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HIDES & SKINS

AND THE

MANUFACTURE OF LEATHER



A LAYMAN'S VIEW
OF THE INDUSTRY



BY

JAMES PAUL WARBURG

Assistant Cashier
The First National Bank of Boston



The First National Bank
OF Boston






Copyright, 192 i
The First National Bank of Boston



Z'




CU621335



'I QO 1021



JUL 2:



\3^



^ TABLE OF CONTENTS

rj^ ^ Foreword

{^ The Evolution of The Industry

Part One

The Raw Material

Chapter i. Hides.

Chapter 2. Skins.

Chapter 3. Flaying and Curing.

Chapter 4. Imperfections.

Chapter 5. The Manufacturing Materials.

Part Two

The Manufacture of Sole Leather

Chapter 6. The Preparatory Processes.

Chapter 7. Vegetable Tanning of Sole Leather.

Chapter 8. Finishing Sole Leather.

Chapter 9. Other Heavy Leathers.

Part Three

The Manufacture of Upper Shoe and Dressing Leather

Chapter 10. Calf-skins for Upper Shoe Leather.

Chapter 11. Side and Patent Leather.

Chapter 12. Goat-skins and "Kid" Upper Leather.

Chapter i3. Other Upper Leather.

Chapter 14. Oil Tannage of "Chamois" Leather. ,

Chapter i5. Tawing Glove Leather.

Chapter 16. Book and Bag Leather.

Part Four

The Economic Distribution of The Industry

Chapter 17. The World's Supply of Raw Material.

Chapter 18. Imports of Raw Material into the U. S.

Chapter 19. Exports of Leather from the U. S.

Chapter 20. Marketing and Prices.



The First National Bank of Boston

is a substantial stock-holder in

The International Acceptance Bank Inc.

3 1 Pine Street, New York City

This bank has recently been organized to finance foreign
trade. Over one third of its $i5,25o,ooo. Capital and Sur-
plus is owned by the foremost European Banks and bank-
ing firms, a unique feature, which enables this^new insti-
tution to offer unparalled service in foreign fields. Among
its stock-holders are also many of the leading banks of the
United States.

Paul M. Warburg D. G. Wing F. Abbott Goodhue
Chairman Vice-Chairman President



ILLUSTRATIONS

FRONTISPIECE page
Inspection of Cattle before killing _ _ 6

PART ONE. The Raw Material.

Flaying Hides from Cattle - - - 19

PART TWO. The Manufacture of Sole Leather.

Sorting Hides before Washing in Drum Tumbler 26

Soaking and Liming Pits with Crane Conveyor 26

Unhairing - - - 29

Fleshing - _ - _ _ 3q

Trimming on the Beam - _ _ 31

Working Cylinder of Fleshing Machine {Drawing) 31

Pit Tan Yard - - - - 32

''Rounded" Hide, two Methods (Drawings) - 34

Bleaching - - _ _ _ 37

Oiling - - - 37

Setting - Out - - - - 37

Rolling - - - 38

Brushing - - _ _ . 33

PART THREE. The Manufacture of Upper-Shoe and Dressing

Leather.

Sorting Skins - - - - 42

Paddle Vats - - - - 42

Chrome Tanning Wheel - - _ 44

Shaving Machine - - - _ 45

A Row of Fat-Liquoring Drums - - 46

Slocum Staking Machine - - _ 49

Baker Staking Machine (Grasshopper type) - 49

Straining _ - - _ _ 59

Seasoning and Drying - - - 50

Mechanical Foot Counter - - - 52

Sorting and Making Bundles - - 52

Feed End of Splitting Machine - - 54

Delivery End showing two Splits - - 54

Setting out Side Leather - - - 56

Straining Side Leather - - - 56

"Toggling" before Japanning - - 57

Varnishing Room, Showing Ovens - _ 57

Boarding the Grain - - - 61

Pressing Sheep Skins - - - 63

Glazing Machine - - - - 65

Serial Table Unhairing Machine - - 68

PART FOUR. The Economic Distribution of the Industry.

Exports of Leather - - _ 74

Price Fluctuations (charts) - _ _ 79




s^






FOREWORD

The Evolution of the Industry

Probably every man who has ever seen leather knows it to be de-
rived from the skin of various animals; but probably not one in ten
even thinks that he understands just what has happened to the raw
skin to make it leather; and, as a matter of fact, scientists are to this
day divided in their opinions as to whether the change caused by tan-
ning is chemical, or physical, or both. The twofold object of all
tanning processes is to render the skin imputrescible and more or less
elastic. The origin of how this was first accomplished cannot be traced,
for the attempt to preserve the skins of animals dates back far beyond
recorded history into the time of primitive savages. Specimens of
ancient Egyptian leather, said to have been manufactured at least a
thousand years before the birth of Christ, are still to be seen in a
museum in Europe, and it is probable that the inhabitants of the Nile
delta at that time were fully as versed in the art of tanning as were
our ancestors in the reign of Queen Elizabeth.

We may picture to ourselves an early savage, wearing a dried pelt
of some animal as a cloak. We may think of him at first surprised,
and then considerably annoyed to find that the softness of the skin
entirely disappeared as soon as it was thoroughly dry, giving place to
an exceedingly disagreeable horniness. His first reaction would be to
soak the skin in water in an attempt to render it once more supple.
It was probably in this way that the natives of Japan discovered that
the waters of certain streams had a softening and preservative effect
upon skins, for they flowed over a bed-rock of alum. Until very re-
cently Japanese white leather was produced in this primitive manner.

Failing such a fortunate freak of nature, our savage would find to
his chagrin that as soon as his pelt had dried, it became once more
hard, and furthermore began to show signs of decay. We may picture
him then trying the effect of animal fats, or perhaps of smoke, or in
some way discovering the preservative effect of twigs and pieces of
bark. In any one of these ways, provided it were continued long
enough, he might obtain a rudimentary tannage. To be sure, he would
be far from producing a leather that could be made into a modern



^n



shoe, but nevertheless he would possess a skin practically immune from
decay, and softened to a certain degree.

The progress in the development of leather manufacture until
mediaeval times was comparatively negligible, and historical data are
lacking by which to trace its course. We know, however, that by the
end of the sixteenth century the manufacture of curried leather was
well established in Hungary, and that Spain was at that time producing
a fair quality of morocco. Gradually the industry spread over Europe,
America, and other parts of the world; machinery was slowly per-
fected to take the place of manual operations; new finishes, such as
waxed calf and alum-tanned kid, were added to the old Spanish crup
and cordovan leathers; and finally, about thirty years ago, scientific
chemistry evolved the chroming process, by which it is estimated that
ninety per cent, of the world's upper shoe leather is made to-day.

The remarkable feature of the industry, even now, remains the fact
that it rests primarily on an empirical basis, far more so than any
other of our primary industries. While it is probably true that medi-
cinal herbs constituted the first chemical discovery of man, it may well
be claimed that industrial chemistry, to which our present civilization
owes so many of its material adjuncts, originated in the preservation
of animal skins.

Besides the usage of leather for boot soles and uppers, there are an
infinite number of purposes to which it has been adapted, some of
which it will be impossible to treat here in even a cursory manner.
It is not intended by these omissions in any way to belittle the im-
portance of the subjects which the author has felt to lie beyond the
scope of this pamphlet. Furthermore, in order to avoid duplication,
the arbitrary expedient has been adopted of discussing in Part Two
only the vegetable tannage of sole leather, and in Part Three only the
chrome process for making upper boot leather. In this manner each
method of tanning is taken up in detail in the field where it finds its
greatest application, but it must not be inferred by the lay reader that
sole leather is never chromed, or that no upper leather is made by the
vegetable processes. While this fact is brought out later on, it cannot
be too strongly emphasized at the outset.

To attempt a discussion of the entire industry within so brief a space
is at best a precarious undertaking. For purposes of simplification the
subject has been divided into four groups: 1. The Raw Material; that
is, hides and skins, what they are, where they come from, how they are
obtained, and their imperfections; also the materials by means of which
they are made into leather. 2. The Manufacture of Sole and other
Heavy Leather. 3. The Manufacture of Boot Upper, Glove, Book, and
other Light Leather. 4. The Economic Distribution of the Industry.



18|



Each of these groups is in itself a subject for a book far longer than
this.

The illustrations contained in this booklet were made available
through the courtesy of A. C. Lawrence Leather Company, Howes
Brothers Company, Swift and Company, Turner Tanning Machinery
Company and the Associated Industries of Massachusetts. To these
and many other friends of The First National Bank of Boston in the
leather industries the author is indebted not only for helpful advice
and criticism, but for exceptional opportunities for first-hand observa-
tion. Much of the material contained in subsequent pages has been
derived from other books and articles, especially from Mr. K. J.
Adcock's admirable study of the industry, and valuable assistance was
received from various trade publications. Finally, too much credit can-
not be given to Mr. Perry D. Keating, of the staff of The First National
Bank of Boston, for his assistance in much of the research work and
compilation of statistical data.

Boston, Mass.
April 19, 1921.



The First National Bank of Boston

jointly with the National Bank of Commerce in New
York owns 5o% of the stock of

The French American Banking Corporation

New York City

This corporation is owned by banks whose combined
resources are over $i,3oo,ooo,ooo., the largest interest, 5o%
being held by the Comptoir National d'Escompte de Paris.

Through this connection the corporation can avail itself
of over 225 branches in France, England, Spain, Egypt,
Tunis, Madagascar, Australia, and India. The Comptoir is
also the Paris and London agent of the French Colonial
Banks in Algeria, Morocco, Indo-China, East Africa, Mar-
tinique, Guadaloupe, and French Guiana.



PART ONE

THE RAW MATERIAL



CHAPTER I



Hides

The hides and skins of various animals form, as we know, the raw
material from which leather is manufactured. The term, "Hides,"
is applied to coverings of the larger animals, such as full-grown cattle,
horses, or buffalo; while technically "Skins" are derived from smaller
animals, for example, calves, sheep, or goats. The intermediate size
between a large "skin" and a small "hide" is known to the trade as a
"kip." This term, however, is not very clearly defined, being used with
various meanings in different parts of the world. Where the pelt of a
wild animal is dressed, the furrier always refers to it as a skin, no
matter what the size of the animal.

The heavier grades of hides are generally manufactured into sole
and belt ing leath er; those of extra large surface — "spready" hides —
are oTlen used f or~upholstery ; and in some cases, as we shall see later,
hides are split into several layers or thicknesses, and by this means
used for the production of boot uppers of a variety known to the
trade as "Side Leather." As a very general rule, one may say that
hides, because of their greaTe^ thickness, are particularly_^ the raw
material^oLt he sole and- iieavy leathgr tan ner, while skins go na,turally
Tnto the process of makingjip^er . shoe, bag^ and glove leather. In-
asmuchTas these'^wo industries are entirely separate and distinct, it
will be advantageous to the reader to bear in mind this segregation
from the start.

The hides used by sole-leather tanners in this country are of both
foreign and domestic origin. The chief source of imported hides are
the meat-freezing plants of South America, which of recent years have
become a dominant factor not only in the world's supply of beef and
mutton, but of hides and sheepskins as well. South American packer
hides are known to the trade as "Frigorificos," and are preferred by
many tanners over all other varieties. South American green-salted
hides from smaller killing-plants are known as "Saladeros" and "Mat-
aderos." Some hides are imported also from other countries, and they
are used both for the manufacture of sole and upper leather. South
Africa and Australia produce large quantities of first class hides, but
imports into the United States from these sources are not very heavy.



"Hides'

"Skins"
"Kips"



Skins for

Upper

Leather



Foreign
Hides



il3l



Domestic
Sources



Classifi-
cation



East India hides, often known as kips, because of the small size of the
Indian cattle, China hides, Russian horse, and Javanese water-buffalo
hides also find their way to this country in smaller quantities.

As might be expected, the chief domestic supply is derived from the
great meat-packing establishments of the Middle West, "Packer" hides
not only dominate the markets in this country, but exercise a strong
influence on hide markets throughout the world. Quite a large supply
also comes from the smaller abattoirs in various cities, and to these
must be added a considerable number obtained from local butchers
throughout the country. Both "City" and "Country" hides, which com-
pare to "Saladeros" and "Mataderos," command a lower price than
"Packers," because they are not as a rule so well taken-off or cured.

All hides are bought and sold on a basis of so many cents per pound.
They are classified by: 1. Geographical origin; 2. Take-off; 3,
Weight and sex of the animal; and 4. Freedom from defects. Thus,
to choose a random example: "Pennsylvania, Country, Light Native
Steer, Free from Grubs." We shall discuss shortly the various defects
which are found in hides and skins, but before leaving the subject of
hide classification, it might be well to glance at a list of those terms
which refer to weight and sex, and to the brand marks.

PACKER HIDES

Heavy Native Steer Free of brand 60 lbs. and up

Spready Native Steer Free of brand 6^/3 ft. across

Light Native Steer Free of brand 50 to 60 lbs.

Extreme Light Native Steer Free of brand 25 to 50 lbs.

Heavy Butt Branded Steer, Branded on butt, not over 18 in.

above butt 60 lbs. and up

Light Butt Branded Steer Same 50 to 60 lbs.

Extreme Light Butt Branded Steer Same 25 to 50 lbs.

Heavy Colorado Steer, Side and butt branded, spready and thin 60 lbs. and up.

Light Colorado Steer Same 50 to 60 lbs.

Extreme Light Colorado Steer Same 25 to 50 lbs.

Heavy Texas Steer, Side and butt branded, smaller and plumper

than Colorados 60 lbs. and up

Steer Same 50 to 60 lbs.

Same 25 to 50 lbs.

Free of brand 55 lbs. and up

Free of brand Under 55 lbs.

Branded 25 lbs. and up

Free of brand 25 lbs. and up

Branded 25 lbs. and up



Extreme Light Texas
Light Texas Steer
Heavy Native Cows
Light Native Cows
Branded Cows
Native Bull
Branded Bull



Buffs

Heavy Cows
Extremes
Heavy Steers
Bulls
Branded Hides



COUNTRY HIDES

Free of Brand
Free of Brand
Free of Brand
Free of Brand
Free of Brand
rft-er^of-^rand



Cow or Bull Hide 45-60 lbs.

60 lbs. and up

25-45 lbs.

55 lbs. and up

60 lbs. and up

all weights



il4|



CHAPTER II

Skins

In the preceding chapter we dealt briefly with the raw material
which is made into sole leather. When we come to consider the var-
ious kinds of skins which are used for the manufacture of so-called
dressing leathers, we are at once confronted with such an array of
different varieties, that, in order to avoid hopeless confusion, it be-
comes necessary to confine ourselves to a few of the most commonly
used.

Calf, goat, and sheep skins form by far the greatest proportion of the Kinds of
skins of smaller animals which are used for making leather. It is well -^^'^
to remember also that cattle hides, kips, and horse hides are extensively
used for making boot uppers and bags. The "shell," or hide from
the buttocks of the horse, is particularly valuable because of its fine
grain, and is made into cordovan leather, while the remainder of the
horse-hide is chiefly used for japanning into so-called "Patent" side
leather. Pig-skin is an excellent material for bag and saddlery leather,
the reason for its limited use being the difficulty of flaying it from the
carcass. Other less frequently used skins are those of the dog, kan-
garoo, alligator, crocodile, seal, frog, chamois, antelope, and various
kinds of deer.

Kips and calf skins are obtained, generally speaking, from the same
sources as hides. The bulk of the calf skins used in this country come Calf Skin
from the Packers, others from outside city and country butchers, while
a large quantity are imported from Europe, South America, India, and
other parts of the world. The Chicago Packers sell their calf skins on
a basis of cents per pound of weight; in most other markets, however,
the skins are graded into groups by weight and then sold on a fixed
price per skin. Different breeds of cattle, the age of the calf and its
condition when killed, as well as the actual condition of the skin itself,
are all factors in determining value. The chief use of calf skin leather
is in making high grade men's boot uppers, and the heavier uppers
for women's shoes.

Goat skins are the material from which are made the well-known
glazed kid uppers for light, high grade men's and women's footwear.
The leather made from these skins is easily distinguishable by its



I15|



beautiful clear grain, which is more uniformly defined than that of
Coat Skin ^^^^ skin. The chief difficulty lies in obtaining skins of sufficient sub-
stance to form a strong leather. Besides uppers many other articles
are made from the skins of these animals; moroccos for book -binding,
glove, bag and upholstery leather, and sundry articles such as purses,
pocket-books, and ladies' belts. Practically no goats are bred in this
country, except in Texas, so that the vast majority of the skins used are
imported from foreign countries. Asia Minor, Spain, Austria, and the
Cape are the chief sources of the kind of skins most suitable for glove
leather, while the best skins for making glace kid are derived from
India, China, Brazil, Mexico, the Cape, and other Asiatic countries.
One of the highest grades, known as Patnas, come from the Indian
province of Behar. The most desirable skins for the manufacture of
morocco are produced on the European continent, particularly in Nor-
way, Spain, and Germany. In this country goat skins are usually
bought at a price per dozen.

Sheep are raised in a great many parts of the world, in fact almost
Q, , . everywhere except in countries where the excessive density of the pop-
ulation has made grazing impossible. Nevertheless good sheep skins
are not as abundant as might be expected. The reason for this is that
these animals are raised primarily for wool and mutton, and that, as
a general rule, the higher the quality of the wool obtained, the less
substantial is the skin. A large supply of domestic sheep skins is
obtained from the slaughter-houses of the Middle West, but a great
number are also imported from Australia, New Zealand, Africa, and
other countries. South America produces tremendous quantities of
sheep, but the skins are sent chiefly to the great pulleries at Mazamet,
France. Sheep skins are used for making the cheaper grades of dress-
ing leathers, and also, particularly those from the Cape, for gloves.
A common practice is to split the skins of these animals, using the
outer, or grain half (the skiver) for glove leather, and the lining for
"chamois" or parchment.

Pig skin yields a leather which, for certain purposes, such as sad-
fig SA;ire dlery, cannot be approached by any substitute. Nevertheless it is so
costly to remove these skins, because of the large quantity of fat that
is lost in the process, that most killers prefer to leave the skin on the
carcass. Scotland and Germany are practically the only countries
which produce pig skin in large quantity. Imitations, particularly for
bags and portmanteaus, are numerous, but are detectible by the absence
of the holes left by the bristles.

We have already mentioned some of the less frequently used skins of
Other other mammals as well as those of some of the amphibious reptiles, and

Animals even fish. Given sufficient incentive, there are practically no skins



116 I



from which some sort of leather could not be made, and it is only
because we have always had an ample supply of cattle, sheep, and
goats, that these have become the standard raw materials for the
leather industry.



117



CHAPTER III

Flaying and Curing

Much The methods by which the hides and skins are removed from the

Inexpert carcasses of slaughtered animals vary a great deal, according to the

Flaying ideas prevalent in different countries. Moreover, a vast number of

butchers still flay in an exceedingly antiquated manner, by which the
hides are rendered practically useless to the leather manufacturer.
Not only do inexpert slaughtermen often misshape the hides, instead of
leaving them square, but frequently they actually cut holes or deep
scores through careless handling of their knives. In many cases this
is due to ignorance, in others to ill-warranted haste. Kosher killing
somewhat reduces the value of a hide, because the entire throat is
slashed.

The French process of mechanical flaying, originally invented about
Modern ten years ago by Gaston Tainturier, is in great favor in Europe, and

Methods produces excellent results, as does also the English method of using
a device known as the tail-extractor. The most efficient systems, how-
ever, are probably those developed by the American Packers, and
more recently by the freezing plants of South America.

Without going into the details of how various kinds of animals are
American slaughtered, the procedure in the American plants is that of hanging
Packer the animal, immediately after it has been killed, by one or both of its

System hind legs. It then travels slowly along an overhead conveyor past a

considerable number of workmen, each one of whom has a specific
operation to perform. Thus, taking the case of cattle, which are first
stunned by a severe blow on the head, the first man, known as the
sticker, performs his task of sticking the throat and allowing the blood
to drain. The "Header" then starts to remove the hide from the head,
the "Leg-breakers" loosen it from the shanks, and the "Floorsmen," or
"Siders," remove the skin from the sides. For this last operation the
animal is laid on its back. After it is once more hung head-down, it
passes in succession the "Rumpers," "Fell-cutters," and "Backers,"
whose names imply the parts of the animal from which they detach the
hide. The process is completed by the "Droppers," who pull the hide
off^ the neck and shoulders, and drop it on the floor for inspection.

The foreman goes over each hide with great care, and if he dis-
covers any cuts or scores, he is at once able to tell from their location



118]



on the hide which workman is responsible. Accurate check is kept Check on
of all mistakes made in the work, so that an inefficient operative does W^orkmen
not last for any length of time.

After the ears have been cut, and the switches trimmed from the
tails, the hides are graded into various selections, such as Branded
Cows, Heavy Native Steers, etc.

Argentine Frigorifico hides compare favorably with those taken off

by the American Packers, and are preferred by most sole leather tan- r- • .r

1 1 1 rn- 1 inii r ngorijicos

ners because they are cleaner, more careiully trimmed, and neshed.

The practice there is to bathe the cattle thoroughly before killing, and
afterwards to wash the hides. The hair side is scraped under a spray
of water and the flesh side severely brushed, after which the surplus
flesh is scraped off. Accordingly there is less waste material on these
hides than on any other kind, and as a rule, they command the highest
price per pound. In the same way "Packers" are given a higher value
than "Cities" or "Countries."

The flaying process varies, of course, with calves, sheep, goats, or


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