CONCRETE SILOS

Their Advantages
Different Types
How to Build Them

By
E. S. H,ANSON

Affiliated Member Western Society of Engineers, Editor THE

CEMENT ERA. Author "Cement Pipe and Tile," "Concrete

Roads and Pavements," Etc.

CHICAGO

THE CEMENT ERA PUBLISHING COMPANY
1916

Copyright 1915
By The Cement Era Publishing Company

PREFACE.

In this volume the author has attempted to bring
together everything of value pertaining to the latest
concrete silo construction. His investigation of the
subject has led him to believe that there is a demand
for such a book. While there is a large mass of
literature on concrete silos extant, practically every
piece of such printed matter is prepared with special
emphasis on some particular type of construction, or on
some particular phase of the subject.

This volume is an attempt to bring together all the
best things in this scattered literature, making it, so
far as possible, a complete compendium of concrete silo
construction. For this purpose the author has drawn
freely upon bulletins of the various cement companies
and of the Association of American Portland Cement
Manufacturers, as well as upon publications of the
State Agricultural Experimental Stations, and the
literature of the companies promoting various patented
systems.

The demand for the book, even before it has
appeared from the press, has been so gratifying that it
is expected another edition will be necessary at an
early date. The author will therefore be pleased to
have readers advise him of any errors, inaccuracies, or
omissions which they find.

E. S. HANSON.
Chicago, Oct. 15, 1915.

365551

CONTENTS

Page

Chapter I. Why Build a Silo 5

" II. What a Good Silo Should Be 25

11 III. How Concrete Meets the Eequirements 30

" IV. Advantage Over Other Kinds of Silos 37

1 ' V. Size and Shape of a Silo 49

11 VI. The Different Types of Concrete Silos 56

' ' VII. The Foundation of the Silo 59

11 VIII. The Monolithic Silo 63

< ' IX. The Polk System 73

' ' X. The Monsco System 79

" XI. The Eeichert System 84

' ' XII. Other Monolithic Systems 89

" XIII. The Pit Silo 97

XIV. The Metal Lath Silo 102

" XV. The Concrete Stave Silo 125

XVI. The Concrete Block Silo 140

' ' XVII. Doorways, Doors, Eoofs, etc 157

' ' XVIII. How to Increase the Silo Business 165

Catalog Section 175

Concrete Silos

CHAPTER I

WHY BUILD A SILO ?

The silo is not a fad. It has proven its right to a
place in any intelligent scheme of agricultural econom-
ics, and it has therefore come to stay.

Coming first into existence as a mere hole in the
ground, the silo has developed into a structure on which
it is worth while to expend engineering ability and
architectural skill. Many things have been attributed
to Caesar and his strategists as the result of military
necessity in the prosecution of his famous campaigns.
Some of these are recorded in his own Commentaries,
while others have perhaps a less stable historical foun-
dation on which to rest. Our reading of the Seven
Books is too far in the past to allow of a definite state-
ment as to whether the famous general himself records
the use of pit silos for the preservation of forage along
his lines of march; but such have been attributed to
him, and the statement sounds plausible, at any rate.

The silo has been likened to a giant fruit jar. Ap-
parently this idea, too, is not a new one, for it is stated
that the early Egyptians, many years before the Chris-
tian era, put a part of their crops in large stone jars
for preservation, covering them as tightly as possible
to exclude the air. The Mound Builders and other

(5)

6%' -Concrete Silos

(prehistoric tribes adopted similar expedients, as is
proven by the relics which are unearthed from time to
time, while some of the barbaric tribes of the present
day build circular bins of interwoven reeds and plaster
them on both sides with clay, with a thatched roof for
a cover.

The following reasons for the popularity of silage
are given by T. E. Woodward, of the Dairy Division
of the U. S. Department of Agriculture :

(1) Silage is the best and cheapest form in which
a succulent feed can be provided for winter use.

(2) An acre of corn can be placed in the silo at a
cost not exceeding that of shocking, husking, grind-
ing and shredding.

(3) Crops can be put into the silo during weather
that could not be utilized in making hay or curing fod-
der; in some localities this is an important considera-
tion.

(4) A given amount of corn in the form of silage
will produce more milk than the same amount when
shocked and dried.

(5) There is less waste in feeding silage than in
feeding fodder. Good silage properly fed is all con-
sumed.

(6) Silage is very palatable.

(7) Silage, like other succulent feeds, has a bene-
ficial effect upon the digestive organs.

(8) More stock can be kept on a given area of
land when silage is the basis of the ration.

(9) On account of the smaller cost for labor, silage
can be used for supplementing pastures more econom-
ically than can soiling crops, unless only a small
amount of supplementary feed is required.

(10) Converting the corn crop into silage clears
the land and leaves it ready for another crop sooner
than if the corn is shocked and husked.

Concrete Silos 7

Another and even longer list of advantages of en-
silage is given by the experts of the Missouri Agricul-
tural Experiment Station. They are as follows :

(1) Harvesting corn as silage saves from 35 to 40
per cent of the crop that would otherwise be wasted.

(2) Silage adds palatableness to the ration.

(3) Silage adds succulency to the ration.

(4) Silage serves to keep the digestive tracts of
animals in good condition.

(5) Silage replaces high-priced hay.

(6) Silage serves to cheapen the ration.

(7) When silage is fed, more feed is eaten, hence
more manure.

(8) The man who feeds silage uses a manure
spreader.

(9) The feeding of silage means more intelligence
in feeding operations.

(10) The feeding of silage results in more intelli-
gence in other farm operations.

(11) The man who feeds silage will feed with it
concentrates rich in protein, and leguminous hay of
some kind. Hence, not only more manure, but a bet-
ter quality.

(12) The man who feeds concentrates and legu-
minous hays with silage is apt to try to grow legumes
in the rotation. Hence, a better and more productive
soil.

(13) Silage is a good feed for the general farmer.

(14) Silage is a good feed for dairy cows.

(15) Beef can be produced more economically
when silage forms a part of the ration.

(16) Silage is a good feed for calves and stocker
cattle.

(17) Silage is a good feed for breeding cattle.

(18) Silage is a good feed for fattening lambs.

(19) Silage is a good feed as a part ration for
brood ewes if fed intelligently.

(20) Silage can be fed successfully as a part ration
to mules.

8 Concrete Silos

(21) Silage can be fed successfully as a part ra-
tion for horses.

(22) Silage may be fed as a conditioner to swine
in general, and as a part ration to old brood sows.

(23) Silage mixed with wheat and potatoes, equal
parts, and boiled in water makes a good ration for
poultry.

(24) Silage takes up less room in storage than
either hay or corn fodder.

As to the kind of crops which can be preserved in
the silo to advantage, it has been stated that anything
which does not have a hollow stem will make good
silage. This statement has a reasonable measure of
truth. The reason that crops with hollow stems have
been excluded is, that it is impossible to get the air
pressed out of the stems, and on account of the pres-
ence of this air, decomposition is sure to take place.

The fact remains, however, that corn is pre-emi-
nently the crop for the silo. As stated by Prof. C. H.
Eckles, of the Missouri Experiment Station, and borne
out by the statements of many other authorities, the
total yield of nutrients per acre with this crop is greater
than ordinarily secured from any other. It has the
further advantage of packing well to exclude the air,
and contains the proper amount of sugar to form acids
needed to preserve without becoming sour.

An a/ere of corn as silage requires much less room
for storage than an acre of corn harvested in any other
way. When the harvesting is done the work is mainly
over. The field is left clear for any fall sowing. Drilled
corn yielding 75 bushels to the acre, when cut and
shocked, eleven shocks to the -acre, covers about 3 per
cent of the area of the field. The shocks remain in the
way of the next crop. Before the corn is husked out,
bad, rainy, snowy weather often comes. The stalks,

Concrete Silos

Two of the Four Silos on the Dairy Farm of Thomas A. Edison,
at Stewartsville, N. J.

blades and shuck become so damaged from the weather
that they are not worth much as a feed, even if they
were always fed in a dry, clean place where stock
could not tramp them into the ground in wet, muddy
weather. The process of husking, throwing the corn
011 the ground, pitching it into a wagon and out again,
and then out of the crib into the same wagon before
it can be fed, is not only an expensive one, making the
farm labor problem still harder to solve, but it is a
wasteful one. Much corn damages from the weather,

10 Concrete Silos

from rats and mice and from shelling in handling so
many times.

It costs on an average about 12% cents to put corn
into the shock and about 12% cents to shuck it out.
The stover (stalk without the ear), sells on the average
for about 12% cents a shock. This is an expensive
operation, even when it is the last resort, but on some
farms it is a common practice.

However, when a man has no silo in which to har-
vest corn and his crop rotation is such that corn is to
be followed by wheat, or some other fall sowing, about
the only thing he can do is to cut the corn and put it
into the shock. This is especially true if a man is a
grain farmer and cannot forage the corn off.

Again it may be stated that while silage can be fed
to practically all farm animals to good advantage, it is
pre-eminently the ideal ration for cattle, and especially
the dairy cow. It thus forms an important link in
connecting up one of our largest farm crops with the
wide-spread and important industry of cattle raising
and dairying.

The digestive organs of animals that chew the cud
are so formed as to require comparatively juicy and
bulky food. The cow cannot, therefore, thrive on ex-
clusively dry food so well as can the horse. The near-
est an ideal food that can be obtained for the dairy
cow is good pasture; but for more than six months in
the year green pasture is not available in large sec-
tions of this country. The best substitutes to use dur-
ing this period are corn silage and such roots as man-
gels and turnips. Corn yields an average of twice as
much dry matter per acre as do root crops, and, since
the latter require much more labor, which in this

Concrete Silos 11

country is relatively expensive, silage is far more
economical.

The dairy cow has been likened unto a factory — a
factory for the production of milk and butter. She
eats her feed, converts it into blood and from the blood
which passes through the mammary gland or udder,
she extracts the milk. The output of this factory, like
that of any other factory, depends much upon the
amount and quality of raw material consumed. No
cow can produce a large quantity of milk and butter
unless she has the capacity and consumes a large quan-
tity of good feed. Since it is impossible to feed fat
into milk or change the .average per cent of butter fat
in a cow's milk by the kind, amount or quality of feed,
the thing for us to do is to feed her in such a way as
to enable her to produce the maximum amount of milk.
From more milk we can get more butter fat.

In order to get a cow to consume large quantities
of feed, the feed must be good and palatable. Pala-
tableness means much. Every feeder of live stock of
any kind recognizes the importance of keeping the ap-
petites of animals good.

During the process of fermentation of silage in the
silo, the corn plant is rendered more digestible and
more palatable than dry shock corn, and a flavor very
acceptable to dairy cows is produced. After cows have
been fed silage, they will stretch out their backs and
turn their heads in the direction of the feeder the min-
ute he starts toward them with a box of silage. So
well do eows relish silage, they will eat more of it
than they do of dry fodder or even of green corn. This
is a point in favor of silage, because every cow must
eat so much feed for the daily maintenance of her
body. After this maintenance requirement is met, all

12 Concrete Silos

excess food can be used for the production of milk and
butter. However, some cows do not make use of this
excess food in this way. They use it for surplus fat
and flesh, thereby gaining in weight. The chief dif-
ference between dairy cows is shown in the difference
in the disposition that they make of their food over
and above that required for maintenance. Now, if
every cow would absolutely refuse to produce a drop
of milk until after her daily body maintenance require-
ments were met, some of us would learn a little faster
how to feed for milk production. But not every, or
even any cow, makes this demand. There are three
classes of cows when both cows and the feed they are
given are considered :

Class 1. Cows that receive more than a maintenance
ration and use the excess for the production of milk
and butter.

Class 2. Cows that receive more than a maintenance
ration and use the excess for the production of surplus
flesh and fat, storing it away on their bodies, growing
heavier every day.

Class 3. Cows that receive less than a maintenance
ration and have to draw upon the food nutrients al-
ready stored on their bodies in order to keep up a flow
of milk, thus growing thinner and thinner in flesh every
day.

This third or last named class is seldom found in
the herd of the man who feeds silage. He feeds as a
rule an abundance of palatable, succulent silage in
combination with other feeds richer in protein content.
The protein in the ration goes to make bone, muscle
and the curd in the milk.

Silage is a roughage. Rurrniants require a greater
per cent of roughage in the rat m than do other classes

Concrete Silos 13

of animals. Corn silage comes the nearest to having
all of the properties of good green grass of any of the
feeds we have. We can have it in the winter time, too,
when grass is gone and other feeds are dry. "We can
have it in the summer time when the grass is short in
dry periods of drought. Silage, above all other feeds,
enables the dairyman to maintain almost unbroken
summer conditions, conditions under which the maxi-
mum amount of milk and butter is produced.

A feed containing a large amount of water in the
form of natural plant juices is not only more easily
digested, but is also more palatable and, besides, serves
the useful purpose of keeping the whole system of the
animal in good condition. A silage-fed animal is rarely
troubled with constipation or other digestive disturb-
ances, the coat is noticeably sleek and soft, and the
skin is soft and pliable.

No rough feed is more palatable than good corn
silage. Sometimes, however, a cow will not eat silage
readily until she has (acquired a taste for it; this may
require several days. But silage is not peculiar in this
respect, for it has been observed that range horses or
cattle shipped into the corn belt refuse corn the first
time it is offered to them. The quality of palatability
is of great importance, as it induces a large consump-
tion and stimulates the secretion of digestive juices.

The advantage of silage in the dairy industry was
at one time put into a forcible statement by W. B.
Barney, state dairy commissioner of Iowa. Among
other things he said:

The dairy cow is the most economical producer of
human food on the farm if fed and cared for in an in-
telligent manner. The milk of a cow that produces
10,000 pounds yearly contains 8,710 pounds of water,

14 Concrete Silos

290 pounds of fat, 485 pounds of sugar, 340 pounds
of protein and 75 pounds of ash. Therefore, it is evi-
dent that the cow must consume large quantities of
succulent feed to produce milk economically. The
grass in summer provides her with such feed, but if
the farmer is without a silo his cows are deprived of
succulent feed for winter use. No man keeping six or
more cows can afford to be without a silo, regardless of
its first cost.

Today the silo is no longer an experiment, and prac-
tically all the leading dairymen of the country are
using them. Some seven or eight thousand new silos
have been built in Iowa alone during the past year,
which is sufficient evidence that they are a success.
We are not suffering today in the rural districts for
the want of finding new things so much as we are for
the simple application of the things we already know.
Practically every farmer admits that the silo is a good
thing, but he puts off until tomorrow what he should
do today, and the waste of crop continues from year
to year. In the corn belt where stalks are allowed to
stand in the field, 40 per cent of the crop is wasted.
It has been estimated that an acre of corn put up in a
silo has a value of $45, while the same standing in the
field and husked has a value of $27. Thus it can be
seen that the silo nearly doubles the value of the corn
crop.

In feeding silage with alfalfa or clover hay we
have practically a balanced ration all raised on the
farm. Experiments have been conducted at the Kan-
sas and other stations which show that the grain ra-
tion can be cut down one-half the usual amount where
alfalfa or clover hay and silage are fed. Silage always
plays a prominent part in the economical ration of most
farm animals, and may the day be not far distant
when the silo will be as common a sight on the Iowa
farm as the corn crib is today.

In the Central West corn is hailed as the king of
all cereals, forming the backbone of the rations of the
majority of our farm animals. By placing corn in the

Concrete Silos 15

silo the stalk as well as the ear is preserved, thus mak-
ing the whole corn plant available for feeding pur-
poses. Practically 40 per cent of the feeding value of
the corn plant lies in the stalk, leaves and husks, the
remainder in the ear. Therefore, if only the ears are
gathered, much of the remaining 40 per cent of the
crop remains in the field to bother the farmer in pre-
paring his seedbed for the following year. As corn
should be cut for the silo before the lower leaves are
lost there is practically no waste. About twice the
amount of dry matter can be stored in the form of
silage as corn fodder. A cubic foot of hay in the mow
contains about 4.3 pounds of dry matter, while a cubic
foot of silage contains 8.9 pounds of dry matter. A
cubic foot of space in the silo is, therefore, worth more
than twice an equal space in the mow.

The digestive organs of animals that chew their
cud are so formed as to require comparatively juicy
and bulky feeds. The cow cannot thrive on dry feed
as well as the horse. The ideal food for the dairy cow
is green pasture, but for a number of months during
the year she is deprived of this feed. The best sub-
stitutions for green pasture are root crops and corn
silage. As silage yields twice as much dry matter per
acre as roots and does not require as much labor, silage
is by far the more economical wherever corn can be
raised. Silage has a laxative effect upon the animal
and aids in maintaining a healthy and vigorous condi-
tion.

The population of the United States is doubling
every thirty years, which means that the farms will
gradually become smaller and that more feed must be
produced per acre. The high price of land also de-
mands that more intensive methods must be used to
obtain a dividend in proportion to the value of the soil.
Practice tells us that one acre of corn placed in the
silo will yield enough feed to supply a milk cow 40
pounds of silage for 500 days or 4 cows 125 days.

Another important factor is the reduction in stor-
age space of silage compared to that required for hay.

16 Concrete Silos

One ton of clover hay occupies 400 cubic feet, while 8
tons of silage can be placed in the same space. The
clover hay contains 886 pounds of digestible nutrients,
while the silage contains 2,064 pounds. Thus the corn
silage occupying the same space as the clover hay con-
tains two and a half times the digestible nutrients.

Silage as a milk producer compares very favorably
with the other more concentrated and more expensive
feeds. Being a very succulent and palatable feed, it
can be very aptly termed the great substitute for pas-
ture in the corn belt. We all look forward to the in-
creased milk flow when the cows iare turned to pasture
in the spring after having received nothing but dry
feed, for six months. The milk cow is a sensitive ani-
mal at hard work and should be nurtured on the best
feed possible. Silage makes possible a succulent feed
for winter use, spurring the appetite of the cow and
causing her to relish her feed in winter as well as
summer.

Several years ago at the Ohio Experiment Station
the substitution of silage for grain in the ration proved
very successful. Silage was used to take the place of
over half the grain ration and proved to be much
cheaper. The silage ration produced milk for 68 cents
per 100 pounds and butter fat at the rate of 13 cents per
pound. The grain ration produced milk at $1.05 per
100 pounds and butter fat for 22 cents per pound. This
made the profit from the silage ration $5.86 per month,
and of the grain ration $2.46 per month.

There is an occasional suggestion that milk from
silage fed cows has a disagreeable flavor. In order to
determine what foundation, if any, there was for this
belief, a series of experiments was sometime ago un-
dertaken by the Agricultural Experimental Station of
the University of Illinois.

For the purpose of these experiments, the Univer-
sity dairy herd was divided into two lots, one of which
was fed 40 pounds of corn silage per cow per day, to-

Concrete Silos 17

gether with a small amount of clover hay and grain.
The feed for the other lot consisted entirely of clover
hay and grain. The milk from both the lots was cared
for in exactly the same manner and was standardized
to 4 per cent of butter fat in order that there might
be no difference in the flavor of the two lots of milk on
account of the variation in this respect.

The people whose tastes were consulted with re-
gard to the milk were divided into three classes : ladies,
men of the faculty, and students.

In one case the silage had been fed one hour before
milking. Of the 29 ladies who sampled this milk, 10
preferred the silage milk, 14 the non-silage, and 5 had
no choice. Of the men of the faculty, 27 preferred the
silage milk, 20 the non-silage, and 7 had no choice. Of
the students, 20 preferred the silage milk, 4 non-silage,
and 4 had no choice.

A preference for silage milk was indicated by 51
per cent of the 111 tests made when silage was fed
one hour before milking. When silage was fed at time
of milking, 71 per cent preferred silage milk, and when
fed after milking 51 per cent reported the same pref-
erence. Of the total tests, amounting to 372 persons,
223 preferred silage milk, 109 non-silage milk and 40
had no choice.

In making an investigation of the entire silo ques-
tion, The Twentieth Century Farmer, of Omaha, says
that it found one man who, although having three silos
on his place, claimed that silage was too expensive a
feed for profitable use, and that he would not recom-
mend other farmers to erect silos. He told the investi-
gator that alfalfa was a much better and cheaper feed
and he believed better results could be obtained by
feeding more alfalfa and less silage. He was discov-

18 Concrete Silos

ered, however, plowing up an alfalfa patch, putting in
some corn, and not feeding any new alfalfa that season.
This resulted in an investigation, which seemed to show
that the man's statements were prompted by selfish
motives, rather than by his real feeling in the oase. It
was found that he had bought up during the winter,
from his neighbors who did not have silos, and were
thus compelled to sell, a lot of calves and young cattle,
feeding them on the silage he had stored in his silos
and making a very nice profit on the deal. If his neigh-
bors were encouraged to build silos the possibility of
his agiain taking advantage of their unfortunate cir-
cumstance would be very slight indeed.

One line of investigation followed by The Twentieth
Century Farmer was to find out whether or not a much
larger percentage of cattle could be maintained on the
farms of the country by the more extended use of the
silo and the feeding of silage year after year. This
question was therefore asked of numerous farmers of
from one to seven or eight years' experience in feeding
silage, what percentage more of cattle could be kept
profitably on their farms if they had sufficient silo room
in which they could be sure to have silage to supple-
ment the pastures in dry periods, and also to have
plenty of this feed for winter time. While none of
them had definite figures they could give, they all had
some ideas based on their feeding experience. The
answers to these questions from probably 50 different
silo users have been that they could keep from 50 to
100 per cent more cattle by the use of the silo than
they could without.

Silage stands first in rank of all the roughages for
•finishing cattle, says T. E. Woodward, of the U. S.
Department of Agriculture. Formerly, during the era

Concrete Silos 19

of cheap corn and other concentrates, little attention
was given to the roughage, as it was usually considered
merely a "filler" and of very little economic value in
feeding. No especial care was taken in selecting any
particular kind, nor was the quality of it seriously con-
sidered. As the prices of the concentrated feedstuffs
advanced, the feeder looked about for methods of
cheapening the cost of producing beef, and soon found
this could be accomplished by using judgment in select-
ing his roughage with respect to the grain fed. This
has continued until at the present time the roughage
receives as much attention as the concentrated feed,
and has been made to take the place of a large amount
of the latter. The feeding of silage oame into general
use with the advent of expensive grain and is becoming
more popular each year. With the present prices of
feedstuffs, there is hardly a ration used for feeding cat-
tle which cannot be cheapened by the use of this suc-
culent feed. By combining it with other feeds, the
efficiency of the ration is increased to such an extent
that the amount of the daily gains is invariably
greater and the cost of producing a pound of gain is
lessened. The heaviest daily gains are usually made
during the first stage of the feeding period, and silage
can then be used to advantage in large quantities with
a small amount of grain, but as the feeding progresses
the amount of silage should be lessened and the grain
increased. In some places the price of hay and stover
is so high that the greater the proportion of silage
used in the ration the more profitable is the feeding.

Silage is a quick finishing roughage in that it pro-
duces large daily gains and produces a glossy coat and
a soft, pliable skin. Moreover, it can be used to advan-

20 • Concrete Silos

tage at times for carrying cattle for & longer time so
as to pass over a period of depression in the market, or
to carry the cattle along in thrifty condition so they
can be finished at a later period.

For many years the belief was general that cattle
which received silage as a major portion of the rough-
age would have to be kept in warm barns and not ex-
posed to the cold. While they do need protection from
the cold winds 'and rains and need a dry place to lie
down, it has been clearly demonstrated that warm
barns are not only unnecessary, but that fattened cat-
tle make both larger and cheaper gains when fed in
the open sheds than when confined in barns.

Silage can be profitably used to supplement the
pastures for steers during a time of drought, when they
are being finished for market.

The general impression that choice or prime car-
casses cannot be made by the use of succulent feed is
equally untrue, as the silage-fed cattle usually make
more desirable caroasses than cattle fed a similar
ration except that silage was replaced by one of the
coarse fodders. There is no appreciable difference in
the percentage of marketable meat that steers will
dress out which have been finished on a silage ration
and »a dry ration. The meat seems equally bright and
the fat as well intermixed with the lean.

A number of the agricultural experiment stations
have conducted experiments at various times to ascer-
tain the value of silage as a rough feed. At the Mis-
souri Station, some experiments were made with two-
year-old fattening steers, under direction of Prof. H.
D. Allison. Without going into the details of this ex-
periment it will be necessary only to give a few para-

Concrete Silos 21

graphs from the summary made by Professor Allison.
He says:

A ton of silage, as used in this experiment, was ap-
proximately equal to one-half ton of clover hay.

Estimated on the basis of net profit per steer, a ton
of dry matter in the form of corn silage yielded 50.3
per cent greater value than a ton of dry matter in the
form of shock corn.

It is evident from the data given that it takes less
grain in the form of shelled corn to fatten two-year-old
steers when corn silage composes a part of the ration.

A superior finish is obtained on fattening cattle
which are marketed in the spring when silage composes
a part of the ration.

A similar experiment at the Iowa station brought
practically the same results. Regarding it, Prof. John
M. Evvard stated that "the silage-fed cattle, without
a single exception, returned greater profit than when
clover was fed as the only roughage. By using silage
the gains in weight were cheapened and the profit per
steer increased."

Some very valuable cattle feeding tests have been
conducted at the Pennsylvania State Experiment Sta-
tion, among them an experiment to determine to what
extent silage could profitably be used in steer feeding.
This experiment lasted 126 days. The results of the
test are given in detail by Prof. W. A. Cochel, in Bulle-
tin No. 118, issued by the Pennsylvania station.

The results of this experiment are interesting at
this point, not only because silage formed a part of the
ration used, but on account of some valuable data de-
rived, showing that during the early part of the feed-
ing period some ear corn or shelled corn can profitably
be replaced by silage.

22 Concrete Silos

In his Bulletin Professor Cochel says: "Experi-
ments at this and other stations have shown that the
addition of corn silage to the rations that are usually
fed to fattening animals, results in 'cheaper and more
rapid gains in the feed lot, and that its succulent nature
causes cattle to shed the hair early and to look more
attractive than those fed exclusively on dry feeds. A
further advantage in Pennsylvania is that an excellent
quality of corn silage can be produced in localities
where the season is too short for corn to mature."

The value of corn silage as a part of the ration in
fattening cattle is also shown from the results of a
feeding test conducted at the Indiana Experiment Sta-
tion. The results of this test are shown by Dean J. H.
Skinner and Prof. F. G. King, in their Bulletin No. 163.
These gentlemen state that:

The addition of corn silage to a ration for fattening
cattle decreased the consumption of shelled corn in
amounts closely approximating the grain content of
the silage consumed by the cattle.

The addition of corn silage once daily to a ration
of shelled corn, cottonseed meal and clover hay, re-
duced the cost of gains $1.83 per hundred pounds and
increased the total profits $11.19 per steer.

The substitution of corn silage for clover hay in
a ration of shelled corn, cottonseed meal and clover
hay reduced the cost of gain $4.35 per hundred pounds
and increased the profits $17.97 per steer.

The more nearly corn silage replaced the clover hay
in the ration the cheaper was the gain and the greater
the profit.

Corn silage produced a very rapid finish on the
cattle.

The Missouri Experiment Station has secured from
a large number of farmers in that state their experi-
ence in the feeding of silage.

Concrete Silos 23

In reply to the following question: "By feeding
silage do you find your feed bill for the year is any
less than when silage is not fed?" 196 correspondents
out of 200 answered, "Yes;" two answered, "I don't
know," and two said, " I can't tell yet." One hundred
and fourteen of these men feed cattle.

Out of 114 replies to the following question: "Do
you find that it requires less grain to fatten a steer
when silage forms a part of the ration?" 112 answered,
"Yes;" one replied, "I do not know," .and one said,
"I have not had enough experience to enable me to
answer this question."

In answer to the question: "Do you find that it
costs less to fatten a steer when silage forms a part
of the ration?" 112 answered, "Yes," two answered,
"I don't know."

The correspondent cattle feeders were also asked
the question: "What per cent has the feeding of silage
lessened the cost of production of beef on your farm ? ' '
Out of 79 replies, there was but one who was willing to
say that there was no decrease in cost ; 17 answered 25
per cent ; 10 answered 33 1-3 per cent ; 12 answered 50
per cent; while other replies were scattered over a
wide range of gain.

A stock raiser writing to The Independent Farmer
has this to say of the feeding of silage :

We consider the silo as necessary as our barns. In
fact, we could not afford to do business on high-priced
land without such economical feed as silage. It enables
us to keep up a heavy milk flow from our cows at a
very low cost. During the past year, in our cow test-
ing association, one of our Holsteins returned us a
profit of $131 over and above her feed, and we sold our
silage to her at $3 per ton. Our entire herd returned
us an average profit of $101.05, over and above their

24 Concrete Silos

feed. This does not include the calf, manure, nor skim
milk. These very gratifying results to us would have
been impossible if we had not had a silo. "We use
silage a great deal to supplement our pasture. In fact,
this coming summer we are going to feed silage and
alfalfa the year around. We feed silage to everything
on our farm. Brood sows especially relish a light feed
each day, and during the suckling period it greatly
stimulates the milk flow. Our hens are considerably
better because of their receiving a liberal ration of
silage. Our brood mares and colts have for their noon-
day meal during the winter about fifteen pounds of
this excellent feed. In fact, we never had our colts
grow better than since we started feeding silage and
alfalfa. For all classes of live stock these two great
feeds go hand in hand.

CHAPTER II

WHAT A GOOD SILO SHOULD BE

Before determining whether any particular type of
silo is good or bad, it is necessary first to decide what
are the requirements which make for efficiency in silo
construction. It is only by applying certain standards
to any article that we can decide on its fitness or un-
fitness for the purpose for which it was intended. It
is therefore essential that everyone who has to do with
silos, including the farmer, the builder, the agricul-
tural engineer and economist, and the promoter of
silo construction, should know how to value a silo to
determine whether it will do the work expected of it
and justify the expenditure of money which it requires.

Let us then set down the principal requirements
for an efficient silo. It should be :

1. Airtight,

2. Moisture proof,

3. Fire proof,

4. Vermin proof,

5. Frost proof,

6. Strong,

7. Durable,

8. Cheap as to maintenance cost,

9. Round in shape,

10. Smooth as to interior walls.

Having thus arbitrarily stated our standards, at

least most of which will be recognized as correct by

anyone who understands the purpose of the silo, it will

nevertheless be worth while to take up each one of

(25)

26 Concrete Silos

these separately and determine the grounds of its
importance.

(1) Airtightness. It is quite customary, as we
have already done in the first chapter of this volume,
to liken a silo to a giant fruit jar. And whether can-
ning is being done in the home or on an extensive com-
mercial soale in a canning factory, it is recognized as
of prime importance that the contents of the can shall
be sealed positively from the air. For this purpose a
material which is absolutely airtight is used — glass in
one instance, and tin in the other — and the seal is made
in one case with a rubber gasket and in the other with
a solder joint. The demand for the exclusion of air
has a perfectly well recognized scientific basis. The
spoiling of fruit or vegetables in a can, or the spoiling
of silage in a silo by rotting, is simply a bacteriological
action and will not take place unless oxygen be pres-
ent to support the organisms which destroy the con-
tents of the receptacle.

(2) Imperviousness to Moisture. It is necessary
that the walls of a silo be impervious, not only to ex-
clude moisture from the outside, which at times might
enter in such quantities as to do considerable damage
to the contents, but also to preclude the possibility of
the natural juices in the silage from being lost. As
previously pointed out, one of the advantages of silage
is the fact that these juices are retained rather than
being allowed to evaporate, as in the case of ordinary
hay. So the silo which approaches closest to the ideal
will be the one which retains the contents in as nearly
its original condition as possible.

(3) Fireproof ness. In addition to the value of the
silo itself, the contents of the silo can perhaps be
taken at a value of about $5.00 per ton as an average

Concrete Silos 27

figure. Assuming that one has a silo 16 feet in diame-
ter and 40 feet high, the contents of this silo when full
will weigh about 180 tons and will thus be worth about
$900. The situation is easily imaginable, however,
where the value of the contents of the silo could
scarcely be estimated in dollars and cents — a situation
where, if it were to be destroyed, the feeding value of
its contents could be replaced only through much
trouble and financial distress. Add to this fact that
other consideration which is too lightly recognized,
namely, that a fire on a farm is one of the most hope-
less things in the world, placing everything in its wake
practically at its mercy until its ravages are exhausted,
and it is easy to understand why fireproofness is placed
as one of the essentials of the ideal silo. A report of
the fire marshal of Iowa shows that 480 barns were
destroyed by fire in that state in a single year.

(4) Exclusion of Vermin. Not taking into consid-
eration the destruction of the silage which may be ac-
complished by rats and other pests, it is necessary, in
order to maintain the qualities enumerated under head-
ings 1 and 2 above, that the construction of a silo be
such as to exclude these animals. The silo cannot ex-
clude air and moisture if it is of such a construction
that rats or other animals can make holes through
which they can run in and out freely.

(5) Exclusion of Frost. This is a consideration
which will be a vital one in some latitudes, while in
other parts of the country, where the winters are less
severe, it is not of such important consideration. It is
well recognized, of course, that frozen silage should not
be fed to animals. The type of construction, therefore,
which can completely exclude the frost, or at least re-

28 Concrete Silos

duce the amount of frozen silage to the minimum, is the
efficient type to build.

(6) Strength. Experiments have shown, as noted
in another chapter of this book, that the bursting pres-
sure on a silo wall is 11 pounds per square foot for each
foot of depth of silage; that is, in a silo built to a
height of 20 feet, the bursting pressure at the bottom
of the silo is 220 pounds per square foot. In addition
to taking care of this inside pressure, the silo must
also be sufficiently strong to withstand storms of vari-
ous kinds. Winds of high velocity and much force are
not uncommon and tare especially prevalent in those
parts of the country where the largest number of
silos is likely to be built; and as climatic disturb-
ances of this kind are more frequent in the spring
and early summer, when the silo is likely to be empty,
it is quite necessary that the silo itself have sufficient
stability to meet these storms without any dependence
upon the contents to weight it down.

(7) Durability. By this term is meant the ability
of the silo to continue in service without -appreciable
impairment during 'a long term of years. The absolute
cost of any structure is not the initial expenditure, but
the cost per year through its period of usefulness. If
for instance, a silo costing $240 has a life of 40 years,
the capital investment is $6.00 per year. On the other
hand, if a silo costing $60'.00 has a life of but 4 years,
the capital investment is $15 per year.

(8) Maintenance. This is a question which must
be considered in close connection with that of dura-
bility. The structure in order to be efficient must not
only entail a reasonable capital investment per year
of life, but must also be as free as possible from main-
tenance cost. A silo which requires considerable time

Concrete Silos . 29

spent upon it each year to maintain it in reasonably
good condition is not as close to the ideal as we should
be able to get. For one thing this maintenance is an
annoyance and an expense, and for another thing it is
likely to be frequently neglected, thus reducing the
preserving power of the silo.

(9) Shape. The cylindrical silo is most econom-
ical of material, easiest to provide with resistance to
working strains, easiest to fill. The absence of corners
makes it practically impossible for air pockets to form
if reasonable care is exercised in filling.

(10) Smoothness of Interior Walls. By having the
interior walls smooth and free from ledges or offsets,
the silage will settle down perfectly, thus effectually
excluding the air and also allowing the largest pos-
sible amount of silage to be placed.

CHAPTER III

How CONCRETE MEETS THE REQUIREMENTS

Having pointed out in Chapter II the standards of
efficiency by which any silo must be judged, it is of
interest to note how completely concrete as a building
material fulfills all these requirements.

Concrete can, in the first place, be made both air-
tight and moisture proof. It is well known that the
composition of concrete can be governed to suit the
particular requirements in any case. If it is desired
to make it impervious to both air and moisture, it is
only necessary to so proportion the various sizes of
aggregates and so regulate the amount of cement that
dense and impervious concrete will result.

If it is desirable to further insure the non-porous
nature of the concrete, it may have added to it some
other ingredient for making it still more dense. There
are >a large number of such products on the market,
perhaps most of which will answer very well the pur-
pose for which they are intended.

The same result can also be attained by giving the
concrete a surface treatment, either of a cement wash
or of some proprietary pore-filling compound. There
are also a number of these on the market, some of
which have a bituminous or asphaltic base and could
be used only on the interior walls, while others have a
pleasing appearance, or are absolutely colorless, and
could be used exteriorly.

It is generally conceded that concrete itself can,
if given proper attention, be made sufficiently dense

(30)

Concrete Silos

31

for all practical purposes; but with the addition of
one or the other of these methods of excluding >air and
moisture, there can be no doubt whatever of the effi-
ciency of concrete for silo construction so far as these
qualities are concerned.

Concrete has proved its fireproof qualities on so
many different occasions, and in so many different situ-
ations, that it is scarcely necessary to go farther than
a mere statement of the case. There are on record

A Silo Which Withstood Fire on Farm of John H. McCoy,
Harrisville, Pa.

instances of a large number of silos which have suc-
cessfully withstood the ravages of fire where all other
surrounding buildings- have been destroyed. In addi-
tion to saving the silo itself, concrete is such a poor
conductor of heat that if silo openings are properly
protected, the contents of the silo will also be saved
in good condition.

Concrete is proof against the .attacks of vermin.
There is no material which offers stronger resistance
to the attacks of rats and other pests than concrete.

Concrete will give as good a protection against

32

Concrete Silos

frosts as any other material. Of course this is a mat-
ter which varies greatly with the latitude, so that
while in some localities frost does not have to be con-
sidered, there are other places where it is almost im-
possible to exclude frost entirely. In these latter locali-
ties it has been found that a double concrete wall with
an air space intervening will reduce the destruction
of silage by frost to a minimum. In fact, it is safe to
say that there is no latitude where corn can be raised
where a silo of this kind, if properly constructed, and
with openings protected, will not keep the silage in
practically perfect condition.

After a Cyclone Near Georgetown, Kentucky, in Which 81 Barns
Were Destroyed in a Single County

Concrete Silos 33

In this connection, it might be well to suggest that
frozen silage, which is often attributed to frost getting
through the walls, is frequently caused by insufficient
protection at the top. The fact that this freezing is
only around the wall does not disprove this statement.
The silage is of course colder next to the wall than it
is in the middle of a silo, and with the loss of heat
from above, the outside ring will naturally freeze first.
As each day's silage is removed, the freezing continues
on down, and the farmer believes that the silage is
frozen for its entire depth. Investigation, however,
would in many cases show that this is not so, but that
it is frozen only >a few inches below the surface.

As to strength, concrete is also subject to the will
of the builder. By the addition of a sufficient amount
of steel, he can build it to withstand any desired
strain.

One of the pre-eminent qualities of concrete is dur-
ability. When once built, and built right, it is prac-
tically indestructible. It is sufficiently heavy to main-
tain its position against winds or other elemental forces,
and it is not 'affected by age, except that as it grows
older, it grows stronger.

The objection has often been raised against cement
that it is affected deleteriously by the acids in the
silage. This contention has never been proven and
there are numberless authoritative statements to the
contrary. It might be pointed out, however, that even
if there, should be a slight eating away of the con-
crete by these acids, such action can effectually be
counteracted -by some asphaltic or bituminous prepara-
tion once every three or four years. If such a coat-
ing as this is considered necessary, this is practically
the only item of maintenance cost which it will be

34 Concrete Silos

found necessary to expend upon the silo other than
perhaps occasional renewing of the roof, unless a con-
crete roof should be put on in the first place. Concrete,
therefore, admirably fulfills the requirements of low
maintenance cost.

One of the manufacturers of concrete silos has gone
to considerable trouble to gather expressions of opin-
ion from the various agricultural colleges regarding
the concrete silo. An expression was especially asked
on the question of the effect of the acid in silage on
concrete, since this is one of the main arguments usixl

Three Concrete Silos in Perfect Condition After a Wind Storm

• — Photo by Courtesy of Sanders Pub. Co., Chicago

by the opponents of concrete silos. Some of these
statements are as follows :

It has been our experience on the college farm, and the experi-
ence of the men for whom we have supervised the construction
of the cement silos, that when properly built they preserve silage
in first-class shape. We have never noticed the effect of the acid
of silage on the walls of a concrete silo. — O. E. KEED, Professor
of Dairy Husbandry, Kansas State Agricultural College, Man-
hattan, Kansas.

I think it has been definitely established that among all types
of silos, the concrete silo is one of the most durable. The action
of the acid in the silage on the durability of the concrete is not
a large factor in any event, and when the silo lining is covered
with a proper glazed coating, this action is practically negligible.
— F. B. MUMFORD, University of Missouri, Columbia.

Concrete Silos 35

0

A silo, if made with impervious walls so as to exclude the air
and retain the moisture, if made so as to be sufficiently rigid and
of sufficient strength to resist the bursting pressure of the silage,
and lastly if smooth on the inside to permit the silage to settle
properly, will keep the silage regardless of the kind of material
used in the construction. Concrete silos can be made to meet all
these requirements. There is abundant evidence of this and in
no case have we found spoiled silage in any silo where these
essentials were incorporated. — J. B. DAVIDSON, Professor of Agri-
cultural Engineering, Iowa State College, Ames.

I have constructed quite a number of concrete silos and have
found that when the concrete silo is constructed properly, it will
preserve the silage in good condition. I have also found that the
acid of silage has very little effect on the concrete. — J. W. RIDG-
WAY, Professor of Dairy Husbandry, Agricultural and Mechani-
cal College of Texas, College Station.

Concrete silos on the whole will keep silage as well as any
other silo. With concrete walls made of properly proportioned and
well mixed cement, sand, gravel, and the inside washed with grout,
one need not fear injury to the walls due to the acids in the silage.
I have examined quite a number of concrete silos and have not
seen a single one where the acids have made any permanent injury
to the walls. It is my opinion that the effect of the acids in silage
on a concrete wall is a minor matter. — C. F. CHASE, Assistant
Professor Agricultural Engineering, North Dakota Agricultural
College.

It is my opinion that concrete silos keep silage as well as
other makes, and that when the concrete of the silo is properly
glazed the acid in the ensilage does not have any injurious effect
upon the concrete. — W. L. FOWLER, Head Department of Ani-
mal Husbandry and Dairying, University of Arkansas, Fayette-
ville.

There is positively no truth in the statement that cement silos
are destroyed by the acids in the silage. These silos have been
in use for about twenty years. A few days ago I was talking to
a gentleman who had just examined a stone silo that was plas-
tered with cement plaster twenty-five years ago and had not been
lepaired since, and it is now in perfect condition. We have seven
of these concrete silos on the college farms that are keeping silage
fully as well, if not better, than our two wooden silos. — A. S.
NEALE, Dairy Husbandry, Kansas State Agricultural College, Man-
hattan, Kansas.

A great many objections are made to concrete as a suitable
material for silo construction. These statements, of course, come
from competing builders, mostly wood stave silo people. Obser-
vations of concrete and wood stave silos standing side by side show
that the freezing is not greater in one than the other. By coat-
ing the concrete walls with a wash of neat cement or tar pitch
they can be made perfectly air, water and acid proof. That
concrete stave silos are a success has been demonstrated beyond

36 Concrete Silos

a doubt by those built, not only in this state, but other states as
well. Silos of this type are known to have been used successfully
for eleven years without the least sign of deterioration or loss
of silage through spoilage. — AGRICULTURAL EXPERIMENTAL STA-
TION, Ft. Collins, Colorado.

Concrete silos have been in use for at least fifteen years in
this state, and are giving excellent satisfaction. There is no
serious effect of the silage acid on the concrete. — F. M. WHITE,
Department of Agricultural Engineering, University of Wisconsin.

Concrete can very readily be made round in shape.
It is the most • plastic material of any with which the
silo builder will have to deal, and can be fitted perfectly
to his requirements in every way.

Concrete can be given absolutely smooth interior
walls. In monolithic silos, the walls will automatically
assume a smooth surface if proper care is used, even
without any surface treatment, while where concrete
units are used, these form an admirable surface on
which to plaster or to apply any smooth surface
coating.

CHAPTER IV

ADVANTAGE OVER OTHER KINDS OF SILOS

In addition to concrete there are five materials
which are sometimes used for the construction of silos
— stone, brick, structural tile, wood and iron.

In every one of these concrete is 'almost invariably
used at some point: for the foundation wall, the floor,
the mortar with which the units are held together, the
surface finish, or the roof. This being the case, it is
coming to be more and more asked, Why, if concrete
is a good material for these parts of a silo, should it
not be used for the entire structure. It would be
worth while thus to do away with the complications
arising from the use of two or more different materials,
if for no other reason.

None of the materials enumerated has any advan-
tages over concrete as a material for silo construction.
Some of them have decided disadvantages, as a careful
study of them will show.

Of all the above materials, stone comes perhaps
nearest to having the high percentage of efficiency of
concrete, so far as most of the requirements are con-
cerned ; and yet, in the face of this, it is the one mate-
rial which has been almost abandoned for silo con-
struction. This is not to be wondered at when one
comes to consider the matter; for it is a slow and
expensive construction, giving no increased benefit for
its increased cost. There are comparatively few farms
which are situated advantageously with respect to a
supply of stone suitable for building purposes; while

(37)

38 Concrete Silos

if such a supply is available, it is a slow process, and
one requiring the employment of expensive skilled
labor, to work this stone into shape and lay it up in the
wall.

Then, too, ordinary building stone at the best will
usually show a greater degree of porosity than good
concrete. It is easy to see why this is so. Concrete is,
to be sure, composed of stone — possibly even a poorer
grade of stone than would be considered fit for ma-
sonry work; but in concrete each particle of stone is
covered with a film of cement, while in stone masonry
there is no such protective coating. But with a scarc-
ity of stone, there is always a probability that one
who wants to build with this material will be satisfied
with Less than the best, thus working into the structure
a material of even greater porosity, and possibly one
also which will disintegrate rapidly under the action
of the elements. Neither will stone give a sufficiently
smooth interior surface, making it necessary to give it
a plaster coat if the best results are to be secured.

Brick is open to the same objection as stone, so far
as porosity is concerned. Tests made at various times
and places have established beyond question the fact
that a well made concrete has a greater density, and
will consequently exclude air and moisture more per-
fectly, than any grade of brick which would be likely
to be used in silo building. Brick is also inexpedient
for this purpose because of the fact that it usually has
to be hauled a considerable distance, >and on top of
this haulage cost is often a freight bill for shipment
by rail from a distant brick yard. In the case of
brick, too, practically all the material has to be hauled
in, the only local material used being a small supply

Concrete Silos

39

of sand for mortar, if such is obtainable, though the
local supply might be of such a quality that, while very
good for concrete work, the bricklayer would not con-
sider it of the right quality for mortar.

One of the great advantages of concrete for any
work on the farm has always been that local materials
could be utilized to a large extent, not only cutting
down the hauling, but, where a good grade of sand
and gravel is found on the owner's own farm, making
the cost of it practically nothing. In this day of the

Forty-Two Acres of Corn Spoiled by the Collapse of This
Clay Tile Silo

study of economics and the demand for efficiency along
all lines, it would indeed be a sad reversion to ineffi-
cient methods for a man to bring in outside materials
at a loss not only of hauling time, but of actual cash,
when lie has suitable materials right at hand.

It is a difficult matter to properly reinforce a brick
silo. The reinforcing can be placed only in the mortar

40

Concrete Silos

joints between the courses, a more difficult operation,
and giving less strength than where the rods are em-
bedded in the concrete, as in the case of monolithic
concrete work, or where they have special grooves
made to receive
them, as in the case
of concrete blocks,
or, again, where they
completely encircle
the silo, as in con-
crete stave construc-
tion. Bricks, too,
present flat surfaces
to each other, having
no bond except the
mortar joint which
connects them, while
concrete blocks made
especially for silo work usually have some device for
interlocking them in both directions, thus making them
stronger to withstand strains either from within or
without. And brick are open to the same objection as
stone in that they do not present a smooth interior
surface.

With slight modifications, the same objections that
have been stated against brick will hold good as
against structural tile. The air space of the structural
tile will to a certain extent atone for its porosity; but
on the other hand it is more expensive than brick and
is even more difficult to secure, as it is made only in
widely separated plants.

In view of the claim of the opponents of concrete
that it will be destroyed by the action of the acids in
silage, it is interesting to note the illustration here re-

This Vitrified Tile Silo Collapsed First

Night After Filling. On Farm of

Neff Wildrick, Colusa, 111.

Concrete Silos

41

produced from an extensive article by one of the expo-
nents of clay products. He calls concrete a "good
form of foundation for a hollow block silo"; but if it
is good enough for the foundation, where the juices
gather and the acids are the strongest, why should he
consider it such a dangerous material for the body of
the structure?

There are perhaps more wood silos sold than any
other kind. One reason for this is that they are cheap,
and another is that they are short lived and have to be
replaced frequently.

Certain qualities that are inherent in the very
nature of the material of which wood stave silos are

A Good Form of Foundation for a Hollow Block Silo.

Illustration Reproduced from "Brick and Clay Record," Showing
Concrete Recommended as Foundation and Floor For a Silo

made of necessity take them out of the class of perma-
nent structures and put them in the class of temporary
expedients. Wood is not an enduring material, espe-
cially when exposed to the weather. The very nature

42 Concrete Silos

of wood is such that it shrinks when dry and swells
when wet. The permanency of a wood stave silo
depends entirely upon its maintaining a constant
rigidity of structure. It consists of staves set on end,
held firmly in place
by hoops. As long
as the hoops remain
tight the structure
will be comparative-
ly rigid and stable.
As soon as the hoops
become loose, it be-
comes in the highest
degree unstable. In
the modern wood
stave silo the staves
are matched and fit-
ted together by
tongue and groove.
The tongue and
groove are from %
to % inch in depth.

The extreme Circum- Effect of Shrinkage of Wood Staves

ference of a silo 16 feet in diameter is about 50 feet. It
would take very little shrinking to reduce this 50 feet
sufficiently to separate a tongue from a groove. Then,
unless some method is adopted for holding the stave
in place, the stave will fall out and the silo be in
imminent danger of collapse. If the hoops become
loose so as to destroy the rigidity of the structure, it
may be worked in any direction by every light wind.
A single half day of hot weather is sometimes
sufficient to shrink the staves on such a silo to such
an extent that every hoop will need to be tightened

Concrete Silos

43

in order to make the structure safe. When the hoops
are so tightened, a single shower of rain will swell
them to such an extent that either the staves will
buckle or the hoops will break. Of course, there can
be nothing permanent about a structure made of
material in which such qualities are inherent. An
illustration printed herewith is made from a photograph
taken on the inside of a silo and shows the effect pro-
duced by shrinking. No one will imagine for a mo-
ment that such a silo would stand erect under a mild
wind. When a silo collapses it is a matter of consider-
able expense to erect it again. No farmer will be satis-
fied with a silo that
requires such con-
stant attention and is
in such constant dan-
ger.

It is reported by
The Twentieth Cen-
tury Farmer that a
wood stave silo was
erected on the state
fair grounds at Lin-
coln, Neb., solely for
exhibition purposes
by a company en-
gaged in promoting
the sale of just such
silos. It may be
taken for granted
that it was erected in
the best way possible,
in strict accordance
with the mechanical principles involved in proper erec

Wood Stave Silo Displaced by Wind
— Photo by Courtesy of Virginia Agr.
Exp. Station

44 Concrete Silos

tion. But one side of the silo was blown in, thus ren-
dering it praetic'ally worthless until it had been
repaired.

During the summer of 1911 thirty-one stave silos
erected in the vicinity of Lincoln, Neb., were inspected.
In the inspection no silo was passed by. They were
taken singly one by one as they were found. Here is
the result of the inspection:

Five had blown clear down once before they had
been built twelve months; one blew clear down twice
before it had been built twelve months ; one blew clear
down three times before it had been built twelve
months; one blew clear down once before it had been
built five years; one blew clear down once before it
had been built nine years; two blew clear down, but
the date of their erection was not ascertained; eight
had been re-erected
once before they
were up twelve
months ; one had been
re-erected twice be-
fore it was up twelve
months ; four were
leaning badly ; one
had been straighten-
ed twice; two had

7 Wood Stave Silo After a Fire

very loose hoops ; one

had broken nearly every hoop more than once; only

six were in good condition.

With such a record as this, it is impossible to classify
wood stave silos as permanent structures, and
this impossibility rests not, as the wood stave silo
men claim, upon failure to observe mechanical prin-
ciples in the erection of them , but upon qualities

Concrete Silos

45

inherent in the very nature of the material itself. Nor
can such a state of affairs be charged to the fact that
these silos were not properly guyed, because no guying
is sufficient to hold such material in place with a proper
degree of rigidity to insure stability.

No wood exposed to the action of the elements is
safe from decay. The rains that beat upon the out-
side of a silo, the change in moisture conditions and in
temperature, the ab-
sorption of moisture
from the enclosed
silage, all help to
hasten the process of
decay.

The Twentieth
Century Farmer also
states that it has on
file a statement from
a representative of a
wood silo company
to the effect that 25
per cent of the ensi-
lage in concrete silos
rots beyond use. The
editor brands this
unhesitatingly as a
false statement. This
paper has made an
extensive investiga-
tion of silos, and in

the course of this investigation, concrete silo after con-
crete silo has been visited. In no case has dissatisfac-
tion with such a silo been found by the user. Such
silos have been in use for a number of years. The

Failure
E.

of Metal
W. Page,

Silo on Farm
Goltry, Okla.

of

46 Concrete Silos

investigators have not been able to find an owner of
a concrete silo who would build a silo from any other
material.

Relative to the action of acids on silos the publication
above quoted says: "It is very glibly stated by the
salesmen of wood stave silos that the acetic acid devel-
oped by the process of fermentation in ensilage corrodes
and e'ats away the concrete wall so as ultimately to
destroy it. This statement at first glance would seem
to have some basis of truth, for the reason that it is a
well-known fact in chemistry that acetic acid will attack
some of the materials of concrete wherever found, and
thereby produce acetates. This fact has been magnified
and has been used by wood silo men to damage the
reputation of concrete silos. But here is another fact:
The amount of acetic acid developed in fermenting
ensilage is so small and is so much diluted that it has
practically no effect whatever upon the concrete. Con-
crete silo after silo has been visited, some of them
having been in use for more than 25 years, and in no
case has the least evidence of the action of acetic acid
upon the silo wall been discovered. The walls are as
smooth and clear and clean after 25 years of service as
they were in the first place.

' ' The greater initial cost of masonry silos is another
argument used against them by the wood silo men.
This argument might be made valid if the wood silo
men would put their price where it might be regarded
as reasonable. This fact, however, must be remem-
bered— that the first year's loss on a wood silo that
blows down during the first year and has to be re-
erected amounts to more than the initial cost of any
masonry silo. The masonry silo, when properly re-

Concrete Silos 47

inforced, is a permanent structure. There are no hoops
to tighten, no danger from blowing down or from fire.
It grows stronger and more stable with each succeeding
season. It is good for generation after generation. In
some places, owing to cost of material, the initial cost
may be a little more than the cost of a wood stave silo,
but in the end it is a more economic structure. "

With reference to the metal silo, it will scarcely be
necessary to do more than quote a paragraph from the
catalogue of one of the companies selling these silos.
It states:

"In the production of silage, certain mild acids are
formed by fermentation, which, if no protection were
afforded, would have a tendency to cause the galvan-
izing to corrode. To provide against this it is advisable
to keep the inside of the silo painted with some elastic,
acid-resisting paint."

In another paragraph the company advises its cus-
tomers to paint the inside of the silo once a year; and
this, too, is a company which is selling silos of "pure
iron" — the kind which is supposed to be proof against
attacks of any kind.

Granting that the acid in silage does have a slight
effect upon concrete, such a wall, with a thickness of
several inches, will certainly be more durable than a
metal wall having a thickness of a small fraction of an
inch.

The table on the following page, which is a com-
pilation of 296 replies to inquiries sent out to Missouri
farmers, will serve to show the difficulties experienced
with silos of various kinds and the kind of silo pre-
ferred, if another should be built.

48

Concrete Silos

TABLE I— RESULT OP INQUIRIES MADE AMONG 296
MISSOURI FARMERS

K.rxd of Silo

No

rt^YYAWr-

FVr r.en»
giv.rxg

s

.re fe r r

E bVA.I >

n.%^

i rv use

V rouble

made

•=, t QV« S j 77

3.-S.

3S

196

£i >c*ve

;?.T?

Blowing down.15

C.5

Frozen s.la^c,8

3 5

CracKed, \

3.

33

CracHed , 2

16 6G

1 1

Concrete bUcK

IJt

Fraxe^s.Uge.l

833

Q^r»e^

e

Fv ocen s>Uge,3

33 33

3

c

Home-made sK««V

mg* 4ar paper

rro»«»v s.lage, 1

1

Rr

From this table it will be seen that the preference
is for the concrete silo if another kind is discarded. Out
of one hundred men having some difficulty with the
stave silo, 38 prefer the concrete if they should build
another silo. Not a man having a concrete silo ex-
pressed a desire for another kind in the event that he
should build another.

CHAPTER V

SIZE AND SHAPE OF A SILO

As has previously been stated, economy and good
construction will dictate that the general shape of the
silo be cylindrical, and there are at the present time
practically no other shapes used.

It is generally understood, too, that in an economic
and well constructed silo certain relations must be
maintained between the diameter and the height. It is
sometimes stated that the depth of the silo should not
be less than twice nor more than three times the
diameter. This rule has, of course, been violated in both
directions, but it is probably a less serious error to go
above this rather than below. In fact, higher silos are
now advocated by some of the best builders, and there
is a tendency in some sections to build silos higher than
formerly.

It is of course recognized that the greater the depth
of silage, the better will it be on account of the pressure
from above forcing out the air and helping to preserve
it. If the height is less than 24 feet, the quality of the
silage will not be of the best. On the other hand, an
excessive height will increase the cost of filling the silo
by making necessary a larger amount of power to ele-
vate the material into it. It will also necessitate a long
climb for the person whose duty it is to get the silage
out.

Within the limits defined, it is an easy matter to
figure out the size of silo required in any given location.
The two dimensions will in general be fixed by two

(49)

50 Concrete Silos

different considerations. The diameter of the silo will
be determined by the size and nature of the herd to be
fed, and the height by the number of feeding days per
year for which it is desired to provide. A common
error in building a silo is to make the diameter too
great for the size of the herd. When once a farmer has
removed the top layer from his silage and has com-
menced to feed from it, the silage should be removed
at the rate of not less than 2 inches in depth per day in
the winter time and 3 inches in the summer time. It
is necessary to establish a limit of this kind in order to
insure that none of the silage shall spoil.

The weight of a cubic foot of silage varies according
to the pressure to which it is subjected, but there are
certain average figures which can be taken as suffi-
ciently accurate. For instance, in a silo 30 feet deep,
a cubic foot of silage will average about 40 pounds in
weight; so by knowing the amount of silage to be fed
daily, it is possible to estimate what the diameter of the
silo should be to permit the removal of a certain num-
ber of inches in depth each day.

Table II, which is taken from Bulletin No. 21 of the
Association of American Portland Cement M'anufactur-
ers, shows the approximate minimum pounds to be fed
daily from the various diameters of silos. This is based
on winter feeding, and for summer feeding would, of
course, be about 50 per cent more, in order to keep the
silage in good condition. This table also shows the
number of animals which can be fed from each silo on
the amount taken 'away daily at a stated ration for
each kind of animal. Of course, many feeders will not
make out their rations according to this table ; but with
the help of the table, and substituting their own weight

Concrete Silos

51

of rations for the ones used in the table, they can de-
termine very accurately what size herd they can raise
on any diameter of silo, or conversely, they can deter-
mine the size of silo necessary for any given herd.
Multiplying the depth taken away each day by the
number of days which they desire to feed, they will be
able to get the height of silo necessary. The usual
figure taken is 180 days, although the increasing preva-

TABLE II— SHOWING MINIMUM NUMBER OF ANIMALS TO
BE FED DAILY FROM EACH DIAMETER OF SILO

fSu-mfcer of Animals to be Fedt from ea.cK Size

D.oTne^r

Approximate /*lmi-

of Silo

IT\

TTHAmPounnds-Vo

Horses

500-lb

S tocK

Beef

Dairy

^Kee

f~€ * "V

toe Fed Da.lv

Calves

C*^^" ^"t*

Covws

*^

12 Ibs.

2O Ibs.

2^ Ibs

^O Ibs.

p^r"d!V

1 O

5*5

44

^6

21

13

'75"

1 2

755

63

€3

•3S

30

10

S 5X

I 4

I03O

94

ee

JX.

•4 /

26

3-44

16

1 34Q

12 X

\ I Z

<S7

54

34

•446

18

1700

155

1^2

85

GS

•4JL

^567

20

2 1 00

19 1

}-rs

,0^

84

S3

loo

lence of summer feeding is another factor which is
helping to increase the height of silos.

Table III, taken from BuUetin 141 of the Iowa Agri-
cultural Experiment Station, gives the capacity in tons
of various diameters and heights of silos ; also the num-
ber of acres necessary to fill the silo at 15 tons per acre,
and the amount which should be fed daily, this amount
corresponding to that given in the second column of
Table II.

The Wyoming Farm Bulletin suggests that the fol-
lowing formula may prove serviceable in estimating
the actual amount of silage in the silo, assuming that 1
cubic foot of ensilage weighs 30 pounds :

52

TABLE III-

Concrete Silos

-CAPACITY OF SILOS AND ACREAGE NECESSARY
TO FILL

1-rxSidQ.

v-t e'i q K •*

To-ns

1 5 *o-»\ « to tKe.
acme

sXouJ d be Fed
daily Pounds

1 0

aa

4«.

2.8

5X5-

lo

30

<4~T

3.0

S%. S

1 0

3/2.

SI

3.4

ff Z>5

I O

34

5G

3. -7

5 ~Z. 5"

10

3 Q

es

4.3

d" X ^"

IO

•4 O

TO

>».6

j-x<r

IR

X 8

fet

4.1

7 5^-

IA

3 0

G7

4. 5"

7 rf"^"

i jt.

3 Jfc

-74

S-O

7 SS"

12

3 4

80

^".3

~rSS

1 2.

3 G

S7

5". 6

-T6f

1 3

36

94

<2>.4

~7 &S

1 2

4 O

i 01

7.3

7 ^vr.

I 4-

2 a

83

j-.s

1030

1 4

3 O

91

6.1

10 3O

1 4

3 2.

1 OO

6.7 i

IO3O

1 4

34

109

7.2

1030

1 4

36

l Id

7. a

IO3O

I 4-

38

i ae

8.5-

IO3O

1 4

<4-0

138

S>-2

\O~3O

16

Z.8

r oe

7.2

I34O

16

3O

1 19

a.o

/34(?

16

32

13 1

8.7

/340

16

34

1 43

3.5"

/34-C7

16

36

1 ^"5"

10.3

/34O

16

3S

1 67

M.I

/340

IG

-40

/ SO

12.0

I34O

1 8

30

I.SI

10.0

17 OO

16

3 2

166

II. 0

iroo

16

34

181

u.o

I7OO

18

3 6

1 96

13.2

I70O

IS

3S

^ 1 /t

14.1

1700

1 &

•40

223

15.^6

iroo

IS

4*2

;? 46

16.4-

/~7OO

I &

-4-4

2 64

/7.G

I7QO

IS

4G

262

18.8

1700

2 O

30

I 87

IX. 5

2IOO

51 O

32

20-5"

13.6

/2I OO

2O

34

•%. ^.4

I5". 0

»l OO

36

f^43

16.2

2100

2O

4o

28 \

IQ.8

2IOO

X.O

4;2

300

»o.o

2'OO

20

44

3X0

21.3

2' O^

20

46

3^0

22.6

2/00

2O

4-S

3GI

24.0

2IOO

2.0

.50

3S^.

2:£ 5-

»' oo QF

Concrete Silos 53

D

( — )2x3.14xHx30-— pounds of silage.

2
Where D equals diameter of silo in feet.

H equals depth of silage in feet.

30 equals weight of silage per cubic ft.

EXAMPLE: To get the capacity of a silo ten feet in diameter
containing twenty feet of silage.

10
(-)2X3.14X20X30=

52x3.14x20x30=

5X5X3-14X2°X30=47>100 pounds silage.
47,100-=-2,000=23.5 tons of silage.

In the eighth annual report of the Wisconsin Agri-
cultural Experiment Station, Prof. F. H. King gives
the results of investigations to determine the pressure
of silage against the silo wall. It was found in these
experiments that the pressure of silage upon the silo
walls increases with the depth and is equal to 11
pounds per square foot of each foot of depth. Thus at
a depth of 20 feet, the bursting pressure in a silo is
220 pounds per square foot, and at a depth of 35 feet
the pressure amounts to 385 pounds.

Prof. J. B. Davidson, of the Iowa Experiment Sta-
tion, Ames, la., says that a careful investigation of
modern practice proves that an allowance for this pres-
sure is sufficient, and that many concrete silos are now
standing and in successful service with much less re-
inforcement than that required by an assumed pressure
of 11 pounds per square foot per foot of depth. This is
due to the fact that the wall independent of the steel
is able to resist a part of the bursting pressure.

Table IV, prepared by Prof. Davidson, gives the
steel required in cylindrical silos to carry a bursting
pressure of 11 pounds per square foot per foot of depth
and it is based on a safe tensile strength of 20,000

TABLE IV— TO DETERMINE STEEL REQUIRED IN
REINFORCING SILOS

GrQSs-^ectiona^Areq of^Ste

el S JQi | 8| «!

Nurinberlof 2! incHi Squar£ B

! j-| ! : ^ :

drs

; «o| .rj «oi

NurjibeHof ij inert Round R<

! -I j *M|; i fO|:

>(?5
•• •*! mi i o| si

Nur^beij of Ij inolH Rdonc) R<

; . : " i-i i s

3fi

rvj| tO|

Nurjnberj of 2 inoHi Rcjunc) R<

Dds

i - 1 1 1

Nurpbe* of | inch Rqundj R

ods

1 -1

Nurpbei-of jinch Round R

! j -Wl :

otls

-Ml rttai

Sfrjandis of^NcJ-Q VVirei c

Ji! . , i GI i . ^

, Strands of BdrbWirei-2

0 !«0 i, ! , <

,-No.liS Wrres... 0
h , i i . vi . ^

5- - I -

ii

i j £ ^

\>\ V ^

10 s J j i

S kS^^'

C ^ L ^

i i S

! [! 5 ! i I !!

i S S

S ^ * ^ s

i k 5 5 k * t. s

^_. 20 • ..L.(.^ .^ » 1.^1.,..

^ .. ..,. , ., .^. ..

a) ;s 5!S" i >'!

iJ_ :: !i:!:^:r!;!s'::

COC . . . L . ' . . k S S

== » k \ \ S

* k C ^ ' ' 1

o :::::::::::::! ::s:.i:.5]!;:!;:!;

in -^n \ , v ^

u OO i > S

^ ^ i 3 -

o i ;"^"s;

S * ^ | > ^ , •

... .. s

S I

V i " S s rf^*

^1 35 " " ' ' T - - - r - - - r - -

'-l^ S x S'?1

CP ::: : :::: :::s: •;•• ss

•-) : . j * .

. '

•r - — 'ti -\ •••

^40 Hs:l ::.s:;

• i ' - • ^ • • "^: * M — s&J^--~

^ * ^ ' j

45 ••• c — j-s-

S S I i ] ! J ! , .5^ . . -^ . . -

^ . V ^

" ^ ^ L ^ ^

. . j. ...^

' s ' ^

Q 8 2 fi.

^ S3. 8 8

Gross-sectional Area of Sieel per Vertical foot of
WallinHundredths of a Square inch

(54)

Concrete Silos 55

pounds per square inch for the steel. This shows in a
concise form the cross-sectional area of steel required
in silos from 10 to 25 feet in diameter for the top foot
and each successive foot until a depth of 50 feet is
reached. The chart should be held in a vertical posi-
tion. Then, if the point is noted where one of the
heavy diagonal lines representing a silo diameter inter-
sects a horizontal line representing the depth of the
silo, the area of the steel required to resist the bursting
pressure on a section of the silo wall one foot wide
will be found on the scale directly below. The corre-
sponding area in common styles of reinforcement is
found directly above on the upper scales.

CHAPTER VI

THE DIFFERENT TYPES OF CONCRETE SILOS

Concrete silos naturally divide themselves into two
broadly general classes : Those which are built up in
position and which form when completed one practic-
ally continuous monolithic mass; and secondly, those
which are built up from structural units of concrete
previously manufactured.

This is a classification somewhat different from that
used by other writers on this subject, but it is believed
that careful consideration will show it to be logically
correct.

The metal lath silo, for instance, has usually been
considered in a class by itself, and apart from the
monolithic silo. In any broad general classification,
however, it would seem to belong with the monolithic
silo inasmuch as it is built up in place and forms prac-
tically one solid mass when completed, the main differ-
ence being that it is plastered in vertical layers instead
of being poured in horizontal sections. The pit silo, if
it is considered at all, will also come under this classifi-
cation, it being a plastered silo underground instead
of above ground.

This first classification will also include the hollow
wall silo when poured in place.

The second classification will include the silo built
of concrete blocks, concrete staves, or any other form
of structural units which are made previous to the erec-
tion of the silo.

(56)

Concrete Silos 57

The determination of the particular type of silo to
be erected in a given place will depend upon a number
of considerations. While there may be several things
which in any given locality will point to one type of
silo as somewhat more suited to the conditions than
another, the principal consideration governing the
choice will in most cases be found to be the whim of
the owner. It is unfortunate that this is so, but it is
one of the conditions to be reckoned with. Aside from
this, however, there are logical conditions which will
influence, or should influence, the choke of type. Two
extreme cases might be cited as illustrating this.

Suppose, for instance, that there is a good deposit of
sand and gravel on a man's farm, and that there is a
contractor in a nearby village who has a set of forms
for building monolithic silos, and with a reputation for
building them well; these conditions would naturally
point toward the monolithic silo for this particular loca-
tion. On the other hand, suppose another farmer, who
has no available deposit of sand and gravel, but who is
within convenient hauling distance over good roads
from a plant where he can procure structural units of
some kind for silo construction. These conditions will
as certainly point to the use of such units.

There will, of course, be many modifications of
these conditions, at some time some of them possibly
pointing in one direction and some in the other. They
will then have to be weighed against each other and
the decision made in the direction of those which seem
to be most favorable.

The labor situation may influence the selection
somewhat. If stone masons are available and plasterers
are not to be had, this would tend to make one favor

58 Concrete Silos

the silo of structural units as opposed to the metal
lath silo; while with reverse conditions, the opposite
would be the case. A strike in one of these trades
would, of course, throw that particular mode of con-
struction out of consideration for the time being.

The fact that a neighbor has a silo of a certain type
of construction will often influence a man to have the
same type. This method of selection is logical only to
the extent that it shows there is someone in the locality
who can build successful silos of that type and gives the
new builder greater confidence that his silo will be
what it should be. His situation as to materials or
labor, however, may be entirely different, so that this
in itself is not sufficient basis for choice.

There may even be times when one will not be justi-
fied in going to greater expense than that involved in
the construction of a pit silo. In doing this, however,
he must be sure that his conditions are right for this
type of silo, and outlined in another chapter of this
book.

CHAPTER VH

THE FOUNDATION OF THE SILO

The silo is usually allowed to extend into the ground
about 5 feet. In this way the height above ground is
reduced, considerably decreasing the amount of scaf-
folding necessary, and the hoisting of materials, as well
as having the further advantage of placing the founda-
tion below the frost line.

It might at first seem that if a depth of 5 feet is an
advantage, a greater depth would be a still further ad-
vantage; but this is not true, owing to the fact that
when one goes below 5 feet, the difficulty of getting the
silage out of the silo offsets any advantages of con-
struction which might be secured.

When the site of the silo has been selected, a stake
is driven in the center and a sweep is attached to this
stake with a spike, by which the place for excavation
can be marked out. This sweep may consist of a piece
of 2x4, or any other convenient piece of lumber, to the
outer end of which is attached a pointed piece of board,
by which the marking can be done. The length of the
sweep will of course be governed by the diameter of the
proposed silo, as well as the nature of the ground in
which the excavation is to be made. First measure off
on the sweep from the spike in the center stake, one-
half the inside diameter of the proposed silo. If the
ground is firm, so that the walls will stand vertical, 1
foot can be added to this radius. If, however, the
ground is soft and yielding, so that it will be necessary
to slope it back, it will be necessary to add about
feet.

(59)

60 Concrete Silos

If a floor is to be put in, the excavation should be
carried down to 4 inches below the top level of the
floor, making a 4-inch slab.

Under certain conditions, the silo floor may -be dis-
pensed with without interfering with the preservation
of the silage. Where the silo rests upon dry clay or
any non-porous soil, and where the foundation is deep
enough to prevent undermining by rats, the floor may
be omitted. In general, however, a floor is quite de-
sirable. The portion of the silo below the ground may
be made more nearly water tight, the floor may be thor-

Sweep for Laying Out Excavation.

oughly cleaned, and there is no mixing of earth with
the silage. A silo floor need not be thick or expensive,
as the weight of the silage, though very great, is dis-
tributed evenly over the surface and would be just as
firmly supported if the floor was not used.

After the excavation is leveled off for the floor of
the silo, the digging is then continued around the cir-
cumference of the pit for an additional depth of 8
inches, and 24 inches in width, to provide for the foot-
ings, as shown in the drawing. It is a good plan to
provide in the center of the silo floor a connection with

Concrete Silos

61

Excavation, Floor and Footing1. Earth Wall Can Be Made
Vertical Where Ground Is Firm.

a line of drain tile. This drain will carry off any water
which may accumulate in the silo, and which, in some
cases, has been known to rise to such a height as to
exert a pressure on the silo walls greater than they
were designed to resist. If a drain is used, the floor of
the silo should have a pitch toward the center of about
i/4 inch to 1 foot. The drain should also be covered
with wire netting to keep it open, and should be pro-
vided with some form of trap so that the air cannot
enter from the outside.

If the foundation walls on the silo are made thicker
than the walls of the superstructure, they should line
up with each other on the inside rather than the out-
side. A few years ago it was thought proper to place

Correct Method of Alignment Between Wall and Foundation
Shown at A. Incorrect Method at B.

62 Concrete Silos

the upper part of the silo at the outer edge of the foun-
dation walls. The shoulder was thus left projecting
into the silo. Owners of such silos report a large
amount of rotten silage around the joints. This is ow-
ing to the fact that the silage does not settle properly
where such joints occur, leaving pockets of air which
cause rotting of the silage. In some cases the owners
have felt it worth while to sacrifice a part of the ca-
pacity of their silos by filling them up to this shoulder.

If the ground is firm it can foe used as an outside
form for the foundation walls, using an inside form of
wood or metal.

It may be said, however, that while it has been the
custom in the past to build a foundation wall up to
about a foot above ground, irrespective of the kind of
construction to be followed above that point, the prac-
tice is coming into quite general use of starting the
walls of the structure directly on the footing, making
them uniform from that point to the top, whether they
be of monolithic construction, blocks, staves, or plas-
tered on metal lath. This is a more simple method of
construction, except for the fact that in some instances
this may require a little more excavation.

Where a silo is to be reinforced vertically, this re-
inforcement should be imbedded in the footings and
allowed to project from them up into the walls.

CHAPTER VIII.
THE MONOLITHIC SILO.

The word "monolith" is derived from two Greek
words and means, literally, a single stone. The term
"monolithic" is therefore applied to concrete struc-
tures which are built up in one continuous process and
form practically a single stone when they are
completed.

As stated in a previous chapter, any broadly general
classification of silos would include under this heading
not only the silo which is built up of either solid or
hollow walls poured in forms, but also the pit silo and
the silo plastered on metal lath. These others are,
however, dealt with in separate chapters further on in
this volume ; and as a number of different systems have
been developed for constructing the silo of poured
walls, these too have been dealt with in other chapters,
so that this chapter need only concern itself with a few
general observations on this type of silo.

It has been the custom in the compilation of
bulletins by the U. S. Department of Agriculture, the
experiment stations of the several states, and the
bulletins of the cement companies, to give detailed
directions for what 'are known as "home-made" silos;
that is, silos built wholly or largely by the farmer him-
self, and in forms which are also of his own manu-
facture. The present writer, after having given the
subject careful consideration, has not seen fit to include
such matter in this volume. While undoubtedly a large
number of very satisfactory silos have been built in this
way, the practice is not to be recommended. The

(63)

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(64)

Concrete Silos 65

writer firmly believes that every silo should be erected
by 'a contractor who is familiar with this class of work.
There have been failures of concrete silos in the past
and the opponents of this form of construction have not
hesitated to use these instances to the best advantage
in inviting public condemnation of concrete.

It is absolutely necessary for the benefit of the
industry that no more such failures should occur; and
one of the best expedients for preventing their recur-
rence is to allow only an honest and experienced con-
tractor to put up a concrete silo. Such a contractor
will scarcely care to bother with making his own forms,
which at best will be awkward and inefficient,
especially in view of the fact that there are on the
market a constantly increasing numbjer of commercial
forms, and that the manufacturers of these forms are
continually improving them and adding to their
efficiency for construction.

A home-made form will perhaps build a dozen silos
at best, when it has to be discarded and replaced. It is
a makeshift proposition, cumbersome and inefficient,
difficult to handle" and inexact in its alignments. A
properly built commercial system, on the other hand,
will last at least for several seasons of work, is con-
ducive to rapidity and economy of construction, and
shows a finished structure which is exact in every
detail.

In employing a contractor to build a silo, the farmer
can, of course, have it understood that he is to supply
the materials if he has them on his farm, or that he is
to do the hauling, furnish some of the unskilled labor,
or assist in any other way of which he is capable.

Another advantage in having this kind of work
done by a contractor is that the contractor will have a

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(66)

Concrete Silos 67

concrete mixer on the job, while the farmer himself
would frequently be satisfied to mix the concrete by
hand. On a structure such as a silo, which is built with
a comparatively thin wall, and which at the same time
has to withstand considerable strain, it is of the utmost
importance that the concrete should be well mixed, so
that it may attain its greatest strength.

For the same reason, too, considerable care should
be given to the materials, making sure that they are
clean and properly graded to make a concrete of the
greatest density. Sand and gravel for silos are as
often as possible secured from deposits in the locality,
rather than being bought from commercial plants, and
hence need most careful inspection. Gravel taken
from a creek is often coated with clay loam, which
prevents the cement from making a good union, and
very often it contains particles that are too large or of
a crumbling character. Such gravel should be run
over a screen and wrashed before using. Soft granite,
shale, slate rock or dusty cinders are not desirable.
The material should not easily crush and disintegrate
and should be suitable to give a good, strong union
with the cement. Above all it should be repeated that
it should be absolutely clean.

In some localities there are natural deposits of
gravel containing varying proportions of sand. If
clean and not too coarse, such gravel is well suited for
silo building; but in using this material it is never safe
to assume that the proportion of sand to gravel is cor-
rect until a quantity has been run over a ^-inch screen
and the exact proportions determined. Usually such
gravel contains too much sand.

For the foundation the stone may be as large as
will pass through a 2%-inch ring, while for the main

68 Concrete Silos

TABLE VII.— AMOUNT OF REINFORCING IN TWISTED

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This Table, Which Is Adapted From Tables Compiled by the Reich
in Height. For Silos of Less Height, Cut Off the Diagram at the Figure

Line, Using the Steel Called

Concrete Silos 69

STEHL BARS FOR SILOS OP VARIOUS DIAMETERS.

ao rr. OIA

ert Manufacturing- Company, Shows Reinforcing- for Silos Up to 60 Feet
Indicating the Desired Height, and Disregard Everything Below That
for Above the Line.

70 Concrete Silos

wall of 6-inch thickness the size should not exceed lJ/2
inches. A mixture of particles of various sizes from y%
up to 11/2 inches makes the strongest wall.

The water used for mixing concrete should be clean
and free from alkalis and acids. It is especially desir-
able to caution builders of farm structures on this
point, because drainage water from the barnyard or
water from a muddy stream may sometimes find its
way into the supply.

The usual proportions for a 6-inch concrete wall are
1 part of cement to 2 parts sand and 4 parts stone.

In filling the forms, only a few inches in depth
should be filled in at one place at a time. Depositing a
great quantity of concrete at one place puts a heavy
strain on the forms and has a tendency to force them
out of plumb. As the concrete is put into the form it
should be spaded with a piece of 1 by 3 inch board,
sharpened to a bevel edge. The purpose of the spading
is to remove all air bubbles and avoid the formation of
cavities. On the other hand, in a wet mixture as used
in silo building the spading must not be overdone, or
the heavier rock will sink to the bottom and the cement
and water will rise to the top.

The exterior surface can be kept smooth by greasing
the outside form with soap or some cheap oil or grease.
To be effective this grease coat must be renewed at
each raising of the forms. No grease should be used on
the inside form, as this surface is to receive a brush
co'at of pure cement wash. Small particles of cement
will adhere to this form each time it is raised, and
before it is used again these should be removed with a
broom or a wooden trowel. If these are not removed
an undue amount of concrete will adhere, and this will
result in an unnecessarily rough wall.

Concrete Silos

71

X*-—" *V

V

Showing- the Difference Between a Silo That Is Brush Coated
and One That Is Not.

As the forms are raised the fresh wall is constantly
exposed to the drying air and sun, and there is danger
of the surface drying and curing too rapidly for the
interior of the wall, causing cracks. To prevent this
the wall should be soaked with water several times a
day for several days and when possible the wall should
be protected with canvas or burlap thoroughly wet.

72 Concrete Silos

When the forms have been filled for the day do not
smooth the top with a trowel, but leave it as rough as
possible. A good plan is to roughen the top surface
just as the concrete starts to set. Before putting fresh
concrete on this wall the next day, the top surface
should be soaked with water 'and then sprinkled with
raw cement, which will help in making a good union
between courses. The forms must not be removed for
at least 5 hours after filling.

A brush coat of cement wash may be applied as
soon as the form is raised and before the wall has had a
chance to dry. This coat of cement helps to make the
wall less porous and therefore more nearly air and
water tight. The wash is prepared by mixing together
cement and water to the consistency of thick lime
whitewash, and is applied with a whitewash brush in
the ordinary way. If the wall has had time to dry it
should first be drenched with water.

After this coat of cement wash has been applied the
whole interior may be painted with coal tar thinned
with gasoline. The coal tar makes the wall impervious
and also protects it from the action of acids which
develop in the silage. It should be renewed from year
to year as may be required. The application of the
coal tar may be left until the wall is complete, but
should be done before removing the interior scaffold.

CHAPTER IX.

THE POLK SYSTEM.

This system of silo construction is controlled by the
Polk-Genung-Polk Company of Fort Branch, Indiana.
It has as its basic principle of operation a center mast,
erected at the center of the floor of the structure and
carefully plumbed by means of guy wires attached to
the top and provided with turn-buckles. From this
mast everything used in the construction of the silo is
suspended, including the staging, the apparatus for
handling the forms, and the crane for hoisting and
depositing the concrete.

The mast is a four-inch steel pipe, provided with a
series of transverse holes to receive a heavy steel pin.
This pin supports a widely flanged collar, which serves
to support the jacks by which the forms are lifted.

Resting upon the jacks is a hub, consisting of a
flanged base collar and a top dished collar connected
by a central pipe of sufficient diameter to work easily
over the center mast. From the base collar of this hub
radiate steel tees which are supported from the upper
collar by adjustable hanger rods with chain clevises.

Each form consists of eight separable sections, and
each section is reinforced and stiffened by a steel angle
frame around the edges. The inner and outer steel
wall-forms, which are rolled to the required curvature,
are bolted to the radiating steel tees. The outer sec-
tions are bolted together at their ends through holes in
the frames. The inner sections are similarly bolted
together, but carry steel wedges between them, the

(73)

74

Concrete Silos

The Polk System Equipment

Concrete Silos

75

lifting of which allows the inner sections to swing free.

To keep the vertical reinforcing in its proper posi-
tion in the center of
the wall, small steel
clips are provided.
The vertical reinforc-
ing passes through

these clips, which fit I k

over the stems of the
steel tees.

For placing tine
concrete between the
forms, a V-shaped
dumping bucket is
provided. This buck-
et is supported by a
crane pivotally at-
tached to the cen-
ter mast directly
above the top collar
of the hub, and can be easily swung to any part of the
wall space. It is hoisted by means of a rope and series
of pulleys so arranged that the hoisting force is applied
horizontally from without the structure. A small open-
ing, through which the hoisting rope works, is cut in
the wall near the bottom of the first fill of concrete.
When the bucket is hoisted it is coupled to a carrier on
the crane by means of a hinged hook and is then swung
to any part of the wall space desired.

The scaffolding, both inner and outer, is swung from
the steel tees, which project some distance beyond the
wall.

The operation of the machine is very simple. The
forms are set, the reinforcing bars are placed in posi-

Polk System Machine in Operation

76

Concrete Silos

tion, the concrete is mixed, hoisted, dumped and
packed between the forms, and allowed to set. The
next morning the nuts connecting the sections of the
outer form are loosened, the steel wedges fixing the
sections of the inner form are lifted, and both inner
and outer forms swing free from the wall. Then, by
means of the jacks resting on the widely flanged base
collar, the whole mechanism is lifted until in position
for a new fill and the forms are again set by means of
the bolts and wedges. One fill a day is the customary
rate of progress.

These silos were
originally made with-
out chutes, but a
chute form is now an
integral part of the
system.

This chute form is
carried by two of the
steel tees which are
longer than the rest
and is attached to
the outer set of
shells, taking the
place of one of the
separable sections. It
is set to maintain the
continuity of the silo
wall and to mould a
chute wall of a thickness of 6 inches where it joins the
silo wall, gradually decreasing to 4 inches at the out-
side. The outer shell of the chute form is released and
bolted up in precisely the same manner as the outer
form of the machine is released and bolted up, the

Twin Silos, 16x72 Feet, at Dayton
State Hospital, Dayton, Ohio

Concrete Silos 77

outwardly curved sections forming the wall imme-
diately adjacent to the silo wall proper being attached
to the regular outer form sections. The inner form is
released and set by means of a steel wedge similar to
those used between the sections of the inner shell
proper.

Provision is made for the forming of doors opening
into the chute and for the construction of a steel ladder
inside of the chute. Reinforcement for the chute is
handled as in the silo wall.

The elliptical openings which are formed for the
doors are 20x30 inches. They are usually spaced 24
inches apart, but the number and arrangement of doors
are optional with the builders. The elliptical shape
has been chosen in order to avoid sharp angles. For the
formation of this opening a sheet steel door is set be-
tween the shells of the machine as the work progresses.
This form moulds a concrete jamb 1 inch in width and
1/2 inch in depth from the inner surface of the wall.
Owing to the shape and draft of the form the jamb is
left in perfect condition for sealing the door. Imme-
diately after the machine has passed the opening the
door form is removed.

The door itself is made of heavily galvanized sheet
steel, cut to fit snugly into the concrete jamb made by
the form, flush with the inner wall and bent to the
radius of the silo. On the outside of the door are
fastened four malleable clips in which hook bolts en-
gage. Across the opening on the outside of the silo
wooden bars are placed through which these bolts pass.
The desired stress is obtained by malleable tail nuts.
In sealing the door a thin gasket of moist clay is
smeared around the jamb before the door is set in
place.

78 Concrete Silos

The silo ladder is made of l^xl^x^ inch steel
angle runners and lxlx% inch steel steps, the joints
being electrically welded. It is secured to the concrete
wall by strap screws which are screwed into spiral
steel anchors imbedded in the wall during construc-
tion. When the wall is completed the temporary fillers
in the anchors are removed and the strap screws are
firmly inserted. The ladder is then bolted to the strap
screws and is ready for use. Ordinarily the ladder is
made up in 10-foot lengths, but sections of any length
may be cut.

CHAPTER X

THE MONSCO SYSTEM

This is a system of construction with metal forms
controlled by the Monolithic Silo and Construction
Company, Chicago. These forms are made of No. 16-
gauge galvanized sheet steel and are held true to shape
by curved steel angle irons welded to the sheet, which
reinforce the steel plates at the edges and through the
middle. The forms are made in sections 3 feet high
and the circumference of the silo is divided in 5 to 8
segments, according to the size, this including the form
for the chute, which, if desired, is cast at the same time
as the walls of the silo. Sufficient forms are used in
an outfit to form two complete circles around the silo.

In starting the construction of the walls, one circle
of these forms is placed on the foundation and poured
full. The next circle of forms is then clamped to these
and poured. This 6 feet will usually constitute a day's
wort. The next morning the bottom circle of forms
is raised to the top and filled, after which the section
below is raised and filled, this constituting the second
day's work, and the operation is repeated until the
desired height is reached. In other words, the operator
is always pouring into a 3-foot section of mold firmly
clamped to another 3-foot section filled with concrete,
the concrete set sufficiently to eliminate the possibility
of a wall fracture.

These silos have 6-inch walls, the thickness being
the same from top to bottom. Forms are made for
diameters of 10, 12, 14, 16, 18 and 20 feet.

(79)

80

Concrete Silos

WIRET5

-4-*- RODS COVERED BY

" p.pe:

Equipment for the Monsco System.

Concrete Silos

81

Completing- a Monsco Silo.

The construction is carried on by means of a center
mast of steel, this mast carrying a steel frame for
staging and also a revolving derrick carrying the
buckets, by means of which the concrete is elevated
and deposited. The elevation on the mast of both the
staging and derrick are under control of the men on
the staging, so that they can be readily moved up as
the construction proceeds. The mast and staging

82

Concrete Silos

Section of Mold

Chute.

frame are entirely separate from the wall forms, the
latter depending entirely for support on the 3 feet of
wall when closed by the lower circle of forms ; and as
the upper section of the staging frame is always above
the wall forms the same outfit will, of course, answer
for varying diameters of silos.

These silos are reinforced with triangle mesh rein-
forcing, the selection of the reinforcing depending
upon the size of the
silo and being selected
usually to provide suf-
ficient strength with-
out placing any addi-
tional wires. The
company recommends
a 38-inch width, this
allowing a 2-inch lap
between courses. After a circle has been poured and
it is desired to move up the lower section of the forms,
the bucket at the end of the derrick is taken off and
a wooden seat is suspended from the hook in its place.
By this means a man is lowered to the outside of the
forms and removes the clamps which hold the two
sections together. The forms are drawn up by men

on the scaffold
by means of
hooks which
engage in holes
in the angle
iron welded to
the top of the
forms. The in-

Monsco Roof Form.

side forms are
m a n i pulated

Concrete Silos 83

from a small auxiliary platform suspended below the
main platform of the scaffold. As the construction is
carried up, the mast is raised 'by means of two cast-steel
worm-geared winches.

The door on this silo is of the continuous type. It
has a gas pipe running through the concrete on each
side, and around which the ladder irons are engaged.
The gas pipe has several strands of wire extending
around it at frequent intervals and running back into
the concrete 2 or 3 feet in order to provide a sufficient
anchorage. The doors themselves are of wood.

A special roof form, making a concrete roof, with
dormer, is also supplied if desired.

CHAPTER XI

THE EEICHEKT SYSTEM

This is a system of monolithic construction devel-
oped by the Reichert Manufacturing Company of Mil-
waukee. It differs from other systems of this type in
that the forms are made in sections 24 inches square,
instead of in larger sections, so that each can be handled
easily by one man. The small size also makes for ad-
justability, a feature which is still further provided for
by the fact that the sections are reinforced at top and
bottom with strap steel instead of angles, thus allowing
them to take the curvature of the particular size of silo
under construction, to which they are then held by a
rigid inner steel circle and by spacers placed at suit-
able intervals. Silos of all diameters are thus made
with the same outfit, except that fractional plates have
to be used to fill out for the various sizes where the
circumference does not work out in exact multiples of
24 inches.

An outfit consists of sufficient forms for three rings
around the silo. This is enough for one day's run,
or 6 feet in height, the practice followed by most con-
tractors in using this system, although some are erect-
ing 8 feet per day.

The sections are reinforced vertically with angle
irons, and when assembled the vertical joints are se-
cured by clamps. These clamps are attached to one
angle of each section and when in place fit down over
the angle of the adjoining section, a push of the lever
driving them up tight. These levers are downward act-

(84)

Concrete Silos

85

ing, so that when it is
desired to release
them a jerk with the
hook from above is
all that is necessary.

Each section is
joined to the one
above it by a hook at-
tached to the upper
edge of the lower sec-
tion, which hooks
over a raised rivet on
the lower edge of the
section above. This
hook is pivoted and
has a hole in the
shank, so that a work-
man above, after rais-
ing the side clamps
with a long hook,
which is a part of the
outfit, can insert the
point of the hook in
the shank of the hook
on the lower form,
with one operation
disengaging the form
from the one above it
and drawing it up
into its new position.

There is in this sys-
tem a center mast of
steel tubing, carrying
collars which can be

Reichert Silo With Square Chute

86 Concrete Silos

moved up 'as the work progresses and to which the radial
staging arms are attached. There are two sets of these
arms. The upper platform is flush with the top of the
silo, from which the forms are manipulated arid the pour-
ing is done. Each of these arms consists of two angle
irons telescoped on each other and with bolt holes at
suitable intervals, so th'at they can be adjusted to the
various diameters it is desired to build. At one end they
rest in slots in the collars on the mast, and at the other
end they rest on the circles of angle iron which are car-
ried right up with the forms to give them their true
shape. These circles are made in segments for easier
handling, but can be rigidly clamped together for use.

The upper ring, which holds the forms in shape, also
c'arries a single track on which run the two wheels of a
small car. This car rests on a frame attached to a loose
collar around the mast and just above the collar which
carries the upper platform. It thus can be pushed
around to any p'art of the circle desired, swinging
around the mast as a pivot and the outer end carried by
the wheels on the track. This car is merely a frame
with bearings on which the bucket of concrete can be set
when it is brought up from below, the arrangement being
such that it can be tilted to dump into the forms, a steel
apron being attached to the 'car to direct the flow into
the forms and prevent loss of concrete.

A derrick, also attached to the mast in the center,
by which all materials are handled, completes the
outfit.

The ordinary wall thickness in this system is 6
inches, though the adjustability is such that almost any
desired thickness can be obtained, the only additional
parts of the outfit needed being spacers for the desired
thickness and perhaps additional fractional plates in

Concrete Silos

87

order to make the outside ring fit the change of circum-
ference.

Two types of chute are provided for: a square
chute is made with
the ordinary flat
wall sections made
by the Reichert
Manufacturing Com-
pany, or a curved
chute made with
special sections pro-
vided for the pur-
pose. This System COn- Completing a Conical Roof

templates the use on a continuous door, and door frames
are provided with the outfit, to be set into the forms.
They are slotted to carry the ladder irons. Intermittent
door forms -can also be supplied if desired.

Reichert metal roof molds are made in two types.
One of these is a dome roof, the form consisting of
curved segments which rest on the silo wall proper and
are locked to a hub at the top. The angles of the
separate sections fit into slots in the hub, thus locking
the entire equipment
together. The other
type of roof consists
of straight segments
resting on the side
walls and bolted to a
ring at the top. The
roof molds include
complete equipment

for making cornice and dormer window. No part of the
mold is left in the structure, all being taken away and
used repeatedly.

Form Assembled for a Dome Roof

88 Concrete Silos

The reinforcing used in the Reichert silos is either
Triangle mesh or square twisted steel bars. The mesh
is used according to the table of the American Steel
and Wire Company, as given on page 66. The bars are
placed according to individual plans for each size as
drawn up by the Reichert Manufacturing Company.
Table VII, on page 68, gives in somewhat shortened
form the scheme of reinforcing with bars as used by
this company.

CHAPTER XII

OTHER MONOLITHIC SYSTEMS

Peerless Silo Molds. These molds are controlled by
the New Enterprise Concrete Machinery Company,
First National Bank Building, Chicago. They are made
of sheet steel, reinforced with iron frame, and are suffi-
ciently flexible so that various diameters of silos can be
made with the same forms by using smaller plates to
bring them to the proper circumference. The inside
form is a No. 16
steel and the outside
form is a No. 18. The
chute is poured at the
same time as the main
body of the silo wall.

The unusual fea-
ture of this system is
the combined derrick
and scaffold which
rests upon the con-
crete wall, doing
away with the necessity of building up staging from
the ground. The derrick and staging are raised
by four small jacks or raising devices, stationed
at the quarter points of the circumference, with a man
at each jack. By this means the derrick-scaffold is
raised first, before the forms are drawn up into place.

These molds have a daily capacity of 5, 6, or 7%
feet, depending on the number and type used. The 6-
foot molds are made in two rings of 3 feet each. The

Peerless Outfit.

(89)

90

Concrete Silos

Peerless Silos at State School, Lincoln, 111.
Dimensions, 17x50 Feet.

usual custom at present, however, is to use 3 rings of
2% feet each, thus building 7% feet of wall each day.
Molds are built for a 5-inch wall unless otherwise
preferred.

Triangle mesh is used throughout for reinforcing.
Metal doors and door frames of the continuous type,

Concrete Silos

91

Peerless Outfit.

First Ring- of Mold Filled and Derrick Raised
to Receive Second Ring.

and either metal or concrete roof are included in the
construction of these silos.

Martin Adjustable Steel Silo Forms. These forms
are made and sold by the Martin Concrete Form Com-
pany, Ottawa, Kan. They build silos from 12 to 20
feet in diameter.

The outside form is made of 14-gauge steel and the
inside form is made of 12-gauge steel. The top and
bottom of the inside form are held in place by angle
iron braces radiating from the center. Each section
of the inside form is adjustable to a larger or smaller
circle by means of turnbuckles. The size of the form
is also changed by adding sections and adjusting the

92

Concrete Silos

curvature of each section. The ends of each section
are made with slideable edges and are provided with
turnbuckles for con-
tracting and expand-
ing the forms.

The form is raised
by means of jacks
operated from the
platform. The rein-
forcing rods run
through the jacks.
At the bottom of
the jack is a collar
clamped to the rein-
forcing rod which
supports the jack.
The extension yoke
which is attached to
the inside and out-
side form is bolted to
the stationary nut of
the jack. By turning
the screw the nut is
pushed up, pulling
the form with it.

These forms pro-
vide for building 6
to 10 feet of wall in
height per day.

Intermittent metal doors are used in this system.
They are 20x22 inches in size, and are made entirely of
cast iron except the hinges, which are mild steel. The
frames are also of cast iron, and carry a groove for

Building' a Silo with Martin Forms

Concrete Silos

93

felt packing. They are set into the forms as the
concrete is poured.

Van Guilder System. This system, which is con-
trolled by the Van Guilder Hollow Wall Company,

Van Guilder Hollow Wall Form

Rochester, N. Y., makes a silo with either a single or
a double wall. Either type is made with a small
machine, as shown in the illustration, which is set on
the footings tamped full of concrete, then removed and
carried around to a new position, the operation con-

94 Concrete Silos

tinuing until a complete circle has been made. The
machine is then set on the section of wall thus made
and another section is carried around in the same way.
The double wall machine makes a 4-inch air space and
the walls are adjustable for thickness of from 4 to 6
inches. The single wall machine can be adjusted to
make walls from 5 to 8 inches thick. The machine is
not adjustable to different diameters of silos.

The Conklin System. Made by the Conklin Construc-
tion Company, Hartford, Mich. The molds are of
No. 16 black sheet steel held in shape by l^xl^
angles riveted on. The inside forms are also reinforced
with l1/^ inch channel steel in the center to keep them
from buckling. The forms are made in sections 4 feet
high, and two complete circles constitute an outfit,
sufficient for a day's work of 8 feet of wall.

The hoist is operated on a center mast of a 4-inch
gas pipe and in 10-foot lengths with slip joints. One-
inch holes are drilled at proper distances through the
center mast for 1-inch pins. The jack bench and spider
hub rest on the pins through the center mast.

There are eight tee irons radiating from the spider
hub and supported by rods and chains from the casting
above. The rods and chains are adjustable. On the
ends of the tee irons are adjustable tee irons or arms
that may be taken up or let out for the different sizes
of molds. Boards are laid on the tee irons to make a
scaffold for the men to operate the machine.

From every other tee iron are suspended %-inch
rods (4 in all) to hold two timbers (2x6 inches), on
which a scaffolding is built completely over the inside
of the silo. The men stand on that scaffold and do
their work inside the job.

Concrete Silos 95

The boom is supported by two %-inch rods with
turnbuckles which swing around the center mast. It
carries a car or traveler which carries the hoisting
cable and cement bucket.

The derrick is also used as a means of support for
the workman who uncouples the outer forms when
they are moved up.

A sufficient area of steel is provided in the cross
wires of triangle mesh reinforcement to prevent tem-
perature cracks, thereby eliminating the necessity of
laying additional reinforcement at right angles to the
longitudinal or tension members. The common width
is 54 inches. This allows for a 6-inch lap on each 4-foot
section poured.

The -Conklin silos are equipped with continuous
doors, 30x30 inches, of 1-inch lumber, with tar paper
between, with felt gasket between door and cement.
The doors are set in a 2-inch cement jamb, forming a
solid construction. Ladder irons are placed about
every 30 inches, made of 1-inch mild steel.

The Conklin equipment is adapted to build the non-
continuous type of doorway by leaving out the steel
forms for blocking off the continuous doorway and
adding the special form in the chute for making the
non-continuous. By using this special form, any style
of door (elliptical or square) can be used, by placing
the door form between the special chute form and the
inside silo form.

The 2-E Flexible Silo Form. This form is 5 feet in
length and build either a hollow or solid wall. In
building the silo the form is placed on the foundation
and filled and tamped, then moved to a new location
and filled again, the operation being repeated until the

96 Concrete Silos

entire circle is completed. The courses are 10 inches
high. The form is sold by M. L. Schluetter, 223 West
Illinois Street, Chicago.

Blumer's Perfect Silo Forms. These are galvanized
iron forms reinforced with angle irons and made in
large segments so that two or three large sections, pos-
sibly with a small filler, will make a complete circle
around silo. Bracing rods are attached to the inner
sections, across which plank may be placed for work-
men to stand upon while drawing up sections or filling
in with concrete. These forms are sold by St. Jacobs
Lumber and Hardware Company, St. Jacobs, 111.

CHAPTER XIII
THE PIT SILO

Instead of being built above ground, as is the ordi-
nary fashion, a silo may consist of a hole excavated in
the earth and plastered with cement mortar. This is
known as the Pit Silo.

This type of silo has apparently but one advantage,
and that is the advantage of cheapness. A pit silo is
not to be considered as a permanent improvement. If
it is necessary to put in a temporary expedient, how-
ever, as is the case of a tenant on a farm, who would
in many cases not be justified in going to the expense
of building a permanent silo, the pit silo will do very
well. In fact it will fulfill its purpose much better
than the wood silo, the only other type of construction
which would be considered under such circumstances,
and is usually much cheaper as well.

It must be borne in mind, however, that it is not
practicable to build pit silos in all localities. They
can be built to advantage only in soil which has a low
water level, so as to preclude the possibility of damp-
ness in the silo.

The depth of 20 feet is considered about the limit
of practicability for such a silo in any event because of
the difficulty of removing the silage; but it should not
go to this depth if there is a possibility of striking
water. Of course it would be possible to seal a structure
effectually against moisture, even at a considerable
head ; but this would be an expense which such a struc
ture would not justify, it being much better to expend
the money on an above-ground silo.

(97)

98 Concrete Silos

While silage will keep very well in a pit silo if the
silo is made moisture proof, there is one insurmountable
objection to this form of silo as above suggested, and
that is the difficulty of getting the silage out. The
advocate of this form of construction will say that this
is offset in a measure by 'the ease with which the pit
silo is filled; but when it is considered that the filling
is done in favorable weather, while the silage is re-
moved during the winter, this does not constitute as
great an offset as might at first appear. Furthermore,
there is a tendency in constructing the pit silo to rely
entirely too much on the stability of the ground, simply
giving a plaster coat to form a smooth interior wall.
This plaster will crack sooner or later, depending on
the condition of the soil; while, if the builder goes to
to the trouble of preparing an inner form and pouring
a substantial monolithic wall, this expense, added to
the cost of excavation, will show little gain over an
above-ground silo.

In the case of pit silos it must also be remembered
that there is a possibility of carbon dioxide gas collect-
ing in the bottom and making it dangerous for persons
to enter. This gas is apt to form in larger quantities
within a day or two after the filling begins, so that if
it is necessary to partially fill the silo and then let it
stand for a time, a lighted lantern should be lowered
into the pit before entering it. If it is found to contain
gas, running the cutter for a few minutes and empty-
ing its contents into the silo will usually set up a suffi-
cient current of air to carry the gas away.

There are three types of pit silos: Plain holes in
the ground, where the walls are plastered and the silage
is cropped in and lifted out at the top; holes in the
ground, but with the silo extended above the ground

Concrete Silos 99

from 4 to 12 feet, the roof placed above this, and the
silage removed through the side of the upper part;
silos built similar to either of the other two, but set in
the bank so that retaining wails which act as a chute
are placed up and down beside a line of doors. If there
is a bank barn and the retaining walls connect the silo
to the barn, the conditions are ideal.

Of the three types of pit silos mentioned above, the
last is the most convenient, also the most expensive.
The first is the cheapest
and likewise the least con-
venient.

Most silos are con-
structed by commencing
at the bottom and build-
ing up; but a pit silo can
be constructed by com- section Through Pit sno
mencing at the top and

building down. By building a silo in this manner, the
ground a-cts as a staging and no lumber or labor is re-
quired for that purpose.

The first step in the construction of a pit silo con-
sists in affording sufficient protection to the edge of the
excavation to prevent crumbling or caving. An exact
circle should be marked out on the ground of the size
of the proposed excavation. Immediately outside of
this circle a trench should be excavated not less than
18 inches deep and not less than 1 foot wide. This
trench should be filled with concrete properly made.
As soon as the concrete in the trench has set and suffi-
ciently hardened the excavation may be proceeded with.

A hay carrier track should be arranged above the
proposed excavation at sufficient height so that the dirt
from the carrier may be dropped into a wagon placed

100 Concrete Silos

for the purpose of receiving it. This track should have
an upward slope toward the wagon so that when the
carrier is unloaded it will return of its own weight to
the stop, which should he placed exactly above the
middle of the silo.

The carrier is best made of a strong box with a
hinged bottom, with a fastening that may be easily
secured and easily loosened. This may be attached to
the hay carrier by chains or ropes so arranged that the
box when loaded will b'alance. A horse on the end
of the tackle rope or -a gasoline engine with a lifting
appliance will do the lifting. When this appliance is
arranged in a satisfactory manner it becomes an easy
matter to take care of the earth from the excavation.

The excavation should be made in such a way that
the walls are perpendicular and smooth. When the
excavation has been carried to about 10 feet (and this
distance is chosen because experience has proved that
it is most satisfactory for the purpose), the walls of the
excavated part should be given a good coating of the
best cement concrete mixture. This should consist of
not less than 1 part of Portland cement to 2% parts of
screened sand. The sand should be sharp, not too
coarse, and free from 'clay. The first coat should be
left rough, and the second coat immediately applied
before the first coat hardens. In order that this work
may be well done, it is best to employ an experienced
mason for this purpose. The first two coats should
constitute a single coating not less than %-inch in
thickness. When this coat has had sufficient time to
harden enough to be protected against injury, the ex-
cavation may be continued to another depth of 10
feet, and the plastering repeated.

Concrete'Silos

•101

It is well to provide for some drainage at the bot-
tom of the silo. This may be done in the following
manner: When the excavation is finished the earth
floor of the silo should slope toward the center. Here
a hole should be dug large enough to receive a drain-
age tile 30 inches long of any desired diameter. The
drainage tile should be inserted in this hole, and cov-
ered with an iron grating with a mesh sufficiently
small to be a protection against rodents. The bottom
should then be covered with cement in the same man-
ner that the sides are covered, and this cement should
join the grating and hold it in place. Any moisture
that accumulates in the silo may in this manner be
drained off, preventing both annoyance and waste.

For convenience, it is better, after the silo has been
finished, to put a masonry extension above ground for
a distance of at least 4 feet, with a door upon one
side through which the carrier used in removing silage
may pass. This extension may be built of poured con-
crete, providing forms can be made for the purpose,
or it may be made of concrete blocks properly con-
structed, or of any material that to the builder seems
most desirable.

A roof should be provided, and this should be made
in such a manner as to allow the free use of the car-
rier and track that are used in removing the silage.

If it is desired to give the pit silo somewhat more
stability than can be attained by plastering on the
bare ground, a metal fabric can be used and the plas-
ter coat placed on this. Stakes can be driven into
the earth walls of the silo and the metal fabric fas-
tened to these stakes.

CHAPTER XIV

THE METAL LATH SILO

The construction of the metal lath silo has been
treated in considerable detail by Mr. Geo. C. Wheeler,
specialist in animal husbandry of the Kansas State
Agricultural College, Manhattan, Kans., in an article
published in a bulletin of that institution. This article
has also been reprinted, with slight modifications, by
the Northwestern Expanded Metal Company, of Chi-
cago, and we can do no better than to follow quite
closely the information there given.

The first round of the metal lath which forms the
chief reinforcement of this silo must have its edge em-
bedded 5 or 6 inches in the top of the foundation, in
order to insure a perfect union between the foundation
and the wall proper. When the footing trench has

Cross Section of Foundation of HY-RIB Silo.

been filled to within about 6 inches of the top and the
concrete brought to an approximate level, the lath,
which comes in strips 8 feet long and 18 inches wide,

(102)

Concrete Silos 103

should be stood on edge on this base and concrete
should be poured on both sides of it. Its position
should be on a circle having a radius 2 inches greater
than the inside radius of the finished silo. The strips
of lath should be lapped about 3 inches at the ends.
When the circle is completed, the wall outside of the
lath should be carefully leveled. In eight or ten hours
the dirt inside of the foundation wall may be thrown
out to within 10 or 12 inches of the bottom of the
concrete.

In building this type of silo it is necessary to erect
on the inside a scaffold of at least four platforms be-
fore any other work can be done. It is very important
that this scaffold be so constructed that the plank run-
ways of the four platforms shall be at a uniform dis-
tance from the wall of the silo. In silos 14 feet or
greater in diameter, a six-legged scaffold is used. For
a 12-foot silo a scaffold of only four legs is needed. In
order to place this scaffold properly there should be
marked on the floor of the excavation a circle having a
radius 2 feet less than the radius of the silo. The six
legs of the scaffold, granted that a six-legged one is to
be used, should stand on this circle and should be equi-
distant from each other. The distance will be equal
to the radius of the circle upon which they stand; the
sweep used in marking this circle may therefore be
used as a measure, marking the place for each leg to
stand on the circle until the six points are located. It
will be much more convenient to have the door open-
ing of the silo come between two legs of the scaffold
than directly opposite one.

All the crosspieces should be of 2x4 material and of
such length as to extend at least a foot outside the

104 Concrete Silos

legs of the scaffold. The planks to form the runway
on the outside should be of 2x8 material, and in a silo
16 feet in diameter should be 8 feet long. If the silo
is to be 36 or 37 feet high, it will be necessary to make
five platforms. It is convenient to have the top plat-
form come within 3 or 4 feet of the top of the silo, since
the work of raising the 2x4's and nailing the plate on
top is done from this platform.

The following table shows dimensions of plate seg-
ments and number required for silos of different sizes :

Inside
diameter of

silo

12 feet
14 feet
16 feet
]8 feet

The plate is sawed from Ix6-inch material, which
should be either fir or cypress. The plan of making
the pattern is shown in the plate. A piece of the 6-inch
board should be securely fastened to a work bench or
barn floor,
and after the U V B /

Dimensions

No. of

of segment

segments

Radius

C. D.

required

2 ft., 10 1/2 in.

26

6 feet

3 ft., 4 1/5 in.

26

7 feet

3 ft., 10 in.

26

8 feet

3 ft., 9 in.

30

9 feet

distance C-D JLUu-^"
has been de-
t e r m i n e d
from the

table, these Detail of Plate.

points should Be carefully marked upon one edge of the
board. Locate the center of the desired curve by the
use of a sweep, through which two small nails have been
driven, the distance between them being exactly the in-
side radius of the silo. Using C and D as centers, de-
scribe intersecting arcs, thus locating the desired center.
Drive one nail of the sweep at the intersection of these

Concrete Silos 105

arcs. With the other nail mark the curve on the 1x6-
inch board. With a straight-edge, extend the radius
across the board, locating the lines at ends of board for
sawing off, as shown by dotted lines in the plate. This
pattern should be carefully sawed out and used in
marking out the rest of the segments necessary. These
plate pieces are to be doubled and the joints broken as
the plate is built up.

In order to cast the posts or door jambs for the con-
tinuous door opening used in this type of silo and to
properly hold the reinforcing in place, a form must be
constructed extending the full height of the silo above
the foundation. One of the plates gives the details of
construction of this form. The 6-inch boards should be
scribed the full length, 1% inches from the outside
edge. Beginning at the bottom, the points for the rods
should be located 26 inches apart on this line. Holes
should be bored at each one of these points with a bit
1/16-inch larger than the size of the rods to be used.
These 6-inch boards are then ripped apart upon this
line.

The next step is to nail together the 8-inch board
C and the wider part of the 6-inch board A. Five or
six pieces of 6-inch board (E in the plate), should now
be sawed and nailed to the underside of the 8-inch
boards, care being taken that the two sides of the
form are squared with each other before these boards
are nailed into place. To insure a uniform distance
between the posts when the form is completed a gauge
18 inches long should be prepared and used between
the two halves of the form during this nailing. The
2x2 's, which have been dressed out and sawed the
proper length, may now be securely nailed in the

106

Concrete Silos

i -E

corners of these two boxes, care being taken that the

bevel is laid in the right direction. The rods, which

should be of %-

inch iron and 32

inches long,

with a 2-inch

right angle

turned at each

end, can now be

placed in the

holes, and the

narrow strip

which was

ripped off can

be cleated back

into place. A

cleat should be

used at each rod

and should be

carefully nailed

with 4-penny

nails. The 2x4 's

(H in the plate),

which have

been spliced together to a length of exactly 30 feet,

may now be placed in the form, to which they may be

fastened by means of boards across the front. These

2x4 's should be gauged out 7 inches from board A.

The door form is now ready to be raised into place.
When it has been raised to a vertical position, it should
be lifted up high enough so that the 8-inch board can
be let down on the inside of the metal lath already in
place. The 2x4's should rest squarely on the founda-

ELEVATION

r

// tf

L

DETAIL OF "A"

SECTION

Detail of Door Frame.

Concrete Silos 107

tion and against the lath on the outside. This form
must now be carefully plumbed and held in place by
short braces to the posts and planking of the scaf-
fold. All braces must be nailed to the form on the
inside so as not to interfere with the subsequent plac-
ing of the metal lath or other material.

The 2x4 studding should be prepared for raising
by being spliced together to a length exactly of 30
feet, or the exact height of the silo above the founda-
tion. The splice may be made by lapping the ends and
nailing them together with three 16-penny nails.

The plate pieces, which have been sawed out in
accordance with the figures given, should now be
hoisted to the top of the platform of the scaffold. Light
gauges should be prepared for use in space the 2x4 's.
It is a good plan to have the gauge used on the top
platform notched at one end so that it may be used in
placing the inner edge of the 2x4 2 inches out from
the inner edge of the plate.

In raising the studding to place, begin operations
by taking one of the plate pieces and nailing it across
the top of the door form, which is already in place, the
inside edge being placed 2 inches in from the edge of
the 2x4 's. A single 8-penny nail driven into the top
of each 2x4 is sufficient to hold this in place. Now
build out two or three sections of the plate, breaking
joints and doubling, securely nailing together the two
layers with 6-penny nails. In raising the 2x4 's, a light
line is a great convenience, one end of it being made
fast to the top end of the 2x4's with a timber hitch, so
that one of the men on top can pull the stick up, while
the man below carries the foot toward the scaffold
and sets it in the proper place on the foundation. This

108

Concrete Silos

2x4 should be spaced out the proper distance from the
2 x 4 of the door form, also out 2 inches from the inside
edge of the
plate; a 16-
penny nail
should be
driven into it
through the
plate. Raise
the next 2x4
in like man-
ner, building
the plate on
ahead two or
three sections
at a time. As
soon as three
or four 2x4 's
are in place,
a p ie c e of
light mate-
rial, such as
ordinary
weather-
boarding,
should be
bent to the
form of a
hoop and

nailed to each 2x4, 4 or 5 feet above the foundation,
with a 4-penny nail, spacing the studding with the same
length of gauge as has been used at the top.

These strips of weather boarding should be ex-
tended as the 2x4 's are set until circle is completed.

Raising- the Door Form.

Concrete Silos 109

Since the door form is carefully plumbed before
one begins to raise the 2x4 's, little difficulty is experi-
enced, as a rule, in having the whole structure stand
perpendicular when the circle is complete. In order
to have the segments of the plate unite properly, it
will probably be necessary to loosen the braces, which
were nailed on top before the circle was complete.
After the parts of the plate have been brought to-
gether the braces should again be nailed in place, so
that the scaffold and the studding may be securely
tied together. A second hoop should be placed around
the silo about halfway down from the top; and if the
2x4 's are very crooked and badly out of line, it may
be necessary to place still another hoop.

The pieces of gas-pipe, which have previously been
cut to the right length, should now be placed in each
door box and wired to the ends of the rods across the
door form.

The 24-gauge expanded metal or metal lath is used
in the construction of this silo. It comes in bundles,
each bundle usually containing nine strips, 8 feet long
and 18 inches wide. A bundle of this size contains 12
square yards and weighs 40^ pounds. This metal lath
is tacked to the inside of the studding with double-
pointed tacks. The work of placing it should begin at
the top, starting at the door post. The end of the
first strip should be passed through the opening in the
side of the door box and bent around the gas-pipe
already in place. Each strip of lath should be tacked first
in the middle ; the workman should go from that place
toward the end, and should, as the tacks are driven,
push out the lath so that it naturally takes the form of

110

Concrete Silos

the circle.
The end of
the second
piece should
be lapped at
least 3 inches
on the piece
already
placed. So
continue un-
til the gas-
pipe on the
other side of
the door is
reached. A
good pair of
snips will be
necessary in
all this work,
since there is
considerab 1 e
cutting of
lath. Where
the ends of
lath pass the
hooks of the
rods across

the door it will be necessary to split the end back
about 4 inches, so that it can be bent around the gas-
pipe properly. It is very important that the end pass-
ing around the gas-pipe be long enough to encircle it
completely. Two workmen are needed to do this work
to good advantage, and more men can be used if they

Placing Door Frame Reinforcement

Concrete Silos 111

are available. The different rounds of the lath should
lap from % to % inch, and in case any bagging is seen
the edges must be wired together with light wire. This
will prevent a great deal of annoyance to the plasterers
in placing the first coat of plaster. Whenever it be-
comes necessary to splice the ends between studding,
the splices must be carefully wired together. When
the ends are spliced on the studding and lapped 3
inches, this wiring is not necessary. This expanded
metal lath has a right and a wrong side, and the best
results are secured if the material is so placed that the
slant of the mesh is upward when looked at from the
inside. If, when the bottom is reached, the lath does
not come out even, which is usually the case, the last
round may be left full width in case there is enough
lath to allow this. Care taken in getting this lath
smoothly placed and carefully wired will mean the
saving of money later, since the plasterers can make
better headway where this work has been properly
done.

Although the first silos of this type contained no
other reinforcement than the metal lath, it has since
been thought desirable to place additional horizontal
reinforcement in the form of strands of heavy wire
completely encircling the silo. These wire strands
cannot be placed until all of the inside plastering is
done and the studding is removed. Provision must be
made, however, for their attachment to the vertical re-
inforcement in the door post before any mortar is
placed.

Means of attachment at the doors can be most easily
provided for by fastening short wire loops to the gas-

112 Concrete Silos

pipe in the door post. A 16-foot silo, 30 feet high,
should have at least 150 pounds of additional wire
reinforcement. Since the pressure is much greater at
the bottom, gradually decreasing toward the top of the
silo, a larger amount of the wire should be placed in
the lower part of the wall. The table shows the cor-
rect spacing of the wires in a 16-foot silo below. The
loops attached to the gas-pipe to which these wire
strands are later to be fastened should be placed in
accordance with this table, and may be put in place
at the time at which the lath is being tacked to the
studding, or just before the plastering begins.

Table showing proper spacing of extra wire reinforcement for
silo 16 feet in diameter.

Feet from top Number of strands of

of silo No. 9 wire required.

0- 4 1 strand for every 24 inches.

4- 8 1 strand for every 24 inches.

8-12 1 strand for every 24 inches.

12-16 1 strand for every 12 inches.

16-20 2 strands for every 12 inches.

20-24 2 strands for every Sy2 inches.

24-28 2 strands for every 6 % inches.

28-32 2 strands for every 5 inches.

32-36 2 strands for every 4 inches.

Silos of larger size will require one additional
strand of No. 9 wire for every 2 foot increase in
diameter.

After the metal lath and the wire loops are in place,
the thin boards, K, should be nailed in place, care being
taken to press the edge as tightly as possible against
the lath, since this box is to be later filled with mor-
tar. Plenty of nails should be used to hold these
boards, but the heads should be left slightly out so
that they may easily be drawn later. If this precau-
tion is not taken, some difficulty may be experienced
in removing this board when the proper time comes.

Concrete Silos

113

Bolts are used to secure the plate to the finished
wall of the silo, and these must be in place before the
plastering be-
gins. Then
%-inch bolts
10 inches
long will be
sufficient for
silos not ex-
ceeding 1 6
feet in diam-
eter. Holes
should be
bored in the
plate and
should be
spaced at as
nearly equal
distances
apart as pos-
s i b 1 e. The
bolts should
be supplied
with washers
and should

be passed
through the
plate from

Applying the First Coat of Plaster to the Inside.

below, and the nuts put on. The bolts should hang
down below the plate just inside the metal lath so as
to be covered by the first coat of plaster.

It is almost necessary to have a chute on the silo,
and provision should be made for attaching this chute

114 Concrete Silos

by placing five or six bolts % inch by 4 inches in a
perpendicular line 3 or 4 inches outside of the door
post. These bolts may be passed through the metal
lath with the nuts on the outside. As the plastering
progresses, care should be taken that the bolts are
made to project perpendicularly from the wall.

The mixture for the scratch coat consists of 1 part
of cement, 2% parts of sand, and 10 per cent as much
hydrated lime as cement. About 1 bushel of hair to
every 300 square feet of surface to be covered must be
used in this first coat. For the plastering of a silo 16
by 30 feet, about 7 sacks of hydrated lime and 5 bush-
els of hair will be required. The lime should be soaked
up 10 or 12 hours before it is to be used. The hair
should be thoroughly beaten part on a barn floor, and
after being soaked several hours should be carefully
picked to pieces and worked into the lime putty which
has been prepared. If care is used, the hair will be
thoroughly mixed with the lime and the mixture can
be added to each batch of the cement mortar as it is
being prepared for use. It will take about 1% pailfuls
to each 2 bag batch of mortar. It will be well for the
plasterer to make some estimate as to the right amount
of this to use in each batch, so as to have enough to
use for the whole scratch-coat. This coat will require
about 13 two-bag batches of mortar for 16x30 foot
silo.

Two good plasterers will be required, and four
tenders, two to measure materials and mix the mortar,
one to carry and elevate it to the proper platform, and
the fourth to receive the mortar on the platform and
place it on the mortar-boards. This last man should
do all the moving and shifting work, so that the plas-
terers may not be delayed at any time.

Concrete Silos 115

Sometime during the process of applying the
scratch coat, the space under the door should have been
cased up inside and out and filled with mortar mixed
in the proportion of 1 part of cement to 2l/2 parts of
sand. A strip of wood should be placed across the bot-
tom so that the shoulder which is cast at the side of
the doors will be continued across the bottom of the
door.

When the scratch coat is all on, the door posts are
to be filled. Since the 8-inch boards forming the in-
side of the form have a tendency to spring back under
the weight of the mortar, some provision must be made
to hold these boards rigidly in place. This can easily
be accomplished by firmly nailing short braces to the
scaffold plank at each platform, the ends being braced
solidly against the back of the form.

If this work can be completed by quitting time at
night, or even by working overtime, the thin boards
on the inside can be removed the next morning. Con-
siderable care must be used in removing these boards,
since the mortar will be rather green and easily in-
jured. The placing of the remaining layers of plaster
can now proceed with no further delay.

The mixture for the second layer of plaster should
consist of 1 part of cement to 2% parts of sand, and
should be applied in three coats, giving a total thick-
ness, including the scratch-coat of at least 1% inches.
In applying these coats, begin at the top and work
down, one coat following the other as rapidly as pos-
sible. An old broom should be kept on the scaffold,
and the helper should rough up each coat as soon as it
has wet sufficiently, so that succeeding coats will not
be applied to the glossy surface left by the trowel. It

116 Concrete Silos

is necessary at all times to keep water upon tlie scaffold,
since many times the work will dry too rapidly and it
will become necessary to sprinkle the wall before the
next coat of plaster is applied.

Before applying the last layer of plaster to the in-
side, the inner part of the door form should be removed.
With this form- out of the way, the finish coat, consist-
ing of equal parts of cement and screened sand, may be
smoothly applied in such a manner as to leave the in-
side surface flush with the face of the door post. The
use of water is very important during the application
of this coat. A force pump, preferably a pump run by
a gasoline engine and a line of hose, is a great con-
venience in keeping the walls thoroughly wet.

The finish coat should be smoothed up neatly. When
it has sufficiently set, one of the plasterers should mix
up a wash of pure cement and give it what is commonly
called a "slush coat." It should be the aim of the
plasterer to finish this coat and have it set without the
appearance of checks of any kind. This coat should
extend down upon the foundation wall to the bottom
of the silo.

Under ordinary conditions, by the time the inside
is finished, the wall, which is now 2 inches thick, has
set sufficiently to permit the removal the outside stud-
ding and parts of the door form still in place. The
inside scaffold should be removed also; one should
begin at the top and pass the material out through the
door opening. The first step in taking down the tem-
porary studding is to remove all the hooping material.
When the foot is forced loose, the 2x4 may be pulled
out straight from the silo until it is free except for the
nail at the top. By pulling down on the stick, one may
detach it from this nail and lay it on the ground. It

Concrete Silos

117

is a good plan to determine the number of legs neces-
sary for the outside scaffold before removing these
studs. By leaving two of them at each point where the
scaffold legs
are to stand,
they can la-
ter be loos-
ened from
the wall and
stood out at
the proper
places, thus
saving the la-
bor of raising
them from
the ground
again while
building the
outside stag-
ing.

Before the
plastering on
the outside is
begun the ex-
tra wire re-
inforcement
should be put
in place.

Pouring the Door Posts.

This wire is
to be a t-

tached to the wire loops which now lie flat on the out-
side of the wall. The number of strands of wire to be
placed at each loop is given in the table. These hoops

118

Concrete Silos

of wire should be passed around the silo and attached
to the loops on the opposite side. Continue this process
until all hoops have bands of wires attached to them.

The lumber
used for the inside
scaffold is to be
used in building a
scaffold on the
outside, the 30-
foot 2x4 's left in
place being used
for the legs of the
scaffold. Care
must be taken that
the inside legs and
the plank runway
of this scaffold are
at such a distance
from the wall of
the silo as will be
convenient for the.
plasterers to work.

The outside
layer of plaster
should be at least
1 inch in thickness
and should be ap-
plied in 2 coats,
using one part of
cement to 2%
parts of sand. The use of the darby on the last out-
side coat will add to the appearance of the silo. A
float finish gives a pleasing appearance to the outside.

HORIZONTAL SLCTIQN CF WALL AT DOOR,.

Concrete Silos 119

The use of a wash coat of pure cement as a final finish
will also greatly improve looks of the silo. The walls
should be thoroughly wet before this coat is applied.

The finished silo should be wet thoroughly once
daily for at least a week after the job is complete. The
use of water is a very important factor in the securing
of a good concrete job built above ground, since the
constant tendency is for the material to dry before
proper setting can take place.

The same type of doors described for use in the
solid-wall silo with continuous door opening can be
used in this silo.

In order to provide against freezing of silage in se-
verely cold climates, a double-wall metal-lath silo has
been developed, as illustrated herewith. The sill
is made of 2-foot lengths of 2x4 's imbedded in
the concrete foundation. The studding
are 2x4 's spliced to the proper lengths
as outlined for the temporary
studding used in construct-
ing the single wall metal
lath silo. T h e s

Roof for Metal Lath Silo.

studding are set on the sill and are toe-nailed to it.
On each side of the door opening are set two 2x4 's
spiked together to form 4x4 's for the door frame.

120

Concrete Silos

These are bolted together across the opening by % inch
rods. A jamb for the doors to fit against is formed by
sawing a 2x4 as outlined previously in this chapter.
The plate at the top of the silo is made the same as for
a single wall silo. After the frame has been completed
metal lath is stapled to both the inside and outside of

Concrete Silo for Walker Bros., Walkerville, Ont.

Note the attractive appearance of permanent Concrete Silo (at
left) compared with wood silo (at right) which is already showing
signs of deterioration.

00

132
of
132

Yds.
h
Ft
ire

of L
66 Li
No. 1

20 Sq. Yds.
of Lath
Wire reinforc
ent required

"AS*

Wire reinforce
ent required

156 Sq. Yds.
of Lath
276 Lin. Ft
No. 8 Wire

38 q ds.
ofLath
58 Lin. Ft
No. 8 Wire

*Jl4

132
ofL
o Wire r
ment requ

**£•*
^1 d*

^°°
S°S5

ilki!^

96 Sq. Yds.
ofLath
No Wire reinfo

ment req

i*

114 Sq.
ofLath

racnt required

-

74 q. Yds.
of Lath
20 Lin. Ft
. 8 Wire

Sq. Yds.
of Lath
30 Lin. Ft
o. 8 Wire

£ gS5 2 S55

£•$*-.£ Z-S^t

£^

50 Sq.
of Lath
60 Lin. Ft
No. 8 Wire

180 Sq. Yds.
of Lath
877 Lin. Ft
No. 8 Wire

2 8*

•

S

ds.
h
Ft
ire

Y
th

Sq.
f La
Lin.
. 8 W

252 ds.
of Lath
3360 Lin. Ft.
No. 8 Wire

. ds.
of Lath
950 Lin. Ft
No. 8 Wire

228 q. ds.
of Lath
2720 Lin. Ft
No. 8 Wire

98 Sq. Yds.
of Lath
560 Lin. Ft
No. 8 Wire

8

332 Sq. Y
ofLath
6708 Lin. Ft
No. 8 Wire

336 Sq. Y
ofLath
9460 Lin. Ft
No. 8 Wire

Sq. Yds.
l Lath
Lin. Ft
8 Wire

00 Sq. Yds.

6850 Lin. Ft
No. 8 Wire

a

LtfjW ^e

•«•£ -'£<><-S -i*

a^ra=

384 ds.
ofLath
7275 Lin. Ft
inch

3 12 Sq. Yds.
ofLath
4725 Lin. Ft
X inch Rods

Sq. Yd
f Lath

324 Sq.
of L
4000 Li
Y4 inch

336 Sq. Yds.
of Lath
5050 Lin. Ft
y4 inch

Sq. ds.
f Lath
3280 Lin. Ft
Y\ inch Rods

Sq. Yds.
of Lath
4175 Lin. Ft
yt inch

264 Sq. Yds.
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2090 Lin. Ft
X inch R

Sq. Yds.
of Lath
3400 Lin. Ft
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ds.
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i«gi

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S

56 Sq. ds.
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110 Lin. Ft
No. 8 Wire

Jfl

84 Sq. Yds.
ofLath
No Wire reinforce-
ment required

96 Sq. Yds.
ofLath
Wire reinfor
ent require

Yds.
th
inforc
uired

3 •*!"-*

Mil

S3'^

f^ia

62 Sq. Yds.
of Lath
520 Lin. Ft
No. 8 Wire

180 Sq. Yds.
of Lath
857 Lm. Ft
No. 8 Wire

82 Sq. Yds.
of Lath
405 Lin. Ft
No. 8 Wire

Sq. Yds.
of Lath
620 Lin. Ft
No. 8 Wire

W'

«2.

s 2:

. ds.
Lath
Lin. Ft
ire

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W

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945

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X

(121)

122

Concrete Silos

the studding, placed with the long dimension around
the silo.

In estimating the quantity of metal lath required for
a double wall silo, the table given in this chapter can
be used, remembering to use just twice the amounts.

Silos are also made from the various special pat-
ented types of metal lath now on the market. With
some of these it is found to be possible to erect the
silo without the use of the temporary studding previ-
ously described.

One such is the product known as Hy-Rib, made by
the Trussed Concrete Steel Company, Youngstown, 0.
This is a herringbone metal lath with deep corrugations
or ribs pressed in it at regular intervals, these giving

Hy-Rib Acts As a Form and Reinforcement for the Concrete.
Note the temporary wood frame for metal sheets. If the
wood frame-work is to be removed the sheets must be wired
together. If 2x4-inch rafters are to be left the metal may be
nailed lightly to them and the cross boards only removed.
This is undoubtedly the quickest and cheapest method.

Concrete Silos 123

it strength and stability. The type usually recom-
mended for silos is made from 24 gauge metal, has the
ribs 4 inches apart and 15/16 inch high, and comes in
sheets 24 inches wide and 10 and 12 feet long. For
silo work these sheets are curved at the mill to the de-
sired radius. These sheets can either extend down into
the foundation, as shown in the illustration, or can
begin at the top of the foundation. In the latter case
dowel pins are set in the foundation, and allowed to
extend several inches above it, for attaching the first
ring of Hy-Rib. The construction as shown in the illus-
tration is recommended, however, carrying the metal
down to the footings.

It will be noted also that rib bars are used to give
stability to the walls while being plastered. These are
% inch ribs, wired to the metal sheets, and left in as
a permanent part of the silo. Plaster is applied on both
sides of the metal to a total thickness of 3 or 3% inches.

In this type of construction the builder may erect
the metal to a height of 30 feet before beginning to
plaster, or he may erect it in sections and plaster, as
desired. After any plastering is done, however, it will
require at least a half day to harden before any more
metal is placed.

The roof of a Hy-Rib concrete silo may be of a cone
shape, a dome shape, or an octagonal hip, which are all
constructed of Hy-Rib covered with 2 inches of con-
crete, back-plastered underneath. The chute may be
built in connection with the side walls using Hy-Rib of
any desired size, thereby making the chute, side walls
and roof of silo one complete unit with the foundation.

A silo similar to the above is made by the use of
Trusridge expanded metal, made by the Edwards
Metal Structures Company, Kansas City, Mo. In this

124 Concrete Silos

case, however, %-inch pipe is used for studs, to which
the metal is wired. The pipes are furnished in 10 and
12-foot lengths, threaded for unions, and are held in
place by a ring of angle iron which has holes punched
in it for the pipes. This ring holds the pipes to a true
circle.

CHAPTER XV
THE CONCRETE STAVE SILO

The concrete stave silo is patterned after the wood
stave silo, and has been developed in an attempt to
introduce some of the elements of ease of erection and
low cost of the wood silo, combining with them the
features so desirable in concrete.

These silos are built up of members resembling
staves, and erected and held together in the same
manner. It would manifestly be impossible, however,
to make them in such lengths as are handled in wood,
so that the length of the concrete staves is limited
usually to 28 or 30 inches. They may be either made
on the job, or shop-cast and moved to the place of erec-
tion. In this latter case they can usually be cured
under better conditions and there will not be the dan-
ger of hurrying them into the structure before the
proper curing has taken place. These staves are usu-
ally poured of slush concrete in multiple steel molds.

The staves are generally made in a width of about
10 inches and are cast flat. The usual thickness is
about 2% inches. All types have some method of giv-
ing the staves a vertical joint, and some of them also
provide a horizontal joint where the ends of the staves
come together. The joints are filled with mortar. To
still further safeguard the structure against air and
moisture, the inside may be plastered or given a wash
coat of cement.

In constructing the silo the staves are assembled
with staggered joints, the first row of staves consist-
ing of alternate full length and half length staves.

(125)

126

Concrete Silos

These silos are
held together by out-
side hoops, as is the
case with wood
staves, the hoops be-
ing placed closer to-
gether at the bottom
to provide for the
greater strain, the
spacing being gradu-
ally increased as the
top is approached.

Some of the com-
mercial stave silo
systems now on the
market are described
in the following
pages.

Many of these
silos have been built
on the foundations
of old wood stave
silos and are giving
excellent satisfac-
tion, a point which
is worth while re-
membering in pro-
moting the sale of
these silos. The
foundation for the
stave silo is made
the same as for other
types.

Perfection Stave Silo on State Fair
Grounds at Des Moines, la. Diameter
14 feet 4 inches ; height 44 feet 4
inches ; capacity 194 tons.

Concrete Silos

127

Perfection Concrete Stave Silo. This system is
controlled by the Perfection Concrete Stave Silo Com-
pany, Des Moines, Iowa, and the outfit with which
the staves are made is sold outright to manufacturers.
These staves can be used for structures from 10 to
36 feet in diameter and up to 60 feet high.

The staves are 28 inches long, 10 inches wide, 2%
inches in thickness, and are made in steel forms with
a wet mix, waterproofed and made impervious by the
addition of 10 per cent of the weight of cement in
hydrated lime. The staves are made concave on the
edges and on the ends, and when they are assembled
in the silo the space which is thus formed is filled with
mortar.

The company also manufactures for use on its silos
a malleable iron door frame and an all-steel door with
steel ladder combina-
tion. The door sys-
tem is continuous
from the foundation
to roof, the frame
occupying a space of
only 4 inches between
doors. Each door
opening is 23x25 in.

In Constructing the

silo, one of the malle-

able iron door frames

is placed upon a circular concrete foundation, and half

staves (that is, 14 inches in length by 10 inches in

width by 2% inches in thickness), are plaped on the

foundation, in the channel on either side of the

malleable iron door frame; then a full length stave is

The Perfec Silo Steel Door in

steel ladder sys"

128 Concrete Silos

stood up by the side of each half stave, and the circle
is completed by alternate half and whole staves.
Thereafter, whole staves are used until the top of the
silo is reached, when half staves are used to fill out
the top, alternately between the full staves.

On completion of the first circle, two bands are
placed around the circle, one 2 inches above the foun-
dation and another half band is placed 14 inches above
the foundation, and the end of the half band is placed
in the lugs on either side of the door and turned up
even with the end of the rod.

As each course is erected and put into place, the
concavity between staves is filled with mortar, con-
sisting of 1 part cement, to 3 parts of screened sand,
and the ends of the staves as they meet are also filled
with mortar, so that when the silo is completed every
joint is filled, thus preventing any escape of the silage
juices or admission of air into the silo.

Suitable collapsible staging is erected on the in-
side of the silo as the walls are being extended upward.

As soon as the silo walls are completed, a water-
proofing composition is placed upon the inside wall
by brush applications.

In this system the contractor is supplied with steel
molds sufficient to cast 200 staves or more a day. The
supposition is that the contractor will haul his molds
to the farm, or the place where the silo is to be "built,
and that the owner will provide the materials ready
for working. The contractor will then send two ex-
perienced men to cast the staves. The manufacturers
state that it will require 900 staves to build a, silo 16
feet in diameter by 35 feet high, holding 150 tons of

Concrete Silos

129

silage. The two men it is stated will cast these in 4%
days. They are then left 4 or 5 days to cure before
being erected.

Playford Cement Stave Silo. This system is con-
trolled by the Cement Stave Silo Company, Des Moines,
Iowa. These staves are made 30 inches long, 10 inches
wide and 2% inches thick. One edge is concave and
the other convex, so that the staves fit closely to-
gether, no matter what the radius of the silo and the
consequent curvature of the walls. In building a Play-

Playford Silo With Door Spreaders

Chute.

ford Silo the first row consists of alternate full and
half length staves; thus the joints are broken the
entire way up, and the last row finished with alter-
nate full and half lengths. These silos when erected
are held together with hoops of round steel joined
with patent lugs. These hoops are put on as the silo

130

Concrete Silos

goes up, so that the structure is held perfectly rigid
at every stage of construction. Alternate hoops en-
tirely encircle the silo, when the intermediate hoops
fasten to door spreaders, these passing around the

The Playford Cement Stave

door openings and leaving them unobstructed. A
combination sectional ladder and chute is also pro-
vided. After erection the silo is treated with a special
waterproof filler coating on the inside.

Reinforced Stave Silo. This stave, which is con-
trolled by the Playford Manufacturing Company of

FOR Poirmwa

Reinforced Stave Silo

Elgin, Illinois, carries an outside vertical rib on one
edge through which passes a a/4-inch twisted reinforc-
ing bar. The thickness through the stave proper is

Playford Cement Stave Silo.
(131)

132

Concrete Silos

21/4 inches while the thickness through the rib is 4%
inches. The stave is 12 inches wide and 30 inches
long.

Each stave carries a lug on top with a correspond-
ing recess in the bottom, forming a lock for the lateral
joints. A concave and convex joint on the sides of

Method of Assembling Reinforced Silo Staves

the slabs is so designed that space is allowed for
pointing up on the outside after the silo is erected.
The silo is also given a cement wash on the inside, giv-
ing it a double seal.

The ribs on the outside of the staves carry prop-
erly spaced depressions for receiving the hoops, so

Reinforced Stave Silo
(133)

134 Concrete Silos

that the latter cannot slip out of place. The hoops,
being held out from the face of the silo by the ribs,
form a convenient ladder for climbing up the silo at
any point.

A continuous door system is provided for, special
staves being made for the door opening which carry
an offset against which the door can rest and also
having recesses into which a casting can be slipped
as a dividing plate between doors. This casting is
held firmly in place automatically when both the up-
per and lower staves are in position. The doors are
of wood, held in place by latches which are turned
over the flange of the castings above and below.

A galvanized iron roof is usually put on, with a
chute either of that material or built up of the staves
themselves.

The staves iare poured of a slush mixture in in-
dividual molds of sheet steel and are allowed to re-
main in the molds for 24 hours.

Interlocking Cement Stave Silo. This system, con-
trolled by the Interlocking Cement Stave Silo Com-
pany, Des Moines, Iowa, has as its most noticeable
feature a bevel on the ends of each stave. This irregu-
lar form of joint makes it possible for a single band
passing around the joint to hold the ends of all staves
— both those ajbove and those below. Concave and
convex edges also provide an additional interlock.

The staves are 28 inches long, 10 inches wide and
2% inches thick. The company makes two types of
equipment for the manufacturing of these staves, one of
them adapted to the manufacture of small and inter-
mittent lots of staves, and tKe other a larger outfit for
making larger quantities. Both make identically the
same design of product.

Concrete Silos

135

The first mentioned is a hand mold, open at top
and bottom and designed to rest on a pallet and be
withdrawn after the concrete is
tamped in and struck off; the
other is a machine somewhat
similar to a concrete block or
brick machine, in which the
operations are done more rap-
idly by mechanical means.
Both outfits are provided with
means for making fractional
staves as needed.

A mold for casting a sec-
tional concrete door frame is
also a part of each outfit. This
door frame is the same height
as a stave, 28 inches, and 40
inches wide, taking the place
of four staves; it also is pro-
vided with one concave and
one convex edge to fit into
adjoining staves. It thus can
be used continuously or inter-
mittently as desired. The door
frame has an opening of 28x20 inches, with an offset
to accommodate a wood door.

Swan Stave System. This design of stave was orig-
inated by the Swan Concrete Stave Silo Company,
Cassopolis, Michigan. It is a dry tamp stave made in
a simple form on wood pallets, the pallets being curved
to the radius of the silo. The staves are dovetailed
on the ends and each stave also has a tongue on one
side and top and a groove on the other side and the

Interlocking Cement
Staves.

136

Concrete Silos

bottom. The staves
are 30 inches long,
10% inches wide,
and 2l/2 inches thick.
Supreme Silo. The
patent on this silo is
held by J. A. Brod-
erick, of Marshall-
town, Iowa. It is
built with either a
single or double Swan stave Sil°

wall, the former being recommended for warmer cli-
mates and the latter for colder. The distinctive fea-

A Plant Manufacturing- Swan Staves

ture of this system is a concrete band or rib which is
cast around the silo after the slabs are laid up, one of
these being placed at each joint and serving to cover
the reinforcing as well as cover the joint between the

Concrete Silos 137

ends of the slabs. In order to accomplish this result
the slabs are laid up with even lateral joints and stag-
gered vertical joints, just the opposite of the general
custom in stave construction. The concrete ribs, being
carried completely around the structure, also form sills
and lintels for the door frames where they cross the
door openings.

Everlasting Silo Staves. W. W. Rohrer & Son of
Orrville, Ohio, have a system of silo stave manufacture
to make staves 24 inches long, 10 inches wide and 3
inches thick. One vertical edge of each stave is con-
cave and the other convex, making a perfect joint.
Half length staves are used in starting the silo, so that
joints are broken all the way up. The staves are held
together with %-inch iron rods with patent knuckles.
As each row of staves is placed in position the hoop is
placed around and drawn up tight, each band passing
around the middle of half the staves and the ends of
the intermediate ones.

It is claimed that a special mixture is used in mak-
ing these staves, rendering them impervious to mois-
ture and also acid probf.

Panel Silos. These can perhaps best be included
under the general heading of stave silos, although in
this case the units run horizontally instead of ver-
tically. This system is controlled by the Concrete
Panel Silo Company of Kansas City, Missouri. It con-
sists of poured concrete columns alternating with pre-
cast concrete slabs. The slabs are 10 inches high, 24
inches long, and 3 inches thick.

In erecting the silo, the slabs are first laid up to a
convenient height, with reinforcing rods in the hori-

138 Concrete Silos

zontal mortar joints between courses. The ends of the
slabs have an outside bevel, leaving a considerable out-
side opening between the ends. Against this opening
a steel form is erected and poured full of concrete,
thus closing up the joint, and making a column to
add to the stability of the structure. This column is
reinforced with a %-inch vertical rod. Intermittent

Diamond Stave Silo

door openings are made by omitting three panels at
suitable intervals in one tier.

Diamond Concrete Stave Silo. This system is sold
by the Diamond Concrete Stave Silo Company, Kan-
sas City, Mo. These staves are diamond shaped, inter-
locking with tongue and groove, and held together
by either round rods or bands. They are 30 inches

Concrete Silos 139

long, 11% inches wide at the middle and 6 inches at
the ends. A notable feature of the staves is that they
are thicker in the center than at the edges, the center
thickness being 3 inches and at the edges 2% inches.
This provision is made to give the finished silo an
outside curvature, allowing the bands to fit more
snugly instead of resting only on the edges of the
staves.

CHAPTER XVI
CONCKETE BLOCK SILOS

The concrete block silo, if well made, has at least
two advantages to recommend it: It is usually made
of hollow blocks, thus providing an air space in the
wall which will help to insulate the contents against
frost and moisture; and if some care is taken in the
design and construction, it can be given a more decora-
tive appearance than is customary with the general
run of farm structures.

On the other hand there are certain precautions
which must be taken in putting up this kind of a silo.
Most of the silo block systems provide for a dry or
semi-dry tamp block. With such a block it is of the
utmost importance that the materials be properly se-
lected, graded and mixed, and the manufacturing and
curing be done in the most approved manner, else the
block will not have sufficient density to make it mois-
ture proof. It is worth while, therefore, to urge upon
block manufacturers the extreme importance of put-
ting the best quality of materials and workmanship
into silo blocks ; and also to urge upon owners that
they give careful attention to the blocks they are get-
ting, contracting for them only with manufacturers
who have the best reputation.

For the manufacture of silo blocks a clean, well
graded sand should be used, and the mixture should
be 1 part cement to 3 parts sand. The mix should
be made as wet as the molds will lallow, and should
preferably be cured by steam, taking care that the

(140)

Concrete Silos

141

blocks are not allowed to dry out before having the
steam turned on them. Additional waterproofness can
be secured, if necessary, by the addition of some good
waterproofing substance to the concrete when it is
made, or by the application of an inside or outside

Two Decorative Silos of Ideal Blocks on the Barber Estate,
Barberton, Ohio

coating, or both. A coat of cement plaster on the
inside will be conducive to this end, and will also have
the advantage of giving the silo a smooth wall.

In starting the construction of a concrete block
silo, the excavation, floor and footings will be the same

142 Concrete Silos

as for a monolithic silo. In starting the walls, however,
some readjustment of the radius may be necessary in
order to accommodate the construction to the size of
units available. The length of silo blocks is not usu-
ally changed for the various diameters, so that in order
to make it possible to use only whole and half blocks,
or such fractions as the machine will make, and thus
avoid cutting, it will be well to lay out a test circle
after the footings are in and see how closely the blocks
conform to the desired size. The circle can then be
made slightly larger or smaller to accommodate them.

The cement mortar should consist of 1 sack of
Portland cement to 2 cubic feet of clean sand, with
the possible addition of a small quantity of hydrated
lime (not over ten per cent), to make it easier to work.
Before laying up the blocks, see that they are thor-
oughly soaked which will prevent them from draw-
ing moisture from the mortar. No more mortar should
be mixed at one time than can be used up within 30
minutes after first moistening.

Most blocks now made for silo work have some
provision for continuous reinforcement; but if such
provision is not made, reinforcing wire must be used
between the courses of blocks. A table herewith gives
the -amounts of reinforcing necessary for block silos.

The doors in a block silo are installed similarly to
those in silos of other types. For intermittent doors,
frames 6 inches wide of 2-inch lumber are placed at
proper intervals in the 8-inch wall. This leaves a 2-
inch recess on the inner surface of the wall in which
will set the wooden door. Vertical steel rods are set
in mortar in airtight spaces of the block next each side
of the doors, and the horizontal reinforcing hooked
around them. Sufficient extra rods are placed across

Concrete Silos

143

Block Silo at Atlanta, 111.

the top and bottom of the door to equal the horizontal
rods which are cut out by the door opening.

For a continuous door, a vertical concrete frame is
sometimes cast on each side of the door opening. In

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Concrete Silos 145

this frame are embedded the vertical rods, to which
all the horizontal rods are hooked, in a manner simi-
lar to that described for monolithic silos. At other
times angle irons or U-bars are used for frames, or
special iron shapes, with offsets for doors are used.

A wooden or metal chute can be fastened to the
walls or one can be built of blocks at the same time as
the walls.

The roof of a block silo can be made either of wood
or of concrete. When of concrete, the method of pro-
cedure is the same as that specified for solid wall silos,
except that the temporary roof rafters rest on the
wall, and the eaves 'are formed 'by a special block
which gives the necessary overhang.

Below are given brief descriptions of a number of
the systems of silo block construction now available.

Hurst System. This system is marketed by the
Hurst Silo Equipment Company of Chicago. The
unit of construction is a solid block 231/2 inches long,
11% inches high, and 4 inches thick. Each block is
reinforced with two %-inch round rods, the ends of
these rods projecting into recesses at the end of each
block and being bent into a hook to receive a steel
link. When the blocks are laid up in the wall, the
ends of rods in adjoining blocks are thus brought to-
gether, and after the link is slipped over them the ends
are bent back by means of a tool supplied for the pur-
pose. This makes the reinforcing continuous around
the structure, and the process of bending up the rods
serves to bring the steel into tension and thus resist
the pressure of the silage when the silo is filled. The
recesses which hold the links are afterwards filled with
mortar, as well as the V-shaped joint between the
blocks on their inside surface.

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Concrete Silos

147

These blocks are cast in steel molds, each mold
making ten blocks at one operation. A reference to
the illustration here shown will give a very good idea
of the assembling of the mold. Each mold consists of
two sides, two sets of division plates, clamps for lock-
ing molds, and core covers. The sides of the mold are
of pressed steel, fitted with hollow pressed steel cores,

Method of Laying up Hurst Blocks

which form the recesses at the ends of the blocks and
which also hold the reinforcing rods in place while the
blocks are poured. The division plates are of %-inch
rolled steel, 24 inches long and the height of the block.
These division plates are curved to conform to the
diameter of the silo and can be furnished for any
size. Short division plates are also supplied for mak-
ing sectional blocks for "fillers." Two sets of stand
ard division plates are furnished with each mold, s»
that it can be filled twice daily, making twenty block?

148 Concrete Silos

A special bender for making the rods and links is
included in the outfit if desired, or these will be fur-
nished by the company to those who do not care to
prepare their own. A bender can also be secured for
changing dividing plates from one radius to another.

Iron or steel door frames are either secured from
the company, or a pattern only is bought, allowing the
contractor to have his frames made at the nearest
foundry. All frames are curved to a radius of 8 feet,
in order to avoid multiplication of parts, as the dif-

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ference of curvature is scarcely noticeable in the width
of a door when this frame is used on other sizes. The
frame provides a beveled rabbet for a wood door, and
carries loops to connect with the reinforcing rods of
the adjoining blocks.

Steps are bolted to the doors, or ladder steps of
steel with ends flattened are embedded in the mortar
between the courses of blocks.

If a chute is desired, %x5-inch bolts are inserted
in every third mortar joint on either side of the door
frames, beginning 8 feet from the ground. Similar

Concrete Silos

149

bolts also extend upward every 4 feet in the joints of
the top course of blocks, to anchor the roof, which
may be of any type.

Dave-tail Silo Block. The Lansing Company, Lan-
sing, Mich., manufacture what is called the Dove-tail
silo block ma-
chine. This ma-
chine makes a
hollow silo block
with dove-tail
openings at each
end. Where these
openings come
together, they fit Dove-tali siio Block,

over a small countersunk hole in the middle of the
block below. The dove-tail opening is filled with soft
mortar which finds its way into the countersunk hole
and binds the blocks together both horizontally and
vertically. A small groove is also provided in the top
of each block for the purpose of laying in reinforcing
wire.

The machine consists of a base and a flask or mould.
The mould consists of a front and back plate, two
end plates, center cores, dove-tail end cores, extra
face plate for half size blocks, and dividing plate. The
two end plates fit into lugs in the front plate and the
back plate is held in position by two end levers. The
mould is of the self-truing type and will produce
blocks of an attractive design. It is furnished in 12,
14, 16 and 18-foot diameters. Each size of block can
also be used for a silo of a diameter 2 feet larger
than the stated size. It is equipped for either 9 or
10-inch blocks, 16 inches long, 8 inches high. The

150

Concrete Silos

regular equipment consists of rock face design, but
the manufacturers also furnish a plain design.

Ideal System. The Ideal Concrete Machinery Com-
pany, Cincinnati, Ohio, supplies molds for silo blocks

Method of Constructing Ideal Silos

Concrete Silos

151

in the standard 8x8x16 inch size in practically all the
faces designed by this company for straight building
blocks. These silo attachments can be set on the
standard Ideal block machine base outfit, and the silo
blocks are cast with two 4x6 inch core openings the
same as the building blocks. Attachments are pro-
vided for making blocks on a 5, 7 or 9-foot radius.

As each block is cast, a piece of half round iron
makes a groove in the top, about 1 inch from the out-
side face, this groove accommodating the reinforcing
ring when the blocks are laid up. These rings are
fastened at the ends to the
door frames as shown in the
illustration ; or if the builder
has at hand the proper dies
for cutting threads, he can
thread the ends of each ring
and draw the ring to the
proper tension with a nut.

The door frames consist of
U-bars for uprights con-
nected at 3-foot intervals by
4-iiich I-beams. The uprights
are set just the thickness of
the door from the inner face
of the block, so that when
the door is in place the inte-
rior will present a smooth
surface.

It is recommended that the climax Blocks

inside of the silo be plastered with cement mortar, ap-
plied, preferably with a trowel, and then going over the
entire surface with a stiff brush and cement grout.

152

Concrete Silos

Climax Silo Blocks. The equipment for making
these blocks is furnished by the Climax Manufactur-
ing Company, Anderson, Indiana. The blocks are 20
inches long, 10 inches high, and 4 inches thick. Each
block carries lugs on the underside and recessed groove
on the upper side, holding the blocks in perfect posi-
tion when they are placed together. The blocks them-
selves are reinforced with any wire available, and a
No. 9 wire is also used in the grooves as the blocks are
laid up.

Kenny System. The
Kenny concrete blocks
are made with a groove
in the top for receiv-
ing the reinforcing
rod, which is contin-
ued in one piece
around the entire silo,
locking it over a key
block, as shown in the
accompanying cut.

The vertical grooves

in the ends Of the Wires Locked Over Key Block

blocks form an opening 2 inches in diameter between
the blocks when laid in the wall; this opening is filled
with cement mortar.

The blocks are made on a double machine, turning
out two blocks at one operation, and are 24 inches long,
8 inches high, and 4 inches thick.

Anchor Silo Blocks. This block makes a double
wall, with a continuous air space. It is controlled by
the Anchor Concrete Stone Company, Rock Rapids,
Iowa. Each block is made in two separate sections,

Concrete Silos

153

bound together with four ^-inch galvanized iron
rods, 8 inches long and turned 1 inch at each
end. The Standard
Anchor machine
makes a block 8x8x
24 inches, while the
Junior Anchor ma-
chine makes a block
8x8x16 inches. Each
machine makes
blocks to fit any de-
sired radius of silo.
This is accomplished
by having the mold
box equipped with
inside steel plates
which can be ad-
justed by set screws
to the desired curve.
The interior section
of the block is cast
with a groove in the
top in which rein-
forcing can be

placed. Anchor Blocks Laid Up in Wail

Keystone Cement Slab Silo. This system is con-
trolled by the Minnesota Keystone Silo Company, Min-
neapolis, Minn. The blocks or slabs used in a Key-
stone silo have a special design, the ends being wider
by 3 inches than the center of the slab. This, in addi-
tion to the tongue-and-groove edges, makes of each
block a key which securely locks the adjoining slabs.
The slabs or blocks are 24 inches long, 3 inches thick,

154

Concrete Silos

16 inches wide at the center and 13 inches at the mid-
dle. Each block is reinforced with two %-inch steel
rods, each end of each rod projecting into a small
cavity. When the blocks are laid up these ends are
connected and brought to tension by a special tool.
The cavity is then filled with concrete.

Millers' Sectional Interlocking Block Silo. This
system is controlled by the Goshen Concrete Tile
Manufacturing Company, Goshen, Indiana. The blocks
in this system are solid
blocks made of slush
concrete interlocking
at all edges. A double
rod of 5-16-inch iron
through each- bloc.k
makes the reinforcing
and forms an eye at
the end of each block.
The blocks are fas-
tened together by
means of a staple
passing through these
eyes, the open spaces around the eyes and staples
then being filled with mortar. The door frame used
in connection with these blocks is constructed of chan-
nel iron. On the side of the door jamb toward the block,
there are eyes every 12 inches to correspond with the
eyes on the block, so the door frame and blocks are
locked together by means of staples and spaces
filled with mortar, making joints same as between the
blocks themselves.

Perfect Cement Blocks. This is made on the per-
fect cement block machine, manufactured by J. J.
Coyne, Fond du Lac, "Wisconsin. This machine makes

Miller's

Interlocking

Block

Concrete Silos 155

a hollow block of two types, the two parts in the
block being connected either by a web of concrete
or by steel spacers. The blocks are made 8 inches
high, 9 inches thick and 24 inches long, with 21/2-inch
air space. The blocks interlock in both directions and
have a groove on top for reinforcement.

Perfect Reinforced Block. This system is the prod-
uct of the Perfect Reinforced Cement Silo and Cis-
tern Company, Delaware, Ohio. The Perfect Silo is
built with blocks 2 feet long, 1 foot high and 4 inches
thick.

Each block is reinforced with two iron rods run-
ning lengthwise of the block, 6 inches apart. Each
rod is looped or turned 6 inches from the end. These
loops in the rods coincide with the holes that are
formed edgewise through the block, 1 inch in diame-
ter and 6 inches from either end. In laying the blocks
these 1-inch openings are filled with cement grout and
the rod or dowel pin is pressed through the soft
cement, connecting the two blocks. Each pin is in-
serted in such a way that it passes entirely through
one block and half way through the block above and
the one below. By this arrangement of loops and
dowel pins, inserted in the holes through the blocks,
and the use of half blocks, joints are broken in the
same way as when an ordinary brick wall is laid. This
provides for a continuous lateral reinforcement around
the silo every 6 inches, and the dowel pins that run
through the blocks from the bottom to the top of the

156 Concrete Silos

silo form a vertical reinforcement every foot. A strip
of netting composed of 7 longitudinal and 12 vertical
steel wires, imbedded in the block just beneath the
outer surface, is designed to prevent any liability of
cracking of the face of the block. To unite the blocks
and to overcome the outward pressure or thrust, a
2-ply twisted steel cable of No. 8 wire is laid outside
the dowel pins between each course of blocks, in
grooves provided in the edge of the blocks for that
purpose, and imbedded in the mortar in which they
are laid. The ends of these cables are looped about
a continuous gas pipe, which extends from the top to
the bottom of the structure, through the blocks each
side of the doorway, in place of dowel pins. This same
gas pipe also passes through holes in the ends of the
ladder rounds.

Zagelmeyer System. This method of making silo
blocks is the invention of the Zagelmeyer Cast Stone
Block Company of Bay City, Mich., and is identical
with the system used by this company for making
building blocks, except that the silo blocks are made
to fit the curve of the silo instead of being straight.
The molds, which are of sheet steel, are assembled in
multiple form on roller bearing trucks, each truck car-
rying molds for thirty silo blocks. The truck is then
carried under the discharge end of the mixer and filled
with slush concrete.

Each block carries two air spaces, and has a depres-
sion in the top for carrying a continuous circle of rein-
forcing around the silo.

Molds are made in both rock face and plain. The
blocks can if desired be given a granite or other orna-
mental face, similar to the Zagelmeyer building blocks.

CHAPTER XVII

DOORWAYS, DOORS, ROOFS, ETC.

These topics have been dealt with in connection
with some of the systems treated, so that in this chapter
it is scarcely necessary to do more than take up some
general features of these parts of the silo.

Doorways. Doorways are of two types, known as
intermittent and continuous. These doorways are both
good, and it is a matter of individual preference as to
the one to select, although the separate openings are
preferred by a great many silo users. These openings
are usually 2 feet wide and 3 feet high, and are spaced
about 3 or 4 feet apart. This type of doorway makes a
stronger wall, but more difficulty is experienced in
removing the silage for feeding than with the con-
tinuous door.

An easily constructed intermittent door form for a
solid concrete wall silo is suggested by the Association
of Portland Cement Manufacturers as shown in the
illustration. Make a frame of 2x6 inch lumber as
shown. Then prepare a second frame of 2x2 pieces, and
nail it around the first. This will provide an offset or
jamb of 2 inches in the concrete, to receive the door
from the inside. This form should be made so that it
will fit closely between the inside and outside wall
forms.

The method of constructing a form for a continuous
door opening is similar to the one for separate open-
ings. Two pieces of lumber 2x6 inches are cut 5 feet
long. Two holes are then bored through each piece.

(157)

158

Concrete Silos

These holes are 2 feet apart and 2 inches from the edge.
The pieces are then ripped through the holes. A piece
of 2x2 inch lumber, beveled, is then nailed to the 4-inch
piece thus made. Cleats are nailed across the two pieces
which were cut. These cleats are to hold cross-strips
between the two uprights, for the purpose of keeping
the door forms the right distance apart.

2x2'

2x6'

Form for Intermittent Doorway.

When setting the form into the molds, the ladder or
door rods are placed in the holes of the door form. This
method of door-jamb construction has been in use for
eight or ten years, and has been found satisfactory.
The method of reinforcing across both types of door
openings is also shown herewith.

Doors. The doors for the continuous doorway may
be made of 2-inch planking, preferably tongue-and-
grooved. The doors should be 34 inches in width and
30 inches in height. Five pieces of planking 6 inches
wide, or 4 pieces 8 inches wide may be used con-
veniently. A %-inch hole is drilled on the vertical

Concrete Silos

159

center line of each plank to accommodate the bolt and
hook by which the door is held to the horizontal rein-
forcing across the door opening. The bolts used have a
screw eye on the outer side to which hangs a hook made
of heavy steel wire.

Non-continuous doors are perhaps easier to build
than continuous doorways, and if the owners are satis-
fied that they provide sufficient room for getting the

Method of Fastening Reinforcing When Silo Is Built With
Continuous Door Opening.

silage out conveniently, there is no objection to their
use, although on the other hand, they possess no great
advantage over doors of the continuous type. The
arguments often heard that the non-continuous door
silo is a stronger type than the other, and vice versa,

160

Concrete Silos

carry little weight, as either type may 'be made suffi-
ciently strong.

Non-continuous doors are often put in with a dis-
tance of about 2% feet between them, but the spacing
may vary to suit the individual owner. In all cases
the arches between the doors must contain an amount

Method of Reinforcing Around Intermittent Door Openings.

of reinforcing equivalent to the full amount of hori-
zontal reinforcing put around the silo. Thus, if the
doors are 3 feet in height, with a distance of 2% feet
between them, the horizontal reinforcing in the space

Concrete Silos 161

between the doors should be equivalent in amount to
that placed in 5l/2 feet of the wall where there are no
doors.

The doors may best be made of two thicknesses of
Ix6-inch matched flooring with a layer of tar paper
between. The Ix6-inch boards are held together by
two Ix4-inch cleats across the top and bottom, and one
2x4-inch cleat across the center. The middle cleat is
made larger than the others in order to take care of the
strain caused by the large bolt in the center. A 2x4,
40 inches long, or a similar piece of material, is placed
on the bolt, making a large "button" by which the door
is held to the wall.

The Roof. Perhaps the greatest advantage of a
roof is the lessened liability of the silage freezing. Not
only is it impossible to prevent freezing in severe
weather unless the silo is provided with a roof, but
during snowy or rainy weather the silage is mixed
with snow or wet down with rain. Furthermore, a silo
without a roof becomes a catching place for husks, dust
or anything carried in the wind and a favorite feeding
ground for the neighborhood pigeons and birds.
Although many silos are not provided with roofs and
the live stock eagerly eat the silage from them, it is
evident that a roof would not only reduce the amount
of frozen silage, actually save silage and preserve its
quality, but be worth its cost in making a more pleasant
place to feed from in bad weather. The roof is also
valuable in protecting and strengthening the silo and in
adding to its appearance.

A door for filling, large enough to admit the carrier
or elevator from the ensilage cutter, should be placed in
the roof. A simple trap door may be used for this pur-

162 Concrete Silos

pose, but a dormer window with glass is preferable.
Some light should be admitted to the silo for if not it
will be necessary to use a lantern when removing the
silage.

The pitch of the silo roof may vary from one-
quarter to one-half. The steeper roof permits the silo
to be filled above the top of the wall so as to be nearly
full after settling. A flat roof does not permit the
silage to be elevated to a point high enough to do this,
does not give the workman room for work during
filling, and does not shed the snow like a steeper roof.

.While roofs of various types are used with concrete
silos, it is most desirable that the roof be of concrete,
thus making this part of the silo as durable as »ny
other.

In some systems, special roof forms are provided ;
but where there are not obtainable a concrete roof can
be laid 4 inches thick over a temporary wooden form,
which will be left in place two or three weeks. The
concrete should lbe reinforced with steel rods %-inch in
diameter. Some of the rods are laid like the spokes of
a wheel, 1-inch from the under side of the roof. At the
eaves the rods are 18 inches apart ; but every other rod
runs only half-way to the peak, where it is tied to a
horizontal ring extending entirely around the roof.
There are four of these horizontal rings equally spaced
from the eaves to the center of the roof. Where the
straight or radial rods meet at the peak they should be
hooked and securely tied together. In the eaves an
additional ring is placed, around which are hooked the
outer ends of the straight rods.

Eaves on a concrete roof are not absolutely neces-
sary, but add much to the appearance of the silo.

Concrete Silos

163

Iron Roof. An iron roof for silos is made by the
C. ('. Fonts Company, Middletown, Ohio. This roof is
made in sections readily bolted together. It is of pure
iron, 20 to 24 gauge, and is
equipped with a large trap
door for filling. This door fits
over a raised rim in the roof,
making it weatherproof. These
roofs are made with a ventila-
tor and a heavy wired glass at
the top, admitting sufficient
light to light up the interior
of the silo. One advantage
of this kind of a roof is that
sections of it can be left off
while the silo is being filled.
This will allow of the silo
being filled to its full capac-
ity, while the settling of the
silage will be sufficient to give
working room when it is de-
sired to begin feeding from
the silo.

Winner Extension Silo
Roof. The special feature of M
this roof, which is made by 3
the Silo Specialty Manu- £
facturing Company at Clinton, \\ n >i •;..
Iowa, is that it allows the user to utilize the entire
space of the silo. That is, the roof opens outward from
the peak, so that the silo can be filled above the height
of the walls. As the silage settles the roof is closed,
giving the contents of the silo complete protection
against the elements.

164 Concrete Silos

The method of operation of this roof is well shown
in the illustration. It has a metal roof consisting of
separate segments which are hinged at the bottom and
can be opened until they stand vertical. When they are
opened for filling the silo the spaces between the seg-
ments are protected by wire mesh.

Buckeye Silo Roof. This is a sheet metal roof, made
in gambrel design with dormer window. It is made by
the Thomas & Armstrong Company, London, Ohio. The
same company also makes all-steel silo doors, and other
silo equipment.

Air-Tight All, Steel Door Frame. This is a continu-
ous door manufactured by the Silo Specialty Manufac-
turing Company at Clinton, Iowa. This is an inflexible,
unbreakable, steel door frame, requiring no packing to
make a tight door.

CHAPTER XVIII
How TO INCREASE THE SILO BUSINESS.

A firm of contractors and supply dealers in Sioux
City, Iowa, have adopted a novel method of promot-
ing the silo end of the business by erecting a sample
silo on their grounds 'and utilizing the lower part of
it for office purposes. This company is fortunately
situated at the stock yards, within 75 feet of the Live
Stock National Bank, so that the silo is just where it
will catch the attention of the men it is desired to
reach. It carries a conspicuous sign, calling attention
to the fact that the structure is for inspection and
that the office is inside. Leaflets are also sent out
among the farmers in the territory telling them of this
exhibition silo and showing illustrations of it and
also of silos which the company has constructed on
farms in the vicinity.

The sample silo has at least two advantages as an
advertising asset. There is no doubt but many farm-
ers will be attracted by it and will step in "just to
look around" out of curiosity. If the sales work is
what it should be, a fair proportion of these will ulti-
mately buy. The prospective customer is thus brought
right to the office instead of making it necessary to
go out after him, and any salesman knows what this
means, both in the saving of time and the advantage
of having the man on your own ground and with a
confessed interest in what you have to sell.

There will be still other men who know that they
want a silo and would come to the office whether there

(165)

166

Concrete Silos

were -a sample on exhibition
or not. The advantage of-
fered by the sample silo in
dealing with these men is
that the deal can be closed
up much more promptly,
avoiding the necessity of
spending time and expense
money to take the prospect
'out to see some of the silos
on surrounding farms.

By getting a man right in
the office the system of con-
struction can also be demon-
strated, arousing the interest
of the farmer in the simplic-
ity of the equipment, the de-
vice by which the walls are
kept true to line, etc. A
small section of the well can
also be cut away, if desired,
exposing the reinforcement
and revealing the stability
of construction and the hard
and enduring nature of the
material.

Silo Inspection Trip Conducted by a Cement Company.

Concrete Silos 167

While a sample silo of this kind costs a little money,
where a favorable location can be secured it would
seem to be a very valuable advertising asset ; and espe-
cially would this be true in thinly populated districts,
where a contractor, located in a central market town,
can bring to his office men whom he would otherwise
have to go many miles to reach.

Sample silos of a permanent nature are located on
the grounds of many of the state fairs, while tempo-
rary sample sections are frequently put on display at
various expositions. These are usually put up by the
promoters of the various systems of construction, and
they serve the double purpose of stimulating a demand
for silos and of reaching contractors and interesting
them in this class of construction.

Some of the more progressive manufacturers have
well devised campaigns which are put into effect for
the benefit of contractors who buy their outfits. In
addition to furnishing him with suitable printed mat-
ter, albums of photographs, etc., each contractor is
requested to send in to the company the names of farm-
ers in his locality who should own silos — not a miscel-
laneous list of names, but a list which is carefully se-
lected and not too large to have devoted to it some
personal work on the part of the contractor himself.
To these people the manufacturer sends out a letter
setting forth the advantages of concrete silos in a brief
way and calling attention to the fact that the local
contractor is now prepared to build such a silo for
them. These letters are followed up at suitable inter-
vals by letters sent out by the contractor, but the copy
for which is supplied by the manufacturer ; and in the
mean time it is expected that the contractor is doing
more or less personal work with these people, at least

168

Concrete Silos

to the extent of taking advantage of casual meetings
when they are in town if he does not get out to see
them at their own homes.
Photographs are won-
derfully helpful. In addi-
tion to the albums sent out
with an outfit, some man-
ufacturers stimulate busi-
ness for their customers by
sending out additional
photographs from time to
time. These may be of
new silos just completed,
especially if there is any
unusual feature about the
silo or if it is for some
person of prominence; or
they may show how a con-

Sample Silo and Office at Sioux City, Iowa.

Concrete Silos

169

crete silo has successfully withstood a recent fire, tor-
nado or earthquake.

The contractor can also assist in this part of the
work by having photographs made of the silos which
he erects and using
them in his own local *
work as well as sup-
plying them to the
manufacturer for the
betterment of the in-
dustry as a whole.

Some silo builders
have secured permis- '
sion from their cus-
tomers to place at the
entrance to the farm
a neat sign bearing
an inscription some- ><
thing like this:

The Concrete Silo
On This Farm Was

Built by the

Company. Drive in
and Examine It.

In most localities
the principal opposi-
tion to be combated
is from the wood silo.
For the representa-
tive of this type is Silo on Illinois State Pair Grounds.

more frequent and more persistent than any other, and
he is in fact the only silo salesman whom many a

170 Concrete Silos

farmer sees. This is because the wood silo is a factory
product, capable of being shipped out " ready made"
under the supposition that the farmer can put it up
himself, thus lending itself readily to the building up
of a large sales organization. These agents who are
sent out over the country know that their main business
is to get orders, and an important part of their equip-
ment for so doing is a handful of misinformation about
concrete as a silo building material.

But with no knowledge to the contrary, a farmer
is perhaps not to be blamed if he believes the man
who assures him positively that the acids in silage will
eat out a concrete silo in two or three years. It is
necessary that this propaganda be combated, and the
authoritative statements which have been given out by
so many of the agricultural schools of the country
should be given wide publicity, as they will go a long
way toward forming in the mind of the user of silos a
saner and more correct view of the situation. State-
ments of this nature can well be included in some of the
printed matter sent out by contractors to develop the
silo business ; and editors of newspapers should be pre-
vailed upon to print matter pertaining to silos from
time to time.

It is generally conceded that advertising in local
newspapers on the part of contractors will form a valu-
able adjunct to other forms of development work. If
this advertising can be given a local turn at times, such
as printing illustrations of silos which have been built
in the neighborhood, or letters of recommendation from
local men who are pleased with their silos, this adver-
tising will have a double value.

A farmer can often be interested in concrete silos
by having pointed out to him the fact that most of

Concrete Silos

171

the materials can very likely be found right on his
own farm and that he will be the gainer to that ex-
tent. One Iowa contractor has taken a somewhat novel
way to emphasize this point. He says in his adver-
tising:

// you have sand and gravel on your own
farm or nearby, we will buy it from you.
This representation to the farmer that he is going
to get some of his money back immediately will prob-

Exhibition Silo at Texas State Fair.

172 Concrete Silos

ably be more convincing than would a mere statement
of the saving effected by the use of materials from his
farm.

A considerable amount of promotion work on all
kinds of silos can be carried on during the winter,
when the farmer is not so busy and is looking ahead
to the improvement of his farm.

The farmer as a class usually looks farther ahead
than any other man. Of course, there are farmers
who live from hand to mouth, as the saying is, just the
same as can be found in any other calling ; but for the
most part you will find among well-to-do farmers more
accurately detailed plans for the future than among
almost any other men that one might name. The very
nature of their occupation leads them to plan that way.
Practically nothing that a farmer does comes to frui-
tion until a considerable time after it is started. In
this sense he is 'always working for the future. His
grain is planted in the spring and harvested in the
fall; the kind of stock that he will raise is made the
subject of serious study sometimes years ahead; the
products of his farm must be stored away at certain
seasons for future use ; and his bank account, which is
swelled at periods of the year when products are being
sold, must be conserved to provide for the times when
there will be no income.

It is perhaps for some of these reasons that con-
crete products manufacturers have found the farmer
market a most satisfactory and profitable one. It
might be mentioned also that the farmer is a good ad-
vertiser. He delights to make every business transac-
tion the subject of conversation. Where the city busi-
ness man will buy a thing in a hurry and promptly

.

Concrete Silos 173

forget about it, the farmer will buy slowly and only
after much discussion, and once having bought he
will talk about his purchase for some time afterward.
Sell him what he believes to be a good product 'and the
chances are that you will soon get other orders from
the same neighborhood; but if he believes that you
have not treated him right, it will be very difficult to
sell to any of his neighbors for some time to come.

In some localities the manufacturers of concrete
silo blocks and staves have discovered that they can
keep business going at a fairly brisk pace throughout
the winter by showing the farmers the advantage of
hauling these things in the winter time. In fact, it
seems to have been the farmers themselves who first
discovered the advantages of such a system; but the
products men have not been slow to take advantage
of it in a number of instances.

In one Wisconsin town a block manufacturer was
asked a quotation on a certain bill of silo blocks, in the
middle of winter.

"They will cost you 16 cents apiece/* said the
manufacturer.

"All right, I am satisfied/' said the farmer; "I'll
take the first load of them out with me today/'

The block man was alive to the advantage of quick
sales, but he, at the same time, did not want to rush
his product out without sufficient time to cure, so he
said:

"Those -blocks are only eight days old. You had
better leave them here for a couple of weeks longer
and let them cure. If you take them now it is pretty
sure there will be a number of them broken when you
get them home."

174 Concrete Silos

" There is no time like the present," was the reply
of the farmer, or words to that effect. "Today the
weather is fine, the roads are smooth and well packed
down, and I -can carry just as many blocks as I can
pile onto my sled. In two weeks there may be a thaw,
or snowdrifts, or a spell of stinging cold, or a run of
sickness in the family. I would rather take them now
and stand the breakage myself. After I get them home
they can cure just as well in my yard as yours. "

And so the blocks were taken out immediately.
Not many blocks were broken, but such as they were
the loss was willingly borne by the farmer, for he had
done the hauling in time which would otherwise have
been almost a total loss, over good snow roads, doing
the hauling with a sled, which is much easier to load
and easier to haul than a wagon, and the blocks were
on hand ready to begin work as soon as the first robin
appeared.

From the standpoint of the block manufacturer,
too, the transaction was a most satisfactory one. It
helped him to keep his plant running during the cold
season without unduly crowding the yard; it helped
to distribute his yard labor over a longer period, and
as the farmer had the money in the bank from the
sale of his fall crops, and was glad to take advantage
of a small discount, it helped the manufacturer to keep
up the financial end of his business.

THE PERFECTION CONCRETE STAVE SILO

PERFECTION CONCRETE STAVE SILO COMPANY

516 CLAPP BUILDING. DES MO1NES. IOWA.

There is only one way to
manufacture concrete, and
that is by the "Wet-Mix"
process. Our Perfection Con-
crete Stave Silo Stave is made
by the "Wet-Mix" process;
the staves are cast in moulds
with an aggregate of one
of cement, two of sand, and
three of gravel or crushed
rock, and when cured, pro-
duce a strong, non-porous
product and present a hand-
some appearance.

Our "all steel" large door
system appeals to the farmer
and silo users. We sell our
moulds outright; we make no
charge for royalties; there is
no "blue sky" or exclusive ter-
ritory connected with our
proposition. You pay for
what you get. In another
part of this book is a com-
plete description of our silo.
CONCRETE WORKERS

Get into the silo business.
It furnishes splendid profits;
it is a growing business. The
silos you erect this year will
be for many, many years to
come "silent salesmen" for
you. When you go into the
concrete stave silo business,
get the best. Get a system
that permits making the staves
by the "wet process"; that
permits mortar to be placed
between the joints of every
stave; that will give you a
malleable door frame with an
all steel door and steel ladder
combination; a silo without a
word of criticism and easy to
erect, and with splendid profits
to the contractor. Write us
for information, and we will
gladly send you our literature.
Excellent terms of payment to
responsible people.

The Polk System

OF

Concrete Silo Construction

(MONOLITHIC)

PATENTED OCTOBER 23. 1906
PATENTED DECEMBER 29. 1908

Polk Genung Polk Co., Inc., Fort Branch, Ind.

INVENTORS AND MANUFACTURERS

Opportunity Eventually concrete will displace all other
* material used in silo, water tank, and
grain storage construction. Agricultural schools and
experiment stations, bankers and insurance companies are
backing concrete silo building. They are backing the
POLK SYSTEM because it renders a distinct service in
silo construction. Farmers have become prejudiced in
favor of concrete silos because of their ultimate cheapness
and of the lasting service they render. In the field of silo
construction lies the greatest opportunity of the American
contractor today.

The contractor who is equipped with a POLK SYSTEM
machine and POLK SYSTEM methods can fully guarantee
any building he erects. He has the assurance of a big,
successful experience behind him. He knows that his
work will please far beyond expectation.

Facilities The new PPLK SYSTEM factory with its

modern equipment enables us easily and eco-
nomically to manufacture machines with every single
excellence that years of experience have proved desirable.
Not a single expense has been spared that will help to
lower the cost of producing POLK SYSTEM machines and
equipment and still maintain the high POLK SYSTEM
standard of quality. We are putting on the market today
the most thoroughly designed 'and the most durable
machine that can be made for the erection of monolithic
concrete silos.

Polk System Silos Are Not Built of Pieces

THE POLK SYSTEM MACHINE

and They Cannot Go To Pieces

THE POLK SYSTEM MACHINE

Description The POLK SYSTEM is in reality a com-
pletely detailed plan for all kinds of cir-
cular monolithic concrete construction. It specifies mix-
tures and proportions, it keeps the contractor abreast with
the times, it reduces construction costs and insures a
definite progress each day, and it makes provision for the
safety of laborers. More than all of these, it insures to
the farmer a flawless structure which will keep his silage
secure against every known foe of good silage. The
POLK SYSTEM is much more than a mere machine.

Machine The POLK SYSTEM machine is an all steel
equipment for the erection of circular mono-
lithic concrete structures. It has been developed with two
things in mind — ease of operation and the production of
absolutely flawless structures. The POLK SYSTEM,
machine automatically keeps the walls plumb, does away
with an elaborate, complicated, risky system of scaffold-
ing, imposes no strain upon the section of wall already
built, and so unifies and simplifies construction that any
intelligent workman can easily erect the most perfect,
monolithic structure on earth.

The unifying, simplifying, protected principle of the
POLK SYSTEM machine is the use of a centermast. This
centermast is erected at the center of the floor of the
structure and is carefully plumbed by means of guy wires
attached to the top. It is a 4-inch steel pipe provided
with a series of transverse holes to receive a heavy steel
pin. This pin supports a widely flanged collar which
serves to support the jack by which the forms are lifted.

Resting upon the jack is a hub, consisting of a flanged
base collar and a top dished collar connected by a central
pipe of sufficient diameter to work easily over the center-
mast. From the base collar of this hub radiate steel Tees
which are supported from the upper collar by adjustable
hanger rods with chain clevises.

The wall-forming forms are made in two widths — four
and five feet. Each form consists of eight separable sec-
tions, each of which is reenforced and stiffened by a steel
angle frame around the edges. The inner and outer steel

Polk System Machines Render the Service

THE POLK SYSTEM MACHINE

wall forms HIV care-
fully rolled and
tested for exact cur-
vature. They are
rigidly bolted to the
radiating steel Tees.
The outer sections
are bolted together
at their ends thru
holes in the frames.
The inner sections
are similarly fas-
tened together, but
they carry a steel
wedge between them,
the lifting of which
allows them to swing
free. The fact that
both inner and outer
forms are securely
bolted to the rigid
steel Tees insures
perfect curvature
and alignment for
every portion of the
wall'.

For placing the
concrete in between
the forms a V-shaped
dumping bucket is
used. This bucket is
supported by a crane
pivotally attached to
the centermast di-
rectly above the top
collar of the hub. It
can be easily swung
to any part of the
wall space. It is

Polk System Silos Are Indestructible

THE POLK SYSTEM MACHINE

hoisted by means of a rope and series of pulleys so arranged
that the hoisting force is applied horizontally from with-
out the structure. A small opening thru which the hoist-
ing rope works is cut in the wall near the bottom of the
first fill of concrete. When the bucket has been hoisted
it is coupled to the carrier on the crane by means of a
hinged hook. Then it is swung to any part of the wall
space desired.

The scaffolding, both inner and outer, is swung from
the steel Tees which project some distance beyond the
wall.

fl . . The operation of the machine is very simple.
UperatlOn

forms are set, the reenforcing bars are
placed in position, the concrete is mixed, hoisted, dumped
and packed between the forms, and allowed to set.

On the next morning the nuts connecting the sections of
the outer forms are loosened, the steel wedges fixing the
sections of the inner forms are lifted, and both inner and
outer forms swing free from the wall. Then by means of
the jacks resting on the widely flanged base collar, the
whole mechanism is lifted until in position for a new
fill and the forms again are set by means of the bolts and
the wedges.

The actual raising of the forms for a new fill does not
require more than ten minutes. Though some POLK
SYSTEM contractors have successfully placed two fills a
day during hot, dry weather, one fill >a day is the most
satisfactory rate of progress.

Arlvnnf arr The POLK SYSTEM machine automatically
Advantage* keeps the wall of regular thickness, true to
a circle and perfectly plumb. It does away with an
always risky system of scaffolding and allows no strain
on the "green wall." It is especially adapted for high
work. It also provides a rapid and economical means of
hoisting and depositing concrete in the form. Besides all
of this the contractor can, with the standard POLK
SYSTEM machine, build any sort of circular reenforced
concrete work, such as grain storage bins, coal pockets,
smoke stacks and water tanks, besides the silos that the
farmers are calling for. _

Everybody Believes in the Polk System

THE POLK SYSTEM MACHINE

T . . i Knoxville, Tenn., Jan. 16th, 1915.

testimonial p0ik-Genung-Polk Co., Ft. Branch, Indiana.

Gentlemen: — In answer to your letter of the llth inst.
I am very willing indeed to advise you concerning my
experience with the POLK SYSTEM.

The three Polk System machines bought June 1, 1914,
ran steadily the remainder of the season and netted me a
splendid profit. I attribute no little of my success to tha
certainty with which your machines do their work. Actual
construction costs, after applying your schedule to local
conditions, ran close with my schedule — so I know just
"where I was" all the time. The depreciation on my
equipment was negligible. My one best job was a con-
crete water tower 124 ft. high which I built with one of
my Polk System machines.

This year inquiries for silos are coming so fast I am
quite sure the demand will be greater than I can supply
with three machines and will have to buy more machines.
I can plainly see that this permanent silo business offers
big opportunity for contractors and I am glad I adopted
the ' ' line. ' ' Yours truly,

J. A. HIGGS.

iiiT . The POLK SYSTEM machine is made of the

Warranty best material obtainable and by the most
skillful mechanics in the business. Every single part of
the machine is tested before leaving the factory. The
POLK SYSTEM machine is warranted to stand up to the
hardest handling without breakage of any kind. The
entire resources of the POLK SYSTEM and the whole
POLK SYSTEM reputation stand back of every single
POLK SYSTEM machine.

If there are points about the POLK SYSTEM that are
not clear in your mind, kindly allow us to clarify them.
If you want more complete information, if you want to
know what our contractors are accomplishing, told in the
words of the contractors themselves, we shall gladly fur-
nish such information and such testimonials at your
request. Prices will be furnished for delivery to any rail-
way point in the United States, Canada or Mexico, or to
any port for export trade.

Polk Genung Polk Co., Inc., Fort Branch, Indiana

The Hurst Silo

Patented 1902, 1904, 1914

THE CHAS. B. HURST COMPANY

Established 1904

819-829 Exchange Ave., Union Stock Yards

CHICAGO, ILL.
Chillicothe, O. Live Stock Exchange Bldg., Kansas City, Mo

Prrkdurf We are *^e owners of tne Hurst Eeinforced Concrete
irUUULl Block Silo Patents and sole distributors of Hurst
Patent Gravity Mass Block Molds for casting these Hurst Silo
Blocks.

Op«rrinfrinn

Silos are built of reinforced concrete blocks
made in Hurst Patent Molds using the poured
The Silo system. The Blocks are 23% inches long, 11%
inches high and 4 inches thick; are dense, water-
proof and have tremendous crushing resistance. Each block has
running through it two steel rods % inches thick. These rods
have their ends out turned at right angles in recesses in the ends

of the block, as' shown in Figure 3,
No. 10. They are curved to form a
perfect circle in any desired circum-
ference.

The blocks are laid in cement
mortar same as any building block.
The only difference is in the rein-
forcing and locking device. Each
circle of blocks when laid in the
wall forms a circular chain of which
each block with its reinforcement is
the long link. When blocks are set
steel links are placed over the ends
of the reinforcing bars, tension ap-
plied and then filled with cement.
(See Figure 3, No. 10, and Figure 2.)

In the above manner Hurst Silos
are erected. For closer detail see
Figure 3. When walls are complete,
a plaster i/4-inch thick of one part
cement, two parts sand, one-fifth
hydrated lime is applied, making a
smooth, waterproof interior, which
insures perfect settling and keeping
of ensilage.

HURST SILOS ARE SOLD EVERYWHERE UNDER A WRITTEN GUARANTEE

THE HURST SILO

Hurst Silo Molds Hurst Patented Gravity Mass Block Molds
are furnished in sets of ten molds each,

having a capacity of two hundred blocks per day. They are made
of light steel of great strength and are practically indestructible.
Each mold consists of two sides, two sets of division plates, clamps
for locking molds, and core covers. The sides of the mold are of
pressed steel, fitted with hollow pressed steel cores, which hold the
reinforcing rods in position when the blocks are poured.

Each mold
makes 10
blocks at one
filling — full
size or half
blocks which
are used at
the doors.

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3. awry emrs s REJNfD/fCEMwr

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0. SLOT CWER.
£ CUWED STttL /wmTXK
f ADJUSTABLE CLAMfS.

Simple, Durable, Practical and
Economical

The manufac-
ture and sale
of the Hurst
Silo is a com-
mercial proposition, and
will enable you to work

twelve months in the year, therefore, our proposition should
interest you.

A small investment in equipment will take care of an immense
amount of business, and insure quick returns.

For more than eleven years Farmers and Stockmen have recog-
nized the Hurst Silo as a safe investment and an ornament to the
farm.

Eleven years and not a failure— That 's the Record. The Hurst
System of reinforced concrete construction reduces to the minimum
time, labor, expense and competition.

We have some more openings for live, responsible parties, but
they are going fast. Don't put it off, but act now. Write for
particulars and catalog.

You Can Make Hur.t Silo Block, in the Dead of Winter

THE HURST SILO

Operation

1 — Bolt every
4 feet for
fastening
roof.

2— Step lad-
der.

3 — Bolt every
3 feet for
fastening
chute.

4 — Door, door
frame, door
ladder
steps.

5— How lad-
der steps
lay in mor-
tar joints.

6 — Eeinf ore-
ing rods.

7 — Sectional
interior
view show-
ing rein-
forcing
rods and
links in
blocks, also
the smooth
plaster fin-
ish wall on
the inter-
ior.

8 — Concr et e
floor. Hurst
Silos can
be built
with or
without
this con-
crete bot-
tom.

9 — F o u n d a -
t i o n ex-
tending be-
low frost
line.

10 — Shows reinforcing rods ready for steel link,
link in position, tension applied to rods and
finally reinforcing rods covered to prevent
corrosion.

Make Your Blocks in Your Plant, Er.ct Them on the Job

THE HURST SILO

These Prominent Men and Institutions
Use and Endorse Hurst Tanks and Silos

L. F. SWIFT

President, Swift & Co.
O. W. LEHMAN

The Fair Store, Chicago
THE ELMENDORF FARM

Lexington, Ky.
W. E. PINNEY

Banker, Valparaiso, Ind.
ILLINOIS STATE FAIR ASSOCIATION

Springfield, HI.
M. W. SAVAGE

Owner of the Famous Dan Patch
XORTH OAKS STOCK FARM

Jas. J. Hill, Proprietor
P. W. CLIFORD

Railroad Contractor, Valparaiso, Ind.
CHARLES KELLY

Pres. National Live Stock Commission Co.
S. P. STEVENS

Sales Manager, Reid, Murdoch & Co.
JAMES BROWN

Head Buyer, Armour & Co.
M. WOLFE '

Broker, Union Stock Yards, Chicago
W. H. LEAZENBY

Banker, Bethany, Mo.
L. B. COCKRELL

Banker, Winchester, Ky.
THOMAS JOHNSON

Pres. Lorain Coal & Dock Co., Columbus, O.
NORTHERN INDIANA LAND CO.

Demotte, Ind.
CAVE VALLEY LAND AND CATTLE CO.

Peoria, HI.
THE POLK SANITARY MILK CO.

Indianapolis, Ind.
CALDWELL & SON

Burlington Jet., Mo.

B. C. RHOME

Pres. of North State Bank, Ft. Worth, Tex.
E. E. BETTS

Supt. Transportation, C. & N. W. R. R.
G. A. STEPHENS

Pres. Moline Plow Co.

C. D. THOMPSON

Trenton, Mo.

It Will Cost You Nothing To Investigate.

Thirty Silos Were Built for One Man. All Were Hurst'*

Reichert Circular Adjustable
Metal Molds

Reichert Mfg. Co., Inc.

1436-1440 Booth Street

Milwaukee, Wis.

PRODUCT:

Reichert's circular adjustable equipment, consisting of
metal molds and accessories for all kinds of circular mono-
lithic concrete construction; Reichert Metal Molds (Pat-
ented) for any type or size of concrete construction.

SCOPE OF USE FOR CIRCULAR ADJUSTABLE
EQUIPMENT.

Reichert's Metal Molds
are adapted for use in Gen-
eral Concrete Construction
of Silos, Elevators, Cis-
terns, Railway and Water-
tanks, Barns, Milk-houses,
Coal-pockets, etc., etc.
ADVANTAGES:

Reichert's Molds are suc-
cessfully operated with
common labor; can be used
either with or without a
round or square chute;
adjustable to any diame-
ter or wall thickness; use
less room in transportation
or storage; any height of
wall. Instead of having an
angle iron on the horizontal
edges a band iron is riveted
to the horizontal edges,
which allows the molds to
take the required arch of
various circles. The bands
are set back on one mold
and project on the other,
thus making a lap joint.
This lap joint making a
smooth wall and off-sets or
' ridges cannot be made.

Reichert's standard molds have been successfully operated
on structures varying from 6 ft. 0 in. to 40 ft. 0 in. in
diameter; from 2 ft. to 85 ft. in height, and wall thickness,
varying from 3 in. to 1 8 in.

The same unit mold since 1905. This record means —
the endurance of an idea, the permanent satisfaction of a
definite design.

OPPORTUNITY:

Stop and consider what one Reichert Adjustable Equip-
ment can do. Some farmers need big silos, others want them
made smaller. With a Reichert outfit you can satisfy them
all with no extra outlay. One equipment does it all.

TESTIMONIAL:

Ballinger, Texas, May 19, 1915.

* * * I am having great success with my forms,
building six feet easily on a twenty-foot silo, each day.

Silo building is taking a boom in the county and I have
all I can possibly do.

Respectfully,

Chas. Eisenhuth.

ROOF MOLD:

The dome roof is the most unique design of any style of
roof ever placed on a concrete silo. The Reichert Roof
Mold consists of curved segrnents which rest on the silo
wall and are locked to a hub, or ring, at the top. The
angles of the separate sections fit into this hub, or ring,
thus locking the entire equipment together. The segments
of the roof can be packed closely together and loaded in a
small space in moving from one job to another. The roof
molds include the complete cornice mold and a mold for a
dormer window.

REMARKS:

We are willing to go further than merely sending you

our litera-
ture, prices,
etc. We will
gladly show
you the op-
eration o f
these molds
right on the
job or in
our factory.
Once seen,
you'll have
none others
but the
Reichert.

CHAS. H. SWAN

"Superior Lock" Stave Silo

The latest and most up-to-date stave silo on the market

The Chas. H. Swan Circular Staves

The Chas. H. Swan ''Superior Lock" Staves are 30 inches

long, 10% inches wide, 2y2
inches thick, and are circular
to conform to the circle of the
silo, having a continuous
tongue and groove around the
stave completely locking with
6 other staves. With the
tongue and groove or shoulder
joint each stave has a true
bearing with each other, and
make a perfectly smooth silo
inside and out, and with the
staves made on a circle it
makes the silo perfectly round
and one of the easiest to erect.
A heavy galvanized band or
hoop encircles each tier of
staves. In erecting the Chas.
H. Swan "Superior Lock"
Stave Silo no expert help is
necessary as the staves set up
as easily as setting up toy
blocks.

Chas H. Swan

Labor Saving Stave Machine

The machine for making the
Chas. H. Swan, "Superior
Lock" Staves is the last word
in mould construction. All
parts of the mould are perfectly
milled with special milling
cutters, the rear section of the
mould is securely fastened to
the base, the front section is
hinged to the base and swings
down, the ends are hinged to
the rear section and swing out
and when closed are locked to
the front section with heavy

malleable clasps, the mould can be easily adjusted to make
different curved staves. This machine was designed by Chas.
II. Swan with a view of giving the contractor a labor saving
machine, one that is simple in construction, with few oper-
ations, and one that can be used with an automatic tamper.
One of these machines is capable of constructing 600 perfect
staves daily.

contractor who wishes to engage
in the best paying propositions of the
day; one that will pay a larger percentage of profit on your
money than you can receive from any other source; a busi-
ness that is not here for a day, but one that is here to stay,
and getting better each year — then begin at once to manu-
facture and erect " Superior Lock" stave silos.
Write for complete information about this up-to-the-minute
stave silo, and get our big money making proposition. We
are sure it will please you. Write today.

Swan Concrete Stave Silo Co.

Cassopolis ... Michigan

Winner Opening Silo Roof

Mr. Concrete Man, are you
fully abreast of the times?
Have you felt the commercial
pulse, the wants and needs of
people in every requisite of
the silo you are now selling?
For instance, take the roof
you are selling and installing
on your silos. Is it such as
you can honestly and earn-
estly recommend to your pa-
trons? Whether it be wood,
iron or concrete, if it is a sta-
tionary roof it is badly out of
harmony with silo construc-
tion progress, — the wants and
needs of the farmer.

Listen! You sell your cus-
tomer a concrete silo, — splen-
did structure, yet, if you rec-
ommend and sell him a sta-
tionary roof, you are doing
him an injustice. You are
compelling him to use only
75% of his silo. Is It Right?

Progress — The last word in
the silo world— THE WINNER
EXTENSION ROOF — allows
the farmer to use every cubic
inch of his silo space. Adds
25% to the capacity of the
silo. The WINNER EXTEN-
SION ROOF gives light, fresh
air, ventilation, convenience
during filling time; gives per-
fect protection to silo and en-
silage; easily installed on silo,
and easily opened and closed.

You owe it to yourself — you
owe it to the men whose
money pays for the silos you
build, that you give them an
opportunity to use every foot
of silo you sell them. The
WINNER EXTENSION ROOF
does this, — you should recom-
mend and sell it. The farmer
needs and wants the EXTEN-
SION ROOF.

We make the WINNER EX-
TENSION ROOF just fit and
right for your particular silo.
To legitimate builders and
dealers we allow a neat profit.
Write us for our proposition.

SILO SPECIALTY MFG. CO.

423 West on Bldg. :-: Clinton, Iowa

Build for Permanency

The silo which defies time and
elements is the concrete silo.
Years may come and go but the
concrete silo will stand as a
symbol of 20th century perma-
nent construction ideas. Yet 99%
of the present concrete silos
have one great weakness, — THE
DOOR FRAME AND DOOR.
It is crude, ill-fitting, cumber-
some, and really inadequate for
its purpose.

Perhaps your silo door and
frame are not as they should be.
L,ook into the latest and most
scientific door frame constructed,
— the AIR-TITE all steel door
frame. With it you can ap..
proach your prospective cus-
tomer and say: "With my silo
you get the best and most prac-
tical door frame constructed."
Consider These Points: The silo
door is solely for the purpose of
discharging silage as needed.
That this may be done quickly
and with the least possible la-
bor, the door must be continu-
ous. The AIR-TITE is continu-
ous. You build your silo air
tight because the admittance of air to silage will spoil it. Then,
should not the door be as tight as the silo wall? The AIR-TITE
door is so.

You construct your silo to stand the test of time. Should not
your frame and doors be likewise? The AIR-TITE frame is all steel
— inflexible, unbreakable, defying time and elements like King Cons
crete. But more, — your customer, the farmer wants simplicity,
ease of operating, etc. All this he finds in the AIR-TITE. No felt,
no paper packing, no freezing of door to frame. Just a whole lot
of srood things about the AIR-TITE that you should know. Our
booklet. "Modern Silo Ideas," tells you about it. Write for it.

Silo Specialty Mfg. Co., c2™

423 Weston Bldg.
- IOWA

Monsco Equipment

For Building Concrete Silos, Grain Bins and Tanks

Monolithic Silo and Construction Company

351-3 Peoples Gas Building, Chicago, Illinois

PRODUCT — Builders of Molds and Equipment for the
construction of Monolithic Silos.

DESCRIPTION — Monsco Molds are built very heavily of
16 g-a. black steel sheets in all standard sizes. The molds
are made in two sections, each 3 feet high, and each circle
is divided

into segments ,

of convenient
size. The
molds are re-
inforced with
%" steel an-
gles and
channels
welded to the
sheets to in-
sure rigidity.

The chute
form is an
integral part
of one of the
segments and
is adjusted to
proper position by means of transverse turnbuckles.

With each equipment comes a scaffold-hoist and bucket.
The scaffold is raised at will by two cast-steel worm-geared
winches attached to the center mast. This equipment does
away with building false work of any kind.

OPERATION — The operation of Monsco Molds has been
so simplified to make it easy for even common labor. Each
mold is BO divided to make every segment convenient in size
and weight for easy handling and interchangable. Three
feet of wall is poured at a time. Six feet a day. Next day
the lower 3 foot section is released, raised and set ready for
pouring. This section clamps onto the lower three foot
section which is filled with concrete, set sufficiently to
eliminate the possibility of a wall fracture. The molds are

entirely independent of the center-mast. This does away
with constant plumbing of the center-mast every time the
molds are raised. The scaffold and hoist are also raised to
points of advantage on the steel center-mast.

OPPORTUNITY — In the Monsco system the farmer is
given a continuous door (one easily installed and removed)
a concrete chute — two items the up-to-date farmer positive-
ly demands.

With the Monsco
equipment cold-
drawn steel mesh
reinforcement is
used. This type of
reinforcement is in-
finitely superior to
bar or rod reinforce-
ment, as it makes
the wall reinforced
uniformly through-
out. On our own
work we use 38-Inch
width mesh, thus
giving an oppor-
tunity to lap 2
inches on each
course. This gives
you strong talking
points to farmers on
strength as well as
permanence.

OUR SPECIALTY— Why, ask the farmers, don't you build
a concrete roof on the silo? That's just the question we ask.
Owners of Monsco Molds are getting more for the silos
they build and also save the cost of buying a steel roof.
Their Monsco Roof Molds enable them to produce excellent
roofs. This mold can be erected in 90 minutes and dis-
mantled and removed in 60 minutes. Ask us about it when
talking molds.

REMARKS — Our copyrighted instruction sheets are mailed
to every customer as soon as the order is booked. These
instructions cover every possible detail, and we leave noth-
ing to guess work or experimenting on the part of the
operator. You can't go wrong with Monsco Molds. Write
for our latest literature. We have splendid catalogs on the
silo proposition as well as our equipment. Ask for it.

Monolithic Silo & Construction Company

351-3 Peoples Gas Bldg.,

Chicago, Illinois

Perfect Reinforced Silo Block

Perfect Reinforced Cement Silo & Cistern Co., Delaware, 0.

PERFECT SILO BLOCKS are shaped to the radius of the silo, and are 24
inches long, 12 inches high and 4 inches thick. The blocks lay up large, re-
ducing the cost of laying, while on account of the thin wall they are not too
heavy to handle.

Each block Is reinforced with two iron rods running lengthwise, 6 inches
apart. Each rod is looped 6 inches from the end. These loops in the rod
coincide with the holes that are formed edgewise through the block 1 Inch
in diameter and 6 inches from either end. In laying the blocks these 1-inch
openings are filled with cement grout and a rod or dowel pin is pressed
through the soft cement, connecting the two blocks. Each pin is inserted in
such a way that it passes entirely through one block and half way through
the block above and the one below.

This provides for a continuous lateral rein-
forcement around the silo every 6 inches, and
the dowel pins that run through the blocks
from the bottom to the top of the silo form a
vertical reinforcement every 12 inches.

A strip of netting composed of 7 longitud-
inal and 12 vertical steel wires, imbedded in
the block just beneath the outer surface, is
designed to prevent any liability of cracking
of the face of the block. This virtually forms
a steel covering in the block near the outer
surface of the entire silo.

To unite the blocks and to overcome the
outward pressure or thrust, a two-ply twisted
steel cable of No. 8 wire is laid outside of the
dowel pins in the mortar between the courses
of blocks, in grooves provided for that pur-
pose. The ends
of these cables
ire looped about
a continuous
gas pipe which
extends from
the top to the
bottom of the
structure,
through the
blocks each side
of the doorway.
This gas pipe
also passes
through holes
in the ends of
the ladder
rounds thus the
cable and the
ladder rungs in
connection with
the gas pipe
form acomplete
r e i nforcement
around the silo
from the top to
the bottom,
throughout each
foot of its
height, which
r e i nforcement
is four times
more than suf-
ficient to with-
stand the pres-
sure of the en-
silage, but it is
so made in or-
der to withstand
the heat of a
possible flre.

This illustration shows the con-
tinuous doorway with ladder rungs
across same every alternate course of
blocks, and the manner of connecting
the ladder rungs and the twisted steel
cable by means of the continuous gas
pipe passing through the dowel pin
holes in the blocks each side of dooi-
way. It also shows the rabbet formed
in the edge of the doorway blocks
to receive the doors. The dotted
lines at the right indicate positions of
gas pipe, dowel pins, cable, netting
and loop wires.

Perfect" Silos Are Never Adversely Criticizde

Playford Stave Silos

Playford Mfg. Co., Inc.

Elgin, Illinois

Those who live in the states of Minnesota, North and South
Dakota, Iowa, Nebraska and Wisconsin, and wish to acquire an
agency or manufacturing; and sales rights in same, address the
MINNESOTA CEMENT CONSTRUCTION CO., LONG PRAIRIE,
MINN.

PRODUCT — A reinforced, ribbed, slushed concrete stave silo of
great strength and matchless durability and efficiency.

DESCRIPTION
— The staves
are slush mold-
ed in special

molds. Each End yiew of Staves, Showing Off-set Hoops and Form of
stave is thor- Construction and Recess for Pointing Outside,
oughly reinforced with bars. Each stave has a 4V4 rib that adds
still greater strength. Each stave has a concave and convex
edge and a lock on the ends. The staves interlock when erecting.
The Playford staves are five times stronger than the ordinary

stave. Absolutely waterproof.
Outside pointing prevents the
staves from "checking" and re-
lieves the strain on the staves,
thereby making it unnecessary
to double-hoop. Hoops can't sag.
The Playford Silo embodies the
latest, up-to-date knowledge and
experience in silo building. Be-
ing a new silo, we are not forced
to cling to old ideas. We pro-
duce a silo that is strikingly dif-
ferent. The Playford will enable
you as a contractor to offer an A
No. 1 business proposition to the
farmer.

OUR PROPOSITION — Be the con-
tractor who will be able to give
the farmer a real business propo-
sition. The demand already ex-
ists— trade will come to you
easily and quickly. There is 12
solid years of silo experience be-
hind our proposition. We have
plenty of capital and the equip-
ment to "make good" in every
direction. It's the broadest and
most workable kind of a deal
ever put out. Now is the chance
to secure the choicest territory.
Write to-day.

Interlocking Cement Stave Silos

Interlocking Cement Stave Silo Company

414-17 FLYNN BLDG. DES MO1NES, IA.

The inventions used and developed by this Company make It possible
for our lessees to construct concrete silos, water-tanks, and other build-
ings, of any desired size, and to sell them to the farmer at a price which
approximates the cost of an ordinary good wood structure. This is only
possible because of the great simplicity of our system, and the fact that
we only use one stave in any construction, regardless of whether It be a
silo eight feet in diameter, or twenty-eight feet. Our system does not
require a manufacturer to keep on hand a number of different sized staves
to be used in different sized structures, and therefore this not only simpli-
fies his business, but reduces the up-keep expense to a minimum. One
of our machines is capable of constructing five hundred staves per day,
and each stave is just as perfect as is the gearing of a watch.

The erecting of a silo, or any other structure requiring a multiplicity
of these staves, is as simple as is the mating of toy building block* by a

child. This is made possible by the absolute perfection of the machine
which we use for the manufacturing of our staves, a cut of which is
shown herewith.

Our INTERLOCKING feature is such that there Is not a Joint in our
completed structure, but that is strengthened by an encircling band, and
this is accomplished with a lesser number of bands than Is used by any
other construction known. We will give you a full and satisfactory guar-
antee concerning everything regarding our system.

If you are desirous of engaging in a business which Is the llveat and
most flourishing business there is in the country today, and want a proposi-
tion which will pay you a larger percentage on your money than you can
receive from anything else, write us today, and we will thoroughly explain
our proposition.

Forms for Monolithic Silos

MARTIN CONCRETE FORM CO., Ottawa, Kan.

Product We are manu^act;urers °^ the Martin Steel Forms

for Monolithic Silos; also Culvert Forms in Circle

Arch and Flat Top Patterns.

Descrintion The Martin Sil° Form is made of sheet 8teel

*-. which is held in place and adjusted to either

12, 14, 16, 18, and 20 foot diameter sizes. The adjustment is made
by means of turn-buckles. The form is held in place by angle irons
radiating from the center and braced from the bottom to the top
of the form. The form is raised by means of jacks used on the
upright reinforcing rods.

Adaptability

When you buy a Martin
Steel Form for Mono-
lithic Silo work you are
buying a form that has
all the good features of
other silo forms and one
other feature that gives
you the advantage over
users of other makes.
This feature is its ad-
justability. With a
Martin Form you can
build silos of five differ-
ent dimensions. It is not
iifct-ss.-ti-y to have live
separate equipments.

a Martin Steel Form in hand, your
opportunity is assured. Its wide range, its
perfect operation and its uninterrupted success is bound to help
you in the silo business. Eemember one investment in Martin
Forms puts you in a business where others have invested money for
new forms every time a new size silo was in demand.

Let us send you our catalog and prices. We are certain they
will interest you.

Ask About Our ADJUSTABLE CULVERT FORMS

Playf ord Cement Stave Silo

Cement Stave Silo Company Des Moines, la.
Patentees and Manufacturers

Product

A system of erecting silos of cement staves which
enables you to build them in any diameter and height

at a lower cost than any other permanent silo, and a system for

making the cement staves.

yi . .. The machine for mak-

UescnptlOn ing. the cernent staves

is on the order of a block machine, is

portable and is operated with the same

ease. This machine builds staves 30

inches long-, 10 inches wide, 2% inches

thick with concave and convex edges

that make perfect socket joints.

In construction the PLAYFORD CE-
MENT STAVES are put up vertically, in-
terlocking at the half, with joints her-
metically tsealed and reinforced every 15
inches with steel hoops on the outside:
This makes a smooth, thin, rigid, air-
tight and strong enough wall to with-
stand load and storm pressures, and
frost. Open joints are allowed every 10
inches for expansion and contraction to
eliminate cracked walls from heat or
frost.

Advantages™^

PLAYFORD CEMENT
STAVE you do not
limit your operations
to silos only. Water
tanks, utility houses,
culverts and even
straight-wall barns
are built with these
staves. Don't you see
your opportunity here?

Opportunity

chance to make
money. Better write
us for particulars and
terms on our STAVE
MACHINES.

Playford Cement Stave Silo is the Kin* of Silos— Ask the farmer

The HOBBS

Block Machine

Will Do More

and
Better Work

Success comes to the
block maker who is
prepared to fill any order
for any building. You absolutely must have a
machine that makes a great variety of sizes at small
expense. Recognize the wisdom of discarding the
old and installing the new machine if it will do
more and better work.

Order a Hobbs on trial and if it is not the best built block
machine you ever saw, if our composition plates do not make
the most natural rock face, if it is not the fastest to change
and operate, if it will not make the wettest block, if it is
not entirely satisfactory, then return the machine and we
will not only pay all freight, but your cartage as well.

First get our catalog.

THE HOBBS CONCRETE MACHINERY CO.

1445 West Boulevard DETROIT, MICH.

Lansing Company

LANSING, MICHIGAN

WAREHOUSES

NEW YORK
288-289 West St.

CHICAGO
169 West Lake St.

MINNEAPOLIS
330 North First St.

KANSAS CITY
1415 West 10th St.

SAN FRANCISCO'

338 Brannan St.
PHILADELPHIA

Willow and
North American Sis.

BOSTON
78 Cambridge St.
Charlestown Dist.

Branch Factory
PARKIN, ARK.

— Lansing Dove Tail Silo Block Machine.

A machine designed to make blocks of unusual strength
to resist the pressure of the ensilage.

Is furnished in almost any diameter wanted, being made in
12, 14, 16 and 18-foot sizes, and the blocks for any of these sizes
can be spaced a little differently for making larger or smaller
diameters. For example, the 14-foot size will answer for 12, 14
and 16-foot diameter.

Mn*»liinn — *'s made of heavy gray iron castings, consisting of
iu<H.iiinebage and moid. The mold consists of two end plates,
face plate and back plate and cores. A complete outfit is fur-
nished, including sample pallet, tamper and striker for leveling
the blocks.

Two different size machines are made — 8x9x16 and 8x10x16.
We recommend the 8x10x16 for larger size silos. Both machines
make blocks 7% inches high, and eight wide and 16 inches long.
Onarafi/in — Tne operation of producing a block on our Silo Block
ujierdiiuil machine is very simple. All you have to do is to
operate it like any block machine.

Showing the inter-tier and inter-block
tie used on our silo blocks.

~~ The reinforcing of the blocks is provided for in the
manufacture of the blocks, the finished block having
grooves across the top in which wire reinforcing is placed.

It will be noticed that the dovetail opening sets over a small,
round opening and into this opening is poured >soft cement. When
this hardens, it thoroughly binds the different tiers of blocks, as
well as each individual block, together into a continuous concrete
silo. The combination of the three reinforcements makes it abso-
lutely the strongest and best silo on earth, having the advantage
of hollow wall with the strength of the solid wall.
BomavL-e — The Lansing Dovetail Silo Block machine is made of
ivcnicu ivs the best grade of materials and guaranteed t be free
from defects due to faulty material or workmanship. Further
details and prices furnished on request.

Peerless Silo Molds

Monolithic Concrete Silo Build-
Ing is highly profitable if the
right equipment is used. The
RIGHT one is the one with the
largest daily capacity, making
the greatest possible speed with
the least effort and least possi-
ble expense. This is accomplished
with a Peerless Silo outfit, the
ORIGINAL Steel Molds for silo
building.

The principal advantages of
the Peerless System and Molds
are:

1. A CHUTE CONTINUOUS
WITH MAIN WALL. See U. S.
Letters Patent No. 1,122,329.
Other patents pending.

2. FLEXIBLE TYPE of molds
— adjustable to different diame-
ters but retaining the rigidity of
a, standard mold.

3. UNIQUE SIMPLICITY of mechanism and operation; elimi-
nating all cumbersome or troublesome equipment such as center-
mast, guy ropes, wires, etc.

4. SALES METHODS, (a) We GIVE you EXCLUSIVE RIGHT
to build Peerless Silos within a specified district. This valuable
concession costs you nothing:. The only molds sold on this plan,
(b) We sell an interest in molds and build in partnership with
option to purchase our interest.

5. We use the same equipment we sell.
WRITE US FOR PEERLESS PARTICULARS.

%' Daily Capacity Mold;
Capacity, 2 Rings 3' each.

Monolithic Concrete Barn and Silos, Lexington, Ky., Built with
Peerless Silo and Wall Molds.

New Enterprise Concrete Machinery Company

910 First National Bank Bid*.,

CHICAGO, ILL.

Hoosier Silo Extension Roof

AND METAL CHUTE

Sheet Metal Specialty Co. Goshen, Ind.

Manufacturers

Product ^ metal sil° r00^ which can be opened up out of the
^— ^^— way, when filling the silo, and when so opened forms
an extension to the top of the silo, which takes care of the settling
of ensilage.

Descrintion The roof consists of three
inscription parts. a base> a double

section segment and a single section seg-
ment. The base is fastened to the silo
by means of strap irons. The segments
are made of crimped galvanized sheet
metal and both single and double section
segments are hinged alternately to the
base. The double section segments have
two wings hinged on each side, which fold
one inward and the other outward. When
opened and locked they form a complete
circle, like shown in illustration.

Roof Open

The farmer 'once shown
will see these p,0intlS in

favor of a HOOSIER roof:

A roof that is not in the way when
filling the silo.

A roof that makes it possible to use
all your silo.

A roof that will fit any silo and work
satisfactorily.

A roof that measures the same on the
inside as your silo, therefore; the silage
is the same volume as that in your silo.
A roof that is void of cross arms
and braces to hinder your silage
from settling.

R*»marlr«Tne HOOSIER SILO

nemarKS EXTENSION ROOF win

help cinch the sale of a silo. Just
try it on the next farmer and see
how interested he'll become. Only
men like him will appreciate the
value of this roof, because you <give
him more for his money.

Better get posted on this HOOSIER
SILO EXTENSION ROOF, Mr. Con-
crete Silo Builder. It will help you
wonderfully in your business. Ask
for our catalogue.

The HOOSIER Roof is not only right in theory but Guaranteed Practical

Buckeye Silo Roofs

Gambrel Roof With Dormer Window.

We manufacture a full line of sheet metal equipment for
concrete silo, such as Gambrel, Third Pitch and Extension
Roofs. Also Metal Chutes, Ladders and Ladder Rungs.

Buckeye All Steel Silo Door For Concrete Silos

MANUFACTURED BY

The Thomas & Armstrong Co.
London, Ohio

For sale by
B. L. BEVINGTON MCH. CO.

549 W. Washington Blvd. CHICAGO, ILLINOIS

— AND —

THE PIERCE CO.
1102 Waldheim Bid*. KANSAS CITY, MO

"MEDUSAIZE" YOUR SILOS

BY USING

Medusa Gray Portland Cement
Medusa Waterproofing
Medusa Waterproofed Cement

YOU want your silo to last for generations
and you want it impervious to water and
dampness. When you use Medusa products
you are using the same materials that have
been adopted by the U. S. Government for
coast defense work, breakwaters, etc., and
this should convince the most skeptical of their
superiority. Don't take any chances by allow-
ing "something just as good" to be used.

BUILD OF MEDUSA

AND MAKE YOUR SILO A MONUMENT TO YOUR GOOD JUDGMENT

Write for prices, sam-
ples and illustrated and de-
scriptive catalogs contain-
ing tests and testimonials.

Oandusky I ortland Cement Co.

SANDUSKY, OHIO

On a Bag of Cement
Stands for a Record
of 24 Years of Quality

When you buy lumber you can see the qualityl
for yourself; when you buy Portland Cement,
you must rely on the maker and the dealer.^
There are different kinds and grades of "Port-
land" Cement. Don't risk ruining your job
with poor cement.

ALPHA

THE GUARANTEED
PORTLAND

CEMENT

is warranted by us and by all ALPHA dealers
to more than meet the U.S. Government stand-
ard. The Government has used ALPHA ex-
tensively for fortifications, sea walls, dams, etc.
The ALPHA chemists test the product every
hour, keeping it up to the very top in uniform-
ity, fineness and binding power.

Ask the ALPHA Dealer for further details and for
a copy of the large ALPHA book, showing how to build
silos and make scores of farm and home concrete improve-
ments. If you don't know the ALPHA dealer, write us,
mentioning what you are planning to build. Address
Dept. B.

Alpha Portland Cement Company

General Offices: Easton, Pa., Sales Offices: New York, Chicago,
Philadelphia, Boston, Pittsburgh, Buffalo, Baltimore, Savannah

An Average of 51

visitors each business
day for six months
called at this demon-
strating silo erected by
the Holmes - Harding
Company i n Sioux
City, Iowa, with AT-
LAS PORTLAND
CEMENT.

There seems to be
quite a little interest in
Atlas Concrete Silos —
and with good reason.

THE ATLAS PORTLAND
CEMENT CO.

New York Chicago Philadelphia
Minneapolis Des Moines

Marquette Portland Cement

"The Certified Cement"

A cement of certified
quality for all purposes

Portland Cement is a mined
After the rock -s blasted from

the mine it is conveyed to the surface of the earth, where it
goes through the various processes of crushing, burning, pul-
verizing and curing, until it is ready for sacking. Hourly tests
are made of all raw materials and at different stages of manu-
facture as well as the finished product to insure uniform as
well as the best quality. Every bag of Marquette Portland
Cement is guaranteed to conform to Standard and Government
Specifications; there is a green guarantee tag attached to every
bag; it certifies Marquette quality.

Packages and Territory

strong duck bags or strong paper sacks into the states of
Illinois, Wisconsin, Minnesota, Iowa, Indiana and Michigan.
Prices are quoted by barrel; four bags to a barrel.

on request to anyone interested
in building in the Middle West.
"Building for the Future," a book containing photographic
proof of Marquette achievements.

"Concrete in the Country," the use of concrete on the farm.
"Concrete Silos" information on the building as well as
filling of silos.

Marquette Cement Mfg. Company

Marquette Building CHICAGO

EVERY BAG OF MARQUETTE IS GUARANTEED

The Ideal Hoists

Reversible or Non- Re versi b le

Made by

UNIVERSAL HOIST & MFG. CO.
605 State St., Cedar Falls, Iowa

PRODUCT — We are manufacturers of the world known Ideal Hoists.
Made in sizes and styles suitable for all purposes. The
hoist described here is most suited for silo construction.

DESCRIPTION— The Regular Ideal Hoist is mounted on an 8-foot
frame equipped with friction band brake and ratchet
brake, adapted for direct hoisting, single platform elevator, derrick,
etc. It will handle loads up to 1500 pounds.

OPERATION — Ideal Hoists 'are equipped to be operated with any
make of Gas Engine, motor or other power; driving
sprocket wheels and chain, or belt wheel for belt drive furnished free.
They can be mounted up with a concrete
mixer or other machines and connected
to the same engine, so that it is not necessary
to buy an extra engine to operate the
hoist. The simplicity, ease of operation
and reasonable price of this hoist has
made it very popular among contractors
who specialize on small buildings, silos, etc.

30 DAYS' FREE TRIAL

— All Ideal Hoists are
shipped subject to ap-
proval after 30 days
trial. They are guaran-
teed to fulfill the re-
quirements in every
respect. There i s n o
risk in placing your
order for an Ideal Hoist.
It is a valuable addition
to any contractors'
equipment — soon pays
for itself in the saving
of time, labor and ex-
pense.

REMARKS— Further information in regard to a hoist for any particu-
lar kind of work will be gladly furnished. We build
them in all styles and sizes. Ask for our Catalog and prices and
state what work you want to do with a hoist.

The Low Down

Concrete Mixer

ACCURATE
AUTOMATIC

The feeding device on this machine is positive,
accurate and automatic. The materials are forced
into the mixing trough in accurate proportions and
even, continuous, unbroken streams which guaran-
tees a finished concrete of even texture without
weak or lean spots. This kind of a mixture is
highly essential in all concrete silo construction.
This machine has a capacity of from 4 to 12 cubic
yards per hour. It is constructed entirely of mal-
leable iron and steel. Has a mixing device so de-
signed that the cement is thoroughly incorporated
with the aggregate.

Write for descriptive catalog and prices to

Elite Mfg. Co. Ashland, Ohio

The Knickerbocker Co.

Jackson, Michigan

Mfrs. of

Batch and Continuous
Concrete Mixers

A batch machine
with stationary meas-
uring hopper, equipped
with a hoist for elevat-
ing concrete to forms.

Capacity — 7 cu. ft.
loose materials per
batch.

Power — 4 H.-P. Ideal
or Novo.

Weight — 2,300 Ibs.

Wheels — 16 and 22-
inch.

Capacity of hoist —
500 Ibs.

One man can advantageously operate these machines and produce
sufficient concrete for silo requirements. Where more capacity is
desired, put on another man. Machines furnished with wagon
tread when required.

No. 9 Coltrin — A contin-
uous machine that has
mixed concrete for every
country requirement.

Capacity — 8 cu. yds. per
hour.

Power — 3 H.-P. Ideal or
Novo.

Weight— 1,900 Ibs.
Wheels — 22 and 30 inch.

Our Machines Combining

Portability — Durability — Dependability

Quickly Save Their Cost

The Knickerbocker Co.

MINSTER

Batch Concrete Mixers

are for

Silo and Farm Work

they are

Handy — Rapid — Economical

Low Price— High Quality

Mixes sand, gravel or crushed stone, wet, dry or any way
concrete is wanted.

Easily moved from place to place.

Built of best materials, and made for hard continuous service.
Fully guaranteed. The best machine you can get for your
work. Write today for full particulars and prices.

THE CUMMINGS MACHINE CO.

SffiS

FOR SILO WORK

the two mixers illustrated on this page have fully met
the exacting conditions of good concrete silo construction,

The Eureka
Batch Mixer

holds 5 to 6 cu. ft. dry
material per batch.
Furnished with Side
Loader, Batch Hopper,
Wheelbarrow Hopper,
h. p. engine operates it.
portability and compact,
construction are commendable features
for frequent moves over rough roads.

The Eureka Continuous Mixer

shown here has a capacity of 5 to 8
cu. yds. an hour. It is well adapted
for silo work, and is widely used for
that purpose.

On account of limited space here
will you kindly ask for catalog and
more complete information.

EUREKA MACHINE COMPANY

112 Handy St., Lansing, Mich.

"The Standard"

Low Charging
Concrete Mixer

The charging
platform of "The
Standard" Mixer is
only 24-inches high
from the ground
and is furnished
with the outfit (see
illustration) which
makes the mixer
easily charged di-
rect from wheel-
barrows. This
does away with the
necessity of building high platforms or the use of dangerous *ir*°
loaders which cause three-fourths of your delays and breakdowns.

The large opening In charging end of drum permits constant
inspection of batch at all times and enables you to determine exact
condition of same before discharging. It is essential to get good
concrete in the construction of Silos, Tanks, etc.

The illustration below shows mixer equipped with hoist for
elevating conciete or other uses and is especially adapted for con-
struction of Silos, Towers, Chimneys, etc. This design provides the
handling of mixed concrete in an elevated position without requiring
a separate hoisting equipment. The mixer and hoist are driven by
the same engine and can be operated together or independently as
desired.

The weight of "The Standard" Low
Charging Mixer is reduced to a minimum
on account of its simple construction, few
working parts, etc., which
allow the outfit to be easily
moved from one location to
another. These machines
are built in capacities of
3 to 40 cubic feet per
batch and complete Cat-
alog Xo. 22SB will be
mailed at your request.

The Standard Scale & Supply Co., Mfrs.

1345-4? Wabash Ave. 243-245 Water St. 136 W. Broadway

Chicago Pittsburgh New York

35 So. 4th St. 1547 Columbus Rd.

Philadelphia Cleveland

The Winner

Model "E" 4 and 6 Cubic Ft. Concrete Mixer
Made by The Cement Tile Machinery Co.

408 Rath St., Waterloo, la.

Description — ^ special concrete mixer with hoist, especially
adapted to silo builders. A simple batch mixer
with an open drum that does the mixing always in sight. Easily
charged and more easily discharged.

The Winner was primarily built to answer the requirements of
the silo contractor. It is light and handy to move through the
country from one job to another, has the mixer and hoist all com-
bined in one machine. Hundreds of operators in all parts of the
country have placed their O. K. on this type as a silo rig. It is so
simple and efficient

The Winner
will mix con-
crete as well as
the best mixer
on the market
and the hoist
will not be in
the way, or
bother the oper-
ator when the
mixing is being
done. The hoist
can be used sep-
arate, or the
mixer separate,
or both together

and neither one will interfere with the work of the other. You
couldn't buy a separate hoist for anywhere near the price we ask
for this neat, efficient and durable little rig.

Write for our Catalog and Prices.

The Winner

With or Without Hoist
4 or 6 Cu. Ft.

The Hoist is a single drum, non-reversible type.

Anderson Rotary Mixer

It's a One Man Control

W. H. Anderson Tool & Supply Co.

182 Brush Street, Detroit, Michigan

Arlantahilitv Tne Anderson Rotary Mixer is without question
/\Ud|liauillljr tne begj. an(j most economically operated con-

crete mixer on the market today, particularly adapted to the
contractor who wants a portable machine for silo or other small
jobs requiring a capacity of 75 to 80 cubic yards per day.

The Anderson Rotary Mixer is a one man con-
trol. The operator has full control of side

loader, water and discharge. Mixer is furnished with wheelbarrow

or batch hopper, or side loader, as desired. Also with or without

hoist. Frame and truck are

made of steel. Drum is 36

inches in diameter, is con-
structed with heavy cast iron

heads, with slop rings on

loading and discharging ends

cast integral with head to

prevent wasting or slopping

of material. Wheels are pro-
tected by mud rings from

grit and mud. The blades of

the drum are so arranged to

give a thorough mixing of

the materials in a minimum

amount of time. Has a steel

driving gear of solid forged

steel with hardened roller

steel chain. Novo Engine.

Guarantee

The Anderson Rotary Mixer is guaranteed
against defective material of any kind, but not
the replacement of broken parts when these parts are broken by
carelessness. We will replace any defective part if said part is
forwarded to us, prepaid carrier, for our inspection.

We have studied very carefully the conditions and
^G methods of the contractors, being in the con-
tractors' supply business for 44 years, and we are offering this
machine to you backed by our guarantee, experience and reputa-
tion. All these features mean a great deal to contractors in the
saving of wages alone. The one man control feature alone will
save 5 to 10 dollars per day in expenses and greatly increase the
output.

Ask for the Anderson Rotary Mixer Bulletin 107E.

Jaeger Big-an-Litle Mixer

_ "A Mix a Minute Kind" _

Made by THE JAEGER MACHINE CO.,

217 Rich Street Columbus, Ohio

RHV

puy

a

a

for or desire

and you will enjoy every pos-
sible advantage you could ask
a mixer, especially a mixer for silo or other
^ small construction work. It

mixes a batch a minute —
5 to 6 cubic feet — mixing
always open to thft eye.
Charging and discharging
is the simplest of its kind.
Its hoist attachment is in-
dispensable for silo work.

If you want an efficient,
economical and portable
mixer, get a Jaeger "Big-
an-Litle."

The Drum, of conical-shape, rests on the yoke
and revolves around the axis, which is held by
yoke at an angle. The power to rotate the drum is taken from the
drive pinion, which has its bearing in the center of one end of the
yoke, making it possible for the drum to be discharged while re-
volving. The Power to drive the pinion is taken from the engine
by means of gears, which thus produces a positive drive with no
possibility of break-down. The Outfit is of the best mechanical
design and construction. It is rigidly braced to insure greatest
strength, eliminate all strain and withstand long-continued rough
usage, with
p r a ctically
n o outlay
for repairs.

If you want
speed, steady
service and
correct mix-
ing, get a
Jaeger "Big-
A n - L, i 1 1 e
Mixer."

Ask the
man who
uses one.

Catalog Tells Whj

Archer Special

Concrete Mixer

Archer Iron Works

34th Place and Western Avenue

An Ideal Mixer for Silo Construction

The big problem of the silo
builder -and the general con-
crete contractor has been to
obtain a really portable mixer,
not too small in capacity and
yet at a low price.

The Archer Special Concrete
Mixer supplies this want in
every respect. The placing of
the weight of the heavier parts
of the machine over the wheels
allows the mixer to be easily
lifted at the platform end and
moved around on the job
without trouble.
When moving from
one job to another
simply hook the
platform end onto
the back end of a
wagon and "you're
off." For Silo
building the mixer is
specially provided
with a hoisting drum
direct connected to
the countershaft.

The mixer has a
capacity of 4% cubic feet of wet concrete per batch or 6 to 7
cubic feet of dry material. This allows a daily capacity of 50 cubic
yards which Is the amount we guarantee, although many contractors
have greatly exceeded this amount.

The Archer Special mixer is not only adapted to Silo Building but
is particularly fitted for all classes of concrete work such as Founda-
tions, Sidewalks, Concrete Roads, Culverts, Bridges, etc. One of
the chief advantages of the mixer for general work lies in the End
Discharging feature, which makes it possible to spout concrete direct
into the forms in most cases thus saving the cost of wheeling.

The End Discharge together with the Portability or easy mov-
ing feature gives the machine a special advantage over most types
of small mixers intended for use on jobs running up to 3,000 cubic
yards or less. While mixing costs vary according to the layout of
the jobs, the average labor cost with the Archer Special has been
determined to range around 40 cents per cubic yard of concrete
mixed and placed.

Full particulars and prices, write for catalogue E, furnished on
request.

The Logical Mixer for Contractors

THOROUGHNESS

Concrete in Silo Construction MUST be Thoroughly Mixed.

The Blystone Shovels, which insure absolutely perfect
mixing of concrete or mortar. Handle dry or wet, coarse
or fine material.

The open drum enables
the whole mixing opera-
tion to be watched and
controlled. Extremely easy
to clean. No attachments
to eat up power and get
out of order. Every ounce
of power mixes.

Hopper & Son, Manhat-
tan, Kansas, say: "We

now have in use five of
your mixers building silos.
We find it a very conven-
ient mixer for this pur-
pose. We are especially
concerned in a thorough
mix, light weight for trans-
portation and moderate
price. In all these re-
spects your machine fills
the bill."

OVER 1300 BLYSTONES NOW IN USE
INVESTIGATE AT ONCE

BLYSTONE MFG. CO.

140 Second Street Cambridge Springs, Pa,

17 C - I ^ \\7* +*• L* Take the M ajority

r or olio Work choice— the

WONDER MIXER

with AUXILIARYl HOIST

Specially designed for Silo builders, this combination has also
proved the most popular all-around mixing and hoisting outfit on the
market. It is extensively used by chimney builders, where condi-
tions similar to those obtaining in silo work are met. It is simple,
strong and dependable, and only 12 inches longer than our standard
LITTLE WONDER "FIVE" mixer, and the hoist adds but 200
pounds in weight.

The WONDER has 2% h. p. gasoline engine and lifts 700 pounds
at 45, or 500 pounds at 60 feet per minute. Where heavier loads
are to be hoisted, we equip with 4 V& h. p. engine. Cable capacity
250 feet of %-inch cable. Hoisting drum has ratchet and pawl for
holding load at rest, or, by means of the brake it can be "spotted"
at any point desired. Side Loader can be added to this machine at
time of purchase if wanted.

The Secret of Success

in silo building is the density of the mix — its air and water tight
quality. Two concerns are each using 40 WONDERS, and several
20 or more for this reason, and thousands of contractors throughout
the country testify to WONDER superiority in every essential point
of mixer construction.

Send for Our Special Trial Offer

and catalog of "The Mixers That Make the Money" before deciding
upon any mixer.

Branch offices and distributing: depots in New York, Philadelphia,
Chicago and a dozen other large cities, also 100 agencies. Write for
(lie nearest to you.

WATERLOO CEMENT MACHINERY CORPORATION

125 VINTON ST., WATERLOO, IOWA

Mfrs. Concrete Mixers, Traction Paoers.Trench Fitters and Contractors Equipment

Simplex Continuous Concrete Mixer

This machine combines the rolling principle of mix embodied in
all Batch mixers, with an absolutely accurate measuring device
and positive force feed. The revolving cylindrical drum is slightly
tilted, which allows for a rolling mix and gravity discharge. The
material is fed into the mixing drum through a three compartment
hopper equipped with a measuring device and force feeding attach-
ment which are graduated for any desired proportion. The drum is
sixty inches long, and on account of the slight tilt, the material
falls two inches toward the discharge end with each revolution.
Water is applied eighteen inches from the discharge end, providing
for a 21 time dry and a 9 time wet mix before the material is
discharged. The capacity of the machine is regularly from one to
ten yards per hour, which may be increased to twenty yards per
hour. It is equipped with 3 h. p. engine.

Simplex Batch Mixer

This machine is constructed after standard principles, the drum
having special cast heads, with eight gauge boiler plate steel shell.
It is equipped with regular or batch hopper, and made in either
side or end discharge type. Capacity, eight cubic feet, dry mix.
It is equipped with 4 h. p. gasoline engine.

The Miles Manufacturing Co.

Jackson, Mich.

A Baby Grand on Silo Work

A Continuous Mixer and a Single Drum Hoist Combined

HALL-HOLMES MFG. CO.

509 OAK STREET JACKSON, MICH.

Operation The

- tion gives a
fair idea of the opera-
tion of a Baby Grand
Mixer, with Single
Hoist Drum, used on a
silo job. The contrac-
tors are Arnold Nagel
& Co., Libertyville, 111.

working parts are completely enclosed in
them from grit and dirt.

Description The

- Grand
Mixer is universally
recognized as the best
continuous concrete
mixer for all purposes.
It eliminates uncer-
tainty. The first batch
is the same as the
last. It is built for
hard service and the
cost of upkeep is prac-
tically nothing All
steel housing to protect

If >'ou are
bull ding

a silo or
a concrete floor in
the upper story of a
building, a hoist on
your continuous mix-
er enables you to
pour a steady stream
o f concrete. The
hoist is mounted on
the frame of the ma-
chine and operates
with or independent
of the mixer.

Testimonial :T..1;

bought

for my Baby Grand
has given perfect
satisfaction. Yours
respectfully, J. L.
Irving." General
contractor and build-
er of Area, Lake
County, Illinois.

ASK FOB CATALOG

IDEAL Concrete Silo Block Equipment

Ideal Concrete Machinery Co.

1304 Mo n mouth Ave.
Windsor, Ont. Cincinnati, Ohio

THE PRODUCT— We are manufacturers
of the famous IDEAL Concrete Block
Machinery, both for silo work and
straight walls.

THE MACHINE— The illustration in
the center of the page shows the
IDEAL Model "A" Silo Block Ma-
chine, which makes blocks for silos
having a 5-foot, 7-foot or 9-foot radius.
Any standard
face design can
be used. The
machine is sim-
ple in construc-
tion and swift in
operation. The
same machine
can also be used
in making blocks

THE SILOS—

The silos possess
every advantage
of monol i t h i c
construe tion
with the addi-
tional advant-
ages of hollow
wall construc-
tion, which in-
sures a more
even temperature
inside the silo
and is a great protection for ensilage in freez-
ing weather. Ideal Silo Blocks have a very
practical arrangement for placing the rein-
forcing (see diagram). Every block is perfect
and true to curvature inside and out and can
be inspected before placing in the wall.

LITERATURE — It will pay you to get our
literature and specifications on the IDEAL Silo
Block equipment. Send for them.

"IDEAL"

The most reliable concrete machinery

for houses,
barns, etc.

. ,

C/D

\

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