. A femall gas tractor plowing. It may be successfully
operated by one man.

taken place despite the fact that ten years ago the gas tractor
was an unusual sight. No one reason can be given for this
increase in power farming. The new broad open fields of the
West, the rapid development of the internal-combustion

3T0

Digitized by

Google

FARM MOTORS 371

engine, and especially the factor of economy, are suggestive
causes.

The tractor has been regarded as unwieldy in small fields,
but this difficulty has been largely overcome by using the
proper system in laying out the lands. One convenient sys-
tem is to lay out the fields in lands of such widths as to lose
little time in turning at the ends. A strip is left at each side
of the field of a width equal to the turning strip at the ends,
and sides and ends are turned last by plowing around the
entire field.

The tractor was first introduced for plowing, as this
requires more power than any other kind of farm work; but it
is also now being generally used in seeding and harvesting.
In many instances several
of these operations are
carried on at the same
time.

A gas tractor consists
of an engine, the transmis-
sion, and the truck. These
parts will now be discussed
under separate heads.

The Engine. The trac-
tor engine does not differ
materially from any other ^ig. 237. The motor^of an oii-buming

internal -combustion en-
gine. No one type of engine has been generally adopted
for traction purposes. However, nearly all are of the four-
stroke cycle type. The differences in these motors lie in the
number of cyUnders, the speed of the engine, and the method
of governing.

The single-cylinder engine has a decided advantage in
simplicity. It is easier to manage a one-cylinder than a two-

Digitized by

Google

372 AGRICULTURAL ENGINEERING

cylinder engine. If the engine is not in proper adjustment
there is no tendency to continue to operate it, as there is when
there are two or more cyUnders, letting the remaining ones
furnish more than their share of the power. A multi-
plicity of cylinders, on the other hand, for a given power,
reduces the magnitude of the impulses and thus to a large
extent relieves the gearing of severe shocks. The multiple-
cylinder engine furnishes a steady power and is a little more
agreeable to operate for that reason. There seems to be
little doubt but that greater skill is required to keep the com-
plicated engine in proper adjustment and
repair.

The Clutch. As the gas engine cannot
be started under load, it is necessary to
have a clutch to engage the engine with
gears or with chains and sprockets that
transmit the power to the drivers. This

Pig. 238. One form i . i . n i . n

of clutch. The wood- clutch IS generally used to engage a pulley

en shoes are forced t_ j.t_ • • j x j • x x*

outward against the When the cngmc IS used to onve a station-
elISag?pg u^by^frfcl ary machiuc with a belt, when the traction
"^"- gearing is disengaged.

In construction, the clutch consists of shoes usually made
of wooden blocks, which, by suitable levers, are made to bear
against a disk or other surface with sufficient pressure to
cause the power to be transmitted through the parts in
contact. The form and material of the friction surfaces
vary widely. Sometimes the clutch takes the form of two
cones, hence the name cone clutch. Again, the friction
may take place between a series of disks, one-half of which are
attached to the engine shaft and the other half to the trans-
mission. This type of clutch is called a multiple-disk clutch,
and the disks are usually engaged by the pressure of a spring
which may be brought to bear at the most suitable time.

Digitized by

Google

FARM MOTORS 373

The clutch is a vital part of the tractor and should be
located as close to the engine as possible. The higher the
speed at which the clutch rotates the smaller force it will have
to transmit.

The Gearing. The gears are an important part of the
tractor. They should (1) be of liberal dimensions and of
great strength; (2) be constructed of such materials as to
resist wear to the greatest advantage ; (3) be adequately lubri-
cated and protected from dirt and grit.

Change of Speed. Change of speed is especially desirable
with light tractors and is quite necessary where the land is
rolling. The load which any tractor will draw is limited by
the load it is able to draw up the steepest incUne. If a
reduction of speed be made for inclines or hills a larger load
may be carried continuously.

A reverse in direction of travel or a change of speed is
accomplished in two general ways: by sliding gears, which is
the accepted method now used in automobiles; and by plane-
tary gears. The former is the simpler method but is not so
convenient of operation.
Planetary gears take
their name from the
gears, being fitted to a re-
volving frame or spider.

The Trucks. One of

,1 , . ,j. 4. «4. P*S- 239. Th^ truck for a gas tractor.

tne most important parts showing frame, gearing, and steering and

of the modem tractor is ^^*"*"^ "^^^'^•
the truck, which consists of the frame and the steering and
drive wheels. The frame is the backbone of the tractor,
and to it are attached the bearings that carry the main axle
and the shafts which support the gears.

The Steering Wheels. Two methods of constructing the
axle of the steering wheels are in common use. In one the

Digitized by

Google

374 AGRICULTURAL ENGINEERING

axle is pivoted at the center, and steering is accomplished by
revolving the axle about this pivot or king bolt. The main
advantage of this system is that the steering wheels may be
turned while the tractor stands still.

In the other style the axle is pivoted just inside of each
steering wheel and each wheel is turned about its own pivot.
This style of steering mechanism is easy to handle while in
motion. It is quite positive, that is, there is no slack to take
up in the cludns, and it is of more rapid action than the other
style.

The Traction Wheels. The traction wheels should be
carefully considered in making a selection of a tractor, because
certain wheels are adapted to certain conditions. If the
groimd over which the tractor must pass be soft, it is highly
desirable that both the drive and the steering wheels be as
high as practical. Wheels of large diameter present a larger
section of their periphery to the surface of the groimd, and
so cut in but slightly. Extensions are provided by all manu-
facturers for making the drive wheels wider for work in
soft groimd. Where the soil is exceedingly soft, the cater-
pillar tread or creeping grip should be used. It is possible to
use this type of tractor in marsh or swamp soils or over sand
where it is impractical to use horses.

The Equipment. Too much emphasis cannot be laid upon
the importance of securing a tractor which is well equipped.
Often there is a serious loss of time resulting from the poor
quality of parts that cost but a few cents. A purchaser
should see that the tractor has modem high-class ignition,
carburation, and lubrication systems.

QUESTIONS

1. What are some of the conditions under which the gas tractor
can be used with economy?

Digitized by

Google

FARM MOTORS 375

2. To what kinds of work is the present gas tractor adapted?

3. What are some of the advantages and disadvantages of the
multiple-cylinder engine for a tractor?

4. Why is the clutch an important part of the gas tractor?

5. Describe the differences in the shoe, cone, and multiple-disk
clutches.

6. Why is the gearing an important part of a gas tractor?

7. How may a change of speed be accomplished?

8. What is the purpose of the frame?

9. Describe two styles of steering wheels.

10. Discuss the construction of traction wheels.

11. Why should the equipment of the tractor be given careful con-
sideration?

Digitized byVjOOQlC

CHAPTER LIX
THE STEAM BOEDER

The Steam Power Plant. A steam power plant consists
essentially of two parts, the steam boiler, for generating steam
by the combustion of fuel; and the steam engine, which con-
verts into work the energy contained in the steam. It is
customary, however, to refer to the entire steam plant as the
steam engine, when the plant is small. When the boiler and
engine are moimted on wheels and arranged with suitable
gearing for propelUng itself as well as for drawing loads, the
outfit is referred to as a traction engine. Of late years it
has become customary to refer to the steam traction engine as
the steam tractor. The subject of the steam power plant will
be divided into three parts, confined to as many chapters, as
follows: the steam boiler, the steam engine, and the steam
tractor. At one time the steam engine as defined above and
the steam tractor were the principal sources of power for
agricultural purposes, when large units were required. The
development of the internal-combustion engine and tractor
has been more rapid in recent years than that of the steam
engine and tractor.

The Principle of the Steam Engine. The steam engine is
a heat engine, in that its function is to transfer the heat pro-
duced by the combustion of fuel, usually wood or coal, into
mechanical energy. It might be styled an external-combus-
tion engine, in that combustion takes place outside of the
boiler proper and the heat is absorbed by passing the hot
gases through tubes surrounded by water.

370

Digitized by

Google

FARM MOTORS 377

In an open vessel water cannot be heated above the boil-
ing point of 212° F., but heat continues to be absorbed and is
used in the formation of vapor. Water under pressure boils
at a higher temperature. Thus if the pressure inside the con-
taining vessel were two poimds greater than atmospheric
pressure, the boiling point would be about 228*^ F. Changing
water into vapor increases its volume many fold. At atmos-
pheric pressure the volume of the vapor is about 1700 times
that of the 'liquid. At 100 poimds pressure the volume of
the steam is about 240 times the volume of the Uquid. Water
vapor, or steam, is a colorless gas which obeys all of the laws
of gases as far as expansion and change of temperature are
concerned.

Functions of a Boiler. The fimctions of a boiler are to
absorb heat from the hot gases produced by the burning of
fuel and to transmit it to the water contained within, causing
it to vaporize into steam. The steam boilers used in agricul-
tural plants and in traction engine service include the firebox,
or furnace, which may be placed either directly underneath
the main part of the boiler or entirely within it.

Location of the Furnace. Boilers with the fire box out-
side of the boiler proper are called externally-fired boilers.
This type can safely be used for stationary work and are
usually set in brick work, which forms a large part of the
furnace. Those which have the furnace within the main
body of the boiler, or shell, as it is called, are said to be inter-
nally-fired boilers. Most of the boilers used in agricultural
practice and all of the boilers used for traction engine service
are internally fired.

The Vertical Boiler. The vertical boiler is used in small
imits and where space is especially valuable. It consists of
a cylindrical shell containing a furnace in the lower end, over
which is placed a tube sheet or plate and a system of tubes.

Digitized by

Google

378 AGRICULTURAL ENGINEERING

These boilers are not regarded as very durable and are quite
diflScult to clean properly.

The Locomotive Type of Boiler. The locomotive type of
boiler is the one most generally used for trac-
tion engine service. It consists of a fire box
made of steel plates, in which the furnace is
placed; a cylindrical shell extending forward,
containing a comparatively large number of
tubes; a smoke box at the front end; and a
stack to carry the smoke away.

The fire box is almost entirely surround-
. ed with water. The plate directly above the

Pig. 240. A . x^ f

vertical boiler, fire is Called the crovm sheet and the plates
valve; B. try forming the sides of the box are called side

cocks; C, Injec- » . ▼ • x n -i

tor: D. hand shects. In some mstances fire boxes are so
gauge; >r«"au«e made as to have water beneath the grates;
doorf'H. 'ash such a boilcr is said to have a water bottom.
^^^' The boiler has a cylindrical chamber riveted

to the top of the shell, in which the steam collects and from
which it is drawn to the engine. This part is called the
steam dome, and is a device for drying the steam.

All parts of the boiler are made of the best steel plates, and
the seams are carefully riveted together. The joints are made

Fig. £41. A boiler of the locomotive type in section: /f, steam dome;
B, smoke box; C, fire box; D, grates; E, tubes; F, crown sheet.

Digitized by

Google

FARM MOTORS 379

tight by calking or battering the edges of the seams down
with a special tool designed for the purpose. The flat plates of
the fire box are supported by bolts or studs running from one
plate to the other. These are called stay bolts, except those
over the crown sheet, which are called crown bolts. The
boiler is usually provided with a valve at the lowest point,
which may be opened to allow any sediment in the boiler to
be blown out.

In the management of the locomotive type of boiler, great
care should be taken to keep the water over the crown sheet
at all times.

Return-Flue Boilers. The return-flue boiler has a large
cyhndrical shell in which a comparatively large flue is placed,
large enough to contain
the furnace. The heated
gases pass to the front end
and then back through j
tubes to the smoke box in
the back end. One ob-
jection to this type of boiler
is the Umited amount of 1

Crat-e surface which can ^Ig. 242. a sectional view of a retum-
1 flue boiler.

be provided. This type,

however, is regarded as one of the safest, and is very eco-
nomical in the consumption of fuel.

Capacity of Boilers. The capacity of a boiler is usually
designated in horsepower. Formerly this meant the capacity
to supply enough steam for an engine of the designated
horsepower. Now boiler horsepower means the capacity
to absorb a certain amount of heat in a given time. The
standard horsepower as established in this country is the
capacity to evaporate 30 lbs. of water per hour into steam at

Digitized by

Google

380 AGRICULTURAL ENGINEERING

70 lbs. pressure by the gauge from the feed water at a temper-
ature of 100° F.

It is easy to see, however, that the capacity of any boiler
depends on its ability to bum fuel, or the area of the grate
surface, and on the heating surface which will absorb the heat
produced. Thus it is possible to estimate the capacity of the
steam boiler from the size of the grates, allowing from 3^ to ^
square foot for each horsepower. In like manner the horse-
power may be calculated by determining the entire heating
surface of the boiler, or the area of the plates and tubes which
have heated gases on one side and water on the other, and
allowing 14 squarefeet of heating surface for each horsepower.

Quality of Steam. As steam leaves the boiler there is a
tendency for it to carry water with it in the form of spray.
It is the purpose of the steam dome to cause the water to
settle from the steam as fast as possible. Steam which con-
tains water in the form of spray is called wet steam, and the
proportion of water to steam is sometimes called the quality
of steam. Steam which does not contain any water is said
to be dry steam. When dry steam is passed through highly
heated tubes it is heated above the boiling point of water for
the pressure under which the steam is confined. When in
this condition the steam is said to be superheated. Some
boilers are provided with superheaters for raising the tem-
perature of the steam in this way. To prevent the loss of
heat it is customary to cover the pipes leading the steam from
the boiler to the engine with some non-conductive material in
the shape of pipe covering.

Boiler Accessories. All boilers must be provided with
certain accessories, in order to permit of their successful
operation and management.

Gauge Cocks. Boilers are usually provided with two or
three gauge cocks to enable the fireman to determine the

Digitized by

Google

FARM MOTORS 881

height of the water within the boiler. If the gauge cock
below the surface of the water be opened, a cloud of white
vapor will be emitted; if the cock in connection with the steam
space be opened, a colorless gas will escape. In this way
the height of the Uquid may be determined at any time. It
is customary to put the lower gauge cock sUghtly above the
level of the crown sheet or upper tubes.

The Gauge Glass. In addition to the gauge cocks, the
gauge glass is provided, which shows directly the height of
the water in the boiler. Care should be taken to see that the
gauge glass does not become clogged with sediment and thus
fail in accuracy. The low water condition is reached when
the water does not cover the heated plates of the boiler.
Steam is not a good conductor of heat; so if the plates become
uncovered they are quite sure to become so hot as to be
softened and perhaps destroyed by the pressure of the steam.
Low water is one of the common causes of boiler explosions.

The Pressure Gauge. Another essential accessory for the
steam boiler is the pressure gauge. This instrument indicates
the pressure of the steam within the boiler in poimds per
square inch. The usual pressure gauge consists of a hollow
brass tube curved to a circle, which tends to straighten as the
pressure within increases. By connecting this tube with a
needle over a graduated dial, by suitable mechanism, the
pressure may be indicated directly. A siphon directly below
the gauge prevents steam from entering and heating the tube
and changing its elasticity.

The Safety Valve. Every boiler should be provided with
a safety valve, which will permit the escape of the steam as
fast as generated, after a certain pressure has been reached,
in order that the pressure shall not exceed the strength of the
boiler. The usual safety valve is held closed by a spring
which may be adjusted for the desired pressure. Care should

Digitized by

Google

8S2 AGRICULTURAL ENGINEERING

be taken to see that the pressure valve is kept m workmg
order, and that it is not set too high for the strength of the
boiler. It should also have sufficient capacity to release the
steam as fast as it can be produced in
the boiler under any condition.

The Fusible Plug. As an additional
safety device, a fusible plug, containing
a core made of some metal with a low
melting point, Uke tin, is placed at the
vig. 248. A spring- highest poiut of the crown sheet which
loaded safety va ve. ^^ ^^ ^^^ exposed by low Water. When,

because of low water, the plate becomes heated, the soft
metal core of the plug melts away, causing the steam to blow
on the fire and put it out.

The Boiler Feeder. In order to re-
ceive additional water the boiler must be
provided with some sort of feeder. One
such device is the crosshead pump, which piugr, which is placed
is attached directly to the crosshead of shown ""It^F ^n*^Fi"
the engine and can be operated only when ^*^'
the engine is rimning. The independent pump has a steam
cylinder of its own and may be operated by steam from the
boiler. This type of pump is practically a small steam engine.

Another form of boiler feeder is
the injector, which takes steam
from the boiler and, by allowing
it to expand, converts its energy
I into kinetic energy. As this steam
strikes a supply of cold water
within the injector it condenses.
Fig. 245. A standard type of but the impact drfves the water

into the boiler.
The Feed Water Heater. Many boilers are provided witti
feed water heaters which use the exhaust steam from the engine

Digitized by

Google

FARM MOTORS 38^

to heat the water as it is forced into the boiler. The heat
thus saved may amount to as much as ten to fifteen per cent.
Boiler Management. In managing the boiler care should
be taken to see that the flues are kept free of soot, in order
that the heated gases may come in direct contact with the
metal, and that the boiler is kept clear of incrustation on
the inside. Such accumulations do not have the heat-con-
ducting properties of the steel and result in a serious loss of
heat. If the scaly deposits from the water become too thick,
the heat may not be carried away from the plate fast enough
to prevent it from becoming overheated. Thus care should
be taken not only to use water which is free from foreign sub-
stances, but also to clean the boiler frequently.

exhaust steam.

Foaming sometimes occurs in a boiler, due largely to the
presence of dirt, alkah, grease, or other foreign matter. It
causes a large amoimt of water to be carried away with the
steam, and prevents the engineer from determining accu-
rately the true level of the water. Great care should be taken
in managing the boiler when foaming takes place.

Low water in a boiler should always be guarded against;
and if at any time it should occur, the further generation of
heat should be stopped and the boiler allowed to cool. It is
inadvisable to try to remove the fire, as it is quite sure to
increase its intensity. The best procedure is to cover tlie

Digitized by

Google

384 AGRICULTURAL ENGINEERING

fire with ashes, earth, or even green coal. Do not try to feed
more water into the boiler, as cold water is quite apt to crack
the hot plates and the great amount of steam su^ldenly gen-
erated may cause an explosion. The steam boiler imder
pressure contains a large amoimt of energy, and a boiler
explosion is very disastrous.

QUESTIONS

1. What are the essential parts of a steam power-producing plant?

2. Explain how heat is converted into power by the steam plant.

3. What is the function of the steam boiler?

4. What two general locations may be given to a furnace?

5. Describe the vertical boiler and the conditions to which it is
adapted.

6. Describe the construction of the locomotive type of boiler.

7. What is meant by a return-flue boiler?

8. How is the capacity of a boiler designated?

9. How may the horsepower of a boiler be estimated?

10. What is meant by "quality of steam"?

11. What is the use of gauge cocks and the gauge glass?

12. What is the purpose of the pressure gauge?

13. What is necessary to provide a boiler with a safety valve?

14. Describe the use of the fusible plug.

15. What is the purpose of the boiler feeder?

16. What is the use of the feed water-heater?

17. Describe in a general way the management of a steam boiler.

18. What is meant by "foaming"?

19. What should be done in case of "low water"?

Digitized by

Google

CHAPTER LX .
THE STEAM ENGINE

Mounting. Steam engines used in agricultural work are
usually mounted directly upon the boiler, making with the
boiler a complete power plant, as in the case of a portable or
traction engine. An engine moimted upon a masonry foim-
dation is said to be a stationary engine. All such engines do
not differ essentially in construction.

Principle. The steam engine consists fundamentally of
a cylinder containing a close-fitting piston. This piston is
connected through a piston rod to a crosshead and in turn
through a connecting rod to a crank on the engine shaft. The
crosshead is operated between guides. The steam is admit-
ted at the ends of the cyUnder through valves contained
within the steam chest. The proper
action is given to the valves by an
eccentric on the engine shaft, con-
nected either to the valve rod, which
extends into the steam chest in the
case of a nonreversing engine, or to
the reversing mechanism on a revers-
ing engine. As steam enters the ^,^ ,,, ^ 3^^,,,^^, ^,,^
cyUnder it pushes on the piston and SL^'or'^^Bimpi" englnr""
causes it to move. After the piston

has completed a part of the stroke, the valve closes, but the
expanding pressure of the steam in the cyUnder enables it to
perform additional work on the piston. At the end of the
stroke the steam is released, and the pressure is applied to the
opposite side of the piston. This is all done automatically

13— 385

Digitized by

Google

?M AGRICULTURAL ENGINEERING

by the vaJve mechanism, or valve gear, as it is called. The
piston is fitted with rings which expand against the walls of
the cylinder, making a gas-tight fit. The power developed
by the engine is proportional to the travel of the piston in one
minute and the average pressure of the steam on its face.

Compound Engines. The compound engine has two
cylinders. The steam is admitted first into the smaller one
and allowed to expand to a certain pressure, and then it passes
to the second, where it expands more fully. The compound
engine enables the cyhnders to be maintained at more nearly

Fig. 248. A sectional view of the cylinders and steam chest of
a compound engine.

the temperature of the steam. As steam expands, it cools;
and when fresh steam is admitted after the expansion of a
cylinderful, some of it condenses, losing part of its power.
Gompoimd engines also tend to equalize the pressure of the
steam on the piston throughout the stroke, giving a steadier
motion and lowering the stress upon the working parts.

The Double Engine. Many traction engines are pro-
vided with two cylinders, making a double engine. The
cranks are on the same shaft, but are located at an angle of
90 degrees with each other, so that at no time can both cranks

Digitized by

Google

FARM MOTORS 387

stop in line with the connecting rod, or be on dead center, in
such a way that the engine cannot be started by the appHca-
tion of steam.

The two-cyUnder engines give a steadier motion but are not
usually as economical in the use of steam as the single-
cylinder engines, and are more expensive.

The Fly Wheel. All steam engines and especially single-
cylinder engines must be provided with a fly wheel to carry
the engine over dead center, when the steam cannot act effec-
tively upon the piston. It is customary to make this fly
wheel in the form of a pulley, from which the belt
may be rim to other machines as desired.

The Governor. The purpose of the governor is
to maintain a uniform speed. The usual construc-
tion of a governor is similar to that shown in the
accompanying illustration. The fly balls are
thrown outward by centrifugal force as they are
rotated, thus gradually closing the valve through
which the steam must pass. Governors may be
adjusted for different speeds. . Fig. 249.

* r\ • i> ^ common

Lubrication. One important fea- typeofgov-

. iT , ernor.

ture of the operation of the steam
engine is the lubrication of the piston, which
is usually accomplished by admitting oil with
the steam. The two devices in common use
for feeding the oil uniformly are the oil pump
and the lubricator. The oil pump is driven
by the engine and is simply a small pump
sight- feed iubri- connectcd with a suitable reservoir for the oil.
It can be adjusted to feed oil at any specified
rate. The best kinds have a sight-feed device, which en-
ables the engineer to see the rate at which the pump is feed-
ing the oil.

Digitized by

Google

388 AORICULTURAL ENGINEERING

The lubricator consists of a tank of oil connected under-
neath with a short column of water. The excess weight of
water over that of the steam when applied at the bottom of
the oil reservoir enables the oil to be fed through a small
valve, a drop at a time. The accompanying illustration
shows the construction of a lubricator.

QUESTIONS

1. How is the fann steam engine usually mounted?

2. Explain the principle of the steam engine.

3. Describe the compound engine, and what advantage does it
offer?

4. What are the merits of a double engine?

5. Why is it necessary for a steam engine to have a fly wheel?

6. Describe the action of the governor.

7. Describe the action of the steam engine lubricator.

8. What other oiling device is in common use?

Digitized by

Google

CHAPTER LXI
THE STEAM TRACTOR

A steam boiler and engine mounted upon skids or on a
truck to permit them to be moved from place to place make
what is called a portable steam engine. If an engine be pro-
vided with means of ready control and with gearing for trans-
mitting the power to the traction wheels, thus enabUng it to
propel itself forward over the ground and perhaps pull a load
after it, the outfit is called a steam traction engine, or a steam
tractor. The latter term has come into use recently.

The steam boiler and the steam engine have been dis-
cussed under separate heads. This chapter will be devoted
to a discussion of the features of the steam tractor other than
the boiler and the engine.

The Mounting of the Boiler. There are two general types
of mounting for the steam tractor boiler. One has a frame
connecting the traction and steering wheels in such a manner
as to form a truck sufficiently strong to support the boiler.
As now generally manufactured this is called the under-
mounted tractor, but a general name for this style of construc-
tion 18 frame mounted.

Again, the boiler may be used as the frame for the engine
and the truck, in which case the gearing is attached to the
boiler by brackets or flanges riveted to the boiler. This
construction, called top mourUing, is in more general use, but
is criticised by some because the boiler is subject to the
stresses produced in transmitting the power from the engine
to the traction wheels. When the traction wheels are

Digitized by

Google

390 AGRICULTURAL ENGINEERING

mounted on brackets attached to the side of the boiler, the
boiler is said to be side-mounted.

When an axle'is provided for the traction wheels and it is
placed to the rear of the boiler, it is said to be rear-mounted.
As it is quite impossible to keep the traction wheels in the
side-mounted engine perfectly true, the rear-mounted form
is generally recognized as being the more preferable of the two.
Any wear or spring at the outer ends of the axles will allow the

Fig. 251. An undermounted double-cylinder steam tractor.

wheels to approach each other at the top and to spread at the
bottom, thus throwing the gearing out of alignment.

Some rear-moimted boilers have the main axle mounted
with radius arms, that the boiler may be carried on springs
and still permit the gearing to be in proper mesh at all times.

The Mounting of the Engine. The usual method of
moimting the engine is to attach it to brackets or flanges
riveted to the top of the boiler proper. This construction is
generally referred to as top mounting.

As previously mentioned, another type of construction
provides a frame suflBiciently strong to carry the boiler and

Digitized by

Google

FARM MOTORS 391

engine. In this case the engine is placed underneath the
boiler, and is styled under^mounted. This construction
relieves the boiler of all stress due to the transmission of
power and places the engine where it may be attended by
the engineer standing on the groimd.

The Steering Wheels. The steering wheels of the steam
tractor engine are generally mounted on an axle which
may be turned by means of a hand wheel and a worm gear.

Fig. 252. A top-mounted steam tractor.

By turning the hand wheel a chain attached to one end of the
axle is shortened, while another at the other end is lengthened.
In large engines the power for steering is often supplied by a
separate engine or is derived from the main engine by
friction clutches.

The Traction Wheels. The traction wheels of a steam
tractor are important features o'f the outfit when the tractor
is to be used for drawing loads or machines. The supporting
power of the wheels depends upon the diameter of the wheel

Digitized by

Google

992 AGRICULTURAL ENGINEERING

and the width of the tire. On soft ground, it is customary to
provide an extra width of tire in the form of extensians, which
may be removed when not needed.

In order to grip the surface of the soil sufficiently, the
traction wheels must be provided with cleats, lugs, grouters,
or spikes, which grip the soil and enable the tractor to exert a
greater tractive force. The form of these lugs should be
adapted to the conditions under which they work.

Rating. The size or capacity of the steam tractor is
designated in horsepower. Formerly it was customary to
indicate its tractive power in terms of horses. This rating
has since become known as nominal rating, and is bdng
superseded largely by the brake horsepower rating, which
indicates the most practical power output of the engine
proper. This rating is ordinarily about three times the
nominal rating.

A large part of the power of the engine is used in propelling
the tractor and in overcoming the friction of the gearing.
The tractive efficiency of a tractor is the ratio between the
power deUvered at the draw bar and the power furnished by
the engine. Ordinarily this is about 50 per cent, but on soft
ground it may nm as low as 35 or 40 per cent. On hard roads
it may be much higher than 50 per cent.

Control. The control of the steam tractor is placed (1) in
a throttle, through which the admission of steam to the
engine is controlled; (2) in the reverse, which controls the
direction of rotation of the engine; and (3) in a clutch similar
to that described for gas tractors which connects the engine
to the transmission. Some steam tractors have a brake by
which the tractor may be held in place.

The Clutch. The clutch on a steam tractor universally
operates within the fly wheel of the engine. The friction

Digitized by

Google

FARM MOTORS 393

shoes used are made of wood, and are forced out against the
rim of the fly wheel by suitable linkage.

The Differential. In order to permit the tractor to turn
oomerS; or change direction a mechanism must be introduced
which will allow one traction wheel to travel faster than the
other. This mechanism is called the differential. There are
two types of differentials, the bevel gear and the planetary.

The Gearing. The gearing of a steam tractor is an
important part of the outfit, especially when the tractor is
used for traction purposes. It is now customary to make
the gears very ample in size and of material which will resist
wear to the greatest extent and still be capable of resisting
the shockswhich mustnecessarily comeupon them. Further-
more, the tractor should be provided with means of excluding
dust and grit from the gears, and with a system of lubrication
that will at all times keep the gears amply lubricated.

QUESTIONS

1. Discuss the different types of boiler mounting.

2. Explain two ways of mounting the engine.

3. In what two ways may large tractors be steered by power?

4. What are some of the important features in the construction of
the traction wheels?

5. What is the purpose of the cleats on the drive wheels?

6. How is the power capacity of a steam tractor designated?

7. How is a steam tractor controlled?

8. What is the purpose of the differential gearing?

9. Why is the gearing of a steam tractor worthy of careful atten-
tion?

LIST OF REFERENCES

Instructions for Traction and Stationary Engineers, William Boss.
Farm Engines and How to Run Them, James H. Stephenson.
Farm Machinery and Farm Motors, J. B. Davidson and L. W.
Chase.

Digitized by

Google

894 AGRICULTURAL ENGINEERING

Power and the Plow, L. W. Ellis and Edward A. Rumley.
Physics of Agriculture, F. H. King.
The Gas Engine, F. R. Hutton.
Gas Engine Principles, Rodger B. Whitman.
Farm Gas Engines, H. R. Brate.

The Use of Alcohol and Gasoline in Farm Engines. U. S. Dept.
oi Agr. Farmers' Bulletm 277.

Digitized by

Google

PART SEVEN— FARM STRUCTURES

CHAPTER LXII
INTRODUCTION; LOCATION OF FARM BUILDINGS

The study of farm buildings is important to those engaged
in agricultural pursuits, for the following reasons:

1. The amoimt of capital invested in farm buildings is
large.

2. Convenient farm buildings conserve labor.

3. Comfortable buildings for live stock conserve feed and
insure maximum production.

4. The health of farm animals and the quahty of the
products produced by them depend in a large measure upon
the sanitation, ventilation, and Hghting of the farm buildings.

Capital Invested in Farm Buildings. The fixed capital of
farms is divided by the 1910 Census into land, buildings,
implements, machinery, and live stock. The relative impor-
tance of these is shown by the percentage which each bears to
the whole.

Land 69.5 per cent

Buildings 15.4 per cent

Live stock 12.0 per cent

Lnplements and machinery 3.1 per cent

Conservation of Labor by Convenient Arrangement of
Farm Buildings. It is difficult to estimate the saving of labor
which will result from buildings convenient in themselves and
in their relation to one another. This, however, is an impor-
tant matter, because the loss on accoimt of inconvenience is
accumulative, and the aggregate for a year is large. Thus

395

Digitized by

Google

396 AGRICULTURAL ENGINEERING

the total distance covered in a year in walking 300 feet and
return four times a day is over 145 miles, and a saving of
30 minutes every day for a year is equal to nearly 19 days
of ten hours each. As far as possible the arrangement of farm
buildings should follow the principles incorporated in modem
shops and factories.

Comfortable buildings conserve feed to such an extent
that under modem conditions it is practically impossible to
produce meat or dairy products profitably without them. It
is true that authorities differ on this point. Some maintain
that protection from temperature changes is not of great im-
portance for successful beef production, but all agree that
protection from wind and wet is essential. Sanitary farm
buildings maintain the health of farm animals. Pure air is
as essential as good food. Poor ventilation furnishes the
best conditions for disease germs to flourish, while proper
Ughting dispels disease by destroying germs. The best
quaUty of milk cannot be produced in unsanitary bams.

Laying Out the Farm. By the laying out of the farm is
meant the arrangement and location of the fields, buildings,
and lots. This is a subject which naturally precedes the
arrangement and design of farm buildings, for it is well-nigh
impossible to consider one farm building fully without taking
into account its relation to other buildings and to the fields
of the farm on which it is located.

The proper arrangement of a farm is fundamental in
securing convenience, system, and economy in its operation
and management, and may determine the success or failure
of the enterprise.

In laying out the farm an almost endless niunber of condi-
tions must be considered, among which may be mentioned:

1 . The amoimt of good and poor land.

2. The location of the hills.

Digitized by

Google

FARM STRUCTURES 397

3. The location of the woodland.

4. The location of water.

5. The natural drainage.

6. The original shape of the tract.
The features to be desired are :

1. Convenience of access, economy of fencing, and con-
venience of rotation, of the fields.

2. Convenience of relation to one another, to the fields,
to the lots, and to the highways, of the buildings.

A map of the farm showing location of buildings, lots,
fields, streams, roads, and draining is very helpful. Each

fig. 263. An inconvenient arrangement oi larm Duiiaings.

field should be designated by a particular name or number
and the exact acreage indicated. Such a map is extremely
useful in planning the operations of the farm, the rotations,
and in calculating the amounts of fertilizers, seed, etc.

Digitized by

Google

898

AGRICULTURAL ENGINEERING

A OOOO

Lbocno :

from Town —
Movtwno VWorh -

To nSk* ..«.

To illustrate the great differences to be observed in farm-
stead plans, attention is called to the two accompanying
sketches. The first of these (Fig. 253) is the plan of a farm-
stead just as it is at the present time. To do the morning
• chores on this farm, — ^tending to the horses, cows, and hogs —
it is necessary to walk 2400 feet outside of the buildings.
Besides this bad feature notice how inconveniently the garden

is placed from the
house. The well, also,
instead of being be-
tween the house and
bam, is beyond the
bam.

Compare this plan
with the next. The
house is 150 feet from
the road and the bam
is 200 feet from the
house, which is not too
close when located in
the right direction.
The prevailing winds
are either from the
northwest or south-
east, and the odors
from the bam are seldom carried toward the house. The
implement and wagon shed also includes the shop and
the milkhouse. If the well could be located near this shop,
so much the better, as at this point a gasoline engine could
be used to do all the light work. In doing the morning work,
a man needs to walk only 900 feet, a saving of 1500 feet
over the former plan.

RjBUO

Hu»MW«Y.

Fig. 254. A good arrangement
buildings. The lines of travel in doing
work of the farm are indicated.

of farm

Digitized by

Google

FARM STRUCTURES 399

Principles of Location. In locating the farm buildings, it
is well to incorporate as many as possible of the following
principles in the plan:

1. Have the buildings near the center of the farm, giving
due consideration to other advantages.

2. Needless fences should be avoided, on account of first
cost and the cost of maintenance.

3. A pasture should be adjacent to buildings.

4. The buildings should occupy the poorest ground.

5. The buildings should be located with reference to the
water supply.

6. The buildings should be on a sUght elevation when-
ever possible.

7. A southwest slope is desirable.

8. The soil on which buildings are to be placed should
be dry and well drained.

9. A timber windbreak should be secured.

10. A garden plot should be near the'house.

11. The buildings should not be located on high hills,
because of difficulty of access from fields and roads.

12. The buildings should not be placed in low valleys,
on accoimt of the lack of air and good drainage and the
danger from frost.

13. The buildings should be located on the side of the farm
nearest the school, church, or town.

14. The house should not be less than 100 feet from the
highway.

15. The bam should be about 150 to 200 feet from the
house, and not in the direction of the prevailing winds.

16. The bam should be in plain view from the house.

17. The lots should be on the farther side of the bam
from the house.

18. Several views from the house are desirable.

Digitized by

Google

400 AGRICULTURAL ENGINEERINO

19. All buildings should serve as windbreaks.

20. The shop and machine shed should be convenient to
the house, the bam, and the fields.

Two general systems of arranging farm buildings have
been developed in this country. For want of better terms,
they may be dedgnated as the distribtded system, in which a
separate building is provided for each kind of stock or for
each purpose to which it may be devoted; and the concenn
trated system, in which everything is placed under one roof as
far as possible, or the buildings are at least connected. The
advantages of the first system may be stated as follows:

1. A greater amount of lot room is possible.

2. Different kinds of animals are separated.

3. There is less destruction in case of fire.

4. It is more economical for the storage of certain crops
and machinery.

5. Better lighting is secured: wide bams are necessarily
dark.

In turn, the following arguments maybe advanced for the
concentrated system:

1. The first cost is less: needed space is secured with the
minimiun of wall surface.

2. There is less expense for maintenance.

3. It is more economical of labor.

4. Better fire protection can be provided.

5. Manure can be handled to the best advantage.

6. It provides a very imposing structure.

It is to be expected that opinions and tastes will differ, as
well as conditions, and all of these will determine the best
arrangement for any particular location. Most farmsteads
are the result of growth and development, and for this reason
are not what they would be if built entirely at one time. As
changes are made and new buildings constructed it is well to

Digitized by

Google

FARM STRUCTURES 401

keep in mind the desired features and to approach the ideal as
far as possible.

In commercial life it has often been fomid a matter of
good business to dismantle certain buildings designed for
manufacture and entirely rebuild them. There are, no doubt,
many farms so equipped that it would be a good business
investment to entirely dismantle the existing buildings and
rebuild in such a way as to insure a more economic operation.

QUESTIONS

1. Give four reasons why the study of farm structures is impor-
tant.

2. What percentage of the fixed capital of the farm is invested in
fann buildings?

3. Explain how a convenient arrangement of farm buildings con-
serves labor.

4. In what way will comfortable buildings conserve feed?

5. How is the quality of dairy products influenced by the character
of the farm buildings?

6. Upon what general conditions will the layout of the farm depend?
7 What are the principal features to be desired in the layout oi

a farm?
. 8. What are some of the principles involved in laying out the farm?
9. Discuss the distributed system of farm buildings.
10. Discuss the concentrated system of farm buildings.

Digitized by

Google

CHAPTER LXIIl
MECHANICS OF MATERIALS

Definitions. Mechanics is that science which treats of
the action of forces upon bodies and the effects which they
produce.

Statics is that division of the science of mechanics which
treats of the forces acting on a body at rest, or in equilibrium.
In architectural design, statics is the principal branch of
mechanics to be considered, as nearly all the forces involved
are those of rest.

Action of a Force. A force acting upon a body tends to
produce motion in two ways:

1. It tends to produce motion in the direction of the
force.

2. If a point of the body be fixed, it tends to produce
motion about that point.

Condition of Equilibrium. Since a force acting upon a
body tends to produce motion in two ways, the following
conditions must be filled in order that equiUbriiun exist:

1. The resultant of all the forces tending to move the
body in any direction must be zero.

2. The resultant of all the forces tending to turn the body
about any point must be zero.

The moment of a force about a point is the product of the
force into the perpendicular distance from the line of the
force to the point.

Moments tending to produce clockwise rotation are called
positive moments, and those tending to produce counter-
clockwise motion, negative moments.

402

Digitized by

Google

FARM STRUCTURES

4a3

Tension
Fig. 255. A
sketch illustrat-
ing a tensile
stress.

Eqxulibrium of Moments. The forces acting upon a body
are in equilibrium when the algebraic sum of their moments
about any one point is equal to zero.

Stress. A stress is the resistance offered by a rigid body
to an external force tending to change its
form. A rope suspending a weight is under
stress. If a section of the rope be taken at
any point, the force exerted by the part of the
rope on one side of the section on the part on
the other side to prevent the rope from part-
ing or breaking, is termed the stress ai a section.
The word strain is often used incorrectly for
stress, but strain is the change of form pro-
duced by a stress. Simple stresses are of three kinds, — ten-
sile, compressive, and shearing.

Stresses are measured in pounds or tons in coimtries using
English units. The pound is the more often used.

Tensile stresses are those tending to pull
the object or material in two, or to stretch it.
A rope suspending a weight is under a tensile
stress. A tie rod in a truss is subjected to
tensile stress.

Compressive Stresses. Compressive stresses
are those tending to crush the object or ma-
terial, as the load that is placed on a column
or on a foundation.

Shearing Stresses. Shearing stresses are
those tending to slide one portion f , t f i -, -h — ,f 1^^=^
of the material over another, or j,,^ 257. a sketch niustrat.
when there is a tendency to cut. *°« * shearing stress.
The stress on riveted joint is a good example.

Complex Stresses. Complex stresses are those formed
by a combination of simple stresses. The stresses in beams
are usually complex.

777?

Compreasion

Fig. 266. A
sketch illustrat-
ing a compres-
sive stress.

Digitized by

Google

404 AGRICULTURAL ENGINEERING

Unit Stress is the stress per unit area. Stresses are
usuaUy measured in pounds, and areas in square inches. The
total stress divided by the area of cross-section in square
inches will give the unit stress.

"-I

when P «* total stress in pounds.

A » area of cross- secticm in square inches.
S » unit stress.

This rule is applied only when the total stress is uniformly
distributed and the stress is a simple stress.

Elasticity. Most bodies when subjected to a stress will
be deformed. The amount the body is changed in shape is
termed the deformation. An elastic body will regain its
former shape when a stress is removed, if it has not been too
great. Up to a certain Umit the amount of change in shape is
proportional to the stress. If the unit stress be increased to
such an extent that the material will not regain its original
shape after being deformed, the stress has passed beyond the
elastic limit of the material.

Ultimate Strength. If the unit stress of any material be
increased until rupture or breakage occurs, the stress pro-
ducing the failure is the ultimate strength of the material.
If the failure be produced by the tensile stress, the ultimate
tensile strength is obtained. In Uke manner the ultimate
compressive and shearing strengths are obtained. The
breaking load divided by the original cross-section gives the
ultimate strength.

Working Stress. The greatest stress allowed in any part
of a framed structure is called the working stress of that part.
In turn, the working strength of a material to be used for a
certain purpose is meant the highest unit stress to which
the material ought to be subjected when so used.

Digitized by

Google

FARM STRUCTURES

405

Factor of Safety. The factor of safety is the ratio of the
ultimate strength to the working stress of a material.

when S = ultimate strength, s = working strength, f — factor of safety.

The engineer in charge of design is called upon to decide
the factor of safety to be used.

The factor of safety should (1) be much below the elastic
limit, (2) be larger for varying loads, (3) be larger for non-
imiform materials.

Factors of safety for variovs materials.

Materials

For steady

stress.
Buildings

For varsring
stress.
Bridges

For shocks.
Machines

Timber

8
15

6
4
5

Brick and stone

Cast-iron

Wrouidit iron

Steel

This table is taken from an architect's handbook, and the
factors of safety here recommended are nearly twice as large
as are commonly used in designing farm structures.

QUESTIONS

1. Define mechanics. Define statics.

2. In what two ways does a force acting on a body tend to produce
motion?

3. What are the two conditions for equilibrium?

4. Define moment (d force.

5. When does an equilibrium of moments exist?

6. Define stress. Define strain.

7. Describe a tensile stress. A compressive stress. A shearing
stress. A complex stress. Define unit stress.

8. Explain what is meant by the elastic limit of a material.

9. Define ultimate strength. Working stress. Factor of safety.
10. Upon what conditions will the size of the factor of safety depend?

Digitized by

Google

CHAPTER LXIV

MECHANICS OF MATERIALS AND MATERIALS OF
CONSTRUCTION

The Strength of Beams. The strength of a beam or its
ability to support a load depends upon three principal factors :
(1) The way the beam is stressed, or the way the load is
appUed or distributed and the beam supported; (2) the way
the material is arranged ; and (3) the kind of material. These
factors are represented by the maximum bending moment,
the m^vliLS of section, and the modulus of rupture.

The Bending Moment. The bending moment is a meas-
ure of the stresses acting on a beam. Suppose a beam to be
fixed soUdly at one end, as would be the case if it extends
into a soUd wall, and a load or a weight to be suspended at the
extr^kne end, as shown in Fig. 258. It is to be noted that the

greatest stress in the beam would
be at the point where it enters
the wall. The force would tend
to rotate the beam about a point
in the beam where it enters the

a cantilever beam, *or a °beam Wall. The StrCSSCS produCed WOuld

tre'rcuoroi^l^?idTt tSe'f^ee tend to pull the material m two
®°*** at the upper side and to crush it

on the lower. If the weight be placed somewhere between
the wall and the end, the stress on the beam would be Jess
than in the first instance; in fact, the stress would be in direct
proportion to the distance from the wall to the weight. The
stress would also be in direct proportion to the size of
the weight. Thus the tendency to break the beam, or the

406

Digitized by

Google

FARM STRUCTURES 407

stress at the wall, would be twice as great for a 20-pound
load as for a 10-pound load. It is to be noticed that the stress
would be greater at the point where the beam enters the
wall than at any other point; or, in other words, the maxi-
mum bending moment would exist at that point.

Expressed in the form of a formula:
B M = W L

where B M is the maximum bending moment, W the weight, and
L the length of beam in inches.

If the beam be supported at
both ends or extend into the wall
at both ends, themaximiun bend-
ing moment would have an entire-
ly different value; thus, for a thf ?ction'of a^cot'e^?rafedt^^^
beam resting in supports at both '^' ^^°*^'* ^^ "^ "^"^^^^ ^^""•
ends with a load at the center,

BM = J^WL

If the load be imiformly distributed over the beam, then
B M = H W L

The Modulus of Section. It is generally known that a
2x4 piece of wood will support a greater load when placed on
edge than when laid flat. The modulus of section is simply
a measure of the strength of a beam according to the arrange-
ment of the material. Thus, for a beam with a rectangular
cross-section,

M S = ^
6

where M S is the modulus of section, b the width of the beam in
inches, and d the depth of the beam in inches.

Thus it is seen that a 2x4-inch beam is twice as strong
when set on edge as when laid on the flat; for, when placed
on edge,

M* 2X(4X4) 32

M S = -—- = =— -

6 6 6

Digitized by

Google

408

AGRICULTURAL ENGINEERING

If placed on the flat,

_ ^ ^ W 4X(2X2) 16

6 ^ ^

or just one-half of the value previously obtained.

The Modulus of Rupture. The modulus of rupture is a

measure of the strength of the material to resist transverse

or bending stresses. Thus oak is stronger than pine. The

modulus of rupture is obtained by test. The following table

f iLmishes the values of the modulus of rupture quite generally

used. All of the values are per square inch of cross-section.

White pine 7,900

Yellow pine 10,000

Oak 13,000

Hickory 15,000

Cast-iron 45,000

Mild steel 65,000

Formula for Beams. The general formula for beams may

now be stated as follows:

^ ,. modulus of selection X rupture modulus

Bendmg moment = :: — ;:

factor of safety

This formula may be used in calculating the strength of
beams, but it is given here principally to explain how the
strength of beams varies. The following tables give the
strength of colimms or posts and of beams.

Safe Strength of White Pine Beams. The following
table gives the safe loads for horizontal, rectangular beams

Span in

feet

Depth of

beam

720

540

432

360

308

980

735

588

490

420

1280

960

768

640

548

480

2000

1500

1200

1000

857

750

2880

2160

1728

1440

1234

1080

3920

2940

2352

1960

1680

1470

Digitized by

Google

FARM STRUCTURES

409

one inch wide with loads uniformly distributed. If the load
be concentrated at the center, divide by two.

For oak or Northern yellow pine, the tabular values may
be multiplied by 1 J^; for Georgia yellow pine, by 1^.

For a discussion of the materials used in the construction
of farm machinery, see Chapter XXXI.

Safe Load in Pounds for White Pine or Spruce Posts.'*'

ftisfl of post
ininohes

Length of post in feet

4x4

4x6

5}4 round.

6x6

6x8

6x10

7}4 round.

8x8

8x10

8x12

9}4 round.
10x10

7,680

11,520

12,350

19,080

25,440

31,800

24,220

35,450

44,320

53,180

40,000

62,500

7,033
10,550
11,730
18,216
24,290
30,360
23,380
34,300
42,480
51,450
39,000
55,400

6,533
9,800
11,180
17,352
23,140
28,920
22,540
33,150
41,440
49,730
37,860
53,960

8,700
10,490
16,490
21,980
27,480
21,660
32,000
40,000
48,000
36,800
52,520

15,620
20,830
26,040
20,820
30,850
38,560
46,240
35,730
51,080

Oak and Norway pine posts are about one-fifth stronger,
and Texas pine and white oak are one-third stronger.

Stone. Limestone and sandstone are the kinds of stone
generally used for building purposes. Granite is used to a
limited extent. Limestone is the most common stone used,
and when dense and compact is very durable. It often con-
tains certain substances which cause the stone to become
badly stained after being in use for a time. Limestone has
an average compressive strength of about 15,000 pounds per
square inch and weighs from 155 to 160 pounds per cubic foot.

*Kidder*s Pocket Book.

Digitized by

Google

410 AGRICULTURAL ENGINEERING

Sandstone of a good grade is an excellent building mate-
rial. It has a strength of about 11,000 pounds per square
inch and weighs about 140 pounds per cubic foot.

The densest and strongest stones are the most durable, as
a rule. A good stone will not absorb more than 5 per cent
of its weight of water when soaked in water for 24 hours.

Brick. Brick is a material quite generally used over the
country, and when of a good quality is quite satisfactory.
Brick should be of imiform size, true and square, and when
broken should show a uniform and dense structure. Good
brick will not absorb moisture to an extent greater than 10

per cent of its weight,
and the best will absorb
less than 5 per cent.
The crushing strength
of brick should exceed
4000 pounds per square
inch.

Hollow clay blocks
or tile are made of the

Fig. 260. Hollow clay building blocks. . , i • i

same material as bnck,
and should have the same characteristics. Clay blocks are
lighter than brick, and so the cost of shipping is less. They
cost less by volume, and more wall can be laid in a given time
than with common brick.

Lime. Lime is used in mortar where the greater dura-
bility and strength of cement mortar are not needed. Quick
lime should be in large lumps and should be free from cinders
and dust. When slackened with water it should form a
smooth paste without lumps or residue. Lime mortar is
usually made of 1 part of lime to 2 or 3 of sand.

Portland Cement. Portland cement is now generally used
in the making of mortar and concrete. It should be finely

Digitized by

Google

FARM STRUCTURES

411

ground and should set or harden neither too quickly nor too
slowly. It should show a high tensile strength when hard-
ened and sufficiently aged. It should not check, crack, or
crumble upon hardening. Where cement is to be used in
considerable quantities it should be carefully tested by
standard tests.

Sands. Sand should be clean, durable, coarse, and free
from vegetable and other foreign matter. Coarse sand is
preferable to fine sand because the percentage of voids or
open space between the sand grains is less.

Concrete. In a general way concrete consists of mortar
in which there is imbedded more or less coarse material, Uke

Fig. 261. Material required to make concrete to the proportion of
1 part of cement, 2 parts of sand, and 4 parts of broken stone.

gravel or broken stone, called the aggregate. Thus it is seen
that if the aggregate be good, durable material and the mortar
be sufficient in quantity to surround all of the aggregate, the
whole will be as strong as the mortar. In preparing concrete,
therefore, it is desirable to obtain as dense a mixture as is
practical.

The mixtures indicated in the following table are in com-
mon use, and the iamount of material required to make a
cubic yard of concrete in each case is also given.

A rich mixture is used for beams, colimins, and water-tight
constructions.

Digitized by

Google

412 AGRICULTURAL ENGINEERING

Material for one yard of concrete of different proportions.

Mixture

Proportions

Cement, bbls.

Sand. bbla.

Gravel, bbla.

Rich

1:2:4
1:2^:5
1:3:6
1:4:8

1.57

1.29

1.10

.85

3.14
3.23
3.30
3.40

6.28

Medium

Ordinary

T/eAn

6.45
6.60
6.80

Additional data: 1 bbl. of Portland cement weighs 376 lbs.; a
sack, 94 lbs. A barrel contains 3.5 cu. ft. between heads. Concrete
wei^ about 150 lbs. per cu. ft.

A medium mixture is used for thin foundation walls and
for floors and sidewalks.

An ordinary mixture is used for heavy walls which are
not subject to heavy strains.

A lean mixture is used for heavy work where the material
is subjected to only compressive stresses.

Reinforcement. Concrete is a very good material to

carry compressive stresses. Concrete and steel have very

. ,^w»., nearly the same coefficient of ex-

i.l....J pansion for changes in tempera-

^^ ture. This makes possible the use

Fig. 262. Sketch showingr of a combiuatiou of j thcse mate-

the proper location of steel *n i . i

a concrete slab to resist tensile nals to the vcry Dcst advantage

stresses due to bending. . i .i i. . ,. rm

m bmlding construction. The
steel is placed in position to resist tensile stresses to the
best advantage, and the concrete is poured around it.
When used economically the cross-sectional area of the steel
is equal to J4 to 1 per cent of the cross-sectional area of the
beams. The steel is usually placed from ^ to 1 inch be-
neath the surface of the concrete, in order to be thor-
oughly protected from corrosion.

Digitized by

Google

FARM STRUCTURES 413

QUESTIONS

1. Upon what three factors does the strength of a beam depend?

2. Define maximum bending moment.

^ 3. What is the maximum bending moment for a beam X20 inches

long and loaded at the center with 1000 pounds?
k 4. Define modulus (d section.

5. What is the modulus of section for a 2x6?

6. Define modulus of rupture.

^ 7. What is the modulus of rupture for white pine? Oak? Cast

iron?

8. Give the general formula for beams.

9. What load will a 2x6 white pine beam carry if the beam be 10
feet long and the load be concentrated at the center? If the load be
uniformly distributed?

10. Give the principal characteristics of the following building
materials: stone, brick, lime, Portland cement, sand, concrete.

11. Explain rich, medium, ordinary, and lean mixtures, and the
I use of each.

12. Explain the principles involved in the reinforcing of ccmcrete.

Digitized by

Google

CEjl^TTSSL IXT

n/vififs isr>QKS maft, of «C!«ir«'. be i

If itiiM, ]>ruiui0t is H^?t icipcftiBEt. aul a vdl-
drwmd kcstkn dioaid atvxj? be aekcted. If the aofl is of
* pr^>«jfi or gnnreOj sstaiey it win make a inoffe de^^

Tffff of Hof Hiwwf Thoe are two ^enenl types of
bog b^/iMai m eofumon use. The first tjrpe is the imUxiiiiud
in cdmy bf^ hffwse, or eol, as it is sometiiDes caDed, wfaidi is
tmuMy made pr^table and of soflkieiKt sixe to acoommodate
mm wm at Uammmg time or one litter of pigs as they grow to
maturity.

The necond type is the large or eonctniraUd hog house,
flrmu^imes called the combined hog house, or piggery, and pro-
vUUm several pens under one roof. This type of building is
of more elaborate construction, and in many instances special
mm is uso<l in the construction to secure a warm building for
farrowing early litters.

Advantages of the Colony House. There is much differ-
mm) of opinion, even among practical hog raisers and breed-
t^THf In n%ard to the relative merits of the two types of hog

414

Digitized by

Google

FARM STRUCTURES 415

houses which have been described. The advantages of the
individual or colony house may be summarized as follows:

1. Each sow is free from disturbance at farrowing time.

2. Each Utter is reared by itself, and too many pigs are
not placed in a common lot.

3. The house may be placed at the opposite end of the
lot from the feed trough, thus requiring the hogs to exercise.

4. There is less danger of spreading disease, owing to the
fkct that each family is quite effectively isolated.

5. If the location of the house becomes imsanitary, it
may be moved.

Advantages of the Large Hog House. The following
advantages may be claimed for the large or concentrated
hog house.

1. This type is almost essential for early litters in north-
em cUmates. It is possible to construct a warmer building to
begin with, and, if necessary, artificial heat may be provided
by means of a stove orieating plant.

2. It saves time in handling and feeding the pigs. In
other words, less time is lost going from pen to pen. The
distribution of feed and water becomes a big task where there
are many pens to look after and where they are located at
some distance from one another.

3. The concentrated house saves fencing.

4. The large house is generally of more durable con-
struction and of better appearance, adding thereby to the
value of the farm.

5. It permits of larger pastures, which are more con-
venient to renew or cultivate when rotated with other crops.

Both types of houses are successfully used by practical
men, and the type to be chosen must depend upon local condi-
tions and individual tastes.

Digitized by

Google

4ie

AGRICULTURAL ENGINEERING

Dimensions. A farromng pen should contain from 40
to 140 square feet of floor. A common size is 8 by 10 feet.
Stock hogs should have 6 to 12 square feet of floor^ varying
with their age. A farrowing pen usually has an outside pen,
also, having an area of from 128 to 160 square feet or more.

Fig. 268. Front elevation of the "A" type of colony or portable
hog house. (After Wisconsin Exp. Sta.)

B feet of air space per hog is not taken into consider-
^ortable or individual hog houses are usually 6 by 8
by 8 feet.

ventilating flues are provided, about 8 square inches
section should be provided for each grown animal.

Digitized by

Google

FARM STRUCTURES

417

THE INDIVIDUAL HOG HOUSE

Construction. The individual hog house is constructed
in a variety of shapes, of which the more general are the
A-shaped house and the shed- and the gable-roofed houses.
There does not seem to be a great difference in the merits of
one shape over the other.

The A-shaped house has the walls and roof combined. It
is usually made of 1x12 boards, with the cracks covered with
battens. The door should be about 2 feet wide and 2 feet 6
inches high. A small window is usually located at each end
of the house. A small ventilator in the ridge of the roof is
desirable. It is recommended that the door be covered with
burlap to prevent drafts in cold weather. Some breeders

::--!*

-r T
I
I
I

1
I

■--"-- f

^;r^.r.3.y

M-—

ZEEL

-&'cr-

14-

Fiff. 264. Side elevation of the house shown in Figr. 263.

Digitized by

Google

418

AGRICULTURAL ENGINEERING

prefer a cloth covering for the windows in place of window

glass.

This type of house is generally built on skids or runners,

which facilitate its moving from one location to another.

These nmners may best be made of 4 x 6 pieces, although

2x6 pieces are quite often used. Reinforced concrete skids '

have been used successfully for portable houses and have the

advantage of being free from decay.

Shed-roof House. The shed-roof house takes more

material than any other shape, and i? not generally made.

The floor, sides, ends, and roof may be so made as to be taken

apart for moving. Such construction might be an advantage

where the house is to be
moved a loi^g distance;
otherwise the use of skids
would be far more conven-
ient.

Gable-roof House. The

gable-roof portable house

has many advantages, the

.BnoYtjn^ principal one being the

Plgr. 265. End elevation of gable-roof COUVeuience of having CCr-
colony hog house. . . ,, ^ .. .

tarn sections of the roof
arranged for opening during mild weather and allowing the
direct sunlight to enter. This can be done more effectually

st and west and a section of the
le to open. One or both of the
L hinges to open during warm

r/?& J** c/'/rx/'
in iwo saciiono

is, and should be provided with
in like the A type of house.

Digitized by

Google

FARM STRUCTURES

419

THE LARGE OR CONCENTRATED HOG HOUSE

Large hog houses, as distinguished from the colony house,
vary largely in the arrangement of the windows, or the natural
lighting. The value of direct sunlight in the hog house is
generally appreciated.

Construction. Houses are usually located so as to extend
east and west, and when so located should have the half-
monitor or saw-tooth type of roof. The windows of this type
are so arranged that those in the lower row permit the sun
to shine into the first row of pens, and the upper row into
the row of pens on the north side of the building. Hog

Fig. 266. A floor plan of a large hog house.

houses built to extend north and south usually have gable
roofs, and a row of windows on each side.

There is much difference of opinion in regard to the rela-
tive merits of these two types of roofs. It is safe to say that
either will prove entirely satisfactory when properly con-
structed.

The half-monitor roof requires more material than the
gable-roof house. The upper part of the building is solely
for the purpose of letting sunlight into the back pens. Such
construction prevents the proper control of the temperature,
as there is a large pocket above into which the warm air may
lodge. The back tows of pens with this construction are
shaded more or less throughout the entire year. The open-

Digitized by

Google

420

AGRICULTURAL ENGINEERING

ings on the north side of the building are criticised severely by
some as being highly undesirable. On the other hand, the
principal redeeming feature of this type of house is that the
windows may be placed so as to do the most good.

The half-monitor roof is usually built about 24 or 30 feet
wide. It is desirable that the alley-way be 8 feet wide, to
permit a team and wagon to be driven through the house when
desired. The pens at either side may be from 8 to 12 feet

Fig. 267. A cross section of a hog house with half monitor roof. This
is located so as to extend east and west.

deep and about 8 feet wide. Fig. 267 shows a cross-section
of a house with the windows well arranged.

A cross-section of a gable-roof hog house is shown in Fig.
278. The sunlight enters the east windows early in the morn-
ing and travels across the floor, as the sun rises higher, until
nearly noon, when it is excluded until it begins to shine in
through the west windows. It is to be noticed that this type
of house uses less material than the first, owing to the fact that
there is not so much space in the upper part of the house.

Digitized by

Google

FARM STRUCTURES

421

The lighting of this type of house is sometimes augmented
by building a monitor above the alley-way and supplying two
additional rows of windows. This construction adds con-

Fig. 268. Cross section of a hog house with gable roof.

siderably to the -cost. A type of house which is being used
and developed in Iowa is one with a skylight running through-
out the entire length of the building. This system of Ughting

Fig. 269. Cross section of a hog house with a sky-light in the roof.
Direct sunlight strikes all parts of the floor during the day.

Digitized by

Google

422 AGRICULTURAL ENGINEERINa

is obviously the best of all, as a solid band of sunlight must
pass across the building every day, striking every part. With
windows, only spots of direct sunlight enter the building, and
even when great care is used in the design of the building this
light strikes but a relatively small proportion of the total
floor space. With this new type, the only portion of the entire
building not covered is the south end, and windows may be
provided to light this portion thoroughly.

The objection has been raised that this skylight would be
damaged by hail. An investigation shows that the loss of
greenhouse glass is not great, and it would be possible to pro-
tect the glass with a wire net if thought best. This construc-
tion is the cheapest of all, as the building may be built quite
low and the cost of the sash for the skylight is not much
greater than the cost of regular roofing materials. In some
instances it may be necessary to arrange a shade under the
skylight if the house is to be used much during the sunmier
months.

The Foundation. The foundation of a hog house need
not be heavy. A 6-inch concrete wall or an 8-inch brick
wall will be found adequate if placed on a 12-inch footing.
The foundation should extend below the frost line if the
building is to retain its shape well.

Floors. Earth, plank, and concrete are used for the hog
house floors. Earth is objectionable on account of the diffi-
culty of cleaning the house thoroughly. Plank is not desir-
able, for it furnishes a harbor for rats. Concrete makes a
very desirable floor, but has the objection of being cold.
Many practical breeders find that this objection has little
weight if the floor be placed upon thoroughly drained soil and
the hogs are provided with a Uberal amount of bedding. A
portion of the floor may be covered with boards. The usual
sidewalk construction should be used for concrete floors.

Digitized by

Google

FARM STRUCTURES 423

Walls. Drop siding upon 2x4 studding two feet on
center is usually used for the walls of the hog house. In
cold climates this construction with a layer of sheeting and
building paper between
should be used. Ship-lap
makes a very desirable
covering for the inside of
the house.

Clay blocks make a
very good wall, and are
cheap. No doubt they

will come into more gen- ^*«f- 270. a gable-roof hog house made
° oi concrete blocks.

eral use. Concrete walls

are very desirable, and, where gravel and sand can be secured
cheaply, are. much to be preferred over less durable construc-
tion.

The Roof. The usual method of constructing the roof is
to lay shingles or prepared roofing over sheathing in the usual
way. When nearly flat roofs are used, as with the half-
monitor types, prepared roofing is preferable.

Partitions. Partitions should be 33^^ feet high. Solid
partitions are advised by a few, as they keep the hogs separate ;
but open partitions intercept less light and when sows see
one another and the attendant they give little trouble from
interference or fright. Doors and troughs should be arranged
for convenience. The front partitions may be arranged to
swing over the troughs for handy cleaning and feeding.
Metal partitions, made of a metal frame with woven wire
fencing across, have not generally proven satisfactory. As
usually made they are not stifif enough, and generally give
trouble from bending out of shape. If made heavy, metal
partitions are quite expensive.

Digitized by

Google

424 AGBWULTUBAL ENGINEEBING

QUESTIONS

1. What are the easentials of a good hog house?

2. Where should a hog house be located?
8. Describe two types of hog houses.

4. Give the principal advantages and disadvantages of each type.

5. What is a good sice of farrowing pen?

6. Describe the following types ci individual hog houses: the
A-shaped, the shed-roc^ house, and the gable-ro<rf house.

7. Describe the arrangement of windows in the half-monitor and
gable-ro(^ hog houses.

8. Explain how a skylight may be used effectively to light a
hog house.

9. Describe the construction of the foundation, the floor, the walls,
and the roof ci a large hog house.

10. Discuss the construction and arrangement of partitions in a
large hog house.

Digitized by

Google

CHAPTER LXVI
POULTRY HOUSES

Location. Poultry houses should be located on well-
drained, porous soil. Siuiace drainage is important, and, if
necessary, it is always possible to modify the siuiace by
grading. A gentle slope to the south or the southeast is best.
A good windbreak is necessary, but there should be sufficient
air drainage.

Poultry houses should not be made a part of, or located
near, other farm buildings which may furnish a harbor for
vermin that will prey upon the young fowls. Poultry houses
may be quite close to the dwelling house, as in many instances
the women of the farm have the care of the poultry.

Dimensions. Modem poultry houses are usually built
on the imit system, that is, in sections for each flock of 25 to
100 birds. There has been much development of late years
in regard to the amount of air and sunlight admitted to the
poultry house; in fact, some houses are now built with one
side entirely open to the weather. The poultry house is sel-
dom built wider than 12 feet, although wider buildings may
be more economical as far^is space obtained for material used
in construction is concerned. The unit or section is usually
16 feet long.

Space for Each Fowl. The space for each fowl is usually
based on the area of floor siuiace rather than upon the cubical
space. Four to six square feet is usually allowed for each
fowl. The breed of the fowl, the range or size of the lot, the
climate, and the size of the house are factors to be taken into
account in deciding upon the amount of space for each fowL

425

Digitized by

Google

426

AGRICULTURAL ENGINEERINa

Small birds require less space, and the wider the range the
less the space required. More space is needed if close con-
finement is necessary on account of the weather; and if the
flock is large each individual bird will have more freedom,

f'"^i

«• |-i*

Rl-An

Fig. 271. Plan of an A-shaped colony poultry house. (la. Exp.
Sta. Bui. 132.)

requiring less space per fowl. In some instances the floor
space per fowl has been reduced to 23^ square feet.

It is a good rule to allow at least one cubic foot for each
pound of live weight, or from 5 to 20 cubic feet per fowl. If
enough height be provided for convenience in caring for the
fowls, there will be plenty of volume.

The Foundation. Poultry houses are of light con-
struction and do not need elaborate or expensive founda-
tions. CJolony houses are built upon skids. It is well that
the foundation of the nonportable houses be so constructed
as to exclude rats. If clay blocks or other masonry con-
struction be used, the foundation should extend below the
frost line, to overcome the damage which might be done by

Digitized by

Google

FARM STRUCTURES

427

Front Elevation

Fig. 272.

Front elevation of the house
shown In Fi^r. 270.

the heaving action of the frost. Masonry foundations are
to be preferred on account of their greater durability.

Walls. Any wall construction will be satisfactory so
long as it will prevent
drafts, retain the heat,
prevent the condensation
of moisture, and furnish a
smooth siuiace which may
be entirely freed from mites
and other vermin. The
following wall construc-
tions are generally used:

1. Walls made of a
single thickness of boards,
matched or battened.
Usually this construction
is too cold for anjrthing except southern climates. Building
paper may be used on the inside of the boards to make the
walls air-tight.

2. Double wall, same as above, except ceiled on the
inside. For general use this construction is fairly warm but
gives trouble from condensation of moisture.

3. Same wall as No. 2, but the space between the outside
and inside boards is filled with hay or other insulating mate-
rial. This is a very warm wall and gives Uttle trouble from
condensation.

4. Same as No. 3, except the inside sheeting is replace^
with lath and hard plaster. The latter gives a finish which
may be thoroughly disinfected when desired.

5. Masonry walls of concrete or clay building blocks.
Concrete makes a good wall for a poultry house if made
double.

Digitized by

Google

428 AGRICULTURAL ENGINEERING

6. Small houses may be covered with prepared roofing
laid over plain or matched lumber. Such construction is
warm and air-tight.

Floors. The cheapest floor for the poultry house is the
earth floor, but it is hkely to give trouble from dampness,
and is dusty and difficult to keep clean. Clay should be used
for the floor in preference to a loam soil. The earth surface
may be removed occasionally, or the entire floor may be

Fig. 273. Detail of nests for house shown in Fig 270.

replaced with new earth. Another objection to the earth
floor is that it is not vermin-proof.

Board floors are quite expensive, not very desirable, and,
to be warm, should be made double, with a layer of tar paper
between the two layers of boards. Board floors are likely
to form a harbor for rats.

Cement floors are the most durable, the easiest to clean
and disinfect, and are quite reasonable in cost. The objec-

Digitized by

Google

FARM STRUCTURES

429

tions to the cement floor are that they are very hard, cold,
and quite Ukely to be damp. A liberal use of Utter on the
floorwill overcome the first two objections. If placed on well-

Rdosts ^0 Dropping Board

Fig. 274. Detail of roosts and dropping board.

drained soil or on a porous foimdation of cinders or gravel the
floors ought not to give any trouble from dampness. Light
sidewalk construction makes a satisfactory floor.

Roofs. The roofs of poultry houses are made in various
shapes, the principal object sought with any style is to secure
plenty of windows with the least material. Although gable

Perspective -^ Framing

Fi9. 276. The frame of the house of Figs. 271 to 274.

Digitized byVjOOQlC

430 AGRICULTURAL ENGINEERING

roofs and half-monitor roofs are used to quite an extent, the
shed-roof house, extending east and west with the slope of the
roof to the north, is the prevaiUng type in this country.
This type of roof gives an abundance of room for windows
or muslin curtains. Where the house is made portable and
is to be moved among trees, as would be the case in an

Fig. 276. A photograph of the hoUse shown in Figs. 271 and 275.

orchard, the combination roof may be used to advantage.
This roof is Uke the shed roof, except a small portion is made
to slope to the front, reducing the height of the building.

Shingles may be used for the roof if the pitch is one-third
or greater, and building paper is used imder the shingles to
make the roof air-tight.

Digitized by

Google

FARM STRUCTURES

431

Prepared roofing is very satisfactory for the roofs of poul-
try houses, as it is air-tight, and when a good quality is used
its durability will compare favorably with shingles.

•rTU^^^ZV

4' ^tuds 2'-e' C«ril«f»

HEL

R«o»«*

Roo«^ft and Cenlef Horse can be
removed scparafely from •He r»roo-
pma bodre

End doer* may be omiftMl
if only ^ne secfi«n •f ^hc
hou*« te buiH-.

''Cuf^Oin

^Screen^

Plan

VcreetJ ^WwiSSf

Fig. 277. Plan of a farm poultry house with shed roof. (la. Exp.
Sta. Bui. 132.)

Windows. It is recommended by good authority that
there should be at least 1 square foot of window glass well
placed for each 16 square feet of floor space. The tendency
in the development of poultry-house construction has been
toward large glass or curtain fronts facing the south to let in
the warmth dining the day. The muslin curtains are
mounted on frames which permit them to be opened and
closed with ease. The openings for the curtains are covered
with wire cloth or netting.

Digitized by

Google

432 AGRICULTURAL ENGINEERING

Doors. The doors for poultry houses are found to be
the most convenient when hung on double-acting hinges.
Doors so himg can be pushed open even if the hands are filled.

Partitions. The partitions in continuous houses may be
made of boards or plaster. It is quite a common practice
to use poultry netting for the upper part, but the lower part
should always be made solid.

Ventilation. Although flues or the King system (see
chapter on ventilation) could be used to ventilate poultry

Pig. 278. Front elevation accompanyingr Fig. 277.

houses, ventilation is generally secured by means of cloth
fronts. For other farm buildings this means of ventilation
has not proven satisfactory, but has been successful with
poultry houses.

Types. Poultry houses are constructed after two plans:
(1) the colony system, consisting of isolated houses usually
made portable for each flock; and (2) the continuous system,
consisting of several adjoining units with pens for each.

Digitized by

Google

FARM 8TRVCTURE8 433

Development, however, has brought out the following three
popular types of houses:

1. The scratching-shed house is built in sections con-
taining two rooms, one for feeding and scratching and the
other for roosting and laying.

2. The curtaivr-front house, commonly called the Maine
Station House. In this construction the roosting and laying
room is in the rear of the scratching pen.

3. The fresh air or Tolman house. In this house the
front and parts of the sides are open. No more protection

Nests

Dettail- ^^
Reirsf^eictive

Nezsts

Figr. 279. Details of the nests of the house shown in Figs. 277. 278.

is secured for the fowl at night than during the day. This is
essentially a colony house, but may also be constructed on the
continuous plan.

Nests. The size of the nests will depend on the size and
breed of the birds, but should be 12x12 inches and 5 inches

Digitized by

Google

434 AGRICULTURAL ENGINEERING

deep for Leghorns or small fowls, and 14x14x8 inches for
Cochins or Brahmas.

Special Features. The poultry house should be wind
proof and free from drafts. A curtain placed in front of the
roosts will keep fowls warm in severe weather.

The nests should be dark, for hens lay better in such nests,
and the egg-eating habit is prevented.

Due protection against mites and lice should be provided
by making the house smooth and free from cracks on the
inside.

The nests, roosts, and droppings board should be remov-
able for cleaning or spraying. .

The roosts should be about 23^ feet from the floors, with
all bars at the same height, as ladder roosts cause the birds to

Figr. 280. Details of roosts of the house shown in Figs. 277 to 279.

crowd to the top bar. The roosts are best when about 2
inches wide and only the comers rounded, and rigid enough
to prevent one bird from disturbing others on the same bar.
The bars ought to be placed 12 to 14 inches apart and 8 to 12
inches allowed for each bird.

Digitized by

Google

FARM STRUCTURE!^ 436

QUESTIONS

1. Where should the poultry house be located?

2. How much space Ediould be allowed for each fowl?

3. Describe suitable foundations and Walls for poultry houses.

4. Discuss the construction of the poultry house floor.

5. What are the common types of roofs for poultry houses?

6. What materials may be used to good advantage in the con-
struction of the roof?

7. Discuss the management of windows for poultry houses.

8. What are the curtain fronts for poultry houses?

9. Discuss the arrangement and construction of doors .and parti-
tions.

10. What is the usual provision for ventilation in the poultry house?

11. Describe the usual types of poultry houses.

12. What should be the size of the nests?

13. Discuss some of the special features of poultry-house construc-
tion.

Digitized by

Google

CHAPTER LXVII
DAIRY BARNS

Essentials. The essentials of a good dairy bam may be
enumerated as follows:

1. Warmih. Dairy cows cannot be expected to produce
well unless comfortably housed. Cows protected from cold
require less feed.

2. Sanitation. Since dairy products are used for hiunan
food and since there is nothing that is so easily contaminated
with filth and disease as milk, the sanitation of dairy bams is
perhaps the most important factor in their construction.

3. VentUaiion. In order that cows shall produce well
and remain healthy, they must be provided with plenty of
fresh air.

4. Light. As explained in another chapter, adequate
natural lighting is necessary to cope with disease.

5. Dryness. Barns must be dry;^ damp bams breed
disease. Ample drainage must be provided.

6. Convenience in handling stock and feed must be con-
sidered.

7. Box StaUs. The bam must have provision for box
stalls, also pens for young stock and the bull, unless other
provision is made.

8. Storage room of suflScient capacity to suit conditions
must be provided for feed.

Types of Bams. Dairy bams may be classified according
to the method of handling the cows and also according
to the height of the building. The open feed room type of
dairy bam is arranged to let the cows run loose, and has but

436

Digitized by

Google

FARM STRUCTURES

437

a few stalls for use in milking. This style is well adapted to
certified milk production, as each cow may be groomed before
milking. An objection to this type of bam is that the cows
cannot be fed individually. It saves time in feeding, how-
ever, and the cost of construction is low.

The bam with stalls is the more common type. In com-
parison with the other system it may be said to be economical
of room and that it enables each cow to be fed her proper
ration. The cows are under better control, and it is easier to
save and handle the litter.

Shed or single-story constmction has the advantage of
being well lighted and easily kept clean, but is not economical

-J*/»/»c//.-*rt:-

Plg. 281. Floor plan of a modern dairy barn.

in constmction. This type usually has a monitor roof, with
a row of windows on each side. A loft or storage floor sup-
plies economical space and enables the bam to be kept warm
more easily. In this case all light must come from side win-
dows.

The Foundation. The foundation for a dairy bam should
extend below frost and should be on firm soil. The width of
footing may vary from 12 to 16 inches. An 8-inch founda-
tion wall of concrete or hard-burned brick is sufficiently
strong; a wall of rubble work should be wider. Sills should
be 12 to 15 inches above the fioor.

Digitized by

Google

488 AGRICULTURAL ENGINEERINQ

Walls. It is essential to have a wall diy and warm, and
smooth on the inside. Drop siding is ohm used on the out-
side of the studding and snHX>th cdling on the inside. In
mild climates a sin^e waU is satisfactory, but in north^n
climates a double waU must be used. A cement-plastered
wall on the inside is very suitable from a sanitary standpoint.
In extreme cold localities the walls may be stuffed with hay
or shavings. A monolithic, or solid, concrete wall is damp,
but a hollow wall is very satisfactory. These waUs are made
¥rith about a 4-inch air space between a 5-inch outer wall and
a 3-inch inner wall, reinforced and tied together with iron or
steel headers or ties.

"Wnndows. Windows should be placed to give maximum
light; about 1 square foot of glass to 20 to 25 feet of floor
space is adequate.

Space Requiredo A common rule is to allow 1 cuUc foot
of space for each pound of live weight housed. For the av-
erage dairy cow 500 to 700 cubic feet is sufficient when there
is proper ventilation. The stalls should be from 36 to 42
inches wide, for average Qonditions. The cdling is usually
8 feet in the clear.

Floors. Cement floors are the most satisfactory, but
are condemned because they are cold. But if dry and pro-
vided ¥rith sufficient bedding, they should be satisfactory in
every way. They are by far the nK>st sanitary. Board floors
may be used but are not durable and are more difficult to
clean. No woodwork should be imbedded in cement floors.

Cork and wood blocks are used to some extent but have
not passed beyond the experimental stage.

The Roof. Shingles or a high grade of prepared roofing
maybe used.

Size of Gutter. The gutter is usually 14 or 16 inches
wide and 4 to 10 inches deep. The bottom may be level.

Digitized by

Google

FARM STRUCTURES . 439

crosswise, or sloping to one side. The latter is objectionable,
as cows sometimes slip in a gutter with a sloping bottom.
The gutter should have a slope lengthwise of 1/16 to l/lO inch
per foot for drainage.

Facing of Cows. Opinions differ as to the advantages of
facing cows in or out when two rows of stalls are used. Stalls
that face in are convenient in feeding, and the cows do not
face the light, which is said to be injurious to their eyes. Ven-
tilation may also be m6re effective. The opposite system

Fig. 282. Interior of a inodern dairy barn.

gives advantages in removing the litter and in milking and
handling the cows.

Mangers. The mangers for dairy bams are made of
plank, concrete, or sheet steel. Concrete mangers are more
sanitary and durable than wooden mangers, but are more
expensive. They should be made continuous, with a drain
at one end for cleaning. The back side of the manger must
be from 4 to 6 inches high, enabling the cows to lie down.
Mangers are usually about 3 feet in width over all. Box
mangers should be made removable, to facilitate cleaning.

Digitized by

Google

440 <

AGRICULTURAL ENGINEERING

Patented mangers may be purchased which rest on the floor,
having no bottoms, and which may be raised out of the way
for cleaning.

Ventilation. (See Chapter LXXXIV on this subject.)
Stalls. Stalls for dairy cattle vary in length from 4 to
5 feet, and in width from 3 to 4 feet. The requirements of
the different breeds in this respect vary widely. The length
refers to the distance from the manger to the gutter. A
stall 4 feet 6 inches long and 3 feet 6 inches wide is suitable
for average conditions.

Wooden stalls or partitions are being rapidly displaced
by metal ones. The modem stall, as shown in Fig. 282, is
made entirely of pipe or tubing, with bolted connections.
The size of pipe or tubing generally used has an outside
diameter of 1^ or IJ^ inches.

Tig. 288. CroBfl-section through stalls in a modern dairy barn.

Cow Ties. One quite satisfactory method of securing
cows in the stalls is by means of a strap around the neck
snapped to a ring in a chain extending between the posts
of the stall. This device permits of a reasonable amount
of freedom for the cow.

The stanchion, however, is the device more generally
used, and the later models of swinging stanchions leave little
to be desired. The old-style fixed stanchions were too
rigid, but the present forms are supported at the top and
bottom by short lengths of chain, giving greater freedom of
movement to the cow.

Digitized by

Google

FARM STRUCTURES 441

QUESTIONS

1. What are the essential features of a good type of dairy bam?

2. Describe the various types of dairy bams with reference to
methods of handling the dairy cows and the height of the building.

3. Discuss the oonstmction of the foundation for a dairy bam.

4. In like manner discuss the constmction of the walls and the
roof.

5. How determine the proper amount of window surface?

6. Discuss the construction of the floor.

7. How much space is required per cow?

8. What should be the size of -the gutter?

d. Discuss the relative merits of having two rows of stalls face in
or out.

10. What should be the size of the manger? Discuss its constmc-
tion.

11. What should be the dimensions of a stall for a dairy cow?

12. Describe the construction of suitable stalls.

13. Describe the chain cow. tie.

14. What advantages does the swinging stanchion offer as a cow tie?

15. Discuss the constmction of mangers for the dairy bam.

Digitized by

Google

CHAPTER LXVIII
HORSE BARNS

Some important features of horse-bam construction are:
1. The location should be prominent, as it is one of the
most used of farm buildings.

2. Good surface and underdrainage are necessary.

3. The bam should be well lighted.

4. Provision for sufficient hay and feed must be con-
sidered.

5. Vehicle storage is often needed.

-6"^

Fig. 284. Floor plan of a general farm barn.

Space. Each horse will require from 700 to 1000 cubic
feet of air space. The bam must be 20 feet wide for a single
row of stalls and 30 feet for a double row.

The foundation should be of stone, concrete, or hard-
burned brick, and should extend below frost with sufficient
width of footing. Piers of stone and concrete are often used.

Ceiling. The ceiUng of horse bams should be at least 8
feet in the clear.

442

Digitized by

Google

FARM STRUCTURES 443

Walls. The walls of horse bams need not be as wann
as those for dairy bams. The single wall is often considered
sufficient except in the most severe climates.

Floors. The floor may be of cement or plank, but clay
is often preferred for the front half of the stall, at least. A
shallow, covered gutter 2 inches deep is a good thing when
proper drainage can be provided.

Facing. The horses may be faced in or out, and the
same conditions apply that were mentioned under dairy bams.

The feed alley should be at least 3 feet wide, and a width
of 4 feet is desirable. A drive-way should be 8 feet wide
for a wagon or manure
spreader, and 12 feet wide
for a hayrack.

Stalls. Horse stalls are
usually made of two-inch
liunber. Pipe partitions
have been used to a very
limited extent. The ac-
companying sketch shows
a very satisfactory type
of stall where simplicity

of construction is desired. Fig. 285. a general farm barn with

Single stallsfor horses vary *^^'"'^''* '""'•

much in width, all the way from 3 feet 8 inches to 6 feet.
Five feet is considered a good width. Double stalls are
usually made 8 feet wide. A good length of stall is 9 feet
6 inches, measured from the front of the manger to the back
of the partition. Box stalls vary from 8x10 feet for a small
stall to 10x12 feet for one of liberal size. Stall partitions
should be about 6 feet high. The minimum width of the
alley behind the stalls is about 4 feet 6 inches.

MangerS) etc. Mangers are usually 2 feet wide and 3

Digitized by

Google

444

AGRICULTURAL ENGINEERING

feet 6 inches high. The floor of the manger should be about
15 inches above the floor.

Water troughs should be provided at a convenient point.

A harness room is essential in order to protect the leather
from stable fumes.

Hay carriers should be so installed as to enable the mow
to be filled readily.

Ventilation. (See Chapter LXXXIV.)

A 6

Cecik)n ihrv t>cb

Fiff. 286. Detail of conBtmction of a horse stall.

QUESTIONS

1. What are some desirable features in the horse bam?

2. How much space should be provided for each horse?

3. Discuss the construction of the horse bam with reference to
foundation, ceiling, walls, and floor.

4. How wide should feed alleys be?

5. Discuss the constmotion of horse stalls.

Digitized by

Google

CHAPTER LXIX
BARN FRAMING

Roofs. Several types of roofs are used in bam construc-
tion. The hip roof, which slopes from the four sides of the
bam to a point, is sometimes used for small bams. The
shed roof, which slopes only one way, is used for narrow bams.
The gable roof slopes in two directions and has gables, from
which it derives its name. Gable roofs are quite generally
used for bams. The curb, or gambrel, roof is much like the
gable roof, except each side of the roof has two pitches.
This type of roof is quite generally used for bams, and, in
addition to being quite rigid when property constructed, it
adds to the capacity of the haymow.

The Braced or Full Fnune. In this type of frame heavy
timbers are used, which are mortised and pinned together.
Many bam frames have been made after this style, but the
cost of the Imnber and the advantages of the plank frame
have caused an almost complete discontinuance of this style
of frame. When now used it is a modification of the old
form.

The Plank Frame with Purlines. In this type of bam no
attempt is made to keep the haymow free from framework,
and the long rafters are supported upon the purlines resting
upon posts throughout the frame. It is possible to keep the
mow free from framework directly imder the hay carrier
. track, and when so constructed it should not be inconvenient.
This type of a frame is not generally popular, but there can be
no serious objection to having the posts support the rafters
when they are properly placed.

445

Digitized iDy

Google

446 AGRICULTURAL ENGINEERING

Fig. 287. A model Wlngr Joist barn frame.

Figr. 288. A model Shawver barn frame.

Digitized byVjOOQlC

FARM STRUCTURES

447

The Wing Joist Frame. The Wing joist frame is made
entirely of 2-inch limiber. The frame consists of bents or
sections placed at intervals of 10 to 16 feet. The wall posts
usually have five pieces of 2-inch lumber below the mow, two
of which are continuous, and extend to the plate on which the
rafters rest. Girders running across the bam from post to
post are usually made of three pieces of 2-inch lumber. A

. Fig. 289. A sketch of the Winff Joist barn frame.

diagonal brace is placed from the top of the post supporting
the plate to an inside post to care for the thrust of the rafters.
Vertical siding is usually nailed to girts on the outside of
the posts. Plates for the rafters are made of two pieces of 2-
inch lumber in the form of a box. Iron rods are sometimes
used to brace the plates, but wooden braces are preferable.

Digitized by

Google

448

AGRICULTURAL ENGINEERING

owing to the fact that they are not only strong in tension
but are stiff and make a more rigid structm'e.

A cm-b roof is used, and the rafters, which are usually 2x6's
are strengthened at the curb by braces of inch boards or 2-
inch pieces cut to fit underneath. The rafters are usually
placed two feet apart on the larger bams of this construction.

;zr^:^is^7

- /a^3' -

- /o'-cr-

5"- 2-^5-

3^'-0'-

Fiff. 290. A sketch of the Shawver barn frame.

and should have diagonal braces to make the frame more
rigid. The Wing joist frame is not adapted to bams over
40 feet wide.

The Shawver Bam Frame. The Shawver bam frame,
as now constructed, consists of bents made up of 2-inch lum-
ber and placed 8 to 16 feet apart, on which the wall and rafter

Digitized by

Google

FARM STRUCTURES

449

coverings are placed. The Shawver frame is quite thor-
oughly braced in every way, as is shown by the accompanying
drawing. It is one of the standard forms of bam frames.

Steel Frames. Steel frames are now manufactured for
bams to a limited extent. The frame is made entirely of
steel in the shop ready to set up. They are generally more
expensive than the wooden frames.

Rotmd Bams. In some localities the roimd bam is very
popular. In general, it has two serious objections: (1) It
is quite diflScult to light a large roimd bam efficiently, and
(2) it is difficult to ar-
range the bam so as to
prevent a considerable
waste of space. A lar-
ger space can be enclosed,
however, within the wall
of the round bam than
in any other type using
the same amoimt of ma-
terial. Generally the
frame for the roimd bam
consists of studding,
spaced about two feet
apart, on which wooden
hoops of inch limiber
bent to the circle are
nailed. The roof is conical in form and is very rigid.

Fig. 291.

A sketch of a barn frame with
posts and purlins.

Most

roimd bams have a double pitch to the roof, with the rafter
cuts as for the Wing joist frame.

QUESTIONS

1. Discais the merits of shed, gable, and gambrel roofs for bams.

2. Describe the braced or full frame for a bam.

15—

Digitized by

Google

450 AGRICULTURAL BNGINSBRINa

3. Describe the oonstnictioii of a plank-frame bam with purlines.

4. Describe the oonstruction of the Wing jcMst fnune.

5. Describe the oonstruction of the Shawver plank frame.

6. What are the principal advantafces and disadvantages of a steel
bam frame?

7. What are the objecticms to a round bam, and its principal
adyantages?

8. Describe the usual method of framing a round bam.

Digitized by

Google

CHAPTER LXX
THE FARMHOUSE

The purposes of a farmhouse are:

1. To be a home, a meeting place of the family.

2/ To afiford protection.

3. To house the various goods and treasures of the family.

4. To provide a place for the administration of the farm.

5. To adorn the landscape.

In brief, the farmhouse should represent comfort, con-
venience, and economy.

Location. Consideration should be given to the follow-
ing features in the location of the farmhouse. The health-
fulness of the location should be given first consideration.
The site should provide water and air drainage, and on this
account a hillside slope offers many advantages. A well
should be within reasonable distance, if a supply of good
water is not supplied by other means. The bam should
not be too far away. A suitable place for a table garden
should be near. If located too far from the road, the house
will be lonely; if too near, privacy will be lost.

Designing the Farmhouse. Each house must be designed
to fit particular conditions and requirements. Plenty of
time should be used in preparing the plan. It is best to con-
sult a practical builder or architect. The preUminary draw-
ings should be drawn to scale in order that the planning may
be carried on more intelligently. Arrangements should be
made for possible improvements.

The Foundation. The foundation should be made of
goo d, durable masonry and should extend below frost for about

451

Digitized by

Google

452 AGRICULTURAL ENGINEERING

33^ feet, under most conditions. A brick wall 8 inches thick
is suflScient. Stone walls are usually made 12 to 18 inches
thick, according to the diflSculty of laying a wall of less thick-
ness. A concrete wall 6 to 8 inches thick is satisfactory.
A double wall is preferable because it is much drier. The
footing of the wall should be 6 to 8 inches wider than the
wall.

The Cellar. The cellar wall should extend at least 2 feet
above the ground line, to provide window space for adequate
lighting. Great care should be taken to make the cellar
wall as dry as possible. In some instances it is necessary
to plaster the outside, making it air-tight, and to lay a drain
tile line outside the footing. Often material can be saved
by building the cellar under the entire house. Such con-
struction is regarded as the most sanitary, if the cellar can
be kept dry.

If a furnace is to be installed, the ceiling should be suflS-
ciently high to provide room for the installation of the warm
air pipes.

THE PLAN

Th^ Dining Room. The dining room is often regarded
as the center of the farmhouse, and is in most instances used
as the Uving room. When so used it should be large enough
to contain not only the dining table, but also a library table
and a bookcase. The dining room should have plenty of
light, and a southern or western exposure is preferable.

The Kitchen. The kitchen of the farmhouse ought not
to be too large, if it is not used as the laimdry. Large
kitchens are the cause of unnecessary work. It is best to
arrange the kitchen with fixed cupboards and to provide a
sink and a convenient location for the range.

Digitized by

Google

FARM STRUCTURES

45B

The Pantry. Every modem house should have a panti*y,
which is most convenient when in connection with both the
kitchen and the dining room.

The Sleeping Rooms. The sleeping rooms may be as
small as 10x10 feet, but 12x14 feet is preferable. All
sleeping rooms should be provided with closets.

The Staircase. The staircase should be wide and not
too steep. Winding steps are to be avoided.

The Bafliroom. The bathroom may be as small as 6x8
feet, but 8x10 feet is regarded as a good size. It is most

iR.4Trk.o»^

^ Kjg OH fr «FK.Og|^.

Fiff. 292. First and second floor plans of a farmhouse.

convenient for the installation of plimibing when located
over the kitchen. The bathroom should have an outside
window for ventilation and light.

The Washroom. Although not usually provided, the
farmhouse should have a room where the men of the farm

Digitized by

Google

454 AGRICULTURAL ENGINEERING

may hang their extra coats and stable clothes. This room
should have lavatory facilities, enabling the men to wash
before entering the dining room.

The Laund^. Nothing is more useful in a well-designed
farmhouse than a room equipped as a laundry. When
adequate drainage can be secured, it is best located in the
basement.

QUESTIONS

1. What are the purposes of a farmhouse?

2. What are the requisites of a good location for a farmhouse?

3. What course should be followed in designing a farmhouse?

4. Discuss the construction of the foundation.

5. How should the cellar of a farmhouse be constructed?

6. Discuss the special features to be considered in the planning of
the dining room. The kitchen. The pantry. The sleeping rooms.
The bathroom. The washroom. The laundry room.

Digitized by

Google

CHAPTER LXXI
CONSTRUCTING THE FARMHOUSE

The Full Frame. The full frame corresponds to the full
frame for bams, made of dimension stuff, mortised and pinned
together, and in which the wall frames are raised as a unit.
This framing began to be displaced by the balloon frame
about 1860, and is now used only in a modified form. It
resists fire better thsyi the balloon frame, but may not be any
more substantial.

The Balloon Frame. The balloon frame is made of Ught
timbers, usually 2 inches thick and of varying widths. The
usual method of construction is to lay the sills, which may be
either a box sill of two 2x8 timbers, or a 4x6 timber. The
latter is halved in splicing at the angles and in the comers.
In the case of the box sill, one piece is laid on the wall and
the other on edge upon the first. The sills support the first-
floor joists, and from them, also, the studs, generally 2x4's,
are erected. The studs are made double at the comers and
at each side of the openings for doors or windows. They are
placed 16 or 12 inches o. c. (apart), the former being the usual
spacing. The studs extend to a double plate of two 2x4
scantUngs. They may be extended by a second piece placed
end to end and spliced with boards nailed on each side. The
joists for the second floor are supported by a girt or ribbon of
lx4-inch boards let into the studding. The studding at
each comer should have a lx6-inch brace notched in, or a
diagonal brace made from a^2x4 fitted between the studs. The
rafters for the attic are supported by the top plate and the
joists. A common practice is to use a box sill, lay the rough

Digitized by

Google

456 AGRICULTURAL ENGINEERING

flooring, and place the studding on a bottom plate nailed to
the flooring. To support the studding well, the rough floor-
ing should be laid diagonally; otherwise all the studding on
one side will be attached to one board.

It is very diflScult to prevent a one-and-a-half story
house from sagging, dup to the thrust of the rafters on the
plate, which cannot be held together.

Bridging. Bridging consists of diagonal strips, usually
1x3 inches in cross-section, nailed between the floor joists to

Fig. 293. A concrete block house representing a good type for the farm.

stiffen and strengthen them. Joists 8 to 16 feet long should
be bridged once; those 18 to 24 feet long, twice. The floor
should be leveled as the bridging is nailed fast. Two lOd
nails should be used at each end of the bridging pieces.

The studs should exttod from sill to plate in interior walls
the same as for outside walls, in order that shrinkage will
be uniform.

Digitized by

Google

FARM STRUCTURES 457

Sheathing. It is advisable to put sheathing on diago-
nally, as it then strengthens the frame very much, and the
extra cost of wasted material and labor is not great. The
wall sheathing is best when made of matched limiber.

Siding. The siding generally used is lap siding or weather
boarding. White pine is the wood generally used and is
regarded as very satisfactory. Drop siding, or so-called
patent siding, does not give a pleasing effect, although quite
satisfactory in other respects. Stucco or plastered walls
are very satisfactory when the plastering is on metal lath.

Lathing. The lathing should be carefully done, insuring
uniform spaces between the lath. The ^der carrying the
second floor joists should be set in far enough to enable the
lath to be nailed on strips and permit the plaster to clinch
around the lath. The direction of lathing should not be
changed, as there is a greater tendency to crack the plaster
when shrinkage occurs. An extra 2x4 should be used in each
comer so that the lath can be securely nailed in place.

The Roof. Thegreater the pitch of the roof the better, but
a half pitch makes a good roof. Wooden shingles are generally
used, those of cypress or red cedar being regarded as the best.
One thousand shingles laid 4 inches to the weather should
cover 100 square feet; but when laid 43^ inches to the weather
shingles will make a good roof. There are 250 shingles in a
bale, which is made 25 layers thick and 20 inches wide. Five
shingles should make a thickness of two inches. In laying
the shingles, joints should be broken twice, and plenty of
nails should be used in naiUng them on. Creosote and other
stains act as a preservative, but painting is not advisable.
Shingles may be dipped in oil with good results, for which
about 2 J^ gallons of Unseed oil are required per M.

The Exterior Finish. The following suggestions in regard
to the exterior finish may be useful. It should be plain, and

Digitized by

Google

468 AGRICULTURAL ENGINEERING

all filigree and turned work should be avoided, as it is not
diu'able. The cornice should be broad in order to protect
the walls. The use of a water table, with an edge under the
siding, insures a dry wall. Due im>vision should be made
above windows and doors for excluding water. Only the
best paint should be used, and perhaps there is none better
than pure white lead and linseed oil colored, when desired,
with the proper tints.

Plastering. Back plastering is thought to be very bene-
ficial in cold, wet climates, although not generally used.
Back plastering may be either between the studding or on
the studding, with the second layer of finishing plaster on
lath nailed to furring strips. The latter is regarded as the
better method, as there is a tendency for cracks to form from
shrinkage in the former method. Metal comer beads should
be used on all exposed plastered comers. The lime for lime
plaster should be slacked at least 24 hours before adding hair.
It should be then allowed to stand stacked up at least ten days
before using. Lime mortar may be made by adding to each
barrel of lime 3 barrels of sand and 1 to IJ^ bushels of hidr.

Hard plaster should be mixed according to the directions
furnished by the manufacturers. These plasters give a
harder wall and better protection against moisture.

The first coat of plaster is called the "scratch coat," the
second the "brown coat," and the third the "white" or
"skim" coat. Sometimes the third coat is omitted and the
walls are left rough or given a "float" finish, which is tinted
with a calcimine wash.

The Woodwork. Dust lines should be eliminated as far
as possible, and for this reason plain finish is desirable. The
architraves or casings may be mitered or fitted with blocks at
the comers; the latter does not show the effect of shrinkage as
badly as the mitered comers. The block placed at the

Digitized by

Google

FARM STRUCTURES 459

bottom of the casing to doors is called the plinth. The fol-
lowing are some additional suggestions:

1. Ample head room should be provided over stairs.

2. The sum of the rise and tread of steps should be about
n}4 inches.

3. "Winders, " or triangular steps, should be avoided.

4. A half post should be placed where the banister rail
joins the wall.

5. Dimensions of windows are given by the nimiber and
size of Ughts.

6. All sash should be carefully balanced. A good grade
of cotton cord is satisfactory.

7. The stop bead should be fastened with screws to per-
mit of adjustment and the removal of sash.

8. Doors are made in three grades. A, B, and C. Those
of standard size and dimensions are known as stock doors.
Veneered doors are usually more satisfactory than solid ones.

The Hardware. The butts, locks, knobs, and escutcheon
plates should be of good quality. The usual grades of hard-
ware are japanned iron, bronze plated, and solid bronze.
Much can be added to the appearance of a room by using
artistic, high-grade hardware. Loose pin, wrought-iron butts
should be used, as they are stronger than cast-metal butts.
Mortise locks are to be preferred over rim locks. Hinges
should be of ample size and should permit the door to swing
back against a stop on the wall.

The Finishing Woodwork. All woodwork should be
sandpapered with the grain before the application of any
finishing material. Nails should be well set and the holes
well filled with putty.

Two coats of hard oil or varnish make the cheapest but
the least desirable finish. The best finish is five or six coats
of shellac rubbed down. A wood filler may be used before

Digitized by

Google

460 AGRICULTURAL ENGINEERING

the first ooat. The final ooat should be of the best grade of
varnish. Floors are usually filled and varnished, or var-
nished with shellac and waxed.

Woodwork may be stained with water, oil, or spirit
stains. Water stains may go deeper but do not preserve
the wood as well as oil stains. Spirit stains are the most
expensive and must be carefully applied, as any lapping shows
badly.

QUESTIONS

1. Describe the fuQ frame for houses.

2. Describe the balloon frame for houses.

3. What is the objecticm to a one-and-arhalf story house as far as
framing is concerned?

4. Describe bridging and state its use.

5. When is it advisable to put sheathing on diagcmally?

6. What are the relative merits oi lap siding and drop siding?

7. What care should be taken in lathing a house?

8. Describe the construction and the materiab used in building the
roof.

9. What are some of the important features of the exteriw finish
of a farmhouse?

10. Explain what is meant by back plastering.

11. What care should be used in preparing plaster?

12. What does scratch coat, brown coat, and skim coat designate?

13. What is the composition of lime plaster?

14. What is a float finish to a plastered wall?

15. Discuss some important features of the woodworic.

16. What care should be used in selecting the hardware?

17. State how the woodworic may be finished.

18. What are the relative merits of the various kinds oi wood stains?

Digitized by

Google

CHAPTER LXXTT

THE sn.0

The Location of the Silo. In locating a silo, the matter
of convenience should be given first consideration. It should
be in direct communication with the feed alley in the bam.
A good location is some four to six feet from the bam and
joined to the feed alley by a chute extending up the entire
height of the silo. A door should close the passage-way
between the bam and the silo; and if the space be made to
accommodate the silage cart, it will not only make feeding
easier but will also provide a good place for storing the cart
when not in use.

Nearly all types of modem silos are best located outside
of the bam. As a rule, the silo does not need the protection
of a building, and the bam space may be more economically
used for other purposes. Furthermore, an inside silo is
inconvenient to fill, as it is difficult to deliver the fodder to
the ensilage cutter unless large driveways are ^provided,
which again are not economical. The odor of silage is
thought objectionable by some; but when the silo is located
outside of the building and connected with it only by a chute,
this objection is overcome.

The Size of the Silo. The modem silo is round. This
shape will resist the bursting pressure of the silage to the
best advantage and permit of a more perfect settUng of the
silage, which is very important. A round silo has two dimen-
sions, diameter and height. The diameter or cross-section
of the silo should be determined by the size of the herd.
From 13^ to 2 inches of silage should be fed from the silo

461

Digitized by

Google

462

AGRICULTURAL ENGINEERING

each day, after the silo is opened, to keep the silage fresh.
If a less amount is fed, a growth of mold is quite likely to
start and travel downward as fast as, if not faster than,
the rate of feeding.

The proper height of the silo is readily determined by
the length of the feeding season. It is an advantage, how-
ever, to have a deep silo. First, it is ecomonical, as addi-
tional volume is obtained without adding to the expense of
foundation and roof. Secondly, the silage depends upon the
exclusion of air for its preservation, and the extra weight of
silage in a deep silo promotes settling and assists in this
direction. Two silos of medium diameter are better than
one large one, as there may be times when it is desired to
feed the silage lightly.

Capacity of silos, and the amount of sUage that should he fed daily
from each.

Inside
diameter

Height

Capacity,
tons

Acres of com

of 15 tons

per acre

Amount.

to be fed daily.

pounds

12
12
12
12

• 34

67
74

80
87

4.5
5.0
5.3

5.8

755
755
755
765

14
14
14
14

30
32
34
36

91
100
109
118

6.1
6.7
7.2
7.9

1030
1030
1030
1030

16
16
16
16
16
16

30
32
34
36
38
40

119
131
143
155
167
180

8.0

8.7

9.5

10.3

11.1

12.0

1340
1340
1340
1340
1340
1340

18
18
18
18

36
38
40

196
212
229
246

13.2
14.1
15.26
16.4

1700
1700
1700
1700

Digitized by

Google

FARM STRUCTURES 463

The taual amount of silage fed per day to various classes of stock.

Kind of stock Daily rations, pounds

Beef cattle

Wintering calves 8 months old 15 to 25

Wintering br^ding cowa 30 to 50

Fattening beef cattle^ 18-22 months old

First stage of fattening 20 to 30

Latter stage of fattening 12 to 20

Dairy catOe 30 to 50

Sheep

Wintering breeding sheep 3 to 5

Fattening lambs 2 to 3

Fattening sheep 3 to 4

The preceding tables — which give the capacity of some of
the more common sizes of silos, the number of pomids of
silage which must be removed daily to lower the surface an
average of two inches, and an average ration for each of
various kinds of farm stock — should provide sufficient
information for deciding upon the size of silo to meet
ordinary requirements.

To explain the use of these tables, suppose silage is to
be fed to 10 head of dairy cows, 8 head of calves, and 40 head
of beef stock, for 200 days. The amount of silage required
per day will be about as follows:

10 dairy cows, 40 lbs. each 400 lbs.

8 calves, 20 lbs. each 160 lbs.

40 beef cattle, 20 lbs. each 800 lbs.

Total silage fed per day 1360 lbs.

Referring to the first table, it will be foimd that a silo 16
feet in diameter will furnish 1340 pounds of silage when 2
inches is fed daily; hence 36 feet, or 216 times 2 inches, will
be about the right height. Some allowance should be made
for settling.

The Essentials of a Silo. To preserve silage a silo must
have impervious walls which will not permit air to enter or

Digitized by

Google

464 AGRICULTURAL ENGINEERING

moisture to leave. The wall must be strong* and rigid enough
to resist the bursting pressiu'e of the silage, and sufficiently
smooth on the inside to permit the silage to settle readily.
In addition to these absolute essentials, there are many
featiu'es which add to the value of a silo and which should
be considered in its selection. Some of these featiu'es are
as follows:

1. It is highly desirable that a silo be as diu'able aiid
permanent as possible. All parts should be constructed
of materials which will insure a long term of service.

2. The silo should require a minimiun expenditure of
labor and materials for maintenance. This refers to the
adjustment of parts for shrinkage and expansion, repainting,
and the substitution of new parts for those which have
become decayed or otherwise useless.

3. The silo should have a wall which will prevent as far
as possible the freezing of silage.

4. The silo should be arranged in such a manner as to
be convenient for filling and for the removal of the silage.
This refers directly to the construction of the doors.

5. In some cases it is desirable to have a silo which may
be taken down and moved from one location to another.

6. A fire-proof silo may have the further advantage of
serving as a fire wall.

7. A silo should be sightly and should add to the appear-
ance of the farmstead.

8. It is an advantage to have a silo of simple construc-
tion, which may be erected with the minimum of skilled
labor, and in the construction of which there is little chance
for expensive mistakes.

9. Lastly, the silo of the lowest cost per unit of capacity,
^ving due consideration to the other features of merit, is the
most desirable.

Digitized by

Google

FARM STRUCTURES 465

If these essentials and desirable features are kept clearly
in mind, they will assist in comparing the various types of
silos now in general use.

WOOD SILOS

The Stave Silo. The commercial stave silo is in more
extensive use today, the country over, than any other type.
When properly made, the walls are air-and water-tight,
smooth and rigid, insuring
the preservation of the
silage.

The diu'ability of the
stave silo depends largely
upon the kind and grade
of the material used in its
construction. Redwood,
cypress, Oregon fir, tama-
rack, and white and yel-
low pine are the more
common kinds of wood
used, and their respective
merits and durabiUty rank'
about in the order given.

The Plain Stave Silo.
The stave silo made of
plain dimension lumber,
without b^ing beveled or

grOOVed,isnotsatisfactory. ^,^294. a good stave sllo well anchored.

Such a silo is certainly

cheap, but is very imstable. The walls are not as tight as
when the staves are matched, and as soon as there is a little
shrinkage there is a tendency for the staves to fall from place
into the silo, and then the whole structure collapses.

Digitized by

Google

466 AGRICULTURAL ENGINEERING

FvU-Length SUwe Silos. Full-length staves are desirable,
although more expensive. If spliced staves are used, the
method of splicing should be carefully examined. The
ends of the staves are fitted together by a U-shaped tongue
and groove; but the more common method of splicing con-
sists in inserting a steel spline about 1-16 inch thick in saw
cuts in the ends of the staves to be spliced.

The Foundation. The stave silo should be put upon a
good foimdation. The foimdation wall need not be wide, 12
inches being a good width, but it is well that it extend below
the frost line, or about 2J^ to i}^ feet. As the silo is likely to
be partly full during the coldest weather, the frost will not
be deep near the foimdation. Any masonry construction
may be used for the foundation, but concrete is especially
well adapted to the purpose.

Use of the Pit. It is doubtful if a pit is advisable with a
stave silo. The increased capacity so secured is economically
obtained; but there should not be a shoulder or bench inside
of the staves, as this will prevent the free settling of the silage.
If a pit is used to increase the capacity of the silo, and the
foundation wall is made flush with the staves on the inside at
the time of erection, it will be difficult to keep the silo on the
foimdation as shrinkage occurs.

Anchoring and Guying. The stave silo is a light struc-
ture and when empty is more or less at the mercy of the wind.
To guard against any possible damage from this source, it
should be carefully anchored to the foundation and guyed or
braced in all directions. The anchors to the foundation
should be at least four in number, and may be made of bars
extending into the masonry and bolted to the staves above.
The top of the silo should be carefully braced to any adjoin-
ing buildings. The guy wires or cables should run in
pairs to posts and builcUngs in opposite directions. These

Digitized by

Google

FARM STRUCTURES 467

guys are more effective when extending out some distance
from the base of the silo. The importance of this anchoring
and bracing is urged upon all.

The Roof. Every silo should have a roof: (1) It adds to
the appearance; (2) it strengthens and protects the staves;(3)
it is a big factor in preventing freezing; (4) it makes the silo a
pleasanter place in which to work. No attempt should be
made to seciLre ventilation; in fact, an attempt should be made
to retain the warm air in the silo as far as possible. Pre-
pared roofing of good quality makes a diu'able silo roof. It is
easily fitted to a conical form.

The Doorway. All commercial silos at the present time
have a continuous doorway, across which there are no obstruc-
tions except the crossties. This type of doorway offers
certain advantages in removing the silage, and is just as
satisfactory in other respects as the individual doorway. In
selecting a silo, it is well that an examination be made of the
door-fasteners to see whether or not the door makes a per-
fectly air-tight joint with the frame.

The Minneapolis Silo. The Minneapolis silo, or so-
called panel silo, is constructed of pieces of planks about 2
feet long, matched at the sides and beveled at the ends, set
into vertical studding. The whole is then boimd together
by hoops, which require practically no adjustment, as there is
little shrinkage lengthwise of the grain. Defective pieces in
this silo may be replaced by cutting them out, driving down
the pieces above, and inserting new ones at the top. This
tjrpe of silo is very rigid and stable.

MASONRY SILOS

The Concrete Silo. Concrete is one of the best materials
for silos. It is very important to make the concrete silo wall
impervious to air and water. The more common method of

Digitized by

Google

468 AGRICULTURAL ENGINEERING

doing this is to treat the inside of the wall| as soon as the
forms are removed, with a wash of pure cement and water
reduced to the consistency of paint. This wash thoroughly
seals the pores of the walls and prevents the loss of mois-
ture and the admission of air. A coat of coal tar has been used
with good results, and there are many patented compoimds
on the market which ought to be entirely satisfactory. In
several cases where no attempt was made to seal the walls the
juices of the silage apparently accomplished that result, after
two or three fillings, but this should not be relied upon.

Reinforcement. Another common mistake is the lack of
reinforcement or the improper use of reinforcement. The
blunting pressure of silage is considerable, about 11 pounds
per square foot for each foot of depth, as an average; and this
pressure must be fully cared for or the walls are sure to crack.

A mixture of one part of cement, two of sand, and four of
broken stone or screened gravel ought to make a good silo
wall. If good natural gravel and sand are at hand, a mix-
ture of one to five will be satisfactory.

The Block Silo. There are two methods of using con-
crete: (1) in the form of blocks, which are made and cured
before being laid in the wall; (2) the monolithic wall, require-
ing the use of forms. The first method involves a large
amoimt of labor in making and handling the blocks and lay-
ing them in the silo wall. So much labor is involved that
it is likely to be the most expensive item of the entire cost.
The use of forms in the monoUthic construction dispenses
with a large part of the labor, but in turn offers some serious
disadvantages. To obtain good, smooth walls, rather
expensive forms must be made; and as the silo reaches some
height, the forms are difficult to handle without expensive
scaffolding and hoisting apparatus.

Digitized by

Google

FARM STRUCTURE 469

Monolithic Silos. The soUd wall does not ofiFer serious
objections in permitting the freezing of the silage, especially

if provided with a good,

tight roof. The concrete
silo blocks are nearly al-
ways made to contain an
air space, and double forms
may be used in the mon-
oUthic construction, mak-
ing a double wall. When
air circulation is restricted
in the dead-air space by
horizontal partitions about
every three feet of height,
the double wall is perhaps
the most satisfactory, as
far as frost-proof qualities
are concerned.

The cost of a concrete

silo will depend largely

upon local conditions. The ^ig. 295. a ipononthic-siio with con-

^ Crete roof.

cost of sand, gravel, and

labor are the deciding factors. Under usual conditions, the
cost should not greatly exceed the cost of a first-class wood-
en silo. No attempt will be made here to discuss the con-
struction of forms.

The Hollow Clay Block, or Iowa Silo. In general, this
silo consists of a wall of vitrified clay building blocks reinforced
with steel laid in the mortar joints. The roof is made of
concrete, and the silo has a reinforced concrete door frame.

Description of the Blocks. The blocks are hard-burned
building blocks, and may now be had curved to the curvature
of the silo wall, making a smoother wall on the inside. These

Digitized by

Google

470

AGRICULTURAL ENGINEERING

blocks are of the same material and have the same character-
fstics as brick; in fact, in certain localities they are called

hollow brick. If these
blocks are of good mate-
rial and hard-burned they
are very dm-able.

The 4x8xl2-inch block
has proven to be a very
satisfactory size. Larger
blocks are too large to
handle with one hand, and
smaller ones require more
labor in laying. These
blocks are laid on edge,
making a fom*-inch wall.
The Cement Wash. If
curved blocks are used
and care is used in point-
ing and filUng the mortar
joints, the wall will be suf-
ficiently smooth on the in-
side to omit the plastering.
To seal the mortar joints and make the whole impervious,
a cement wash should be applied before the mortar becomes
hardened.

Reinforcement. The . entire bm^ting pressure of the
silage should be carried by steel wire imbedded in the mortar
joints. Number 3 wire has been foimd to be a very satis-
factory size. It is small enough not to interfere with the
laying of the blocks, and fewer strands are required than of
the smaller sizes. This wire should be unanneaJed, and may
be straightened to the curvature of the silo by drawing it
through a piece of pipe bent to the proper angle.

Fig. 296. The Iowa silo made of hollow
vitrified clay building blocks or tile.

Digitized by

Google

FARM STRUCTURES 471

The Doorframe. The doorframe is continuous with the
erossties, which are at least 42 inches apart. The jambs are
simply reinforced concrete beams. The erossties contain
. reinforced bars of equal strength to the horizontal reinforce-
ment in the wall proper, and extend back to each side into
the open space in the
blocks, to obtain a good
grip upon the wall. The
blocks containing the bars
are completely filled with
concrete. The bars across
the doorway are covered
either by blocks filled with
concrete or by concrete
alone.

The FounMtion. The ^,^ ,,,^ ^^^ ^^„ ^, ,^^ i^^^ ^^^^
foundation for the Iowa

silo may be of any good masonry construction. It is im-
portant that the footings be placed below the frost line.
Concrete and hard-burned blocks have been used with equal
success. A 16-inch footing and a 6- to 8-inch wall are all that
is required. The space inside of the wall may be economic-
ally added to the capacity of the silo. The extra expense
involved is simply that of throwing out the earth within
the foundation walls.

Floors. Although a floor is not absolutely necessary,
it adds much to the convenience of removing and cleaning
up the silage at the finish. Four inches of concrete will make
an excellent floor. Paving blocks or sidewalk blocks have
been lised successfully. A few floors have been made by
laying the hollow blocks flat and plastering with cement on
top.

Digitized by

Google

470 AGRICULTURAL ENGINEERING

The Roof. The roof of the Iowa silo is constructed of
concrete, making this part as durable and lasting as the rest
of the silo. The cornice is made of blocks laid fiat-wise,
and the center is made of two and one-half to three inches •
of concrete placed upon a conical form. The conical shape
is very desirable for a concrete roof, as nearly all of the
reinforcement may be confined in the base of the cone. If
thoroughly reinforced at this point, there is little opportunity
for failure. A window must be provided in the roof for
fiUing the silo.

QUBSTIONS

1. Where should the silo be located?

2. What are the factors that determine its diameter and height?

3. How does the capacity of a silo vary with its diameter? How
does the amount <^ material in the walls vary with the diameter?

4. How much silage should be fed from the surface each day?

5. What are the essentials of a good silo?

6. Discuss the construction of the stave silo.

7. Upon what does the durability of the stave silo dep^id?

8. What are the merits of the plain-stave silo?

9. How are silo staves spliced?

10. Discuss the construction of the silo foundaticm.

11. Can a silo pit be used to increase the capacity of a stave silo?

12. Describe how a stave silo should be anchored and guyed.

13. Describe two types of doorways for silos.

14. Describe the construction of the Minneapolis ot panel silo.

15. What is necessary to make a satisfactory silo wall oi concrete?

16. How should the walls be reinforced?

17 What kind of mixture should be used in preparing the concrete?

18. What are the advantages and disadvantages of the cement-
block silo?

19. Describe the monolithic concrete silo.

20. Describe the hollow clay block or Iowa silo.

21. What are the desirable features of clay blocks for silosr

22. How may the wall be made impervious?

23. How can the clay-block silo be carefully reinforced?

24. Describe the construction of the doorframe, the foundation,
the floor, and the roof of the Iowa silo.

Digitized by

Google

CHAPTER LXXIII
THE IMPLEMENT HOUSE AND THE SHOP

The Value of an Implement House. It is not economical
to have the machinery stored in the general bam or in any
expensive building. The implement house or shed need
only provide protection* from the weather. Bams do not
furnish good storage on account of the dust which must
necessarily be about and because of the inconvenience.

The Location. The best location for the implement
house is that which makes it a central feature of the farmstead
group. A location about half-way between the house and
bam and a little to one side of a direct Une between the two
buildings seems to be the most generally desirable. The
implement house in this connection is thought of as provid-
ing storage for the farm wagon and other vehicles used upon
the farm. Its location should be such that it will be con-
venient to hitch to a vehicle or implement upon coming from
the bam with a team and enable the driver to pass as directly
as possible to the field or to town without extra travel.

The Size. The size of the house will depend on the
nmnber of implements to be stored. It is not best, however,
to have the building too wide, as it will be inconvenient to
remove certain implements on accoimt of those stored in
front, which arrangement will be necessary to utilize all of
the space in a wide building. In preparing to build an
implement shed, it would be well to determine the floor
space required for each implement and then plan on having
a certain place reserved for each. This arrangement will
save much time in handling the implements.

473

Digitized by

Google

474 AGRICULTURAL ENGINEERING

The Foundation. The foundation need not be heavy; a
6-inch concrete wall will be ample if it be widened to 8
to 12 inches for the footing. Piers are very satisfactory for a
frame building. If the walls of the house are to be of masonry
construction, the foimdation should extend below the frost
line.

The Floor. A dry earth floor is customary in the imple-
ment house. A wood or concrete floor in the carriage or

Fig. 298. A convenient open-front Implement house.

automobile room would be desirable, but not a necessity.
Concrete is best, as boards or planks are likely to provide a
harbor for rats and other vermin.

The Walls. The walls need only provide protection
from the sim, moisture, and wind. Either drop or matched
siding or plain boards with battens may be used. The plain
boards, as usually erected, make a tighter wall after they have
been in use for a time, and they last longer. Concrete makes
a very good wall for an implement house and is not imduly
expensive if the wall is not made too thick. A four-inch wall
is suflicient if placed upon a good foimdation, and, if the wall
be long, it may be stiffened by an occasional pilaster. In
Uke manner a four-inch brick wall will be found to be quite

Digitized by

Google

FARM STRUCTURES 475

satisfactory. Hollow clay building blocks, when such mate-
rial of good quality can be readily obtained, make a very
desirable wall for the implement house. Blocks are much
cheaper than brick and more wall can be laid in a given time.

One advantage of the masonry walls is that they are more
nearly dust-proof than a single-board wall, and the imple-
ments they protect will present a better appearance at all
times. This feature is of little advantage except in the care
of the buggies or carriages. If a good, tight wall be provided,
it will not be necessary to cover the vehicles with a cloth, as
is practiced by many who take pride in the appearance of
their turnouts.

The Roof. The roof can well be made of an assortment
of materials. Boofing boards with battens make a good,
cheap roof for a narrow building, especially those with the
roof sloping one way only. A shingle roof, of at least one-
third pitch and of a good quality of cedar or cypress shingles,
is quite satisfactory, but is not nearly as dust-proof as some
of the other forms of construction. A layer of building paper
over the sheathing, as commonly used in house construc-
tion, would improve it in this respect. Prepared roofing
makes a very desirable roof for an implement house, as it is
perfectly tight and when a good quaUty is used its durability
will compare favorably with shingles. Care should be
taken to make the walls tight between the roof and the plate,
where it is desired to have a dust-proof building.

The Framework. The framing of an implement house
is not difficult. If a gable roof is used, 2x4 rafters placed
two feet on center will be sufficient for a building 16 feet wide,
if given at least one-third pitch. If the house has a shed roof,
2x4 rafters will be sufficient for a 12-foot span with a one-
third pitch. A wider building should have 2x6 rafters, if the
building is to retain its shape. If the house is to have a sec-

Digitized by

Google

476

AGRICULTURAL ENGINEERING

ond floor, and the joists do not support the plate and prevent
the thrust of the rafters from spreading the building, there
should be several diagonal braces from the plate to the joist.
The implement house may be built with one side open.
This is a convenient arrangement, but does not keep out the
dust; and the chickens of the farm, if not confined, will find
the machinery a very satisfactory roosting place, much to the
detriment of the machinery. If large doors are provided, it
4S'-0'

- . p?^si^9rAffyf.4s9fy^

|=E3«

^Cc^er0/» kxM'

M4'^l4'b09m.

7J9S ei^a/y O'.

UIl

^Jron\bo/tCr'f

Fiff. 299. A cross section of the house shown In Fiff. 298.

will not be inconvenient to store the various machines; in
fact, one entire side may be made up of doors hung on a
double track, half of them being on the outside track and the
other half on the inside track. This arrangement permits of
the doors* being opened at any point.

It is often an advantage to have a second floor, to accom-
modate the Ught implements, such as the cultivator, stalk
cutter, com planter, etc. The implements may be drawn
up on a runway by means of a horse and a rope and pulley.

Digitized by

Google

FARM STRUCTURES 477

THE FARM SHOP

Utility. From an extensive investigation on the life and
care of farm machinery in Colorado, it is reported * that 71.36
per cent of the farm machinery on farms not having shops
needed repairs, while only 59.25 per cent on farms having
shops needed repairs. These facts are taken by the writer of
the bulletin to mean that the farm shop has a "real value
beyond the occasional emergency job."

It is well-nigh impossible to maintain the efficiency of the
farm equipment without a liberally equipped shop. It is
not so much a matter of saving a few dollars by doing repair
jobs, as it is a matter of getting the work done.

The Location. The location of the farm shop should be
similar to that described for the implement house; indeed
it may be made a part of or an addition to the implement
house, as its usefulness is largely directed toward the farm
machinery. If a forge is installed, due thought should be
taken of danger from fire. The location may also be selected
with reference to any small stationary engine or i)ther source
of power the farm may have, so that the same power may
be available for tools in the shop.

The Size. The farm shop may be built large enough to
house a wagon or similar implement, or it may be just large
enough to contain a bench and tools and furnish the minimum
amount of working room. A shop 16 by 20 feet will be
needed to accommodate large machines. On the other hand,
a shop 8 by 10 feet will house a bench, a forge, and an anvil,
and may be considered the minimum size for practical pur-
poses.

Construction. The house should afford comfortable
quarters for work during cold weather. If made wind-

*Bulletin No. 167, Colorado Agricultural Experiment Station.

Digitized by

Google

478 AGRICULTURAL ENGINEERING

proof, a stove may be put in. If a forge be installed; it and
the anvil should be placed on earth, concrete, or some other
kind of iSre-proof floor. The exterior of the shop should be
made to conform to the style of the other buildings about the
place. In buying the equipment, care should be exercised to
get good, standard tools of known merit.

QUESTIONS

1. Why have a separate implement house on the farm?

2. Discuss the best location for an implement house.

3. How may the size of the implement house be determined?

4. Discuss the ccmstruction of the foundation, the floor, the walls
and the Tooi of the implement house.

5. Describe how the frame of an implement house may be con-
structed.

6. To what use may the second floor of an implement house be
put?

7. Why is a repair shop needed on a farm?

8. Where should the farm shop be located?

9. What are satisfactory dimensions for a farm shop?
10. Discuss the construction of a farm shop.

LIST OF REFERENCES FOR FARM STRUCTURES

Building Trades ELandbook.
Farm Buildings.

Radford's Practical Bam Plans.
Bam Plans and Outbuildings.
The Farmstead, I. P. Roberts.
Tuthill's Architectural Drawing.
Architectural Drawing, C. F. Edminster.

Practical Suggestions for Farm Buildings, U. S. Dept. of Agri.,
Farmers' Bui. 126.

College Farm Buildings, Mich. Agri. Exp. Sta., Bui. 250.
Circular No. 15, Division of Forestry, U. S. Dept. of Agri.
Architects' and Builders' Pocket Book, F. E. Kidder.
Mechanics of Materials, Church.
Materials of Constmction, J. B. Johnson.

Digitized by

Google

FARM STRUCTURES 479

Farm Poultry House, Bui. 132, Iowa Agr. Exp. Sta.

Building Poultry Houses, Cornell Bui. 274.

Poultry House Construction and Yarding, Mich. Bui. 266.

Poultry House Construction, Wisconsin Bui. 215.

Poultry Architecture, George B. Fisk.

Location and Construction <^ Hog Houses, 111. Agr. Exp. Sta., Bui.
109.

Hog Houses, U. S. Dept. of Agr., Farmers' Bui. 438.

Portable Hog Houses, Wis. Agr. Exp. Sta., Bui. 153.

Suggestions for the Improvement of Dairy Bams, 111. Agr. Exp.
Sta., Cir. 95.

Economy of the Round Dairy Bam, HI. Agr. Exp. Sta., Bui. 143.

Sanitary Cow Stalls, Wis. Agr. Exp. Sta., Bui. 185.

Plank Frame Bam Constmction, John L. Shawver.

Hodgson's Low Cost American Homes.

Modem Silo Constmction, la. Agr. Exp. Sta., Bui. 100.

The Iowa Silo, la. Agr. Exp. Sta., Bui. 117.

Concrete Silos, Universal Portland Cement Co.

Specifications, International Correspondence School Text.

Vaitilation, F. H. King.

King System of Ventilation, Wis. Agr. Exp. Sta., Bui. 164.

Digitized by

Google

PART EIGHT— FARM SANITATION

CHAPTER LXXIV
THE FARM WATER SUPPLY

The subject of farm water supply easily divides itself into
the following heads, each of which will be discussed in turn:

1. .The source of supply.

2. The quantity required.

3. The pumping plant.

4. Th6 distribution system.

5. The storage tank or reservoirs.

The Source of Water Supply. The first requisite of a
suitable source of water supply is that it shall furnish pure
water. It is fully realized at the present time that one of the
most important places where the health of the family is to
be guarded is the water supply, for so many diseases are
traceable to polluted water. It is not so essential that water
be pure chemically as that it be free from all germs which
may cause trouble in the human system. Water may con-
tain a considerable percentage of certain mineral salts and yet
be quite healthful. On the other hand, water may be quite
free from all salts or mineral matter, be clear, cool, and spark-
Ung, and still be filled with deadly typhoid or other disease
germs.

Wells. The well is the most common source of water
supply for the farm. Wells are divided primarily into two
classes, with reference to their depth, as shallow and deep
wells. The shallow well refers to those either dug by hand

480

Digitized by

Google

FARM SANITATION 481

or bored with a common well auger. These wells are usually
Oi considerable diameter in order that there may be a reser-
voir for a quantity of water within the well itself. The shallow
well is the one most easily contaminated and is the one which
should be most carefully protected. It is best that the well .
be located at some distance from any leaching cesspool,
privy, or manure heaps. It is difficult to state just how far
away, as some soils are much more open than others and the
impurities will travel a correspondingly greater distance

Fig. 300. A sketch showing hew the water of a shallow well may be-
come contaminated from manure yards and cesspools. (Kansas Exp. Sta.
Bui. 143.)

through them. Then, again, drainage lines become quite
thoroughly estabUshed in the soil in certain directions; and
if the well and a source of contamination should happen to be
placed in one of these seepage lines, the contamination would
take place at a much greater distance than otherwise. It is
best, however, that the well, especially a surface well, be
located at least 100 feet from any disease-laden filth.

Much can be accomplished in providing protection against
contamination from the surface: (1) The curb or well wall

16 —

Digitized by

Google

482 AGRICULTURAL ENGINEERING

should be made water-tight for some distance below the sur-
face; (2) the well should have a good, tight platform or cover;
and (3) the surface of the ground should be raised about the
well so that all surface drainage will be away from the well.

Surface wells are the cheapest of all wells. The cost per
foot, with curb, varies from 50c for a 12-inch hole, to
over $2 for a well four feet across and walled with loose
stone. A good platform cemented over will cost about $10.
It might be mentioned here that concrete makes an ideal
pump platform and will last indefinitely. One slab can be
made loose to furnish access to the well.

Deep loeUs are usually either driven or drilled. A driven
well is made by attaching a sand point to a casing, usually IJ^
inches in diameter, and simply driving it into the ground
until the point reaches a water-bearing stratum of gravel or
sand. The sand point is made of perforated brass over an
iron frame, through which the water will readily pass into the
casing. The pump cylinder is made a part of the casing, and
valves are set at proper places by expanding rubber rings to fit
the casing. Driven wells never extend through a rock stratum.
! Drilled wells are made by operating a drill inside a casing
which sinks as the drill provides the way. The mud and chips
of stone are removed by pumping a stream of water through
the drill and out through the casing. If the casing is of small
diameter, about two inches, with the cylinder a part of it, it
is called a tubular well. The usual diameters for drilled
wells are 6 and 8 inches. These diameters permit the pump
cylinder and piping to be entirely independent of the well
casing. The usual cost of tubular wells, with casing, is $1
to $1.50 per foot. Drilled wells range in cost up to $6 per
foot for an 8-inch well drilled in granite rock.

Deep wells are rightly considered a better source of water
supply than shallow wells, yet they are by no means entirely

Digitized by

Google

FARM SANITATION 483

free from contamination. Occasionally drainage lines are
so thoroughly established in the soil and through fissures in
the rock that the water of the deep wells may be contami-
nated from the surface.

Springs are sometimes used as a source of water supply.
It is best that the spring discharge at as high an elevation
as possible in order that there may not be many habitations
above it. When springs furnish water from some depth, the

Pigr. 301. An improved spring showingr how it may be protected from
surface water.

water is quite sure to be free from all organic matter. In
considering a spring as a source of water supply, it should be
definitely known that a sufficient amount of water will be
furnished throughout the year. Most springs are irregular
in their discharge and at times furnish little or no water.

The ideal location for a spring is at an elevation above the
farmstead, to which the water may be led in pipes and perhaps
allowed to flow constantly, the surplus heing wasted. If the
spring is below the farmstead, yet high enough to permit a

Digitized by

Google

484 AGRICULTURAL ENOINEERING

waste to still lower levels, and if the flow is ample a hydraulic
ram or pimiping plant can be used.

Brooks or running streams form another source of water
supply, but should be carefully considered before using? A
close inspection should be made to determine whether or not
the stream is in any danger of pollution by surface washing
from manured fields or house and farm yards. River water
is quite likely to be turbid during the flood season. Streams
flowing through uninhabited or uncultivated upland will fur-
nish water of the most desirable character.

Lakes usually fiunish water that is clear and potable, ow-
ing to the fact that the water is purified by coming to rest and
allowing the impurities to settle. Often, in settled commu-
iiities, where the practice is not forbidden by law, the banks
of lakes are used as a dumping ground for all sorts of
refuse. Such practice prevents the use of the water for
human consumption.

Drinking water obtained from a stream or lake should be
filtered. A box filled with sand and gravel or charcoal
through which the water must pass is the most common type
of filter in use.

The Quantity Required. Care must be taken, in selecting
a water supply, to determine that the quantity of water
available will be sufficient not only for all present needs but
also for any increased demand that may be foreseen. The
daily requirements must also be taken into account when
planning a reservoir or storage tank.

The greater part of the water consumed on the farm is
required by the live stock for drinking purposes and by the
household. The house requirements depend largely on
whether or not plumbing fixtures are installed. The amount
consumed per day by each of the various farm animals is
about as follows: A horse, 7 gallons; a cow, 6 gallons; a

Digitized by

Google

FARM SANITATION 485

hog, 3 gallons; and a sheep, less than 3 gallons. Dairy cows
giving milk require additional water in proportion to the
amount of milk given. Where sanitary plumbing is installed,
about 20 gallons of water per day will be consimied for each
person, large or small, and for all purposes, including the
laundry.

QUESTIONS

1. Into what divisions or heads may the subject of fann water
supply be divided?

2. What are the principal sources of water supply on the farm?

3. Explain how surface and deep wells are dug or drilled and curbed
or cased.

4. Describe how the well should be protected from contamination.

5. When may springs, running water, and lakes be used as a source
of water supply?

6. How may the daily consumption of water be estimated?

7. Estimate the amount of water required on the home farm.

Digitized by

Google

CHAPTER LXXV
THE PUMPING PLANT

The pumping plant for a farm water supply consists of
some form of motor and a pump. Although many pumps are
still operated by hand, a modem water system can scarcely
be considered complete without a motor, for the simple reason
that man cannot comp)ete with motors in the production of
power. A specific instance is on record where a gasoline
engine pumped the water for a dairy herd at a cost of one cent
per day for gasoline; whereas two hours of hand labor, worth
at least 20 cents per hour, were formerly required. It is a
waste of money to pump by hand if a large quantity of water
is required daily. The forms of motors now in use for pump-
ing purposes are the windmill, the gasoline engine, and, in a
few instances, the hot-air engine and the water wheel.

Sources of Power. A mndmiU is better siiited by far
fbr the pumping of water than for any other purpose. The
power of a windmill is quite limited; yet an average pump
requires Uttle power. Furthermore, the power is quite irreg-
ular, but if a storage reservoir is used this undesirable feature
is easily overcome. As discussed in a previous lesson, the
cost of windmill power consists of the interest on the invest-
ment, and the depreciation and maintenance.

The gasoline engine is well adapted to the pumping of
water. As has been stated, the average pump requires very
Uttle power, and the gasoline engine has the advantage over
other heat motors in that it is very economical in small units.
A series of tests made a few years ago at the Iowa State Col-
lege indicated that 20 barrels of water could be pumped

486

Digitized by

Google

FARM SANITATION 487

agidnst a head of 100 feet, or, in other words, lifted that dis-
tance, for every day in the year, at a cost of less than
five dollars for gasoline. Again,
the gasoUne engine does not need
constant attention. K anything
goes wrong, the engine will Ukely
stop without doing damage. A
float or other safety device may
be connected with the igniting
system or fuel supply in such a
way as to stop the engine when a '
certain height of water in the
supply tank or a certain pressure
has been attained.

Hoiroir engines have little to
commend them oth^r than their
reUabiUty and safety. Solid fuel
of almost any kind, as well as oil
and gas, may be used. They are
not economical of fuel, but where
the fuel is cheap theymay be oper-
ated at a reasonable expense.

Waierwheds can be used only in
rare instances, and will not be dis-
cussed for this reason. There are,
no doubt, many places ivhere they
may be used to advantage. ,^lf.^lf- tr '"u'nVrSUl

Tlie pump is as important a ^T a ''hVSrLTc'' iXd^t^
part of the pumping plant as the JlJS.rwhen a'iertal" v^^l
motor. Pump troubles and repairs ^^^ **®®° reached.
are alwajrs very annoying, and a pump of good construction
and properly installed is always a good investment. The
amount of power required to operate a pump is small, as will
be shown by the following table:

Digitized by

Google

48S

AGRICULTURAL ENGINEERING
Pump tesU,

No.
teftt

Kind of cylinder

Lift

Gals, per

H. p.
used

Hydntu-
Uc H. P.

Effi.
eienoy

percent

2^', brass lined

5.81

.195

.0732

57.0

2J4', brass lined

100

5.33

.255

.1343

52.5

3', brass body

8.01

.21

.1019

48.4

3', brass body

100

7.8

.395

.1965

49.6

4', plain iron

10.0

.52

.126

21.2

4', plain iron

100

10.3

.75

.259

34.7

Important Features of a Pun^i. In selecting apump, the
service to be required of it should always be kept in mind. If
the water is only to be lifted from a shallow well and delivered
into a pail or tank mider the spout, any common lift pump
may be used. A Uft pump is one in which no provision is
made for forcing or lifting the water lygher than the pump
spout. Force pumps have the pump rod packed, making it
water-tight.

One of the most important parts of a pump is the cylinder,
of which there are three common grades on the market; viz.,
plain iron, iron with brass Uning, and brass-body cylinders.
The first is the cheapest, but is the least durable, as iron
easily corrodes. Brass-lined cylinders are quite satisfactory,
in that the iron supports and protects the brass, which is a
soft metal. Brass-body cylinders are used where corrosion
will be imusually rapid and where space is Umited. Often, in
drilled wells of small diameter, brass-body cyUnders with the
caps screwed inside of the barrel instead of on the outside
are installed, thus permitting the use of a cyUnder of rela-
tively large diameter. Brass-body cyUnders will not stand
severe service. When dented, they are almost past repair,
and the screwing of the caps to the thin barrel is difficult, be-
cause little material is provided for the threads. Porcelain-

Digitized by

Google

FARM SANITATION 489

lined cylinders are used where the water contains elements
that corrode iron and brass.

Plungers are constructed to suit the Uft under which they
are to work. If the lift has but a few feet, one plunger
leather which expands out toward the cylinder walls, making
a water-tight fit, will be sufficient; but if the well is deep or
the water is to be lifted against pressure, as many as four
leathers will be found best.

Fig. 303. Some common types of pump cylinders. 1 is of plain cast
iron, 2 is galvanized, 3 is porcelain lined, 4 and 5 are brass lined, and
6 is an all-brass cylinder.

The valves are another important part of a pump.
They should be designed to resist wear and to require the
minimum of attention. There are at least four types of
valves used in farm pumps. The hinge valve, made with a
metal weight on a leather disk and attached at one side, is
used where the lift is not great. It is a simple valve and the
cheapest, but is not well suited for high pressures. Poppet
valves are those which Uft directly from the seat, and are
made with one or three prongs to guide the valve to its seat.
These valves are the easiest to repair. Ball valves are used

Digitized by

Google

490 AGRICULTURAL ENGINEERING

where the water is likely to contain sand, as the seat of the
ball valve is usually quite narrow and the sand is not given
an opportunity to lodge upon it.

The Stock. The part of the pump visible above the plat-
form is known as the stock, and is made in a variety of styles.
The simplest form is the lift pump, which, as a hand pump,
was formerly made with wooden stocks, but now cast-iron is
generally used. The next simplest is the force pump, made
after the plan of the common Uf t pump, with provision to pre-
vent leakage about the pump rod.

Where the water is to be pumped into a storage tank and
the pump is in a more or less exposed location, a three-way
pump may be used. It provides a valve that enables the
water to be pumped out of the spout, or delivered through an
underground pipe to the storage tank, or drawn from the tank
through the spout.

In cold climates a pump should be protected against freez-
ing by surrounding the valves with a frost-proof well pit and
providing for the drainage of the pump stock. If a com-
pressed air system of water storage is installed, a special
pump must be provided which will pump a little air with the
water; or a separate air pump must be used.

QUESTIONS

1. Is the pumping of water by hand ever economical?

2. What are the principal sources of power for pumping water?

3. Discuss the relative merits of the gasoline engine, the windmill,
and the hot-air engine, for pumping water.

4. Describe the difference between a lift pump and a force pump.

5. What are the relative merits of the different kinds of pump
cylinders? Pump valves?

6. Describe the three-way pump and its use.

7. How should a pump be protected from freezing?

Digitized by

Google

CHAPTER LXXVI
DISTRIBUTING AND STORING WATER

Water Pipe. After a consideration of the source of sup-
ply for a farm water system, the quantity of water required,
and the pumping plant, the next thing to be considered is the
distributing system or piping by which the water is conveyed
to points where needed and to the reservoir for storage. For
farm water systems, wrought-iron or steel pipe with screwed
joints is universally used. Cast-iron pipe with leaded joints
is used for pipes four inches or larger in diameter, but pipes
this large are seldom required in connection with farm sys-
tems. Wrought-iron or steel pipes placed imderground
should always be galvanized or coated with asphalt to pro-
tect them from rust. They are commonly galvanized.

Sizes of Pipe. The two sizes of pipe in general use are
three-fourths and one inch. In rare instances half-inch pipe
may be used, but the flow of water through this size pipe is
very slow, especially if a long length is used. The friction.
betweA the water and the walls of the pipe coimteracts the
pressure which causes the water to flow. The folfcwing
table, taken from the Cyclopedia of American Agriculture,
indicates how great the friction is with small pipe. ? «€t ;^iki

deferring to the table it is seen that if a pump is deliv-
ering four gallons per minute through a length of J/^-inch pipe
500 feet long, it must do so agaiiist a friction head or pressure
of 270 feet of water. This woiild be impractical. Although
the table does not include J^-inch pipe, the loss of pressure
due to friction would lie between the values given for 3^- and
1-inch pipe. The average farm pump will discharge about

491

Digitized by

Google

492

AGRICULTURAL ENGINEERING

5 gallons per minute, which would require the use of pipe at
least 1 inch in diameter or larger for mains, and the smaller
sizes should only be used for branches. In many cases the
pump is overloaded by using pipe of insufficient size.

Flow of water in pipes.

Flow in gallons per minute

Head in feet lost by friction in each 100 foot of length

H-inch pipe.

1-inch pipe.

0.5
1.0
2.0
4.0
10.0

224

.03
.07

1.6

5.3

9.3

Piping Systems. There are two general types of under-
ground piping systems on farms. The first of these is known
as the "ramified " system, which consists of a main laid in the
shortest possible Une from the water supply to the farthest
hydrant, with branches extending out on either side like
branches of a tree. The one objection to this arrangement
is that the water in the branches is dead unless constantly in
use. There is, however, a saving in the cost of pipe, as
smaller sizes may be used for the branches. The second type
is known as the " circulatory " system, in which the main pipe
passes to all hydrants and the extreme ends are connected, if
possible. With this system the water does not stagnate in
any part.

In planning the distributing system, it is best to provide
large mains if fire protection is desired. Valves should be
put in various parts so that a disturbance in one part will not
interfere with the use of the rest of the system. Often it
can be arranged to have the fresh water, as pumped, pass
through the house, thus providing drinking water.

Digitized by

Google

FARM SANITATION m

Water Storage. The size of the storage tank and reser-
voir will depend primarily on the kind of power used for
pumping. It is customary to provide in storage a supply to
last five days when the pumping is done by a windmill; and
when a gasoline engine is used, the storage capacity may be
reduced to a two-days' supply.

The two general methods
of storing water are by the use
of the elevated tank and the
pressure tank. The first of
these depends upon gravity to
force the flow of water, and the
second uses compressed air.

Towers and Tanks. The
ideal location for an elevated
water reservoir is upon some
natural eminence. If the emi-
nence is high enough to justify
it, the reservoir may be built
beneath the surface like a cis-
tern, thus insuring that the
water will be kept cool. If
there is no natural means of

securing elevation, the tank fi^. 304. An lowa siio with a
must be placed upon a tower Zr''"'' ""'"' ''"'*'*'^ '""^ '"
or in a building. The height

of the tower will depend upon the height of the buildings to
which the water is to be delivered and upon the pressure
desired. The tower may be made of steel, wood, or masonry.
Masonry tanks are best, but often the cost is prohibitive.

A tank on a tower is exposed more or less to the weather
and will give trouble from freezing. This is especially true of
steel tanks. Wooden tanks are preferred over steel for out-

Digitized by

Google

494

AGRICULTURAL ENGINEERING

side locations, as they are easier to erect and are cheaper.
Cypress is considered one of the best woods for tank construc-
tion, and may be expected to last 15 to 20 years.

Tanks are sometimes placed in or on buildings, but great
care should be taken to determine whether or not the building
is suflSciently strong for the purpose. Water in quantity is
very heavy: 300 gallons will weigh 2,500 pounds, to which
must be added the weight of the tank. Tanks placed in
residences have often caused settling of the framework under-
neath and consequent cracking of the plastering. In bams
they can be supported to better advantage.

Cement or concrete towers and tanks are coming into use
and, when properly built and reinforced, there is no reason
why they should not be economical.

The masonry silo provides what is seemingly a good loca-
tion for a water tank for a farm water supply. The tanks
themselves may be built of masonry if properly reinforced,
jind plastered with cement plaster on the inside. The bottom
, /9f the tank can be easily constructed of concrete, if built in a
conical form and reinforced to prevent cracking at the base.

The Air-Pressure System. The pressure tank, or pneu-
matic system, consists of an air-tight tank, a force pump.

<Miijiuill,iiiii.;iH5W!iirji«!i|

f>'c

>^^■■•.

/'-.V-

^ :

^m'

..'.• '

Fiff. 305. An air pressure or pneumatic water supply system.

Digitized by

Google

FARM SANITATION 495

and suitable piping. As water is forced in at the bottom of
this tank, the air within is compressed, thus driving the
water from the tank to any part of the system. As the
efifective capacity of the tank may be increased by having
an initial pressure of air within it, and as the water con-
tinually absorbs a part of the air, an air pump or a pump
to supply the air with the water must be provided.

As the water is thoroughly protected by being tightly
inclosed, the tank may be placed where a freezing tempera-
ture is not reached. The cellar is the usual location. It
may, however, be bmied in the ground, which has the advan-
tage that the water is kept at quite a uniform temperature
throughout the entire year.

The air pressure tank for a water supply of small capacity
is very economical in first cost. Where the storage capacity is
large, however, the cost is so great as to be almost prohibitive.
A ten-barrel tank with a
water storage capacity of
six barrels will cost about
$60, and larger tanks a
correspondingly greater
amount.

A more recent water-
supply system is known
as the Perry pneumatic
water-supply system. It
consists in a power-driven
air compressor, a storage
tank for the air imder

pressure, and an air- Flgr. SOe. a satisfactory method of Install-
j . , I.' u ^^S exposed hydrants.

driven water pump which

pmnps the water as required, maintaining a pressure upon

the entire system. There is no storage of the water at all,

Digitized by

Google

496 AGRICULTURAL ENGINEERING

other than that contained in the pipes. Definite information
is not at hand concerning the cost or the success of this system .
One distinct advantage of it is that water may be pumped from
as many supplies as there are pumps. Thus one pump may
supply well water for drinking purposes, and another cistern
water for the bath and laundry.

QUESTIONS

1. What kind oi pipe may be used in the distributicm system, and
what are the merits of each?

2. What arc the sizes of pipe generally used for the farm water-
supply system?

3. Explain how the loss of friction may be serious with small pipes.

4. Describe the ramified and circulatory systems of water piping.

5. What provision may be made for fire protection, for repair, and
"or cool drinking water in the water supply system?

6. In what way does the amount of water storage vary with the
source of power?

7. Describe the two general systems of storing water.

8. Discuss the construction of elevated water supply tanks.

9. What are the objections to an exposed water supply tank?

10. What care should be taken when the supply tank is placed in
a building?

11. Why does a masonry silo make a good tower for a water supply
tank?

12. Describe the air pressure or pneumatic system of water supply.

13. What are the advantages of this system and the main objection
to it?

14. Describe the Perry system.

15. What is the principal advantage of this system?

Digitized by

Google

CHAPTER LXXVII
PLUMBING FOR THE COUNTRY HOUSE

Modem conveniences for the country home are usually
understood to include sanitary plumbing fixtures for the
bathroom and for caring for the wastes of the household.
The use of such fixtures is dependent upon an adequate water
supply, a subject which has been discussed in the preceding
chapters. There is nothing which will do as much toward
reUeving the housewife of hard and disagreeable labor as the
plumbing. It not only provides additional comfort and con-
venience to the extent that when once used it is considered
indispensable, but it also guards the health of all members
of the household.

Opinions differ widely in regard to the details of construc-
tion and design of sanitary plumbing. In all cases care must
be used that unnecessary expense is not incmTed in securing
something which does not represent quaUty. As a rule the
most simple fixtures are the most satisfactory. All parts of
the fixtures, such as traps and overflows, should be so placed
as to permit of ready inspection.

Plumbing Fixtures. In installing plumbing fixtures, con-
soUdation should be kept in mind. The usual fixtures
installed in a coimtry home are a sink and hot water appli-
ances in the kitchen, and a bathtub, closet and lavatory in the
bathroom. If the bathroom can be placed above or adjoin-
ing the kitchen the installation of the fixtures will be much
simplified and much piping saved. The nmnber of fixtures
which may be installed will depend largely upon whether or
not the house is to have furnace heat. If the house is to be

497

Digitized by

Google

498

AGRICULTURAL ENGINEERING

t/*rtfil0tiof*

t^m*»reto—f^

heated with stoves, the bathroom can best be arranged to
adjoin the kitchen, and the heat therefrom ought to prevent
the freezing of the water in the pipes. For this reason the

pipes should be protected
as far as possible from the
cold. It is not best, how-
ever, to place them in the
wall, as exposed pipes are
decidedly more convenient
to repair. One very satis-
factory method of caring
for the pipes is to provide
a conduit with a removable
cover, which may be panel-
ed in such a way as not to
detract from the appear-
ance of the room. All of
the fixtures requiring
drainage should be clus-
tered about the soil pipe
which should extend from
the cellar up through the
building and out through
the roof for ventilation.
This soil pipe is univer-
sally made of four-inch
cast-iron pipe with fittings
inserted at proper places
to receive the drainage
from the various fixtures.
It is best that a clean-out plug be provided at the bottom.
At a sUght additional cost, hot water may be provided.
All that is required in addition is a hot water or range tank

Figr. 807. A plumbingr system for a
two-story house. The vent pipe may be
omitted with safety In country resi-
dences. (Mo. Ens. Exp. Sta. Bui.)

Digitized byVjOOQlC

FARM SANITATION 499

and a water front for the kitchen range or furnace, and the
necessary piping. The range tank is galvanized and usually
holds from 30 to 60 gallons.

The kitchen sink is one of the fixtures which is well-nigh
indispensable. The cast-iron sink, porcelain lined and with
a roll rim and a back piece, is the most convenient for clean-
ing.^ The porcelain-lined sink is just as serviceable, if not
more so, than the solid porcelain, and is much cheaper. It is
very difficult to keep a plain iron sink clean, and the advan-
tages of the porcelain-lined will justify its purchase.

A very satisfactory size for a kitchen sink is 22 by 36
inches, and it should not be smaller than 20 by 30 inches.
Though opinions differ, 32 inches is an average satisfactory
height. One side may be conveniently arranged to receive
the dishes as they are washed, permitting them to drain.

Bathroom Fixtures. The bathroom ordinarily contains
three fixtures; namely, a bathtub, a lavatory, and a water
closet. Of recent years these fixtures have been greatly im-
proved and cheapened in cost imtil a good grade is within the
reach of all. A serviceable bathtub is one of cast-iron, porce-
lain lined but with a wide roll at the top. like the kitchen
sink it should not have any woodwork connected with it.
The best tubs have all of the piping, including the drains and
overflow, exposed. The standard width for bathtubs is 30
inches, and they may be had in any length from 4 to 6 feet.

The lavatory should be either solid porcelainorporcelain-
enameled cast-iron. To avoid cracks in which dirt may
accumulate, the back should be made sohd with the bowl.

The water closet in general use is of sohd white earthen-
ware with siphon action. The cleaning jet should discharge
from the rim of the closet and should clean thoroughly. Two
kinds of flush tanks are in general use, the ''low down" and
the ''high." The first does not make as much noise when

Digitized by

Google

500 AGRICULTURAL ENGINEERING

flushed as the second but generally uses more water. The
water is discharged from the second with considerable force,
and for that reason is preferred by some.

Back Vents. In nearly all cities all fixtures are required
by law to have vents from the traps to prevent the water
which closes the pipe and prevents the entrance of foul gases
into the room from being siphoned over into the sewer. This
system of piping is shown in the accompanying figure; it intro-
duces considerable extra expense. In country houses there
is doubtless little danger in omitting this extra piping.

There will be Uttle diflSculty in installing plumbing in a
house not built especially for the purpose, providing there is
room for it. There is some inconvenience in putting the
pipes in place, but in most cases they can be left in exposed
locations, which is some advantage.

The plmnbing referred to and of the quaUty suggested
will cost less than $200 almost anywhere in the Middle West;
in fact, the average cost should not exceed $150.

QUESTIONS

1. What are some of the general considerations involved in the
installation of plumbing?

2. How may plumbing be arranged in houses without furnace heat?

3. How secure convenience in cleaning and inspection?

4. What are the usual fixtures required?

5. Discuss the merits of various grades of sinks.

6. What should be avoided in the selection of a lavatory?

7. Discuss the different types of water closets.

8. What is meant by back venting?

9. How much should the plmnbing in an average farmhouse cost?

Digitized by

Google

CHAPTER LXXVIII
THE SEPTIC TANK FOR FARM SEWAGE DISPOSAL

Modem plumbing fixtures for the farmhouse introduce a
new problem, the disposal of the sewage. Present-day ideas
concerning sanitation have made the privy and the cesspool
less tolerable than formerly. The modem sewage disposal
plant, if it is to fill its purpose to the greatest extent, should
not only prevent accmnulation of sewage to harbor disease
and contaminate the water supply, but should also provide
for the saving of fertiUzing material which otherwise would
be wasted.

Disposal of Sewage into Rivers. If a large stream of
water be near, the sewage may be discharged into it in a
manner similar to that followed by the large cities. The
organic material contained in the sewage when exposed to
the light and air as it passes ofif down the river is rapidly
purified by bacterial action. Rivers as a means of disposing
of the sewage from farmhouses are rarely available and will
not be discussed further.

The Cesspool. While the cesspool has been the most
common method of disposing of sewage in isolated places, it
has but few features to commend it and should not be used if
there is the least danger of its spreading disease. As usually
constructed the cesspool consists of a cistern in the ground,
with an open wall, usually of brick, through which seepage
takes place. In some open soils this seepage is rapid, and no
difficulty is experienced from the cesspool's overflowing at
times. In dense, retentive soils, the soUd matter of the sew-
age closes the porous walls to the extent that the liquids do

601

Digitized by

Google

502 AGRICULTURAL ENGINEERING

not sweep away fast enough. If there is much grease in the
sewage it is Ukely to become hardened over the surface of the
walls, makmg them water-tight. To overcome this difficulty
common lye has been used to cut the grease, with good success.
All cesspools should be arranged with a manhole, which will
permit the settlings or solid matter which collects in the
bottom to be removed at regular intervals, perhaps once
a year.

Many cesspools that have been in use for years are entirely
satisfactory as far as observations go. The success of these
is undoubtedly due to the purifying bacterial action which
the sewage imdergoes in the tank. At best, however, the
cesspool is a dangerous means of disposing of sewage, and
new installations should be of more improved design. Often
the contamination of the water supply is effected at an un-
dreamed-of distance, resulting in typhoid fever, dysentery,
and other complaints.

Principles of Sewage Disposal. The principle involved
in the purification of sewage in the modem disposal plant,
regardless of whether it be for city or private use, is largely
that of destroying the suspended matter in the water by
bacterial action. Outside of this, some results are brought
about by settling, thus caring for a part of thfe suspended
material.

When the sewage from a farmhouse, consisting of the wash
water from kitchen and dairy and the discharge from plumb-
ing fixtures, is draiii^d into a dark reservoir and not disturbed
for a time, rapid bacterial action takes place. The bacteria
which work in a tank of this sort do not need light or air to
live. The action is simply this: the bacteria feed upon the
organic matter of the sewage and thereby partially destroy it;
in addition, a part of this solid matter, or sludge, as it is called,
is liquified.

Digitized by

Google

FARM SANITATION 503

The reservoir provided for this purification by bacterial
action is known as the septic tank. To secure the best
results, this septic tank should be designed to exclude Ught
and air and to bring the sewage to rest and hold it so for a
time.

The purification of ^the sewage, however, is not completed
in the septic tank. To complete the process, means must
be provided to permit another class of bacteria to ^ct upon

Fig. 308. A greneral view of a septic tank arranged to be connected with
an underground irrigation or filter system without a siphon.
(After Stewart.)

the sewage. These must have air and light or they cannot
live. To supply the proper conditions for this second bac-
terial action, two plans are followed: the first is to provide a
filter bed of coarse material, usually gravel, over which the
sewage from the septic tank is discharged at intervals; and
the second is to provide a shallow tile system fr9m which per-
colation will take place. These tile are usually placed within
ten to twelve inches of the surface, and, if the soil is retentive,
a second and deeper system is laid to carry away the purified
sewage. In some places this filter system of drain tile is used

Digitized by

Google

604

AGRICULTURAL ENGINEERING

as a means of subirrigation, furnishing the growing plants on
the surface with moisture and fertility. It is to be noted that
the discharge into the filter system should be intermittent, in
order that the bacteria at work shall not be drowned.

Another plan of filtering which is used to some extent is
to allow the discharge to trickle down Jhrough a bed of sand,
which is placed over a perforated cover, to a second tank in
which the water level is maintained several inches below.
The dripping of the sewage through the air corresponds quite

Fig. 309. Section of a septic tank made entirely of concrete. It has
a siphon and a Alter bed of sand and gravel.

closely to the sprinkling system of sewage disposal which is
used to some extent in city plants.

Size of Septic Tank. The septic tank should be suffi-
ciently large to hold the entire discharge for about one day,
in which case the hesi bacterial action will be obtained.
Another rule tried out more or less by practice is to provide 20
gallons' capacity for each personin the household. There will
be a settlement amounting to several pailfuls in the. septic
tank each year, and provision must be made for its removal.

Construction of the Septic Tank. Concrete is the best
material for the septic tank. The tile line to the tank from
the house should be of vitrified bell-mouthed tile with
cemented joints.

Digitized by

Google

FARM SANITATION

505

Fig. 310. A plan of a tile system foi
I — : — xi-_ discharge from a septic

filtering
tank.

the

Rg. 308 is a general view of a septic tank which has been
built for as Uttle as $18.65. It has a plank top, and the only
means of cleaning it out would be to uncover the earth and
remove the planks. Fig.
309 is a more expensive
plant, with a filter bed
attached. The filter bed
complete will cost by it-
self about $20. The best
results can be secured
with a tank provided with
a siphon. Fig. 310 shows
a plan for laying the tile
system to filter the discharge from the septic tank.

It is remarkable how thoroughly sewage can be purified by
an efficient plant. Often the effluent or final discharge from
the filter bed will compare in purity with the best well water.

QUESTIONS

1. How is sewage purified that is discharged into a river?

2. What are the objections to a cesspool as a means of disposing
of sewage?

3. Discus? the construction of the cesspool.

4. How is sewage purified in a septic tank?

5. How can complete purification of the sewage be obtained?

6. Why is it best to have the sewage applied intermittently to the
filter bed or irrigation tile?

7. Discuss the construction of the septic tank.

8. Estimate the cost of a sewage disposal plant for a household of
ten people.

Digitized by

Google

CHAPTER LXXIX
THE NATURAL LIGHTING OF FARM BUILDINGS

Development. If a comparison be made between the
fann buildings of twenty-five years ago and those which are
entitled to be called modem, it would be foimd that one of the
principal differences lies in the natural lighting, or the amount
of window surface provided. This change is due largely to a
more general recognition of the value of light as a sanitary
agent.

Purpose of Natural Lighting. The natural lighting of
farm buildings has a three-fold purpose: (1) The principal
purpose, to make the buildings more sanitary by destrojdng
disease germs; (2) to provide a more convenient and pleasant
place for the attendants to care for the animals; and (3) to
provide more pleasant and comfortable quarters for the
animals to feed and live in. As stated, the principal reason
for providing adequate natural Ught for farm buildings is to
secure sanitary quarters for the animals. Direct sunlight is
far more powerful and destructive to disease germs than
diffused or reflected light, and for this reason as much direct
sunlight as possible should be provided. Usually but a short
time, a few hours, is required to kill germs by direct sunlight.

In regard to the value of diffuse light for destroying
germs. Dr. Weinzirl, an eminent bacteriologist, is quoted in
King's book on Ventilation as follows: "The shortest time
in which diffuse light in a room killed the bacillus of tuber-
culosis was less than a day, and the longest time was less than
a week; generally, three or four days of exposure killed the or-
ganisms. Some pus-producing bacteria required a week's

506

Digitized by

Google

FARM SANITATION

507

time to kill them, while some intestinal bacteria were killed
in a few hours. It was also fomid that bacteria are killed
more quickly in moist air than in dry, contrary to general
belief. The diffuse light as found in our dwellings is, there-
fore, a hygienic factor of great importance, and where direct
sunhght is not available it should be carefully provided for."
It is believed that the above quotation represents a clear,
authoritative statement of the value of diffuse sunhght in
producing sanitary quarters.

Location of Windows. In locating the windows, great
care should be taken that sun-
light will be admitted in such
a way as to allow the direct
beams of Ught to sweep the
entire floor. The angle of
incidence of the sun's rays, or
the distance of the s\m above
the horizon, for latitude 42°
north varies from 70° the 22nd
of June to 26° the 21st of Dec-
ember. For other latitudes
the angle of incidence is
different. At the spring and
fall equinoxes, which take
place March 21 and Sept-
ember 21, and for 42° N. the
angle is 48°. Sunlight is more
useful in the winter time than
in the summer, and care
should be taken to make use of the winter sun rather than the
summer sun. For practical purposes it can be assumed that
the most desirable sunhght enters the windows at an angle
of 45°.

Fig. 311. A sketch showing how
the angle of incidence of the sun's
rays varies throughout the year. This
is at latitude 42<> N.

Digitized by

Google

608

AGRICULTURAL ENGINEERING

of Windows. The window casings should be
designed to intercept as Uttle of the direct sunlight as possible.
Stone or concrete walls of considerable thickness should be

beveled on the inside so
as to let in the full width
of the beam of sunshine
passing through the
glass. For this reason
windows that are long
vertically are more de-
sirable and more effi-
cient than those which
are wide but low. In
the latter instance the
casings and wall cut off
a large proportion of the
direct light admitted.
Again, wide, over-hang-
ing eaves cut off much
direct sunshine from the windows located directly below.

Size of Windows. No definite rules can be givenforthe
amount of window surface to provide in bams and other farm
buildings, owing to the fact that the efficiency of the windows
depends so much on their location. It is good practice, how-
ever, to provide one square foot of glass for every 20 to 25
square feet of floor surface. Judgment must be used in this
connection, varying the amount with the location and shape
of the windows. Dairy bams are generally provided with a
larger window area than horse bams.

There is a tendency to go to the extreme in lighting dairy
bams. Many bams have been built during recent years with
entirely too much window surface. Such buildings are too
cold when located in the northern climates, at least. Ade-

Figr. SI 2. A sketch showing the effect
of thick walls upon the amount of direct
sunligrht admitted, the greater efficiency
of deep windows over shallow windows,
and also the effect of over-hanging eaves.

Digitized by

Google

FARM SANITATION 609

quate window surface does not add materially to the cost of
the construction and should not be admitted for this reason.
Wide buildings and basement bams cannot be lighted well,
and for this reason should be guarded against. It is to be
remembered in this connection that natural lighting is only
one factor in providing sanitary quarters. Cleanliness and
ventilation are more important; but none of these features
should be neglected.

QUESTIONS

1. Describe the changes which have taken place in the natural
lighting of farm buildings.

2. What is the threefold purpose of the natural lighting of farm
buildings?

3. What value has direct sunlight in destroying disease germs?

4. Discuss how windows should be located to be the most effective.

5. What should be the general shape of windows, and what may
be said concerning the thickness of casings and width of eaves?

6. Discuss the relation between window surface and floor surface
in different types of buildings.

Digitized by

Google

CHAPTER LXXX
LIGHTING THE COUNTRY HOME

Development. It is extremely interesting to study the
development of the art of Ughting, or illumination; yet it is
not the function of this chapter to discuss this phase of the
subject. Our fathers and mothers were compelled while
young to depend on the tallow candle, the tallow dip, or
the light of the fire in the fireplace. History relates how
many of our famous men of the past century spent hours
in the flickering light from the "back log" poring over a book
which they were endeavoring to master. The petroleum
industry was not developed until 1860, and the general
use of kerosene in lamps did not come until many years
after this. The kerosene lamp, when provided with a
chimney to control the draft and produce more perfect com-
bustion, was a great improvement over the ill-smelling
and smoking tallow candle or dip.

The various soiurces of light for rural conditions are the
kerosene lamp, the gasoUne lamp or system, the acetylene lamp
or system, and the electric Ughting plant. Alcohol might be
bmned in lamps, but at its present cost cannot compete with the
petroleum oils. These various systems will be discussed in tiun.

The Unit of Light— The Standard Candle. In comparing
lamps it is necessary to refer to the unit of illumination, the
standard candle by which all lamps are rated. The standard
candle for the United States and Great Britain is the sperm
candle seven-eighths of an inch in diameter and burning 120
grains of sperm per hour. This standard is not very satisfac-
tory, as it tends to vary. The International Unit of Light

510

Digitized by

Google

FARM SANITATION 611

was adopted by the United States July 1, 1909, and is now the
legal unit of Ught, and is practically equal to the standard
candle.

The art of measuring the illumination of any source of
light is called photometry. The principle involved consists
in placing the source of light, or the lamp to be measured and
a standard lamp whose candle power is known, at such dis-
tances from a screen that the^intensity of the light from each
Is equal. As the li^t from a lamp passes out in all directions,
it is to be expected that the intensity of the light at all points
on the siu^ace of a sphere at a certain radius from the source
will be equal. As the surfaces of spheres vary as the square
of their radii, the intensity of light varies inversely as the
square of the distance from the source. This assumes that
the source of light is a sphere, which is not true.

Kerosene Lamps. Kerosene lamps are still in conmion
use, and, although they have some very serious objections,
their merits should not be entirely overlooked. In the first
place kerosene lamps are cheap a^ far as first cost is con-
cerned. The fuel is cheap and can be obtained almost any-
where. Kerosene lamps are quite safe; in fact, they excel
many others in this respect. There is more danger in the
matches than in the lamps themselves. The lamps are
readily portable, which is not true of all sources of artificial
light.

On the other hand there are many disadvantages. The
odor of kerosene lamps is not pleasant, although far more
oflfensive to some persons than to others. Kerosene lamps
require attention in the way of trimming the wicks and clean-
ing the chinmeys. If a large number of lamps are to be
cared for, the time required daily is considerable. Much
heat is developed by a kerosene light, which at times may
bo a serious disadvantage. The lamp also consumes a large

Digitized by

Google

512 AGRICULTURAL ENGINEERING

amount of oxygen and necessitates more rapid ventilation.

A large lamp will consmne more oxygen than several persons.

There is more or less smoke com-
ing from the flame, which settles
as soot upon the furniture and
walls of the room.

The light from a kerosene lamp
is a' yellowish orange. It is not
white enough to be a perfect light.
Authorities differ in regard to the
effect of the light from a kerosene
lamp upon the eye, but it is gen-
erally regarded as a quite suit-
able light. The addition of a
mantle, which is a net of rare
earths, to a kerosene lamp to in-
close the flame, increases the
efficiency many fold. This will
be shown definitely in the data
from tests which will follow.
Mantles, however, are very fra-
gile and increase the cost of keep-
ing the lamp in service. The
average kerosene lamp furnishes
light at the rate of 15 to 30 candle
power.

It is to be noted from the
table that the mantle has a de-
cided effect upon the efficiency
of lamps, raising the candle-
power-hours per gallon from 600

osene* lamp. The efficiency of to ovcr 3000. Gasolinc lamps are

thla lamp would be doubled by ;^ «^«i:4.„ «.«« 1««»..^« *^« 4.U^«*

the use of a mantle. m rcauty gas lamps, for tnev

Digitized by

Google

FARM SANITATIOIi

613

must convert the liquid into gas before it is burned. Gaso-
line lamps are either portable, with an individual generator,
or are connected to a system, with a common generator for the
entire system. Again, certain gasoline plants require a
special grade of light gasoline which is vaporized upon mixing
with air.

Gasoline Lamps. Gasoline lamps are not as safe as kero-
sene lamps, yet when properly handled should not be danger-

The efficiency of lamps.

Cost per

eandle

Candle-

candle-

Kind of lamp

Sise

Where tested

power

power-hn.

power-hr.
Kerosene

per gal.

at lie.

B.&H. Burner.

1}4 in. dia.

la. Exp. Sta.

33.5

877

.0125c

Common flat wick

IJ^ in.wide

Pa. Exp. Sta.

11.66

591 to

.017c

12.91

789

.017c

Rochester.

IJ^ in. dia.

Pa. Exp. Sta.

16.02
19.04

350 to
538

.023c

Saronia with Ar-

gand burner and

mantle

J4 ^' <li&*

Pa. Exp. Sta.

27.46
30.26

1312 to
1515

.008c

Chancester with

Argand burner

mantle

Pa. Exp. Sta.

30.6
32.4

3134 to
3402

.0034c

ous. They should be filled only by daylight, and care should
be taken not to let the gasoline become exposed to the air
either through a leak or by spilling. A gasoline lamp, unless
of the vaporizing type, requires some time for starting, and
must be heated before the gasoline can be generated. While
it is bummg, there is usually a hissing noise which is very
disagreeable. Gasoline lamps are universally mantle lamps,
and for this reason are very eflScient. The most efficient
lamps are those which furnish the liquid to the lamps under
pressure. The gasoline lamp consumes the oxygen of the
air and heats it much as the kerosene lamp.

17—

Digitized by

Google

514

AGRICULTURAL ENGINEERING

Efficiency of gasoline lamps

Kind of lamp

Where tested

Candle
power

Candle-

power-hrs.

per gal.

Cost per can-
dle-power-
hour at 20c.

Bracket lamp
Hanging lamp
Pressure lamp at 34 lbs.

Underneath generator

la. Exp. Sta.
la. Exp. Sta.
la. Exp. Sta.

Pa. Exp. Sta.

51.2

65.5

300.0

36to4G

2948
3180
4550

1885

.0068c
.0063c
.0043?

.0120c

Figr. 314. A gasoline lamp. The tubing is
coiled so as to appear in the pic-
ture.

QUESTIONS

1. What are the improved
systems of lightmg?

2. How were houses light-
ed by artificial means in early
times?

3. What is the common
unit of light, and explain how
it is established?

4. Explain how the illumi-
nation of any source may be
measured.

5. What are the advan-
tages and disadvantages of
kerosene lamps?

6. What effect does the
use of a mantle have upon
the efficiency of lamps?

7. Discuss the merits of
gasoline lamps.

8. How does the cost of
light from kerosene, alcohol,
and gasoline lamps compare?

9. Estimate tlie cost ci
lighting the average farm-
house during a period of one
year with tihe diC^erent
systems.

Digitized by

Google

CHAPTER LXXXI
THE ACETYLENE LIGHTING PLANT

The Principle of the Acetylene Plant. When a Ughting
system for the farm is desired which will furnish the equal of
city service, the acetylene plant is one of the first to receive
consideration. Acetylene gas is made by bringing calciiun
carbide in contact with water. In portable lamps the water
is allowed to drip upon the carbide; but with larger plants, the
carbide is fed into a rather large tank of water mainly to keep
the temperature of the gas as low as possible. The heating
of carbide and water is hke that of unslaked Ume and water,
and the resulting residue is the same — ^nothing more or less
than common whitewash.

Calcitim Carbide. The calcium carbide is made by sub-
jecting a mixture of coke and lime to the intense heat of the
electric furnace. The resulting product is of dark-gray color
with a sUghtly crystalUne structure. The carbide industry
is practically monopoUzed in this country by the Union Car-
bide Sales Company, from which all purchases must be made.
Distributing depots are located at various points throughout
the United States, there being one in each state, or perhaps
more in some instances. The cost of carbide at these depots
at the present time is $3.75 per himdred pounds. It isshipped
in metal cans as third-class freight. The carbide is no more
dangerous than unslaked lime; the only precaution necessary
is to keep it free from moisture. There are four sizes of car-
bide carried regularly in stock; viz.. Lump, Egg, Nut, and
Quarter. The last two sizes. Nut }/i inch by ^ inch, and
Quarter, J^ inch by 1/12 inch, are the two commonly used in
carbide feed generators.

615

Digitized by

Google

AORICULTURAL ENGINEERING

Agj^tAgoiB 0b8* Acetylene is a colorless, tasteless gas

^^ogcd entirely of carbon and hydrogen. It is lighter than

*!**^^uch heavier than coal gas. Acetylene bums with

**[V^ ^hite light, ahnost Hke sunlight. It is easy on the eyes

Figr. 816. A 86-Iight acetylene generator.

and enables one to distinguish colors accurately. The com-
bustion of acetylene deprives the air of about 23^ cubic feet
of oxygen for each cubic foot burned. The flame, for equal
candle power, produces less heat than the kerosene lamp.

Digitized by

Google

FARM SANITATION 617

Being a rich gas, acetylene will form a dangerously explo-
sive mixture with air; yet an explosive mixture, which must
contain between J^ to 25 times as much air as gas, is so
unlikely to occur, on account of the ease by which gas leaks
are detected, that accidents are seldom heard of.

Acetylene gas will cause asphyxiation, yet not nearly so
readily as coal gas, which is used for illumination in the cities.
No fatal results from inhalation are on record, and it is
claimed that death could not occur until the gas was present
in the proportion of at least 20 per cent.

Production of Acetylene Gas. When calcium carbide is
mixed with water, each pound should, if the carbide is chem-
ically pure, yield 5J^ cubic feet of gas. This gas is very rich,
containing about 1700 British thermal units per cubic foot,
nearly three times that of
coal gas. The commer-
cial carbide yields from
4Ji to 5J4 cubic feet, de-
pending somewhat upon
its purity, the moisture
absorbed,and the amount
of dust present. Theo-
retically, .562 pound of
water will be needed for
each pound of carbide,
but in practice as much

. , , J Fig. 816. A section of the generator

as eight pOUndd are sup- shown in Fig. si 5. a is the motor or

T J mi- X clockwork for operating the carbide feed,

piiea. 1 tie most com- B is the carbide feed. C is the weight for

. r 1 running the motor, D is the carbide bin,

mon size of burner used E is the agitator in the water tank for

1 y r • f J. £ Storing up the residue before cleaning,

consumes y^ cubic foot of p is the gas holder, G is the gas filter,

««« ^r.. l>^,,» ««^ «4,rr.« o and H Is the pipe line to supply lamps.

gas per hour, and gives a

25-candle-power light. Other standard sizes are the 1, ^,

and M cubic foot burners. These burners are all forked in

Digitized by

Google

618 AGRICULTURAL ENGINEERING

such a way that two jets of flame are directed toward each
other, forming a fan-shaped flame.

Mantles are not used with acetylene burners, owing to
the fact that it is almost impossible to light the gas without a
slight explosion or jar which would destroy the mantle. If
mantles could be used they would raise the efliciency of the
lamps many fold.

Cost of Light. If it is assumed that one pound of carbide,
costing $4 per hundredweight, will furnish five cubic feet of
gas, and that a burner using one-half cubic foot per hour will
furnish a 25-candle-power Ught, it is easy to calculate the cost
of acetylene light per candle-power-hour for comparison with
other lighting systems. Thus if 3^ cubic foot of gas costs4/l0
cent, which is the cost of 25 candle-power-hours of Hght, one
candle-power-hour will cost 1/26 of 4/10 cent or .016 cent.

In a test of a portable lamp, made at the Pennsylvania
agricultiural experiment station, from 127 to 140 candle-
power-hours were obtained from a poimd of carbide, costing
5 9/10 cents per pound. This would make the cost of light
per candle-power-hour .043 cent.

Essentials of a Good Acetylene Generator. All acetylene
light plants must have a generator whose function is to feed
the carbide to the water, or the water to the carbide, which
is less usual, as the gas is used. The essentials of a good
acetylene generator may be summarized as follows:

1. There should be no possibility of the existence of an
explosive mixture in the generator at any time. ' The National
Board of Fire Underwriters has prepared a Kst of generators
which have passed inspection ; and each buyer should see that
the make of machine purchased has been inspected and listed.

2. The generator must insure cool generation.

3. The construction must be tight and heavy enough to
resist rapid deterioration.

Digitized by

Google

FARM SANITATION 619

4. It should be simple in construction so as to be readily
understood and not likely to get out of order.

5. It should be capable of being recleaned and recharged
without loss of gas into the room.

6. There should be a suitable indicator to show how
much carbide remains unused.

7. The carbide should be completely used up, generating
the maximum amount of gas.

Size and Cost of Plant. Generators are made in various
sizes, the rating being based upon the number of j^foot
lights that can be supplied with gas. The sizes vary from
20-light to 1000-light, but 25, 30, and 35 are the usual sizes.
The list prices of these are 120, 135, and 150 dollars, respec-
tively. In addition to the cost of the generator, the cost of
the piping, fixtures, and installation must be added. For an
eight-room house, the total cost will be about as follows:

Generator $150

Piping system 40

Drain and foimdation for generator 10

Fixtures, eight rooms and basement 40

Bam additional 15

Total $255

It is to be understood that this estimate cannot be made
very definite owing to the varying number of fixtures required
and the cost of labor, freight, etc.

QUESTIONS

1. How is acetylene gas made? How is carbide made?,

2. Discuss the cost and sizes of carbide.

3. Describe the characteristics of acetylene gas.

4. Discuss the cost of light from acetylene gas.

5. What are the essentials of a good generator?

6. Itemize the cost of an acetylene plant.

7. What care should be used in installing an acetylene system?

Digitized by

Google

CHAPTER LXXXn
THE ELECTRIC LIGHTING FLAHT

Development Two great improvements have recently
been brought about which have done much to make the
private electric plant far more successful than ever before.
In the first placci the new timgsten incandescent lamp has
practically reduced the consumption of electricity per candle-
power-hour to about one-third the former rate. In thesecond
place, there have been some very decided improvements
in storage battery construction^ not only making them more
reliable, but cheaper.

Electric Light Illuminating eng^eers agree that the
incandescent electric light is the nearest approach to the ideid
light that is now to be obtained. Its first great merit lies in
its convenience. It is only necessary to turn a button or
switch and the light is on or off as desired. It is the cleanest
of all lights, no dust, no soot, and no odor. Furthermore, the
electric light does not vitiate the air by consuming the oxygen.
Of all lights it is by far the safest and may be taken directly
into places filled with combustibles.

The serious objection to the electric light which has been
raised in the past is its cost. The new tungsten lamp has
done much to remove this objection, where it can be used,
although it is rather fragile and cannot be used where the
lamp is subject to shocks or sharp vibrations. Further, the
cost of electric light may be somewhat overlooked on accoimt
of the advantages enimierated. The first cost of installing an
electric plant is large, but not so much greater than the cost
of installing an acetylene or gasoline plant. In addition to

520

Digitized by

Google

FARM SANITATION 621

lighting, the electric current may be used for other purposes-
small motors, electric irons, etc.

The Electric Plant It does not seem practical to install
an electric plant large enough to furnish power to the various
machines used on the farm. Not only would the cost of in-
stallation be very great, but such a plant when used for light-
ing would be very inefficient. An electric lighting plant
consists primarily of a source of power or a motor of some sort,
a generator or dynamo to furnish
the current, the wiring, the Ughts,
and, under all normal conditions,
a storage battery to supply cur-
rent when the motor and gen-
erator are not running.

The Source of Power. Water-
power makes an ideal power for
the plant, as it is almost always ^^^ ~^

very cheap. It is, however, not rig. tn, a i« the common
often available; hence the princi- fiTthe'^newTungsten^iampr which
pal source of power for the farm '■ "^""^ "^**"* •""**'*^
electric plant is the gasoline or kerosene engine. These, as
has been shown, have developed to the point where they are
quite reliable, and the power is furnished in small units at
a very reasonable cost. Furthermore, the gasoUne engine
requires the minimimi of attention while running, which
is an essential feature of the entire private electric plant.
Definitions. In discussing an electric plant, recourse
must be made to some electrical terms. Electric current has
two properties: (1) The pressure or the voltage, which is the
measure of the tendency on the part of an electric current to
flow; and (2) the amount of current flowing, or the amperage.
Thus a 110-volt lamp requires 110 volts of pressure or voltage
to make its filament glow brightly. If the lamp be a 16-
candle-power carbon filament lamp only one-half ampere will

Digitized by

Google

622 AGRICULTURAL ENGINEERING

pass through the lamp. The product of the volts by the
amperes gives the electric power in watts, the watt being the
imit of power. Thus for the lamp just referred to, the current
consumption would be 1 10 x J^, or 55 watts. One horsepower
is equal to 746 watts. The output of dynamos or generators
is rated in kilowatts, or units of 1000 watts. Electricity is
purchased by the kilowatt-hour, which is electric current at
the rate of one kilowatt continued for one hour. One kilo-
watt equals 1.34 horsepower; thus to drive a one-kilowatt
dynamo, a 1%- or 2-horsepower engine is provided, as some
power is lost in the friction of the dynamo itself.

Selection of the Plant. In deciding upon a plant one of
the first questions that arises is the matter of the voltage at
which the plant is to be operated. Electric light plants are
now made to furnish current at 30, 60, 110, or even higher
voltage. The common voltages are 30 and 110. The
lower voltages have some advantages; viz., (1) first cost of
thq storage battery is lower; (2) the battery has fewer parts;
(3) it can be used better with low candle-power lamps;
and (4) the lamps, having shorter filaments, are stronger.

The disadvantage of a low voltage lies primarily in the
fact that it is not standard with any Ughting plants and is
inconvenient to procure lamps and other fixtures for it.
There is a decided saving with high voltage, however, in
connection with the wiring, especially if the current is to be
transmitted far, since the size of wire required to furnish a
given fight with electricity varies inversely with the voltage.
In other words, a wire will transmit twice as much electricity
through a given size at 110 volts as at 55 volts.

If the maximmn number of 26-watt lamps in service at
one time does not exceed 20, or the demands upon the dynamo
from miscellaneous sources such as motors, fiat iron, etc.,
does not exceed 500 watts, a one-half kilowatt generator
may be used. A one-horsepower gasofine engine will furnish

Digitized by

Google

FARM SANITATION 623

the power unless required to do other work while running the
generator. K pumping, churning, and other forms of li^t
work are contemplated, a two-horsepower engine will usually
be found very satisfactory. The storage battery must con-
tain 56 cells, and if they are of the 20-ampere-hour size they
will furnish all of the lamps with current for four hours.

Fig. 318. Engine, dynamo, storagre battery, and switchboard of an elec-
tric lighting plant.

The Cost of the Plant. The total cost of plant may be
estimated as follows:

1 2-horsepower gasoline engine $125

1 J/^kilowatt generator 60

1 storage battery^ 20-ampere-hour, 56 cells at $2.50 140

1 complete switcnboard 75

17 tungsten lamps 7

12 carbK^n lamps 3

Wiring 60

Fixtures 30

Total cost .$490

The Cost of Light. The cost of operating the plant will
be principally that of gasoline, which, at the usual price, will

Digitized by

Google

514

AORICULTURAL BNOINSERINO

be between 1^ and 2 oentsper hour. Twenty 25-watt lamps
will furnish 400 candle-pow^. Thus the cost per candle-
power-hour might be at a minimmn .00375 to .005 cents. As
the plant will seldom be operated at full capacity, the aver-
age cost will be much greater, perhaps double.

Operation. The electric plant is not difficult to operate
by one who has some knowledge of electrical machinery.
The engine and the dynamo will not require a great amount of
attention. The storage must be supplied mih electrolyte
from time to time. The battery is also the least durable part
of the entire plant. Perhaps a new set of electrodes for the
battery will be needed at the end of five years. Agooden^e
ought to last at least ten years.

QX7BSTI0NS

1. What improvements have made the deotric li|^ting plants
practical for farm homes?

2. What are the advantages of dectric light?

3. Discuss the most serious objections to electric light.

4. Is it generally practical to install an electric lighting plant large
enough for power service?

5. Discuss the various sources of power for electric lighting plants.

6. Define voltage. Amperage.

7. What is a watt? A kilowatt?

8. What is the relation between watts and candle power with tung-
sten lamps?

9. What are the advantages of a low- voltage system?

10. What are its disadvantages?

11. Itemize the cost of an electric lighting plant.

12. Discuss the cost c^ electric light.

13. Discuss the care and maintenance of an electric lighting plant.

Digitized bv

Google

CHAPTER LXXXIII
HEATING THE COUNTRY HOME

Systems of Heating. There are four systems of heating
farm houses in use:

1. By stoves.

2. By a hot-air furnace.

3. By a hot-water furnace and radiators.

4. By a steam furnace and radiators.

Stoves. The first of these is in common use, and perhaps
Uttle can be written here which will add to the general infor-
mation upon the subject. The stove was invented to bum
coal shortly after coal was discovered, for the fireplaces of
the time were not adapted to the purpose. As usually
designed the stove is not an efficient device, as perhaps 50
per cent of the heat is lost up the chimney. It has other
more serious shortcomings, however. In the first place the
stove d >es not produce a uniform temperature, owing to the
fact that the air circulation within the room is not perfect.
The success of any heating system depends primarily upon
perfect circulation of the air. Air near the hot stove expands
upon heating, becomes fighter and rises to the ceiUng, and
colder air takes its place. As the warmest part of the stove
is several feet from the floor, the upper part of the room is
usually much warmer than the lower. The inconvenience of
handling and storing the fuel. in the room, and the dirt,
smoke and gases that are apt to result are also objectionable.

If several rooms are to be heated, the management of the
stoves becomes a troublesome matter. Almost any kind 6L
fuel may be used in a stove, which is an advantage decidedly

625

Digitized by

Google

526 AGRICULTURAL ENGINEERING

in its favor. Although coal requires less labor, wood is a
clean and very desirable fuel. In certain sections of the
country the fuel used is mainly com cobs and other trash, and
the stoves used are the so-called air-tight stoves which have
a large magazine into which a bushel or more fuel may be
placed at one time. This magazine obviates the necessity of
feeding the fuel at short intervals. There is, however, some
danger from the explosion of the gas which is generated from
fresh fuel before the flames start. The heat of the smoulder-
ing fire upon which fresh fuel is placed drives off certain
combustible gases, which are ignited as soon as a flame
starts up.

By far the most satisfactory stove for the cold winters of
the North is the hard-coal burner. When of sufficient size
and well designed, with a good large magazine, the hard-coal
burner may be used to heat several rooms to a comfortable
temperature. The high cost of hard or anthracite coal in
certain sections of the country renders the use of such a heater
quite expensive.

Radiators. In houses equipped with stoves an upper
room can be comfortably heated by extending the stove pipe
into the room and providing a radiator. This plan is highly
commendable, as there is no additional expense connected
with its use other than the cost of the radiator, which should
not exceed $8, the value of a good one.

Warm-Air Furnaces. Heating houses by means of warm-
air furnaces does not differ materially from the use of stoves.
The furnace is simply a large stove placed in the basement,
with pipes to convey the heated air to the various rooms
above. By placing the furnace in the basement many of the
objections to the stove are overcome. First, the dirt con-
nected with the firing and cleaning is kept where it is least
objectionable. Proper circulation of the air may be secured

Digitized by

Google

FARM SANITATION 527

by arranging the pipes so that the temperature may be kept
uniform in all parts of the house.

The warm-air furnace has an advantage in that a house
may be heated up quickly, and Ukewise the disadvantage that
the house will cool quickly when the fire goes down, owing to
the fact that there is no storage of heat. The hot-air furnace
is very bad about conducting dust and smoke into the rooms.
Often cheesecloth strainers are provided in the fresh air out-
lets to keep out the dust. The average life of a hot-air
furnace will not exceed 8 to 10
years, and when it becomes old the
plates are quite likely to be cracked
or warped in such a way that
there is a serious leakage of smoke
and gas into the rooms. It is to
be noted 'in this connection that
the furnace is so large that it must
be built in sections, and seams
cannot be avoided. As air does
not have the property of absorbing
a large amount of heat quickly,

the plates and castings are easily pi^. 319. ^ typi^ai warm-air
overheated. '"'"*^«-

In strong winds the circulation of the air in the flues is
seriously interfered with. Often there is a comer room more
exposed than the others that cannot be heated with the hot-
air system.

Installation. In planning a house in which the warm-air
system is to be used, thought should be taken to give the fur-
nace a central location, that there shall be no long horizontal
air pipes through which it will be difficult to start a draft.
The size of the hot-air furnace is usually designated by the
diameter of the fire pot, which raiiges from 20 to 30 inches

Digitized by

Google

628 AGRICULTURAL ENGINEERINO

and over. The hot-air system of heating is much less expen-
sive, as far as cost of installation is concerned, than the hot-
water or steam system.
The cost of a first-class
furnace with double pip-
ing to protect the wood-
work from becoming
over-heated, in a house
of six rooms, ought not
to exceed $200.

The Hot-Water Sys-
tem. The hot-water fur-
nace with suitable radi-
ators represents the most
perfect system of house
heating, but it is the
most expensive of all and
is slightly more difficult
to regulate. Water is
heated by the fiunace,
and the consequent ex-
pansion and reduction in
weight cause it to flow
to the radiators above,
where it becomes cooled
and consequently heav-
ier, causing it to flow
downward to be heated

Fiff. 820. A hot-water heating system, again. An expausion

The locomotive type of furnace or boiler. , , . -j j i_

although not in general use. Is said to be taUK IS prOVlCleCt aOOVO

quite satisfactory. n .1 i* < .

all the radiators to ac-
commodate the extra volume of the heated water. The
success of the hot-water system consists in providing a fur-

Digitized by

Google

FARM 8 ANITA TION 629

nace, piping, and radiators of sufficient size. The capacity of
a furnace depends primarily upon its heating surface, al-
though the size is commonly designated by the size of the
fire pot.

Radiators. Radiators, designed to give off heat from the
water heated in the furnace, are made of cast-iron, pressed
• steel, or pipe. In any case the amount of heat furnished is
determined by the amoimt of surface from which the heat
may radiate. This is always measured in square feet, and
one feature of the design of a hot-water system is to provide a
sufficient amoimt of radiating surface to heat each room.
Radiators may be obtained with greater or less number of
sections in various sizes, to furnish any amount of radiating
surface desired.

Estimating the Radiation. One rule for determining the
amount of radiation forcUmates where the temperature occa-
sionally falls below zero is as follows:

cubical contents of room

Square feet of radiation = h

200
square feet of glass

h lineal feet of exposed wall.

The hot-water system will successfully heat rooms on the
side of the house exposed to strong wind. It is much cleaner
and the plant will last at least twice as long as the hot-air
system. The cost will, however, be fropa one-half to double
that of the hot-air system. It is claimed that the hot-water
system uses one-third less fuel than the hot-air furnace.

A steam system may be installed for heating residences,
but it requires close attention and so is seldom used. In
large buildings and factories it is universally used, the use of
steam reducing to some extent the size and cost of piping.

Digitized by

Google

530 AGRICULTURAL ENOINEERINO

QUESTIONS

1. What are the four systems of heating farm houses now in use?

2. Discuss the advantages and disadvantages of stoves.

3. What are the fuels commonly used in stoves, and ndiat are the
advantages of each?

4. What is considered the most satisfactory stove for cold climates?

5. How may upper rooms be heated with the stoves below?

6. What are the advantages of a warm-air furnace over stoves?

7. How durable is the warm-air furnace?

8. How much will a warm-air furnace installation cost for a six-
room house?

9. What are the advantages and disadvantages of the hot-water
sjTStem?

10. Upon what does the ci4>acity of a hot-water furnace dei)end?

11. Of ^diat mateiials are radiators made?

12. Explain by a practical example how the radiating surface
required for a house may be estimated.

13. How will the cost c^ a hot-water system compare with a warm-
air system?

14. What are some of the objections to a steam heating Bym/em itn
farm houses?

Digitized by

Google

CHAPTER LXXXIV
VENTILATION OF FARM BUILDINGS

Importance of Ventilation. One of the most important
featm*es involved in the design of farm buildings is that of
ventilation. It is generally recoginized that men and animals
must' have fresh air, and the most favorable conditions for
life and health are attained when the air is as pure as the open
atmosphere. It is not practical to provide air as pure as this
to animals housed in buildings designed primarily for shelter
and warmth.

The Standard of Purity. The standard of purity, or the
extent to which pure air maybe vitiated with expired air and
still be fit to breathe, is a much-argued point. For conven-
ience, the purity of air is designated by the number of parts
of carbon dioxide in 10,000 parts of air. Pure air contains
about four parts of carbon dioxide in each 10,000 parts.

De Chaumont, an authority on ventilation, holds that six
parts of carbon dioxide in 10,000 parts of air should be the
standard, and other authorities recommend various and
greater amoimts. The late Professor F. H. King, of Wiscon-
sin, recommended 16 parts as the correct standard, but em-
phasized the great need of experiments to determine definitely
the correct standard. There is little doubt that if this lower
standard were maintained generally, ventilation conditions
would be much better than they are now.

Purpose of Ventilation. The purpose of ventilation is
threefold: (1) To supply pure air to the lungs of the animals;
(2) to dilute and remove the products of respiration; and (3)
to carry away the odors or the effluvium arising from the

531

Digitized by

Google

632

AGRICULTURAL ENGINEERING

excreta. The first of these is the all-important purpose; for

no animal can live more than a few minutes without air, but

is able to go for some time witiiout either food or water. The

quantity of air breathed daily by an animal greatly exceeds

the total quantity of food and water. This is indicated by the

following table:

Amount of air breathed by different animals.
(CoUins Tabled

Per hour

Per 24 lioura

Hone

Cow

Pig

Sheep

Cu,/L
141.7
116.8
46.0
30.2
17.7
1.2

Pmmdt

272

224

Cu.ft.

3402

2804

1103

726

Man

Hen

425
29

To maintain the standard set by Professor King, which

requires that the air at no time BhaXL contain more than 3.3

per cent of air once breathed, the following amounts of air will

be required each hour for the various animals indicated.

This standard may be stated as 96.7 per cent, representing

the purity of the air, and, as before stated, it is equivalent to

between 16 and 17 parts of carbon dioxide per 10,000 parts

of air.

Amount of air required per hour to maintain a standard of g6./ per
cent.

Horses 4296 cu. ft. per head

Cows 3542 " " ' '

Swine 1392 " «

Sheep 917 " "

Hens 35 " "

Man 537 " "

Ventilation finally resolves itself into the problem of find-
ing a process of dilution or mixing the air in the building with

Digitized by

Google

FARM SANITATION 533

fresh air fast enough to prevent the air from becommg foul
beyond the pennissible standard. The process of dilution
may be accomplished in at least four different ways, as follows :

1. By a process of diffusion through cloth curtains.

2. By the action of winds.

3. By the difference in weight of masses of air of un-
equal temperature.

4. By mechanical methods.

Cloth Curtain Ventilators. Poultry houses quite gener-
ally and dairy bams in several instances have been ventilated
by providing thin muslin or cheesecloth curtains in place of
the usual window glass. The theory of ventilation in this
case holds that there is a diffusion of the foul air outward and
the pure air inward through these
curtains. Experiments which have
been conducted to date, to deter-
mine definitely the efficiency of this
system, would indicate that it is r
imsatisfactory and unreliable. It
is quite impossible with any rea-
sonable amount of curtain surface
to provide the necessary pure air.

Action of Winds. The action
of the winds is one of the sim-
plest methods of producing venti-
lation. For instance, the wind pro-
vides ventilation when two windows Fig. 821. A window ar-

. ransred so as to allow air to

are opened on opposite sides of a enter with the least draft. It

- •ij. CI i_ A ^^^ **® hinged at the bottom

DUlldmg. DUCh an arrangement and made to close between the

would not be satisfactory on ac-

coimt of the direct drafts produced, subjecting the animals
to chills. The dangers from drafts are overcome to a large
extent by providing suitable inlets and outlets.

Digitized by

Google

684

AGRICULTURAL ENGINEERING

The Sheringham valve makes a satisfactory inlet. This
is arranged by hinging the window at the bottom and allow-
ing it to drop inward at the top between cheeks or triangular-
shaped side pieces. The air in striking the inclined window
is thrown upward toward the ceiUng and is not allowed to
pass directly onto the animals which may be housed in the
building. The fresh air is diffused through the room and the
foul air passes out through suitable flues, not imUke those to

be described later. Cowls
or cupolas are used in
connection with outlet
flues and are designed in
such a manner that the
winds in blowing across
them produce a suction
or aspirating effect in the
flues.

Temperature System.
The principle that heated
air rises is the theory
basis of the majority of
the successful ventilating
systems now in use. The
King system, named after
the designer, the late
Professor F. H. King, uses
this principle as well as
the principle that foul
air is heavier than pure
air when both are at the same temperature, and tends to
settle towards the floor. For this reason, the inlets in the
King system discharge pure air near the ceiUng and the out-
let flues receive the air near the floor.

Figr. 822j Showing one method of ar-
ransrlng the outlet flues in the King sys-
tem. The fluea may be brought together
to form a common outlet.

Digitized by

Google

FARM SANITATION

535

Size of Inlets and Outlets. Professor King advises four
square feet each of outtake and intake flues for each 20 adult
cows, for an outlet flue 20 feet high; or, in other words, 36
square inches of crossHsection of flue should be provided for
each cow. If the outlet flue be 30 feet high, 30 square inches
of cross-section will be sufficient. To be successful, there
should be a rather large number of intakes and few out-
takes. The outtakes should be air-tight, as straight as pos-
sible, and as smooth as practical on the inside. One common
cause of failure of this system of
ventilation is incorrectly con-
structed outtakes or outlet flues.
Often the flues are made of one
thickness of tongued and grooved
lumber which dries out and leaves
open cracks which prevent the flues
from working. Again, it is a com-
mon occurrence to find that the
flues are made with many sharp
tmns which restrict the flow of
air through them. A good cupola,
so designed as to produce a suction
on the flues connecting into it when the wind is blowing,
increases the efficiency of the system materially.

Mechanical Ventilation. Mechanical ventilation is prac-
tically unknown at the present time for farm buildings. It
consists in providing fans or other positive means of forcing
air into or out of a building, and is considered the only
modem method of ventilation. The time may come when
it will be considered in connection with farm buildings. All
other systems depend more or less upon varying conditions of
wind and temperature, which cannot be controlled.

Fig. 323. Different methods
of arransring the inlet flues in
the King system of ventila-
tion.

Digitized by

Google

Digitized byVjOOQlC

PART NINE— ROPE WORK

CHAPTER LXXXV

ROPE, KNOTS, AND SPLICES

A practical knowledge of the correct ways of tying,
iiitching, and splicing ropes is valuable to any farmer. His
work is such that an extended use must be made of ropes;
and such knowledge will not only be convenient and save
time, but will also be a means of averting accidents. Only
the more important knots, hitches, and splices will be dis-
cussed.

EJnds of Rope. Mention has been made in a former
chapter concerning the various kinds of rope in use for
transmitting power. The rope used for general purposes
about the farm is hemp rope. As most of it is made from
Manila hemp imported from the Philippine Islands, it is
generally known as Manila rope. Cotton rope is some-
times used for halters or ties.

In making rope, the fibers are first spim into a cord or
yam, being twisted in a direction called "righthand." Sev-
eral of these cords are then made into a ''strand" by being
twisted in the opposite direction, or "lefthand." The rope
is finally made up of three or four of these strands twisted
"righthand," and is known as a three- or a four-strand rope,
depending upon the niunber of strands used. The four-
strand rope is constructed on a core, and is heavier, more
pliable, and stronger than the three-strand, in any given size.

Strength of Rope. The following table gives the strength
and weight of some of the common sizes of three-strand
Manila rope when new and free from knots. The smallest

637

Digitized by

Google

638

AGRICULTVRAL ENaiNEERING

size of pulley upon which the rope should be used is also
given. The working strength, or the greatest load the rope
should carry with safety, is given as about one-seventh of the
breaking load.

Strength of dijSfererU sizes of three-strand Manila rope, and

size of puUey

to use.

Diameter

Weight per
100 Ibi. rope

Safe load

Breaking load

Diameter of
puUey

InchM

Pound$

Potmda

P<mnd9

Inches

400

130

900

7.6

230

1620

13.3

410

2880

16.3

520

3640

23.6

775

5440

28.3

925

6480

Good Knots. The three quaUties of a good knot have been
stated as follows: "(1) Rapidity with which it can be tied;
(2) its ability to hold fast when pulled tight; and (3) the
readiness with which it can be undone.^' In Kent's Mechan-
ical Engineer's Pocket Book it is stated, "The principle
of a good knot is that no two parts which would move in
the same direction if the rope were to slip
should lay along side of, and touching, each
other."

Parts of the Rope. For the sake of clear-
ness in the discussion of knots which is to
follow, the student should understand what
is meant by the following parts of a rope:
The standing part is the long unused

B bighf-^'c^ fo*op! P^^* ^^ *^® rope, as represented by A,
D. end. ' • ' Fig. 324.

The bight is the loop formed whenever the rope is turned
back upon itself, as B.

The
parts of a rope:

Diqitized bv

Google

ROPE WORK 539

The end is the part used in leading the rope, as Z) in the
figure.

A loop is made by crossing the sides of a bight, as C.

KNOTS

The squarC) or reef, knot is one of the commonest knots
used in tying together
ends of ropes or cords. It

is the knot that can hest?v'^vj^\&swi^p;^>^^^^^^^^^^
be used in bandaging or
in tying bundles. It does ^*^- ^''' ^^"^^^' °' ^^"' ^'^"'•
not slip and is quite easily untied. In tying the square
knot, the ends are crossed, bent back on themselves, and
crossed again, making the outside loop pass around both strands
of the opposite end. As usually tied both ends are on one
side as shown in Fig. 325. Then it will not sUp.

The Granny f or False Reef, Knot. If the ends of the rope
are crossed finally in the wrong direction, the result is not

the true square knot but

what is known as the

granny or false reef knot,

as shown in Fig. 326. This

knot, when compared with

the true reef knot, illustrates the first principle of knots.

It is not a good knot, and is given to explain this principle.

The sheet bend or weaver's knot is universally used

by weavers in tying together two ends of threads and yams.

Flgr. 326. Granny knot, or false reef.

Figr. 827. Sheet bend, or weaver's knot.

Digitized byVjOOQlC

640 AGRICULTURAL ENGINEERING

and is a good knot inasmuch as it is very secure, can be rapid-
ly tied, and easily untied. This knot is tied by forming a
loop with one rope end, as shown in A, Fig. 327, and then

passing the other end back
through this loop, as shown
at B. When pulled tight
the knot takes the form
shown at C.

The bowline knot is the
best knot for forming a
noose or loop
which will not

Fig. 328. Bowline knot. ^jj^ ^j^^^^ ^^^^

strain, and which can be easily imtied. Fig. 328
shows one method of tying the bowline. In tying
this knot a loop is formed in the standing parts of
the rope, as shown at the left in Fig. 328; then the
end of the rope is passed through this loop around
the rope and back through the loop, as shown at
the right. This, perhaps, is the simplest way of ^r ^^
tying this knot, but there are several other ways, siip knot.

The halter, slip, or running
knot is used where it is desired
that the rope shall bind, as on a
post when tying a halter rope.
This knot is made by bending the
end of the rope over itself and
carrying it around the standing part
of the rope and back through the

Fig. 330. Hitching tie. loop thuS fOHUed.

Often, in tying a halter rope, it is safer to use a bight of
the rope through the knot and then pass the end of the rope
through the loop so formed, as shown in Fig. 330. This
knot unties somewhat more easily.

Digitized by

Google

ROPE WORK

541

HITCHES

The Half Hitch. The half hitch, as shown in Rg. 331,

is not very secure, but is easily made.
The clove hitch, as shown in fig. 332, is

more secure than the half hitch. It is

often used to fasten timbers together.
The Timber Hitch. The tunber hitch,

(Fig. 333) is used in attaching a rope to

timber, for hauling, and simihw purposes. ^^ ^^^ jj^j,

It is made by leading the end of the rope ^"^^i*-

around the timber, then around the standing part, and back,

making two or more turns on its own part. The strain in

the rope will prevent the rope
from slipping.

fc'b^^^^'^^g5^1S^'^^^ The Blackwall hitch is used to

attach a rope to a hook; and, al-
though simple, it holds the end very
securely. See Kg. 334.

Two Half Hitches. Two half

hitches may be used to good advantage, for they prevent

the rope from slipping under any strain. They are easy to

form, as may be learned from Fig. 336.
The Sheepshank. The sheepshank

is used in shortening a rope. It is

made by gathering up the amount to

be shortened and taking a half hitch

around each end, as shown in Fig.

336. If it is desired to make the

knots more secure, the ends of the

rope may be passed through the bights.

Fler. 882. Clove hitch.

Flgr. 333. Timber hitch.

FINISHING THE END OF A ROPE

Whipping. Whipping is one of the best ways of prevent-
ing a rope from raveling; and, as the size of the rope is not

Digitized by

Google

642 AGRICVLTURAL ENGINEERING

materially increased, it can be used where the
rope is to pass through pulleys and small
openings. Good, stout wrapping cord should
be used for the whipping. A loop of cord is
laid along the end of the rope, as shown at A,
Fig. 337. The loop is then used to wrap the
rope, allowing the side of the loop to pass over
the end of the rope. After the rope has been
wrapped for a sufficient distance, the ends of
the cord are pulled tight and then cut off, 'as
shown at B.

Crowning the end of a rope
consists in unraveling it for a
Pig. 834. Black- short distaucc, usually 6 or 6
inches; then knotting the strands
and turning them back and weaving them
into the rope. This increases the size of the
rope end, but makes a very firm
finish. The strands are first
knotted as shown at A, Fig.
338. Then with the aid of a
pointed, smooth, hardwood stick
the loose strands are woven al- pig. 335. two
temately over and under the ""^'^ '**'"''""•
strands in the rope. When passed under
three or more strands of the rope in this
manner, the end of each loose strand may be
cut off. To prevent kinks and to make a
smoother finish, the loose strands may be
slightly untwisted as they are woven into the
_ rope. When finished, the crown should have

Bhefisha^k! the appearance of D, Fig. 338.

Digitized by

Google

ROPE WORK

643

SPLICING

The Short Splice. The short splice makes the rope larger
at the spUce, as a double number of strands are woven into
the rope at one place.
Thus in case of a
three-strand rope the
spUce is six strands
thick at the spUce.
This splice cannot well
be used where the rope
is to run over pulleys.

To make the shprt splice, the ends of the rope are unlaid
for a suitable length, which will vary from 6 to 15 inches,
depending on the size of the rope. The strands are then
locked together by tying by pairs strands from opposite ends
of the rope, with a simple overhand knot, as shown at S,
Kg. 339. After tying, the strands are woven into the rope
in each direction by opening the rope with a hardwood pin
and tucking them under every other strand of the rope.
This tucking may be repeated two or more times and the
ends then cut off, leaving a splice as shown at D.

Flgr. 837. Whipping.

Fig. 338. Crowning.

The Long Splice. The long spUce is not so bulky as the
short splice, and should be used where the rope is to run

Digitized by

Google

644

AGRICULTURAL ENGINEERING

over pulleys. It is so made that ends of the strands are
joined at different places, making the largest number at any
one place only one greater than the number of strands in the

Fisr. 339. Short splice.

rope. Thus with a three-strand rope the number of strands
tlu-ough the splice is four. In making the long splice, a much
longer length of each end of the rope is unlaid. For a J^-inch
rope, this should be about 18 inches; for a J^nch rope, 24
inches; for a ^-inch rope, 36 inches; for an inch rope, 36

rTTT^yiitt ^*^*^|y'p*^^^^'n|y'

Fig. 340. Long splice, three-strand rope.

inches and so on. After unlaying the rope ends for the proper
distance, they are locked together as shown at A, Fig. 340.
By unlaying one strand from each of the rope ends and filUng

Digitized by

Google

ROPE WORK

64§

in with one of the loose strands, bring the splice into the
form shown at B. Then tie the strands and weave the loose

ends into the rope as
in the case of the
short splice, as shown
at C, finishing the
spUce as shown at D.
The Side Splice.
The end of a rope
may be joined into
the side of the rope
in a similar way, as
is shown in Fig. 341.
Rope Halters.
Rope halters can be
conveniently made in a variety of forms, as shown in A, B,
and C, in Fig. 342. T}ie size of these halters will depend
upon the size of the animals for which they are intended.

Fig. 341. Side splice.

FIgr. 342. Rope halters.

Their making does not require the use of any new princi-
ples other than those discussed.

QUESTIONS

1. To what practical use may a knowledge of knots be put?

2. Of what materials are ropes made?
IS—

Digitized by

Google

546 AGRICULTURAL ENGINEERING

3. Describe the making of a rope.

4. What axe of rope should be used for a 500-pound load?
A 1000-pound load?

5. What are three quahties of a good knot?

6. What is the most important principle of the knot?

7. Name and describe the parts of a rope.

8. Describe the following knots, and explain where they are useful:
The square or reef knot; the granny knot; the weaver's knot; the bow-
line knot; the halter or slip knot.

9. Describe the following hitches and their use: The half hitch;
the clove hitch; the timber hitch; the Blackwall hitch; two half hitches.

10. What is the sheepshank used for? Describe how it is made.

11. Explain how the end of a rope may be finished by whipping. By
crowning.

12. Describe the making of a short splice. The long splice. The
ride splice.

13. Describe how three styles of halters may be made.

Digitized by

Google

INDEX

Acetylene plant, 515; cost of,
519; generator, 517; produc-
tion of gas, 517.

Agricultural Engineering, de-
fined, 13.

Air, amount breathed by ani-
mals, 532; amount in gas
mixtures, 350; standard of
purity of, 531.

Air pressure water system, 494.

Alfalfa, under irrigation, 119.

Alfalfa harrow, 217.

Ammeters, 358.

Angle of incidence of sun's
rays, 507.

Angle of traces, 331.

Areas, computing, 34; problems,
37.

Arrows, 21.

Ash wood, use in tools, 196.

Babbitting boxes, 192.

Ball bearings, 191.

Balloon frame, for houses, 455.

Barns, dairy, 436; horse, 442;
round, 449.

Barn framing, 445.

Basin method of irrigation, 132.

Bathroom fixtures, 499.

Batteries, 358.

Beams, strength of, 406; form-
ula for, 408.

Bearing of a line, 53; of a
plow, 201.

Bearings, ball, 191; adjust-
ment of, 193; harrow, 218;
ring oiling, 191; roller, 191;
self-aligning, 190.

Beech wood, 196.

Belting, 320; canvas, 321;
horsepower of, 320; lacing
of, 322; leather, 321; rubber,
321.

Bench marks, 43, 49.

Bending moment, 406.

Berm, 104.

Bessemer steel, 197.

Binder, grain, 244; adjustment,
248; causes of failure to tie,
248; engine drive, 246, 269;
operation of, 246; selection,
244; size, 244; tongue truck,
246.

Birch wood, for machines, 196.

Blower, ensilage, 275; thresher,
280.

Boiler, steam, 376; capacity
of, 379; locomotive, 378;
management of, 383; return
flue, 379; vertical, 377.

Boiler feeder, 382.

Border method of irrigation,
133.

Boxes, of machines, 190; bab-
bitting, 192; enclosed wheel,
191.

Brick, building, 410.

Brick roads, 165.

Bridges, concrete, 177; design
of, 175; foundation for, 177;
importance of, 175; size, 175.

Bridging, 456.

Brooks, as farm water supply,
484.

Bubble tube, 44.

Buildings, farm, capital invest-
ed in, 395; heating, 525;
lighting, 506; location of,
395; ventilation of, 531.

Digitized by

Google

548

INDEX

Cable transmission, 324.

Calcium carbide, 515.

Canals, 122.

Candle, standard, 511.

Canvas belting, 321.

Capillary water, 57.

Carburetors, 345, 351.

Carriers, hay, 271.

Cart, harrow, 213.

Cast iron, as machine material,
196.

Cast steel, 197.

Catch basin, 99.

Cement, Portland, 410.

Center, dead, 387.

Cesspool, 501.

Chaining, 23, 24.

Check method of irrigation, 131.

Chilled cast iron, 197.

Clay roads, 153.

Clutch, on tractors, 372, 392.

Coefficient of friction, 188, 189.

Combustion of gases, 344, 350.

Compass, 53.

Component forces, 314.

Compound engines, 386.

Compression, 352.

Concave, 279.

Concrete, 411; proportions for,
412; reinforcement of, 412.

Concrete roads, 166; bridges,
177.

Connecting rod, 385.

Contour maps, 52.

Com harvesters, 251; binders,
252; buskers, 256; pickers,
254; shocker, 254; shredder,
256; sled cutters, 251.

Com planters, 231; adjust-
ment, 236; conveniences,
235 ; dropping mechanism,
226; essentials of, 231; fur-
row-openers, 234 ; graded
seed for, 238; wheels, 234;
variable drop, 233.

Correction lines, 39.

Cow ties, 440.

■Crank shaft, 385.

Crowning a rope, 542.

Crown sheet, 378.

Cultivators, 237; construction,
238; balance frame, 240;
disk, 242; guiding devices,
241; seats, 241; selection
of, 237; surface, 242; walk-
ing, 238; wheels, 240.

Culverts, 175; concrete, 178;
design of, 175; importance
of, 175; pipe, 178; size, 175.

Cutters, ensilage, 273; con-
struction, 276; elevating me-
chanism, 275 ; mounting. 275 ;
selection of, 276; self-feed,
275; types, 273.

Cylinder, 488; threshing, 278.

Dairy barns, 436; construction
details, 437; essentials of,
436; types, 436.

Datum, 42.

Dead center, 387.

Declination of the needle, 53.

Deep-tilling machine, 206.

Deere, John, 181.

Differential, 393.

Disk harrow, 213.

Disk plow, 204.

Ditches, cost of digging, 101;
digging for tile, 86, 93; fill-
ing, 96; grading, 89; open,
103.

Ditching machines, 87.

Draft, of plows, 204; principles
of, 330.

Drainage, 56; benefits of, 61;
districts, 108; history of, 56;
land drainage, 86; lands
needing, 58 ; open ditch, 103 ;
systems of, 67; underdrain-
age, 59.

Drainage districts, 108; assess-
ments, 109; defined, 108;
laws for, 108 ; survey of, 109.

Drainage engineer, 64.

Drainage system, 67.

Drainage wells, 100.

Digitized by

Google

INDEX

549

Drawing instruments, 28.

Drills, 225; adjustment of, 229;
force feeds, 227; furrow-
openers, 225; horse lift, 229;
press drill, 228; seed tubes,
228; selection of, 228.

Dynamometers, 317.

Dynamos, 358.

Earth roads, 147; construction,
147; crown, 149; drainage
of, 147; extent, 147; grades,
151; maintenance, 150.

Eifflciency of lamps, 513; of a
machine, 186.

Elasticity, defined, 404.

Electric light, 520; cost of.
524; plant, 521; selection of
plant, 522; source of power,
521.

Electrical terms, 522.

Elements of machines, 186.

Elevation of a point, 42.

Elevators, ensilage, 275; por-
table farm, 287.

Energy, kinds defined, 313.

Engineer, drainage, 64.

Engineering, defined, 13.

Engine gang plows, 208.

E^ngines, gasoline or oil, 344;
measuring power of, 316;
operation of, 350; steam,
376, 385; tractors, 370, 389.

Ensilage machinery, 273.

Equilibrium, defined, 402.

Essentials of a machine, 187.

EiVeners, 334; four-, five-, and
six-horse, 336; placement of
holes, 334; plain, 337; three-
horse, 335.

Factor of safety, 405.

Fanning mills, 282.

farmhouse, the, 451; con-
structing, 455; features of
construction, 451 ; location
of, 451; plan of. 452.

Farm machinery, 180.

Farm mechanics, defined, 15.

Farm sanitation, 480.

Farm structures, 395.

Feed mills, 298.

Feed water heater, 382.

Fields, leveling, 52.

Fixtures, bathroom, 499 ;

plumbing, 497.
Flagstaff, 21.
Flooding method of irrigation,

131.
Flow of water, in ditches, 105;

in pipes, 491; in tile, 78.
Foaming in boilers, 383.
Foot pound, defined, 314.
Force, action of, 402; defined,

314.
Forks, hay, 270.
Friction, coefficient of, 188, 189;

defined, 187; of rest, 188.;

rolling, 188.
Friction gearing, 325.
Fuels, for engines, 344.
Full frame, 445, 455.
Furnaces, for boilers, 377; for

houses, 526.
Furrow method of irrigation,

133. *
Fusible plug, 382.

Gang plows, 201; engine, 208.

Gas mixture for engines, 350;
testing, 352.

Gasoline engines, 344; classes,
344 ; estimating horsepower
of, 367; four-stroke cycle,
346; fuel for, 344; operation
of, 350; for pumping, 486;
selection of, 361; testing,
366; two-stroke .cycle, 347;
types, 345; use on binders,
246, 364.

Gasoline lamps, 514.

Gas tractors, 370.

Gauge, cocks, 380; glass, 381;
pressure. 381.

Gearing, for transmitting pow-
er, 324; traction, 373, 393.

Digitized by

Google

560

INDEX

Goyemor, engine, S87.
Graders, grain, 282.
Grading tilb drains, 73, 89.
Grain, under irrigation, 118.
Graphite, as a lubricant, 189.
Gravel roads, 154; binder, 155;

cost of, 158; drainage of,

156: maintenance of, 158;

surface construction, 156.
Grease cups, 192.
Grip, of horse, influence on

draft, 331.
Gnnter's chain, 18.
Gunter's chain measure, 19.

Halters, rope, 545.

Harrow attachment for plows,
219.

Harrows, 211; cart for, 213;
construction of, 212, 215;
disk, 213; smoothing, 211;
spring-tooth, 213.

Harvester, com, 251; grain,
244.

Hay machinery, bam, 270;
field, 258.

Heating systems, 525; fur-
naces, 526; stoves, 525.

Hickory wood, qualities and
uses, 196.

HiUside plow, 207.

Hitch, length of, influence on
draft, 332.

Hitches, 541.

Hog houses, 414; individual,
417; large, 419.

Horse, amount of service from,
329; as a motor, 327; capa-
city of, 328; draft, 330; size
of teams, 329; weight, etc.
of, influence on draft, 330.

Horse bams, features of con-
stmction, 442.

Horsepower, 314 ; estimating,
engines, 316, 366.

Hot water heating system, 528.

Husker, com, 256.

Hussey, Obed, 181.
Hydrostatic water, 57.

Ignition, in oil engines, 354;
jump-spark system, 357;
make-and-break system, 355.

Implement, defined, 186.

Implement house, 473; details
of constraction, 474; loca-
tion, 473; size, 473.

Incandescent lamp, 521.

Injector, 382.

Instruments, for leveling, 42;
for measuring, 18.

Iowa silo, 469.

Iron, cast, 196; wrought, 197.

Irrigation, 111; amount of wa^
ter used in, 117; applying
water in, 129; crops grown
by, 118; history of, 112; pre-
paring land for, 130; pur-
poses of, 113; sewage dis-
posal by, 138; supplying
water for, 122.

Irrigation culture, 115; in
humid regions, 136.

Jacks, lifting, 287.
Journal, 190.
Jump-spark ignitors, 357.

Kerosene lamps, 511.

Knots, essentials of a good,

538 r kinds, 539.
Knotter, binder, 248.
Kutter's formula, 105.

Labor, farm, influence of ma-
chinery on, 181; of inconven-
ient buildings on, 395.

Lakes, as farm water supply,
484.

Lamps, efficiency of, 513; gas-
oline, 514; kerosene, 511.

Land rollers, 220.

Laundry, in farmhouse, 454.

Laying out the farm, 396.

Leaks, In oil engines, 353.

Digitized by

Google

INDEX

651

Leather belting, 321.
Lettering, 32.

Level, 45; adjustments of, 46.
Leveling, definition of terms,

42; practice, 49; tile drains,

73.
Light, unit of, 511.
Lighting systems for buildings,

acetylene, 515; development,

510; laipps, 511; natural,

506; electric, 520.
Lime, for motar, 410.
Linear measure, 19.
Liners, 193.
Link belting, 323.
Loaders, hay, 266.
Locomotive boiler, 378, 528.
Lubrication, 189; choice of

lubricant. 189.

Mccormick, Cyrus W., 181.

Macadam roads, 160; bitumi-
nous, 163.

Machine, . defined, 186; ele-
ments of, 186.

Machine shed, 473.

Machinery, farm, 180; binder,
239; care of, 309; corn
harvester, 252 ; com shellers,
299; definitions and princi-
ples, 186; elevators, 287;
ensilage, 273; fanning mills,
282; feed mills, 298; hay,
258; infiuence of, 181; in-
troduction of, 180; manure
spreaders, 292; motors, 313;
threshing, 27S; spraying,
303; windmills, 339.

Magnetos, 358.

Manure spreaders, 292.

Malleable iron, for machines,
197.

Maps, contour, 52; final, 76;
preliminary survey, 66.

Map making, 28.

Maple wood, qualities of, 196.

Markets, influenced by roads,

143.
Materials, mechanics of, 402,

406; used in machinery, 195.
Measurement of power, 316;

of water, 134.
Measuring, 18; instruments

for, 20; tables for, 19.
Mechanics, defined, 15.
Mechanics of materials, 402,

406.
Meridian, guide, 39; principal,

38.
Metes and bounds, surveys by,

40.
Modulus of rupture, 408.
Modulus of section, 407.
Moment of a force, 402.
Monuments, 40.
Motors, classification of, 344;

farm, 313 ; horses as, 327.
Mowers, 258; adjustment, 262;

construction, 258; size, 258;

types, 258.

Newbold, Chas., 180.
Notes, field, 24, 50.

Oak, as material for machines,

196.
Oil cups, 192.
Open ditches, 103; capacity of,

104; construction of, 103;

cost of, 104; disadvantages

of, 104.
Orchard irrigation, 121.

Pacing, 23.

Perry pneumatic water supply
system, 495.

Pine, for machines, 196.

Pipes, water, 491; fiow of wa-
ter in, 492; sizes, 491; sys-
tems, 492.

Plank frame for barns, 445.

Planter, corn. 231.

Plastering, 458.

Digitized by

Google

552

INDEX

Plows, 199; adjustment, 200;
construction, 200; disk, 204;
draft of, 204; engine gang,
208; gang, 201; barrow at-
tachment for, 219; hillside,
207; selection of, 199; size,
199; sulky, 201; types of,
199.

Plumb line, 43.

Plumbing, for houses, 497; fix-
tures, 497.

Plungers, for pumps, 489.

Poncelet's formula, 79.

Population on farms, 183.

Poplar wood, qualities and
uses, 196.

Potatoes under irrigation, 120.

Poultry houses, 425; construc-
tion details, 429; location,
425; size, 425; types, 432.

Power, defined, 314; for light-
ing plant, 521; for pumping,
486; from horses, 327; meas-
urement of, 316; required
for machinery, 361; trans-
mission of, 320.

Power mills, 298, 340.

Preliminary survey, 64.

Pressure gauge, 381.

Prime movers, 313.

Profile, leveling, 49; grade, 74.

Prony break, 316.

Pumps, 487; important fea-
tures of, 488.

Pumping plant, 486.

Pumpinng water, cost of with
engine, 363; for irrigation,
125.

Pulleys, 322; calculating speed
of, 323.

Purlines, 445.

Pulverizers, 221.

Quadrants, for transmitting
power, 324.

Radiation, estimating, 529.
Radiators, 526. 529.

Rakes, sweep, 268; sulky, 259;

side delivery, 260.
Range of townships, 39.
Range pole, 21.
Rating, of tractors, 392.
Rectangle, area of, 34.
Reinforcement of concrete,

412.
Repair of machinery, 309.
Reservoirs, for irrigation, 123;

home water supply, 493.
Resultant, defined, 314.
Resurveys, 40.
Reversible plow, 207.
Road drag, 150, 173.
Road grader, 97; elevating,

169; scraping, 168.
Road machinery, 167; classes,

167; scrapers, 167.
Roads, 141; benefits of good,

142; brick, 165; clay, 153;

earth, 147; extent of, 141;

gravel, 154; history of, 14;

requisites of good, 145;

sand, 153; sand-dlay, 153;

scrapers for, 167; stone, 160.
Road rollers, 170.
Road stone, 160; testing, 161.
Rock crushers, 172.
Roller bearings, 191.
Rollers, for roads, horse, 170;

land, 220; power, 171; tan-
dem, 171.
Rope transmission, 323.
Round barns, 449.
Rubber belting, 321.
Run-off, computing, 80.

Safety valve, 381.

Sand, for building, 411.

Sand-clay roads, 153.

Sand roads, 153.

Sanitation, 480.

Scrapers, for disk harrows, 218;

road, 167.
Sections of townships. 39.

Digitized by

Google

INDEX

553

Seeders, end gate, 224; hand,
223; seed-box broadcast, 224;
utility of, 223; wheelbarrow,
224.

Self-aligning bearing, 190.

Septic tank, 501; construction
of. 504.

Sewage disposal, principles of,
502; by irrigation, 114, 138;
systems of, 501.

Shafting, 325.

Shawver bam frame, 446, 448.

Sherringham valve, 534.

Shredders, 256.

Shop, farm, 477.

Side draft, overcoming, 337.

Silos, 461; essentials, 463; lo-
cation, 461; masonry, 468;
size, 461; wood, 465.

Silt basins, 99.

Sled com cutters, 251.

Slings, hay, 271.

Soils, improved by drainage,
61; kinds of, 59.

Splices, 543.

Spraying machinery, 303.

Spraying method of irrigation,
134.

Springs, as water supply, 483.

Spring-tooth harrow, 213.

Stackers, hay, 269; straw, 280.

Stalls, cow, 440; horse, 443.

Standard of purity of air, 531.

State Highway Commission,
178.

Statics defined, 402.

Steam boiler, 376; accessories,
380; capacity of, 379; func-
tions of, 377; management,
388; principle of, 376; tjrpes,
377.

Steam engines, 376, 385; kinds,
386; principle of, 385.

Steam, formation, 377; quality
of, 380.

Steel, Bessemer, 197; cast, 197;
mild, 197; soft center, 198;
tool, 198.

Stone, building, 409.

Stone roads, 160; construction
of, 162; cost of, 165; main-
tenance of, 165.

Stoves, 525.

Strength of materials, 402, 406.

Stress, defined, 403; kinds of,
403.

Subirrigation, 133.

Subsurface packer, 220.

Suction of plows, 200.

Sugar beets under irrigation,
120.

Sulky plows, 201; adjustments
of, 203.

Sunlight as a sanitary agent,
506.

Surface measure, 19.

Survey, defined, 16; prelimi-
nary. 64.

Surveying, agricultural, 16;
divisions of, 17 ; problems, 26.

Surveyor's measure, 20; uses
of, 16.

Sweep rakes, 268.

Tanks, water, 493.

Tapes, 20; care and use of, 22.

Teams, size of, 329.

Tedder, hay, 267.

Telford roads, 160.

Temperature system of ventila-
tion, 534.

Tests, of concrete, 411 ; engines,
316, 36<g; horse, 328.

Threshing machinery, 278.

Tile, blinding, 94; cement, 92;
inspection of, 94; laying, 92;
roots of trees in, 100; select-
ing, 91.

Tile drains, capacity of, 78;
cause of flow in, 78; construc-
tion of, 96; cost of, 101;
depth, 67; digging ditches,
86; distance apart, 68; fllling,
96; outlet of, 98; size of lat-
erals, 84; staking out, 71;
systems of, 69.

Digitized by

Google

664

INDEX

Tongue truck. 338; for harrows,
218.

Tool, defined. 186.

Tool shop, 477.

Topographical signs, 31.

Towers, water, 493; windmill,
342.

Township, division and num-
bering, 38; sections of, 39.

Traces, proper angle of, 331.

Tracks, hay. 272.

Tractor, steam, 389.

Transit, 54.

Transmission of power, 320.

Transportation, cost of, 142.

Transport truck, 219.

Trapezium, area of, 35.

Trapezoid, area of, 35.

Triangles, area of, 34; trans-
mission of power by, 324.

Trucks, transport, 219.

Turning point, 52.

Ultimate strength of materials,

404.
Underdrainage, 59.
United States system of land

survey, 38.

Valve action in oil engines, 359.
Valves, for pumps, 489; safety,

381.
Ventilation of farm buildings,

531; influence of wind, 533;

mechanical, 535; purpose ji of,

31; temperature system, 534.
Ventilator, cloth curtain, 533.
Vertical boiler, 377.

Wages, influence of farm ma-
chinery on, 182.

Warm-air furnace, 526.

Waste bank, 104.

Water, capillary, 57; control of.
Ill; duty of. 56; hydrostatic,
57; measurement of, 134; reg-
ulation of soil water, 56; re-
quired for crops, 115; used in
irrigation, 117.

Water level. 43; laying tile by,
89.

Water pipe, 491; flow of water
in, 491; sizes, 491; systems,
492.

Water supply, 480.

Water wheels, 487.

Weigher, 280.

Weir, 134.

Wells, 480.

Whipping a rope, 541.

Windmills, 339; construction,
341; development, 339; power
of, 341; regulation, 341; size
of, 340; towers, 342; types of,
340; utility of. 339, 486.

Windows, 'design of, 508; loca-
tion of. 507; size of, 508.

Wing Joist bam frame, 446.

Wire rope transmission, 324.

Wood, as a material for ma-
chines, 195.
Work, defined, 186, 314.
Working stress, defined, 404.
Wrought iron, 197.
Wye level, 46.

Digitized by

Google

Agricultural Text Books

FOR

HIGH SCHOOLS

WEBB PUBLISHING CO.. St. Paul. Minn.

This series of agricultural books, of which Beginning in Animal
Husbandry is a representative, is planned especially for hi^ schools in
which agnculture is taught. The books constitute a complete four-year
graded course in agriculture. Each book is complete in itself, and
Its scope is well within the limits of the course. They are written by
men eminent in their line, and who are well known for their clear and
concise presentation of facts. ^ Each of the books listed below has
suggestive subjects for discussion and demonstration at the close of
each chapter. The series constitutes a complete, concise, and practical
course that will meet the urgent needs of the modem agricultural hi^
schools and of short courses in schools and colleges.
f

FIELD CROPS

A. D. WILSON,

Superintendent of Farmers' Institutes and Extenmon,

Minnesota College of Agriculture,

and

C. W. WARBURTON,

Agr(momist, U. S. Department of Agriculture.

544 pages, 162 illustrations, cloth, $1.50 net.

The aim of this book is to present the peculiarities of each of the
various classes and varieties of farm crops, the handling of the soil,
selections of seed, and general crop management. The book covers the
cereals, includiog com, wheat, oats, rye, barley, etc.; forage crops, in-
cluding hay grasses, clover, alfalfa, cowpeas and other legumes; how to
make good meadows and pasture^, and the art of hay making, etc.; root
crops; sugar crops; fiber crops, including cotton, flax, hemp; tobacco,
potatoes, in fact every farm crop of anv unportance is discussed. The
mtroductory chapters are devoted to the general classification of farm
crops and their uses and relative importance, and reviews the subject
of how plants grow. The concluding chapters discuss the theory and
practice of crop rotation and weeds and their eradication. A hst of
the best supplementary reading, including farmers bulletins, is given at
the close of each cnapter. The style is easy, subject mattex wel^
arranged and vital, and the book is of excellent mechanical ntakr
up throughout.

Digitized by

Google

BEGINNINGS IN ANIMAL HUSBANDRY

By CHARLES S. PLUMB, Professor of Animal Husbandry, Ck)Uege
of Agriculture, Ohio State University.

895 pages. 217 illustratioiu, cloth, $1.25 net.

Beginning^ in Animal Husbandry is the only book published that
is specially designed to meet the needs of students in Animal Husbandry
courses in secondary schools. Among the subjects discussed are: The
Importance of Ammal Husbandry: Breeds of Horses, Cattle, Sheep
and Swine; Animal Type and Its Importance; Reasons and Methods
in Judgine Live Stock; Points of the Horse; Judging Horses, Cattle,
Sheep and Swine, etc.; Heredity: Its Meaning and Influence; Selection
and Its Importance; Pedigrees and Their Values; Suggestions to Young
Breeders; Composition of Plants and Animals; Influence of Foods on
the Body; Feeding Standards, Origin and Use; How to Calculate a
Ration; Coarse Feeds and Their Values; Concentrated Feeds and Their
Value; Care of Farm Animab; Poultry: Types and Breeds. Judging,
Feeding: Eggs and Incubation; Poultry Houses. Topics tor discus-
sion and suggestions for observation and application are included at
the close oi each chapter.

SOILS AND SOIL FERTILITY

TSOJ
WALSTER,

By A. R^ WHITOON, Professor of Soils and Drainage, and H.
If Instructor in Soils, of the University of

Wisconsin.

315 pages, well illustrated, cloth, $1.25 net.

No Other book on Soils presents the relation of the soil to the
production of crops in so clear and agreeable a manner as this. There
are chapters on the following: Conditions Essential to Plant Growth,
Origin and Classification* of Soils; Prinaary Relations of Soil and Plant;
Nitrogen; Phosphorus and Potash; Soil Analysis; Farm Manure; Com-
mercial Fertilizers; Physical Properties of Soils; Water Supply; Tem-
perature and Ventilation of Soils; Drainage; Erosion; Tillage; Humus;
Relation of Crops to Climate and Soil; Soils of the United States;
Management of Important Types of Soil; Dry Farmmg. Ejqplicit
lan^age and the avoidance of technical matter iniak'e the book ideal for
b^inners in this subject. A well-chosen set of fundamental labora-
tory exercises and demonstrations, with complete directions, is included.

POPULAR FRUIT GROWING

By SAMUEL B. GREEN, late Professor of Horticulture and Forestry,
University of Minnesota.

300 pages, 120 illustrations, cloth, $1.00 postpaid.

This book covers the factors of successful Fruit Growing, with
lists of fruits adapted to each state; Orchard Protection; Lijurious
Insects and Diseases; Spraying; Harvesting and Marketing Methods;
Propagation of Fruits; etc. A very popular book for schools and col-
leges. A new, revised edition by Le Roy Cady, Professor of Horticul-
ture, University of Minnesota, is just out.

Digitized by

Google

VEGETABLE GARDENING

By SAMUEL B. GREEN^ late Professor of Horticulture and Forestry,
University of Minnesota.

252 pages, profusely illustrated, cloth, $1.00,

A manual on the growing of vegetables for home use and for the
market. The immense sale of this book to farmers and gardeners, and
its wide adoption for class-room work in agricultural schools and col-
leges, prove it to be the standard work published on this subject. This
is the 12th revised edition. We have a paper covered edition of this
book which sells for 50c.

DAIRY LABORATORY GUIDE

By G. L. MARTIN, Professor of Dairying, North Dakota Agricultural

College.

140 pages, illustrated, cloth, 50c.

This laboratory manual offers a carefully organized series of exer-
cises covering the principles of modem dairy tlractice, with sugges-
tions for their practical appUcation. It covers the Production and Care,
Testing, Manufacture, and Marketing, of Dairy Products. An indis-
pensable guide for classes in Dairying and for Creamerymen.

SILOS: CONSTRUCTION AND SERVICE

By M. L. KING, formerly Silo Expert, Iowa State College, and Orig-
inator of the Iowa Silo.

100 pages, well illustrated, cloth, 50o.

There is no recent American book on silo building, and none of
any date that covers the many types of silos now in use and gives
details of their construction. Mr. King here presents to the intended
builder the principles of silo construction, and the advantages and dis-
advantages of each type; but more particularly he gives the actual
method of construction, with the main points of silo management.

RULES OF ORDER FOR EVERY DAY USE

AND CIVIL GOVERNMENT MADE PLAIN

By HENRY SLADE GOFF, Author of the Goff'a. Historical Maps.

113 pages, illustrated, cloth, 50o.,

There has long been a demand for an accurate Rules of Order text
that was brief yet sufficientl^r complete for all practical needs. This
is such a book. The matter is so clear, so well arranged, and so suc-
cinct that those interested in social centers, clubs, societies, etc., will
be delighted with it. The book also presents the main points of civil
goverxunent that everyone ought to loiow.

Digitized by

Google

OTHER STANDARD AGRICULTURAL BOOKS

AGRICULTURE FOR YOUNG FOLKS

By A. D. WILSON and E. W. WILSON.

A thoroughly practical treatise on Elementary Agriculture dealing
with the every-day problems of the farm.

This book avoids the vague generaUties and scientific theories
and treats each subject in a manner easily imderstood and readily
applied to existing conditions on every farm. Prepared especially for
beginners and contains many valuable suggestions which would prove
interesting to the most experienced farm manager. Among the numer-
ous subjects discussed are: Preparing the Soil; Seeding; Rotation;
Care of Crops; Marketing; Farm Business; Management of Cattle;
Roads; etc., etc. Over 300 pages profusely illustrated. Price, $1.00
postpaid.

AMATEUR FRUIT GROWING, bv Samuel B. Green. A
practical ^de to the growing of fruit for home use and the market,
written with special reference to cold climates. Illustrated. 134 pp.
Price, 12 mo. paper, 25 cents; cloth, 50 cents.

ELEMENTS OF AGRICULTURE, by H. J. Shepperd aad J. C.
McDowell : A complete treatise on practical agriculture, covering plant
and animal breeding; thoroughly illustrated. A complete text book,
adopted in pubUc and agricultural schools throughout the Northwest.
12 mo., cloth, 100 pp. Price, $1.00.

WEEDS AND HOW TO ERADICATE THEM, by Thomas
Shaw, giving the names of the most troublesome weed pests east and
west and successful methods of destroying them. Price, 16 mo., 210
pp., cloth, 50 cents; paper, 25 cents.

FARM BLACKSMITHING. A complete treatise on black-
smithing by J. M. Drew. Written for farmers who want a workshop
where they can profitably spend stormy days. Illustrated, 100 pp.
Price, 12 mo., cloth, 50 cents.

STANDARD BLACKSMITHING, HORSESHOEING AND
WAGON MAKING, by J. G. Hohnstrom, author of "Modem Black-
smithing, " gives practical instructions by a successful blacksmith. The
latest and most complete book on the subject published. Thoroughly
illustrated. Price, 12 mo., cloth, $1.00.

GRASSES AND HOW TO GROW THEM, by Thomas Shaw.
Discusses the economic grasses fo the United States and Canada from
the standpoint of the farmer and the stockmen. Price, 450 pages, cloth,
$1.50 postpaid.

I WEBB PUBLISHING CO. ST. PAUL, MINNH

Digitized by

Google

Digitized byVjOOQlC

Digitized by

Google

Digitized byVjOOQlC

THIS BOOK ON Tl" J^TS ON THE FOURTH
WIIO. INCREASE TO^O«^^^ ^^^^ OAY
DAY AND TO ft-OO on
OVERDUE.

U) 21-100m-8,'34

Digitized by

Google

^'B 10114

*-if|f:r.g|JfDigitized bydOOQlC

Digitized by

Google

Internet Archive Audio

Featured

Top

Images

Featured

Top

Software

Featured

Top

Books

Featured

Top

Video

Featured

Top

Mobile Apps

Browser Extensions

Archive-It Subscription

Save Page Now

Full text of "Agricultural engineering; a text book for students of secondary schools of agriculture, colleges offering a general course in the subject and the general reader,"

See other formats