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Charles Thomas Davis.

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CX3PYRIGHT DEPOSIT



THE



MANUFACTURE OF LEATHER:



^



BEING A

DESCRIPTION OF ALL OF THE PROCESSES FOR THE TANNING,

TAWING, CURRYING, FINISHING, AND DYEING

OF EVERY KIND OF LEATHER;

INCLUDING THE

VARIOUS RAW MATERIALS AND THE METHODS FOR DETERMINING THEIR
VALUES ; THE TOOLS, MACHINES, AND ALL DETAILS OF IMPORTANCE
CONNECTED WITH AN INTELLIGENT AND PROFITABLE PROS-
ECUTION OF THE ART, WITH SPECIAL REFERENCE TO
THE BEST AMERICAN PRACTICE.

TO WHICH ARE ADDED

COMPLETE LISTS OF ALL AMERICAN PATENTS FOR MATERIALS, PROCESSES,
TOOLS, AND MACHINES FOR TANNING, CURRYING, ETC.



(3 , BY

/ 1

-y^ CHARLES THOMAS DAVIS.

ILLUSTRATED BY THREE HUNDRED AND TWO ENGRAVINGS,

AND

TWELVE SAMPLES OF DYED LEATHERS.



DEC 10 18i4



PHILADELPHIA:
HENEY CAEEY BAIRD & C 07^

INDUSTRIAL PUBLISHERS, BOOKSELLERS AND IMPORTERS,
No. 810 WALNUT STREET.

A LOXDOI^ :

SAMPSON LOW, MARSTON, SEARLE & RIVINGTON,
CROWN BUILDINGS, 188 FLEET STREET.

1885.




&-



^'^y



5



Copyright by

CHAKLES THOMAS DAVIS,
1884.



COPl'RIGHT BY

HENRY CAREY BAIRD & CO.

1884.




^.W^



COLLINS, PRINTER.



PREFACE



Considering the importance of the leather industry, it seems
strange that up to the present time it should in technical
literature have been so much neglected.

There is not in England nor is there in America a single
current book broadly treating all the branches of this subject,
and the object of the present volume is fully to explain the
details of manufacturing all kinds of leather in common use,
and produced from hides and skins by the agency of the usual
tanning substances.

The author has not been satisfied to make use of the matter
found in obsolete books, but has preferred to present a view of
the state of the art as it to-day exists in the United States.

The tools, machines, and in fact nearly all the mechanical
appliances illustrated in the present treatise are of American
origin, and in common use in the numerous tanneries and
leather-finishing shops of the country.

The collection, compilation, and collation of the vast amount
of technical and detailed information attainable relating to the
various processes, and to the construction of the numerous ma-
chines herein described, have required almost herculean labor.
But the work has been greatly aided by many of the leading
tanners and curriers of the United States, who have not only
placed at the author's disposal every opportunity for personal
observation, but have promptly and courteously responded to



IV PREFACE.

his letters when containing requests for information. It is
doubtful if such facilities as have been extended to him
would be granted to a like professional writer on technical
subjects in any other country in tlje world.

The enormous development of American leather manufactur-
ing industries is a source of much congratulation. There are of
course in this manufacture, as in all others, times of depression,
but the natural facilities for obtaining the raw material, the
great ingenuity of our people, and the steady increase in the
export demand, added to the large home consumption of leather,
are certain to keep the United States in the position of the
leading leather-producing country of the world.

The invention and employment of a large number of mechan-
ical appliances have done much to stimulate and cheapen leather
production in the times just passed, and those manufacturers
who have clung to the old-fasliioned metliods of tanning and
finishing leather by hand have found their business absorbed
by more enterprising firms.

Sucli results were only natural, and it is therefore in the future
very desirable that those now in the business should keep fully
abreast of the improvements in the art. When a machine or
process has, after fair trial and investigation, proved to be an
improvement upon old methods, it is simply suicidal to a busi-
ness not to employ it. Every new method or contrivance is
not necessarily an improvement: but the success of small
tanners and curriers in the future lies solel}^ in the discrimi-
native adoption of labor-saving machines and time-saving
processes.

It is among those who j)roduce leather on a small scale that
many chemical experiments in depilating, bating, and tanning
could be conducted without serious loss or inconvenience, and
it is urgently recommended that in the future more attention
be given to this subject than it has received in the past. Every



PREFACE. V

process or machine used in leather manufacture that has been
patented in the United States since 1790 to the close of the
year 1883 is mentioned in this work. Ten volumes of the size of
the present one would not have been sufl&cient to describe them
all in full, but a printed copy of any patent issued since the year
1866 will, on receipt of twenty -five cents, be sent by the Com-
missioner of Patents to any address in the postal union. The
patents issued prior to 1866 require to be copied in manuscript,
and are therefore charged for by the United States Government
according to the number of words contained in them. Thus
there is by means of the present volume placed at the disposal
of any person who desires it, an opportunity to become fully
acquainted with every step and improvement in leather manu-
facture made in the United States during nearly a century.

The author desires to acknowledge the assistance which he
has received from Dr. Thomas Antisell, Mr. John P. Chapman,
and Prof. Benjamin S. Hedrick, examiners in the United States
Patent Office, all of whom have most kindly and willingly aided
him in many ways. The numerous and valuable lists of patents
contained in this volume could not have been perfected but for
the facilities which the above-named gentlemen have extended.

Prof. William H. Seaman, assistant examiner, early mani-
fested his interest in the work, and his suggestions from the
first have proved valuable.

Col. Weston Flint, and his assistants in the scientific library
of the United States Patent Office, have also greatly aided the
author in his researches, and to them also he desires to ac-
knowledge his indebtedness.

To the enterprising publishers of this volume much credit is
due. They have most kindly responded to every suggestion of
the author, and have cooperated with him in every particular,
sparing neither time, labor, nor expense.



VI PREFACE,

The chernistr}'- relating to leather, skin, and tannins has been
compiled from the best German and French authorities, and due
credit is given for all such matter in the proper places in the
volume.

It is earnestl}^ hoped by the undersigned that his long labors
will not prove unfruitful, and that many persons will be bene-
fited by his work.

CHARLES T. DAVIS. <

1114 Pennsylvania Avenue,

Washington, D. C, Nov. 22, 1884.



CONTENTS.



PART I.
CHAPTER I.

HJDES AND SKINS — THE VARIETIES OF HIDES AND SKINS USED FOR
LEATHER — REMOVING HIDES AND SKINS FROM ANIMALS — SELECTING
HIDES AND SKINS — FRAUDULENTLY INCREASING THE WEIGHT OF
HIDES — PRESERVING HIDES — LIST OF AMERICAN PATENTS FOR PRE-
SERVING HIDES-^COMMERCIAL CLASSIFICATION OP HIDES.

PAGE

Historical facts relating to the use of Hides and Skins of Animals . 33

Early facts in regard to flocks and herds as given in the Old Testament . 34

Cattle breeding in the United States ; the Empii-e of Nature divided
into three Kingdoms — Mineral, Vegetable, and Animal ; their con-
nection with the Leather Industry ; the Mineral Kingdom ; the Vege-
table Kingdom . . . . . . . . . . . 35

The Animal Kingdom ; the Skins which are applicable to the Manu-
facture of l^eather ; Historical facts regarding the Manufacture of
Leather 86

Surmises as to the manner of the origin of the Art of Tanning . . 37

Varieties of Hides and Skins used for Leather ; Classification of Tanned
Leather and of the parts of Hides ; Hides, Kips .... 38

Skins ; Mammiferous Animals, and their application to the wants of Man ;
the Common Ox — its Flesh, Horns, Cartilages, Bone, Hair, etc. ;
Glue ; Effect of the improvement of the Breed of Cattle on their Hides 39

Hides from UnimproAred Breeds preferred by the Tanner ; Cattle-Skins
the chief source of supply for Tanneries ; whence procured and the
Characteristics of those from the Various Countries . . . .40

Heavy Hides and Medium Weight Hides, Calf-Skins, Sheep- Skins,
I^amb-Skins whence derived, and Varieties of Leather which they
produce . . . . . . . . . . . .41

Sheep and Lamb- Skins, the next in impor'_tance to Ox Hides as sources
of Leather ; the value of a Breed of Sheep for the Tanner in inverse
proportion to its value as Wool ; Some of the uses of Sheep and Lamb
Skins; Goat Skins .......... 42

Horse Hides, and the Skins of the Ass, Zebra, Quagga, etc. ; Horse
Leather and the importance of this Industry ; Seal- Skins . . .43



Vm CONTENTS.

VAGE

Hog-Skins, Dog-Skins, Porpoise- Skins, Hippopotamus, and Elephant
Hides ; Alligator Skins, the Alligator Leather Industry in the United
States ; Characteristics and Uses of Alligator Leather ... 44

Kangaroo-Skins and the Leathers which they produce ; Buffalo Hides,
Deer-Skins, Shark and Rhinoceros Skins, AValrus Hides ; Removing
Hides and Skins from Animals ........ 45

Directions urgently recommended in Flaying Hides and Skins ; Import-
ance of these dii'ections ......... 46

Selecting Hides and Skins; the Hides of Oxen, Bulls, and Cows; the
Hides of Animals dying of disease ; Criteria for guiding the purchaser
in distinguishing the quality of Hides and Skins . . . .47

Hides of Animals dying from contagious diseases should be rejected or
handled with great care ; danger of handling such Hides ; Poisoning
by Bacterium, AntTirax producing Malignant Carbuncles : Disinfecting
I'anneries and other places where Skins are stored ; Importance of
thorough Cleansing of the Store-room ...... 48

Fraudulently increasing the Weight of Hides by the employment of Sul-
phuric Acid ; Tests for the Detection of this Fraud ; Preserving Hides ;
Mode of Salting ; Delane's Method the one generally employed . 49

Quantity of Salt required; Glauber's Salt for Salting Hides; Other
Materials for Preserving Hides ; Moret's Composition for Impregnating
Hides and Skins and Preserving them so as to be capable of being
unhaired by a simple immersion in water ...... 50

The Preparation and Application of Moret's Composition . . .51

Advantages claimed for Moret's Composition ; Rock's Liquid for Curing
Hides 52

Sabath6 and Jourdan's Process ; Napier's Process, Sacc's Process,
Wickersheimer's Process ......... 53

List of all Patents issued by the Government of the United States of
America for Preserving Hides from 1790 to 1883 inclusive ; Commercial
Classification of Hides ; Dry Flint ; Dry Salted ; Green Hides . . 54

Green Salted Hides ; Part Cured Hides ; Damaged Hides ; Glue Stock ;
Branded Hides ; etc. . . . . . . . . .55



CHAPTER IL

SYNOPSIS OF THE HISTORY OF TANNING — COMMERCIAL VARIETIES OF

LEATHER.

Synopsis of the History of Tanning ; Conditions upon which an Art must
rest in order to improve ; Facts in reference to the history of Leather
derived from the Old Testament ....... 5C

Colored Leather described by Ezekiel as early as 593 B. C. as in use
by Babylonians, Chaldeans, Pecods, Shoas, Koas, and all the Assyrians ;
Testimony of Herodotus in regard to the use of Leather; Early use



CONTENTS. IX

PAGE

of Leather by the Greeks, Phoenicians, Germans, and Britons ; Testi-
mony of Homer and Hesiod ........ 57

Early expressions regarding the use of Leather ; the legend of St. Crispin ;
the names of the early discoverers and improvers of the Processes of
Tanning Leather ; Discoveries of MacBride (1768), Seguin (1 795), and
Banks (1801); MacBride's Process of Raising by Sulphuric Acid;
Seguin's Method by which Hides and Skins were Tanned in a shorter
time, and Banks's discovery of the Tanning Property of Terra Japonica

(Catechu) 58

The English discovery of the Art of Varnishing Leather ; the introduction
of the art of preparing AVater-Proof Leather by Ballamy, Von Hilde-
brandt, Edward, and others ; Little done by science in regard to the
Improvement of the Art of Tanning ; Great improvements made in
Apparatus, especially in the United States ..... 59

Skill not force, Chemical Knowledge not steam power, which in the
future must cheapen and accelerate the Process of Tanning ; our in-
ventors must aim to be good Chemists, as well as good Mechanics ;
Room for inquiry after Tanning Materials and as to the Hide itself
and its Structure .... ...... 60

The System of Tanning or Tawing by means of Chromium Compounds
by Dr. Heinzerling in Germany ....... 61

The claims of Dr. Heinzerling as to the meritorious and original features
of his Process ; Experiments of David Kircaldy, London, on Bark-
Tanned and Chrome Leather ; Advantages which seem to be offered
by the Chrome Process . . . . . . . • .62

Localities in which Dr. Heinzerling's Process, is in use ; Not yet full}'
passed critical stages of practical experiment ; Commercial varieties
of Leather ; Characteristic properties of Leather ; Leather Chemic-
ally considered .......... 63

Tawing and the class of Skins to which it is applied ; Tawing practised
by the Romans ; Introduced into Hungary in the 1 2th Century ;
Chamois Dressing invented in Hungary ; the Hungarians celebrated
in early times for their White Leather ; French and Dane's Leather
made from Lamb and Goat- Skins for the manufacture of Kid Gloves . 64
Red or Bark Tanning the oldest Method of Tanning ; Leather similar to
Morocco and Cordovan made by the Ancient Orientals ; Persian and
Babylonish Leather ; the art of making Leather brought from Asia
into Europe ; the Turks, Russians, and Hungarians, the most cele-
brated Tanners in the first centuries of the Christian era ; Cordovan,
Morocco, Shagreen, and Russia Leather ...... 65

The Morocco Leather Industry in the United States ; Decline of the
Morocco and Chamois Leather Industries in Russia; the Tanning-
Industry in Russia . . . . . . . . . .66

Shagreen and Russia Leather . . . . . . . .67



X CONTENTS.



Hungarian Leather ; Parchment ; Artificial Parchment ... 68

The use of Parchment, and where most hirgely produced ; Alum Leather ;

JBazil ; BufF Leather ; Chamois, Shammy, or Shamoy Leather ;

Enamelled Leather . . . . . . . . . .69

Enamelled Leather first manufactured in the United States in Newark, N.

J. ; Fair Leather ; Juncten ; Japanned, Patent and varnished Leathers

first made in the United States at Newark, N. J.; Oil Leather;

Roan; Russet; Saffian Leather ; Mogador Leather ; Skiver . . 70
Split Leather ; Wash Leather ; Whang ; White Leather or Tawed

Leather; List of names applied to Leathers in Commerce . . 71

Artificial Leather and its uses ; Vegetable Leather . . . .7?

Artificial Leather produced in Boston, Mass.; Importance of the Leather

Industry in the United States ........ 73

^ CHAPTER IIL

STATISTICS OF THE TANNING INTERESTS IN THE UNITED STATES.

Statement of the number of Tanneries in the United States ; Capital ;
Hemlock and Oak Bark used ; Hides and Skins Tanned and the
total value of products for the year 1880 . ... . . .74

The leading States engaged in this Industry . . . . . .76

Increase of Tanneries in Virginia, Tennessee, and other Southern States ;
Exports and Imports of Leather ; the Leather Industry in Italy . 77

The Leather Industry of the United States rivals those of England,
Germany, and Austria, and our exports should be largely increased ;
Objections of English Tanners to our Leather ..... 78

Imports and Exports of Hides, Skins, Bark for Tanning, Cutch, and
Gambir, Tallow, Fish Oils, etc., into and out of the United States for
the twelve months ending June 30, 1882, and June 30, 1883, respec-
tively ; Number of Leather Currying Establishments in the United
States and their product in 1880 ; Importance of this Industry in
Massachusetts . . . . . . . . . . .79

Table of the Leather Currying industry of the twelve leading States,
representing nine-tenths of the whole business ..... 80

CHAPTER IV.

EXAMINATION OE LEATHERS.

Importance of the determination of the value and quality of Leather by
chemico-technical examination; Marquis's Method — 1. Determination
of fat and resin . . . . . . . . . .81

2. Determination of Lime in Leather. 3. Determination of the Tan-
ning constituents : Method proposed by Heinzerling ; Determination
of AVater ; Percentage of Ash ; Importance of determining the amount
of Lime in Leather . . . . . . . . . . 82



• CONTENTS. XI

PAGE

Percentage of Fat . . . . . . . . . .83

To determine the Sebaoie Acid ; Determination of Nitrogen ; Plan pro-
posed by Muntz; Barrentrapp-Will Method ; Cori'in, formulae of Reimer 84

Tanning Substance. 1. Tannic Acid ; Defects of Marquis's Method for
determining Tannic Acid ; Mittenzweig's Method. 2. Mineral Con-
stituents ; Determination of Mineral Materials in Mineral Tanned
Leathers of Knapp and Heinzerling ; Examination of the cutting sur-
face of leather, as a criterion ; Behavior of Tanned Leather toward
boiling water as a test . . . . . . . . " . 85

Determination of means used to increase the weight of Leather ; Detec-
tion of Adulterations, such as Glucose, added for this purpose ; Physi-
cal methods of testing Leather ........ 86

I. Change in volume and ability for resisting water ; Table of Dr. Hein-
zerling in regard to the comparative resisting qualities of Tanned
Leather and Heinzerling' s Mineral Tanned Leather . . . .87

Results shown by the Table ; IL Testing the strength of Leather ;

AVeiner's Apparatus . ... . . . . . 89>'

Tables showing the strength of a Skin in different places ... 91



PART II.
CHAPTER Y

ANIMAL SKIN.



The Raw Products with which the Tanner has to deal — 1. Hides and
Skins. 2. Tanning Materials ; the construction of Animal Skin ; the
Ejjidermis and its Composition ........ 93

The Epidermis does not combine with Tannin, and is, therefore, useless
to the Tanner ; the Corium or Leather Skin ; the Quality of the
Leather dependent upon the thickness, flexibility, and strength of the
Corium ; Coriin ; Illustration showing an enlarged Transverse Section
of the Skin 94

Chemical Process in the production of Glue ; Skin slowly and completely
dried in the air can be kept for a long time ; Decomposition of Moist
Skins ; Preservation of Skins with Salt, . or Immersed in Strong
Brine ; the Chemical and Morphological Constitution of Skins as shown
by RoUet and Reimer ......... 96

Modes of Preparing Coriin ; to obtain perfectly pure Coriin free from
an admixture of Cell Elements . . . . . . .97

Behavior of Coriin toward different Substances ; Liming contliuied too
long gives poor weight ; Composition of Coriin ; Connective Tissue
Substance and the Intercellular Substance, the difference between . 98



Xll CONTENTS.

PAGE

To prepare Connective Tissue Substance ; Behavior of Connective Tis-
sue Substance towards various other Substances .... 99
The Swelling Property of Skin Fibre 100

CHAPTER VT.

VEGETABLE TANNING MATERIALS.

Section I. Tannix or Tannic Acid ; Tannin or Tannic Acid ;
Great variety of Plants in which Tannic Acid occurs . . . .100

The different varieties of Tannin, their Chemical and Physical behavior,
and whence derived .......... 101

Classification of Tannic Acids by E. Wagner into physiological and
pathological Tannic Acids ; -whence these Tannic Acids are derived ;
Wagner's views on the Subject of Leather Tanned with the respective
Tannic Acids ; our knowledge of the different Tannic Acids still in-
complete ; Principal obstacles to a determination of the Nature of
Tannic Acids 102

Gallotannic Acid — Tannin of the Xut-gall ; Discovered by Lewis in the
Eighteenth Century; Pelouze's Process for its Examination; Appa-
ratus of Robiquet and Boutron . . . . . . . . lOo

Process of Mohr for the Exhaustion of Gall-nuts . . . . .104

Appearance and Qualities of the Tannin ; Domine's Process for the ex-
haustion of Gall-nuts ; Separation of the Tannic Acid by the Aqueous
Solutions of Sulphuric and Hydrochloric Acids, etc. ; Melting and de-
composition of Tannin ......... lOS

Behavior of Tannin under various conditions ; Tannin considered by

Sti'ecker a Glucoside . . . . . . . , .106

More recent Experiments prove Tannin not to be a Glucoside ; Experi-
ments of Rochleder and Kawalier ; Liebig on the Transformation of
Tannin into Gallic Acid by means of Potash and thence into Carbonic
and Pyrogallic Acids ; Behavior of Tannin toward various Substances 107

Jmpure Tannin Substances modify themselves when kept in contact with
the Air ; Constituticni of Gallotannic Acid ; Experiments of Strecker
and Schriff ; Conclusions of SchrifF; Schriff's formula of Tannin . 108

The new formula of Tannin confirmed ; Tannomelanic Acid ; how ob-
tained ; Tannopinic Acid . . . . . . . . .109

Tannoxylic or Ptufitannic Acid ; Quercotannic Acid ; Properties and
Behavior of Quercotannic Acid. . . . . . . .110

Quercus Red ; Quercus Bitter or Quercin . . . . . .111

Querphlobaphene ; Phloroglucin ; Protocatechuic Acid ; Pyrocatechin ;
the property in Tannic Acid of forming insoluble combinations with
Alkaline Salt ; loss of Tannic Acid in using Hard Water ; Fermenta-
tion of Tannic Acid by Fungi - and P'erments ; Filtering of Water
through exhausted Tan ; Researches of Sclmlze in regard to the Tan-
nic Acid yielded by Oaks of different ages . . . . .112



CONTENTS. Xlll

PAGK

Tannic Acid generally present in the Roots, Barks, and Branches of
Trees ; Tannic Acid a Brimary product of Vegetable Life ; Action of
the different Tannic Acids toward the Corium or Leather Skin ; Tan-
nic Acid which when heated forms Byrogallic Acid, furnishes
Leather less capable of resisting Water than Tannic Acid yielding
Pyrocatechin ; Influence of Extractive Substances upon the value of a
Tannic Acid; Influence of Resins, Pectine Substances, etc. . .113

Spxtion IL Vegetable Tanning Materials .... 113

Rutea ; Kino ; African Kino, Malabar or East Indian Kino ; Kino very
rich in Tannic Acid ; Garabier, its percentage of Tannin high ; Cate-
chu or Terra Japonica ; its Constituents, Qualities, and Adulterations;
the Leather produced from Catechu ; Gall-nuts — the richest in Tan-
ning of all Tanning materials, their formation and qualities . .114

Green Galls ; European Galls ; Chinese Gall-nuts ; the countries in
which Gall-nuts are produced ; Rove or Bassora Gall-nut . . .115

Sumach ; different varieties of Sumach found in Commerce — Sicilian,
Italian, Spanish, Tyrol, French, and American Sumachs . . .116

Swedish Sumach ; the Tannic Acid contained in the Sicilian Sumach
according to Stenhouse identical with Gallotannic Acid ; Tannic Acid
of Old Sumach ; Leather prepared with Sumach possesses but little
capacity of resisting Water ; Valonia ; Qualities of Leather prepared
with Valonia ; Divi-divi ; Qualities of Leathers Tanned with divi-divi ;
Tannic Acid of divi-divi ; Myrobalans . . . . . .117

Bublah ; Logwood ; Fustic ; Weld ; Larch Bark ; Fir Bark ; Hemlock

Bark; Qualities of Hemlock Bark . . . . . . .118

American Hemlock Extract; Oak Barks; Walnut Bark; Lombardy
Poplar Bark; Elm Bark 119

Horse-chestnut Bark ; jEsculotannic Acid ; qualities, constitution, and
behavior of ^li^sculotannic Acid ; Horse-chestnut Extract ; AVillow
Bark 120

Alder Bark ; Beach Bark ; Protaceae Barks ; Snouba Bark ; Scorza
Rosa; Ratanhy Root 121

Avens Root ; Tormentil Root ; Sassafras Root ; Live Oak Wood ; Que-
bracho ; Mimosa . . . . . . . . . . 122

Table showing the percentage of Tannin contained In the various Tanning-
materials determined according to different methods . . . .123

Results of more recent examinations of various substances containing
Tannin, according to Fraas . . . . . . . .124

Tanning materials used in most countries only such as are there produced
in great abundance ; the Tanning materials used in principal countries ;
Practical experiments show that there is a considerable difference in
the quiintity of the various Tannins absorbed by the Skin; Table of
the quantities of Tannin required, according to Anthon, for the con-
version of each one pound of Skin into Leather .... 125



XIV CONTENTS.

PAGE

Table of Experiments ; Experiments by Kester showing the increased
weight of Hides after Tanning ........ 126

Tables of Experiments of Prof. Miintz and Dr. Schon regarding the ab-
sorption of different Tannins by the Skin, and of the removal of resi-
nous extractive substances in Leather Tanned with different Tannins ;



Online LibraryCharles Thomas DavisThe manufacture of leather: being a description of all of the processes for the tanning, tawing, currying, finishing → online text (page 1 of 70)