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Full text of "A practical treatise on the manufacture of vinegar and acetates, cider, and fruit-wines; preservation of fruits and vegetables by canning and evaporation .."

I 








A PRACTICAL TREATISE 



ON THE 



MANUFACTURE OF VINEGAR AND ACETATES, 
CIDER, AND FRUIT-WINES. 



A PRACTICAL TREATISE 



ON 




PRESERVATION OF FRUITS AND VEGETABLES BY 
CANNING AND EVAPORATION; 



PREPARATION OF FRUIT-BUTTERS, JELLIES, MARMALADES, 
CATCHUPS, PICKLES, MUSTARDS, ETC. 



EDITED FROM VARIOUS SOURCES, 



BY 

WILLIAM T. BRANOT, 

ONE OF THE EDITORS OF "THE TECHNO-CHEMICAL EECEIPT BOOK." 



ILLUSTRATED BY SEVENTY-NINE ENGRAVINGS. 



PHILADELPHIA : 
HENRY CAREY BAIRD & CO., 

INDUSTRIAL PUBLISHERS, BOOKSELLERS, AND IMPORTERS, 
810 WALNUT STREET. 

LONDON : 

SAMPSON LOW, MARSTON, SEARLE & RIVINGTON, LIMITED, 
ST. DUNSTAN'S HOUSE, FETTER LANE, FLEET STREET, E. c. 

1890. 




71 



COPYRIGHT BY 
HENRY CAREY BAIRD & CO. 

1889. 



PRINTED AT THB COLLINS PRINTING HOUSE, 

705 Jayne Street, 
PHILADELPHIA, U. S. A. 



0* 

VII7ERSITT 




PREFACE. 



IT is quite unnecessary here to enlarge upon the prominence 
and the commercial value of the products of the various branches 
of industry treated of in this volume, since they are indispensable 
requisites as well in domestic economy as in the arts. But not- 
withstanding the great importance of .these subjects, little reliable 
information in regard to them is found in our technical literature, 
and that little is so widely scattered as to make it almost inac- 
cessible to most manufacturers. 

Of all the branches of industry based upon chemical processes, 
the manufacture of vinegar has made the least progress, and con- 
sequently disturbances and large losses of material are here of 
much more frequent occurrence than in other fermenting indus- 
tries which are carried on in accordance with established rules, 
whose correctness has been ascertained by many experiments. 

With few exceptions there are no works in the English lan- 
guage in which an attempt has been made to establish the manu- 
facture of vinegar upon a rational basis, and in accordance with 
the laws of nature as regards the chemical as well as the physi- 
cal processes. To attain this object as nearly as possible has 
been the aim in the preparation of the portion of this volume 
relating to vinegar. Since the physical processes, especially the 
exact maintenance of determined temperatures and the production 



yi PREFACE. 

of a change of air corresponding to the chemical processes, play 
an important role in the manufacture of vinegar, the section re- 
lating to this subject has been very fully treated. 

To the manufacture of wine-vinegar a space corresponding to 
the importance of the subject has been devoted. Wine-vinegar 
is undoubtedly the most valuable product of the vinegar industry, 
and its fabrication might be made specially advantageous in this 
country, since in California and other States a vast amount of 
material could thus be profitably utilized, which otherwise would 
go to waste. On account of its great interest considerable space 
has been devoted to the manufacture of acetic acid from wood, 
and of acetates, especially those which are used for technical 
purposes. 

As regards the manufacture of cider and fruit-wines, the 
preservation of fruit, etc., much time and care have been devoted 
to the gathering of information from all available and widely- 
scattered sources in order to do justice to the great and constantly 
growing fruit industry of this country. Special attention has 
been paid to evaporation, since this process is likely to supersede 
all other modes of drying fruit. 

The volume is divided into three parts, upon each of which a 
few observations are offered. 

Part I. treats of the Manufacture of Vinegar. It is chiefly 
based upon the German works, Die Schnell-Essig Fabrication 
und die Fabrication von Weine&dg, by Dr. Josef Bersch, and 
Lehrbuch der Essigfabrikation, by Dr. Paul Bronner. Both are 
works of acknowledged authority, in which the authors have 
brought together the results of their experience of many years. 



PREFACE. VI 1 

Part II. contains the Manufacture of Cider and Fruit-wines, 
and Part III. Canning and Evaporating of Fruit, etc. For in- 
formation on these subjects we are indebted to the French work, 
Culture du Pommier d Cidre, Fabrication du Cidre, etc., by Jules 
Nanot, and to the German works, Die Hebung der Obstverwerth- 
ung und des Obstbaues, by Heinrich Semler, and Die Obstwein- 
kunde, by Dr. N. Graeger. Wherever required, the information 
derived from the above works has been supplemented by Amer- 
ican processes. 

The editor also acknowledges his indebtedness to numerous 
American and English authors for valuable information, due 
credit for which has been given whenever possible. 

A copious table of contents as well as a very full index will 
render reference to any subject in the book prompt and easy, 
and the whole treatise is submitted to the public with a feeling 
of confidence as to its value and usefulness. 

WILLIAM T. BEANNT. 



PHILADELPHIA, Sept. 26, 1889. 




CONTENTS. 



PART I. 

THE MANUFACTURE OF VINEGAR. 
CHAPTER I. 

INTRODUCTION. 

PAGE 

Ordinary vinegar, what it is ; The discovery of vinegar ; Use of vinegar 
as a medicine by Hippocrates ; Early knowledge of the property of 
vinegar of dissolving calcareous earths ; The dissolving of large pearls 
in vinegar by Cleopatra . . . . . . . . .17 

The use of vinegar by Hannibal for dissolving rocks ; No early definite 
knowledge of the cause of the production of vinegar; The process 
of increasing the strength of wine-vinegar made known by Gerber in 
the eighth century; Other historical data regarding vinegar; The 
first preparation of acetic acid in a pure state and the discovery of 
the property of very strong acetic acid to crystallize at a low temper- 
ature ; Historical data regarding the formation of an acid body in the 
dry distillation of wood ; Determination of the exact chemical consti- 
tution of acetic acid by Berzelius and that of alcohol by Saussure ; 
Historical data relating to the generation of acetic acid . . .18 
The introduction of the quick process of manufacturing vinegar, in 1823, 
by Schiitzenbach ; A method of manufacturing vinegar from wine 
made known by Boerhaave ; ScMitzenbach's original plan of working 
still in use in some localities ; Necessity of progress in the manufac- 
ture of vinegar by the quick process; The constantly increasing diffi- 
culties in the manufacture of vinegar from alcohol . . . .19 

Great purity of the acetic acid at present produced from wood ; Use of 
"vinegar essence" for pickling, etc. ; Difference between the acetic 
acid produced from wood and vinegar prepared from various sub- 
stances ,....... 20 

Principal defects in manufacturing vinegar by the quick process in general 
use ... 21 



X CONTENTS. 

CHAPTER II. 

THEORY OF THE FORMATION OF VINEGAR. 

PAGE 

Explanation of the chemical processes by which acetic acid in large 
quantities is formed ......... 21 

Liebig's theory of the formation of vinegar ; The formation of vinegar 
due to a chemico-physiological process ...... 22 

Pasteur's theory of the formation of vinegar; Difference between 
Pasteur's and Nageli's views; Nomenclature of organisms producing 
fermentation ; The vinegar or acetous ferment ; Origin of the acetic 
acid formed in alcoholic fermentation ...... 23 

Occurrence of acetic acid in nature ; Formation of acetic acid by chemi- 
cal processes ; Formation of acetic acid by the action of very finely 
divided platinum upon alcohol, illustrated ..... 24 

Development of " mother of vinegar" ...... 25 

Pasteur's examination of the relations of the mother of vinegar to the 
formation of vinegar; The botanical nature of the organisms causing 
the formation of vinegar ; Disease-causing bacteria ... 26 

What constitutes the entire art of the manufacture of vinegar . . 27 

CHAPTER III. 

THE VINEGAR FERMENT AND ITS CONDITIONS OF LIFE. 

The vinegar ferment, its origin and distribution ; Fluid especially 
adapted for its nourishment 27 

Experiment showing the conversion of wine into vinegar by the vinegar 
ferment, with illustration ........ 28 

Duration of life of the vinegar ferment ; Difference between the living 
and dead ferment as seen under the microscope ; Requirements of 
the vinegar ferment for its augmentation . . . . .29 

Results of the withdrawal of oxygen from the vinegar ferment ; Ex- 
periment showing the great rapidity of the augmentation of the 
vinegar bacteria ; Nourishing conditions of the vinegar ferment . 30 

Factors required for the settlement of the vinegar bacteria upon a fluid 
and for their vigorous augmentation ; Composition of the nourishing 
fluid ; A large content of alcohol in the nourishing fluid detrimental 
to the vegetation of the vinegar ferment ; Experiment showing that 
the vinegar ferment cannot live in dilute alcohol alone . . .31 

The preparation of a fluid containing all the substances essential to the 
nourishment of the ferment ; Sensitiveness of the vinegar ferment to 
sudden changes in the composition of the fluids upon which it lives ; 
The process of nourishment of the vinegar ferment . . .32 

Supply of air required by the vinegar ferment ; Limits of temperature 
at which the augmentation of the ferment and its vinegar-forming 



CONTENTS. XI 

PAGE 

activity are greatest ; Action of the ferment when exposed to high 

and low temperatures . . . . . . . . .33 

Difficulty of rearing the vinegar ferment upon a cold fluid ; Reason why 
acetous degeneration is not known in cold wine cellars ; Reasons for 
the ready occurrence of disturbances in the formation of vinegar at a 
high temperature ; Mother of vinegar ; Origin of the term . . 34 

Occurrence, appearance, and growth of mother of vinegar ; Different 
opinions as to the nature of mother of vinegar . . . .35 

Composition of the mother of vinegar according to Mulder and R. D. 
Thomson ; Substances which participate in the formation of mother 
of vinegar, illustrated by an experiment ; How the formation of 
mother of vinegar can be successfully attained . . . ,36 

General occurrence of mother of vinegar in young wine ; Erroneous 
opinion as to the part mother of vinegar takes in the formation of 
vinegar; Summary of the theoretical conditions of the formation of 
vinegar of importance to the manufacturer . . . . .37 

CHAPTER IV. 

PRODUCTS OF ACETOUS FERMENTATION. 

The regular augmentation of the ferment the main point of the entire 
fabrication ; Occurrence of loss of alcohol in the fabrication . . 38 

Bodies, besides alcohol and carbonic acid, formed in the vinous fermen- 
tation ; Characteristic properties imparted to alcohol by fusel oils ; 
Aromatic substances which reach the vinegar through the conversion 
of fusel oils; Acetic aldehyde or acetaldehyde . . . .39 

Preparation and constitution of pure aldehyde ; Acetal ; Preparation 
of acetal 40 

Composition and nature of pure acetal . . . . . .41 

Acetic acid ; Glacial acetic acid ; Properties of acetic acid ; Peculiar 
behavior of mixtures of acetic acid and water in regard to their 
specific gravity 42 

Difference in the determinations of specific gravities of acetic acid with 
a varying content of water ; Uses of highly concentrated acetic acid ; 
Composition of acetic acid ........ 43 

Theoretical yields of acetic acid ; Theoretical and practical yields, what 
they are ; Mariner of calculating the theoretical yield of acetic acid 
from alcohol ........... 44 

Quantity of oxygen consumed in the formation of vinegar ... 45 

Quantity of alcohol which can be daily converted into vinegar by a vine- 
gar generator ; Calculation of the quantity of heat liberated by the 
conversion of alcohol into acetic acid ; What the practical manufac- 
turer can learn from theoretical explanations 46 



Xll CONTENTS. 

PAGE 

Proof that the generators now in use are deficient ; The optimum tem- 
perature, what is meant by it ; Loss of alcohol and acetic acid by 
evaporation and its reduction to a minimum . . . . .47 

Conditions on which the most advantageous manner of working depends; 
Yields of acetic acid obtained in practice ; Unavoidable losses in a 
vinegar factory ; Defectiveness of the processes in general use and 
the necessity for reformation . . . . . . . .48 

Comparison of a vinegar generator to a furnace . . . . .49 

CHAPTER Y. 

METHODS OF FABRICATION OF VINEGAR. 

Reasons for not commencing the description of the various methods of 
fabrication of vinegar with the oldest and most simple method known, 
viz., the fabrication of vinegar from wine ; Why we can speak of 
grain and malt vinegars ......... 50 

Alcohol the ultimate material for the fabrication of vinegar ; The slow 
and quick processes of fabrication ; Modifications in the old process 
according to the materials used . . . . . . .51 

Difference in the properties of vinegar derived from various sources . 52 

CHAPTER VI. 

QUICK PROCESS OF FABRICATION OF VINEGAR. 

Invention of Schutzenbach's and analagous processes ; On what the 
principle involved depends 52 

Appropriateness of the term " quick process;" Comparison of the 
generator or "graduator" to a furnace ; Difficulty of conveying the 
requisite amount of air to the generator ...... 53 

Arrangement of the generators ; The best form of the generator, with 
illustration 54 

Variation in the dimensions of the generators ; Disadvantages of small 
and of large generators ........ 55 

Erroneous opinions in regard to the manufacture of strong vinegar; Di- 
mensions of the most suitable generators ; Cover of the generator, 
with illustration 56 

Disadvantage of a number of obliquely bored apertures below the false 
bottom, with illustration .... 57 

Different forms of generator ; Self-acting discharge arrangement, with 
illustration . . . . . . . . . . .58 

Disadvantage of the self-acting discharge arrangement and substitute 
for it ; Arrangement of the disk or false bottom of the generator, 
with illustration . 59 



CONTENTS. xiii 

PAGE 

Arrangement for regulating the influx of air from below, with illustra- 
tion 60 

Modification of the disk, with illustration ; The tilting trough, with 
illustrations . . . . . . . . . . .61 

Arrangement and manner of working of the tilting trough ; The sparger 
described and illustrated . . . . . . . .62 

The principal requisite of the correct working of the sparger, with illus- 
tration ; Difficulties overcome by the use of the sparger ... 64 

A thermometer an indispensable adjunct to a generator; Manner of 
locating the thermometer ; Filling of the generators ; Materials used 
for filling the generators ; Advantages of beechwood shavings . 65 

Preparation of beech shavings ; Volume represented by a shaving in a 
rolled state ; Space required for each shaving ; Size of the space to 
be filled with shavings in a generator ; Number of shavings required 
to fill this space ; Surface of shavings active in the formation of vine- 
gar ; Steaming of the shavings ' 66 

Drying of the shavings ; Swelling of the shavings . . . .67 

Manner of placing the shavings in the generators ; Advantage of hav- 
ing all the generators of the same size 68 

CHAPTER VII. 

ARRANGEMENT OF A VINEGAR FACTORY. 

Unsuitableness of the arrangement of the manufacturing rooms formerly 
customary ; The principal requisites for a suitable arrangement of the 
factory 68 

Arrangement of the walls, windows, doors, and floor of the factory ; 
Height of the workroom : Heating of the workroom ; The best 
arrangement where stoves are used ; Heating apparatus for large 
factories described and illustrated . . . . . . .69 

Necessity for thermometers in the workroom ; The maximum electrical 
thermometer described and illustrated ...... 71 

The minimum electrical thermometer ; Location of the reservoirs in 
a factory arranged according to the automatic system . . .72 

CHAPTER VIII. 

ARTIFICIAL VENTILATION OF THE VINEGAR GENERATORS. 

The English process of sucking a current of air from above to below 
through every generator, with illustrations ; Incorrectness of this * 
process . 73 

The principal reason advanced for the use of a current of air from above 
to below ... 74 



xi v CONTENTS. 

PAGE 

Schulze's ventilating apparatus, with illustrations; Description of 

Sehulze's generator .75 

Objections to Schul/e's apparatus .... 76 

Generators with constant ventilation and condensation ; The object of 

special ventilating contrivances ; Ventilating apparatus according to 

Bersch, described and illustrated ..... .77 

Condensing apparatus, described and illustrated ... .78 

Proposed method of regaining the vapors ; Objection to this method . 80 

CHAPTER IX. 

AUTOMATIC VINEGAR APPARATUS. 

The principal work which has to be performed in a vinegar factory . 80 
Disadvantages of pouring at stated intervals the alcoholic fluid into the 
generators ........... 81 

Advantages to be derived from the use of simple automatic contrivances ; 
Division of continuously working apparatus into two principal sys- 
tems ; Continuously working apparatus the terrace system . . 82 
A factory arranged according to the terrace system described and illus- 
trated 83 

Objections to the terrace system 84 

Advantages of the group system ; Mode of distributing the alcoholic 

liquid into each generator in the terrace system . ... .85 
Periodically working apparatus the three-group system ; Modification 

of the tilting trough, described and illustrated 87 

The siphon barrel, described and illustrated 88 

The bell-siphon, described and illustrated 89 

Example for calculating the space required beneath the lath-bottom of 
the generator for the reception of the fluid ; Arrangement of a vinegar 
factory working according to the automatic principle ... 90 
Manner of arranging the generators in groups ; Height of the actual 
work-room ; Location of the reservoir and of the collecting vessels ; 
Description of a periodically working establishment with 24 generators 91 
Manner of working in such an establishment ..... 93 
Material for metallic vessels used in the factory ; Location of the pump ; 
Advantage of heating the alcoholic liquid before its introduction into 
the generators ; Apparatus for heating the alcoholic liquid described 
and illustrated ....... 94 

CHAPTER X. 

OPERATIONS IN A VINEGAR FACTORY. 

Acidulation of the generators ; Object of acidulation ; Manner of {undu- 
lation ; Quantities of vinegar required for complete acidulation 96 



CONTENTS. xy 

Example illustrating the gradual commencement of the regular fabrica- 
tion ; Accelerated acidulation ; Objection to the ordinary method of 
accidulation ...... 

Percentage of water in the shavings which has to be replaced in the ordi- 
nary method of acidulation by vinegar ; How the removal of water 
from the shavings and its substitution by vinegar are effected; Time 
required for acidulation by the old method ; Loss of vinegar in the 
old method of acidulation ; Advantage and mode of using artificially 
dried shavings ; Time required for acidulation with artificially dried 
shavings ........ 9# 

Induction of the operation with artificially raised vinegar ferment; 
" Pure cultivation" of the vinegar ferment 99 

Preparation and treatment of fluids for the pure cultivation of vinegar 
ferment ........ 10o 

Preparation of nourishing fluid from beer ; Manner of cultivating vine- 
gar ferment . . . . . . . . . . .101 

Abortive cultivation of vinegar ferment with illustrations ; Transfer of 
the pure cultivation of vinegar ferment to the generators . . 102 

Prevention of disturbances which are caused by suddenly changing the 
nourishing fluid of the vinegar ferment 103 



CHAPTER XI. 

PREPARATION OF THE ALCOHOLIC LIQUID. 

Definition of the term "alcoholic liquid;" Reason why a content of 
vinegar in the alcoholic liquid exerts a favorable effect upon the forma- 
tion of vinegar ; Proof that the alcoholic liquid does not require any 
considerable quantity of acetic acid for its conversion into vinegar . 104 

Reasons why it is preferable to gradually increase the content of alcohol 
in the alcoholic liquid instead of at once adding the total amount . 105 

Experiment illlustrating the destruction of acetic acid by (he vinegar 
ferment in the absence of alcohol ; Limit of percentage of acetic acid 
vinegar should have ; Conditions on which the advantageous fabrica- 
tion of high-graded or weak vinegar depends . 

Quantities of beer and of finished vinegar to be added to the alcoholic 
liquid ; Table showing the theoretical yield of acetic acid from alcohol 107 

Reasons why practically less vinegar with a smaller percentage of acetic 
anhydride is obtained ; Table showing the content of alcohol required 
in an alcoholic liquid for the production of vinegar with a certain con- 
tent of acetic acid . . . .*. 

Calculation for finding the number of gallons of water which have tc 
added to alcohol of known strength in order to obtain an alcoholi 
liquid with the desired percentage of alcohol ; Examples of the c 
position of alcoholic liquid .. 



XV111 CONTENTS. 



CHAPTER XIY. 

METHOD OF THE FABRICATION OF VINEGAR IN APPARATUS OF 

SPECIAL CONSTRUCTION. 

PAGE 

Inutility of most inventions for overcoming the frequent disturbances in 
the working of a factory not provided with suitable heating and venti- 
lating arrangements ......... 139 

Singer's vinegar generator, illustrated and described .... 140 

Alirhaelis's rotary vinegar generator ....... 142 

Fabrication of vinegar with the assistance of platinum black, and the 
apparatus used .......... 143 

CHAPTER XV. 

FURTHER TREATMENT OF FRESHLY-PREPARED VINEGAR. 

The odor of freshly- prepared vinegar and on what it depends ; Filling 
of the barrels ; The reciprocal action which takes place between the * 
air and the vinegar . . . . . . . . .144 

Means for improving the odor of vinegar; Manner of drawing off the 

vinegar from the sediment in the barrel, with illustration . .145 

The storing of vinegar . . . . . . . . .146 

Processes which take place during storing . . . . .147 

Advisability of filtering the vinegar; Heating the vinegar; Apparatus 
for heating the vinegar, illustrated and described .... 148 

Filtration of the vinegar ; Filter for vinegar, illustrated and described . 150 
Bag-filter for filtering vinegar under pressure, illustrated and described 151 

Sulphuring of vinegar 152 

Fining of vinegar ; Coloring vinegar .... 153 

Preparation of caramel or burnt sugar .... 154 

CHAPTER XYI. 

PREPARATION OF VINEGAR FROM VARIOUS MATERIALS. 
The formation of diastase ; How vinegar can be prepared from starch . 154 
How the various kinds of vinegar might be designated according to the 

elementary material used ; Reasons why beer-wort does not seem a 

suitable material for vinegar .... 
Use of fermented whisky-mashes for the manufacture of vinegar; 

Manufacture of vinegar from malt and grain ; Combination of "the 

manufacture of compressed yeast with that of vinegar . 156 

The most suitable variety of malt for the preparation of vinegar* The 

constitution of malt .... 

.157 



CONTENTS. XIX 

PAGE 

The theoretical part in mashing; Effective diastase; After-effect of 
the diastase; Calculation of the yield of acetic-acid which can be 
obtained from a given quantity of malt . . . . . .158 

Use of a mixture of malt and-unmalted grain ; Doughing in the ground 
malt; Mashing . . . . . . . . .159 

The percentage of alcohol contained in mashes after fermentation; 

Setting the rnash with yeast; Preparation of compressed yeast . 160 

Treatment of the completely fermented "ripe mash" for the fabrica- 
tion of vinegar ; Preparation of alcoholic liquid from filtered mash ; 
Conversion of the fermented malt wort into vinegar . . .161 

Filtration of malt vinegar in refining or rape vessels ; " Rape," what it 
is; the manufacture of malt vinegar by "fielding"; Utilization of 
sour ale and beer for vinegar . . . . . . .162 

Preparation of vinegar from sugar beets ; Vinegar from sugar, fruits, 
and berries . . . . . . . . . .163 

Receipts for making vinegar by Cadet-Gassicourt and Doebereiner ; 
Preparation of vinegar on a small scale for domestic use . .164 

Table showing the average content of sugar and free acid in the most 
common varieties of fruits ; Treatment of currant juice for the prepa- 
ration of vinegar . . . . . . . . .165 

Preparation of vinegar from bilberries ; Vinegar from berries ; Cider 
vinegar ........... 166 

Contrivance for making cider vinegar described by S. E. Todd . 167 

Vinegar from apple-pomace 168 

CHAPTER XVII. 

PREPARATION OF VINEGAR SPECIALTIES. 

Groups of specialties ; Perfumed vinegars 168 

Aromatized vinegar; Manner of dissolving volatile oils in vinegar . 169 
Preparation of aromatized vinegars . . . . . . .170 

Toilet vinegars; Mohr's volatile spirits of wine ; Aromatic vinegar; 
Henry's vinegar ; Vinaigre de quatre voleurs ; Hygienic or preven- 
tive vinegar ; Cosmetic vinegar .171 

Table vinegars ; Anise vinegar ; Anchovy vinegar ; Tarragon vinegar ; 

Compound Tarragon vinegar ; Effervescing vinegar . . .172 

Herb vinegar ; Pineapple vinegar ; Celery vinegar ; Clove vinegar ; 

Mustard vinegar ; Lovage vinegar ; Preparation of acetic ether . 1 73 
Preparation of a fluid for imparting bouquet to table vinegar ; Compo- 
sition of pure acetic ether 1 74 



XX 11 CONTENTS. 

PAGE 

Decomposition of wood at a higher temperature ; Cause of the decom- 
position of wood ; Reason why a large amount of acetic acid is pro- 
duced during the destructive distillation of wood . . . .219 

Substances given off during the destructive distillation of wood ; Actual 
facts observed in the distillation of wood ; Distillation of wood ; Re- 
torts used in the distillation of wood; Form of the retorts . . 220 

Dimensions of the retorts ; Position of the retorts ; Retorts used in 
France ......... 221 

Retorts used in England and Germany ; Vertical retorts ; Kestner's 
apparatus, illustrated and described .... 222 

Movable retorts, illustrated and described ; Modification of movable re- 
torts, illustrated and described 223 

Horizontal retorts, illustrated and described .... 225 

Apparatus for abstracting the charcoal from the carbonizing cylinders ; 
Condensers; Kestner's apparatus, illustrated and described . 227 

Collection of the gases in a gasometer; Vincent's plan for cooling the 
current of gas and rendering the vapors of acetic acid harmless, Illus- 
trated and described 228 

Dimensions for a condenser for four retorts, by Gillot ; Most suitable 
varieties of wood for the production of wood- vinegar ; Removal of 
the bark from the wood ... 

Charcoal; Composition of charcoal ; Processes tak ing' place' by h'eatina 
the wood in the retorts; Charbon roux or terrified charcoal- Red 
wood (roasted wood, boix roux) and its composition ; Charcoals avail- 
able for technical purposes 

Quantity of charcoal obtained at various temperatures j Influence of the 
degree of carbonization and of the variety of wood upon the yield of 
charcoal; Variation in the elementary composition of charcoal as 
found by Violette . 

im 'S'" : ; Properties of 'tar and of woocU 



Constituents of wood-vinegar 

Woo.1 spirit (methyl aleohol), CH.O, and it's propertied and uses ;' Ace' *** 

tone or d.methyl kctone (C 3 H 6 O) and its properties 
Determ.nat.on of the strength of W ood-vi,,egar ; Mohr's me'thod ' 
L. Rieffer's method ... -235 

Working up the wood-vinegar ; Methods by" which this' is effected' Dis' ^ 

tillation of wood-vinegar, described and illustrated 
The recreation of wood-vinegar, described and illustrated ' 

Scation of wood-vinegar according to Terreil and Chateau - lathe's 

method for the purification of wood- vinegar 
Acetic acid for technical purposes 

Preparation of crude calcium acetate ' ' ' ' 24 

. 241 
and pure sodium 

242 



CONTENTS. XX111 

PAGE 

Apparatus for roasting the pale brown sodium acetate, illustrated and 
described ; Crystallizing vessels, illustrated and described . . 244 

Mollerat's method of preparing sodium acetate 245 

Acids, besides acetic acid, which occur in wood- vinegar according to 
Barr6 246 

Vincent's method of decomposing the mother-lye ; Manner of obtaining 
wood-spirit (methyl alcohol) ; Composition of crude wood-spirit; 
Processes which take place in digesting crude wood-spirit with slaked 
lime ............ 247 

Apparatus for distilling the digested mixture, illustrated and described 248 

Further purification of wood-spirit; Purification of wood-spirit on a 
small scale ; Examination of commercial wood-spirit . . . 249 

Yield of charcoal, wood-vinegar, and wood-spirit as well as of tar; 
Stoltze's experiments on the products obtained from the distillation 
of several varieties of wood . . . . . . . .250 

Percentage of acetic anhydride which, according to Gillot, can be ob- 
tained from hard wood . . . . . . . . .251 

Results obtained by Assmus in manufacturing on a large scale ; Rothe's 
experience in obtaining acetic acid and other products from birch ; 
Yield of salable methyl alcohol according to Vincent ; Description 
of Halliday's apparatus 252 

Wood-vinegar from saw-dust ........ 253 

CHAPTER XXII. 

PREPARATION OF PURE CONCENTRATED ACETIC ACID. 

Percentage of acetic acid in the strongest vinegar which can be pre- 
pared by the process of fermentation 253 

Advisability of increasing the strength of vinegar from alcohol by the 
addition of concentrated acetic acid from wood ; Detection of empy- 
reumatic substances in acetic acid from wood ; Acetic acid from wood 
for the preservation of fruit, cucumbers, etc. ... . 254 

Manner of obtaining acetic acid from strong vinegar; Stein's method 
of increasing the boiling point of vinegar 255 

Preparation of acetic acid from commercial acetates and from those ob- 
tained from wood- vinegar ; Former method of obtaining glacial acetic 
acid ; Principal acetates now used for the preparation of acetic acid ; 
Preparation of acetic acid from normal lead acetate (sugar of lead) . 256 

Bucholz's direction for the preparation of acetic acid from lead acetate ; 
Preparation of acetic acid without distillation 257 

Decomposition of lead acetate by nitric acid ; Calcium acetate and so- 
dium acetate the basis for the preparation of acetic acid on a large 
scale ; Volckel's method of preparing acetic acid from calcium ace- 
tate . . . 258 



XXIV CONTENTS. 

PAGE 

Test for ascertaining the quantity of lime required for rectifying acetic 
acid 259 

Rectification of acetic acid, illustrated and described ; Use of the ace- 
tate prepared from crude wood- vinegar for the preparation of acetic 
acid . . - 26 

Reichenbach's method of destroying empyreumatic bodies in crude cal- 
cium acetate ; Schnedermann's method .... 261 

Preparation of acetic acid from sodium acetate . 

Yield of acetic acid from crystallized sodium acetate ; Mollerat's method 
of preparing acetic acid from sodium acetate, illustrated and described 263 

Glacial acetic acid ; Melsen's method of preparing glacial acetic acid . 265 

Calcium chloride as a by-product in the preparation of glacial acetic 
acid ; Oil of lemon as a test for pure acetic acid ; Properties of gla- 
cial acetic acid . . . . . . .266 



CHAPTER XXIII. 

ACETATES AND THEIR MANUFACTURE. 

Constitution of acetic acid ........ 266 

Solubility of acetates ; Preparation of acetates ; Potassium neutral ace- 
tate 267 

Properties and uses of potassium acetate ; Potassium acid acetate or 

potassium diacetate ......... 268 

Sodium .toetate ; Properties and uses of sodium acetate ; Sacc's method 

of preserving meats and vegetables with sodium acetate . . . 269 

Explosive mixture prepared with the use of sodium acetate; Ammo- 
nium acetate, neutral acetate of ammonia; Calcium acetate . . 270 

Barium acetate ; Mode of obtaining acetone from barium acetate . 271 

Strontium acetate ; Magnesium acetate ; Aluminium acetate ; Import- 
ance of aluminium acetate in calico printing; Mode of preparing 
aluminium acetate for the use of the calico printer .... 272 

Preparation of a mordant by decomposing alum by lead acetate ; lle- 
ceipts for preparing red liquor ; Crace-Calvert's recommendation of 
the use of sulphacetate of alumina for the preparation of mordant, 
with formulae 273 

Messrs Storck & Co.'s, of Asniferes, France, process for the manufac- 
ture of aluminium acetate from the phosphate; Manganese acetate 1 
Preparation of manganous sulphate ..... 274 

Iron acetates ; Ferrous acetate ....... 275 

Properties and use of ferrous acetate ; Neutral ferric acetate or sesqui- 
acetate of iron . .... 276 

Mode of preparing pure neutral ferric acetate . . . . 277 

Uses of the acetates of iron ; Chromium acetates . . . 278 



CONTENTS. XXV 

PAGE 

Chromous acetate ; Chromic acetate ; Nickel acetate ; Cobalt acetate ; 

Zinc acetate 279 

Acetates of copper ; Cuprous acetate ; Neutral cupric acetate, or crys- 
tallized verdigris .......... 280 

Method of obtaining neutral cupric acetate by double decomposition . 281 
Crystallization of neutral cupric acetate; Properties and uses of neutral 
cupric acetate .......... 282 

Basic cupric acetates ; Sesquibasic cupric acetate ; Dibasic cupric acetate ; 

Tribasic cupric acetate ; Varieties of verdigris found in commerce . 283 
Manufacture of verdigris in France ....... 284 

Manufacture of verdigris in England, Germany, and Sweden ; Compo- 
sition of French and English verdigris according to Philipps ; Methods 

of testing verdigris as to adulterations 285 

Uses of cupric acetates ; Scheele's green ; Schweinfurth green . . 286 
Lead acetates; Neutral acetate of lead (sugar of lead) . . .287 
Stein's method of preparing neutral acetate of lead, illustrated and 
described ........... 288 

Berard's process of preparing sugar of lead . . . . .291 

Other methods of preparing sugar of lead ...... 292 

Properties of neutral acetate of lead . . . . . . .293 

Uses of sugar of lead . .294 

Basic lead acetates ; Manufacture of white lead according to the French 

method ; Preparation of lead vinegar or extract of lead . . .295 
Lead sesquibasic acetate, triplumbic tetracetate ; Tribasic acetate of 
lead ; Preparation of tribasic acetate of lead according to Pay en ; 
Manufacture of white lead by the Clichy process and by the Dutch 
process ; Sexbasic acetate of lead ....... 296 

Uranium acetate; Tin acetate; Bismuth acetate ; Mercurous acetate t 297 
Mercuric acetate ; Silver acetate ....... 298 



PART II. 

MANUFACTURE OF CIDERS, FRUIT- WINES, ETC. 
CHAPTER XXIV. 

INTRODUCTION. 

Definition of the term wine ; Ingredients which are added to artificial 
wines ; Ripening of fruits ; Constituents of an unripe fruit . . 299 

Occurrence and behavior of pectose ; Formation and properties of 
pectine 300 

Properties of metapectine ; Action and constitution of pectase ; Pec- 
tous fermentation ; Formation of pectosic acid .... 301 



CONTENTS. 

PAGE 

Formation and properties of pectic acid ; Formation and properties of 
metupectic aeid ..... 302 

Definition of the term isomeric ; Development and ripening of a fruit 
viewed as chemical process 303 

Results of chemical researches into the changes which fruits undergo 
during their development and perfection ..... 304 

Stages which a fruit passes through during development and ripening . 305 

CHAPTER XXV. 

FRUITS AND THEIR COMPOSITION. 

Fruits used for the preparation of fruit-wines ; Compilation from 
Fresenius giving the average percentage of sugar in different varie- 
ties of fruit 306 

Compilation according to average percentage of free acid ; Compilation 
according to the proportion between acid, sugar, pectine, gum, etc. ; 
Compilation according to the proportion between water, soluble, and 
insoluble substances . . . . . . . . .307 

Composition of the juice according to its content of sugar, pectine, etc. ; 
Content of free acid in 100 parts of juice ..... 308 

Grape-sugar or glucose ; Acids; Albuminous substances . . . 309 
Pectous substances ; Gum and vegetable mucilage . . . .310 

Tannin; Difference between pathological and physical tannin . .311 
Inorganic constituents ; Fermentation ...... 312 

Chief products of vinous fermentation ; Properties of absolute alcohol; 

Succinic acid . . . . . . . . . .313 

Glycerin; Carbonic acid . . . . . . . . .314 

Quantity of carbonic acid developed during fermentation ; Alkaloid in 
wine . 315 

CHAPTER XXVI. 

PRACTICE OF THE PREPARATION OF CIDER AND FRUIT-WINES. 

Manner of gaining the juice or must from the fruit; Mr. W. O. Hic- 

kock's portable cider mill . . . . ( t gig 

Apparatus for crushing apples, illustrated and described ; Davis's star 

apple grinder, illustrated and described 317 

Presses; Manner of obtaining the juice from berries, etc. ; Manner of 

obtaining the juice from apple-pomace, etc 318 

44 Farmer's cider press," illustrated and described; "Extra power 

cider press," illustrated and described ... 319 

Revolving platform of the " extra power cider press," illustrated and 

described ., 9n 

. O & \J 

Ferguson's improved racks 321 



CONTENTS. XXV11 

PAGE 

Plain racks ; Willson's telegraph wine and cider mill, illustrated and 
described ........... 322 

Apple elevator, illustrated and described . . . . . .323 

Testing the must as to its content of acid and sugar ; Manner of finding 

the quantity of acid 324 

Determination of the sugar in must ; Manner of calculating the quan- 
tity of sugar which has to be added to the must to give the wine the 

desired content of alcohol 326 

Glucose 327 

Properties of commercial glucose ; Determination of pure sugar in glu- 
cose ; Anthon's table for finding the content of anhydrous grape- 
sugar in saturated solutions of glucose ...... 328 

CHAPTER XXVII. 

CIDER FROM APPLES AND PEARS. 

Cider from apples ; " Champagne cider" ; " Sparkling cider" . .329 

Reputation of Normandy and Herefordshire and Devonshire ciders ; 
Production of cider, in 1883, in France ; Analyses of Brittany ciders 
by Rousseau ; Analyses of pure ciders from different parts of France 
made in the Paris municipal laboratory 330 

Average composition of French ciders ; Analyses of ciders by the 
United States Agricultural Department 331 

Choice of the varieties of apples for the manufacture of cider . . 332 

Test for ascertaining the content of tannin in apples ; Mixtures of apples 
used in France for the preparation of cider; Varieties of apples 
chiefly used in New Jersey for the manufacture of cider ; List of 
apples recommended by P. Barry for cultivation in the Eastern and 
Middle States . 333 

Mode of gathering and sweating apples for the preparation of cider . 334 

Reduction of the apples to an impalpable pulp ; Diversity of opinion as 
regards the crushing of the seeds ; Treatment of the pulp ; Pressing 335 

Primitive custom of laying the cheese ; Substitution of hair-cloth and 
cotton press-cloth for straw in laying the cheese ; Manufacture of 
small cider in France ; Extraction of the juice by diffusion . . 336 

M. Jules Nanot's improved method of extracting the juice by diffusion, 
illustrated and described . . . . . . . .337 

Expressing the juice by means of the centrifugal ; Testing the juice with 
the must-aerometer and its correction if wanting in saccharine 
strength ; Fermentation of the juice 339 

Distinguishing characteristic between the fermentation of wine and 
cider; Various methods of checking fermentation; Preparation of 
very fine cider 340 



XXviii CONTENTS. 

PAGE 

Salicylic acid as an agent for cheeking fermentation; The "salicylic 

acid question" ; Manner of using salicylic acid . . . .341 
Clarification of cider ; French method of clarifying cider ; Improving 

the taste of cider 342 

Preparation of cider in the same manner as other fruit-wines ; Red 

apple-wine or red wine from cider; Sweet cider .... 343 
Dr. Denis-Dumont's directions for bottling cider .... 344 
Manufacture of cider in the Island of Jersey ; Devonshire cider ; Heating 

of cider 345 

Solution of the problem of keeping cider sweet ; Freezing of cider . 346 
Champagne eider .......... 347 

Artificial wines from cider; Burgundy; Malaga-wine; Sherry-wine . 348 
Claret-wine ; Diseases of cider ; Acidity in cider ; Viscosity or greasy 

appearance of cider ......... 349 

Turning black of cider; Turbidity of cider ; Adulteration of cider . 350 
Dr. Bremont on the adulteration of cider ; Adulteration of cider in 

France ; Minimum limit for the composition of pure cider . . 351 
Results of the investigation of American ciders by the United States 

Agricultural Department ; Manufacture of brandy from cider . . 352 
Preparation of the juice for distillation ; Brandy from plums, damsons, 

etc. ; Distillation 353 

Rectification of apple-brandy ; Pear-cider ...... 354 

Preparation of " port-wine" from pear-must ; Quince wine . . 355 

CHAPTER XXVIII. 

FRUIT-WINES. 

From small fruits ; Prevention of the turning of wine from small fruits ; 

Advantage of a mixture of various juices for the preparation of wine ; 

Means of improving the flavor and keeping qualities of fruit-wine . 356 

Selection of the fruit ; Expression of the juice ; Fermentation . . 357 

Clarification and drawing off of the wine into bottles ; Currant-wine . 358 
Composition of currant-wine, two years old ; Preparation of a very 

strong beverage from the juice of currants .... 359 

VfMous methods of preparing strawberry-wine ..... 360 

Gooseberry-wine ......... 361 

Gooseberry-champagne . . . . . . . . 3^3 

Sender's directions for the preparation of gooseberry-champagne . . 364 

Raspberry-wine * . . 365 

Blackberry-wine; Mulberry-wine; Elderberry-wine . . . SQQ 

Juniperberry-wine ; Rhubarb- wine ; Tomato-wine . . . 357 

Parsnip-wine ; Preparation of wine from stone-fruits ; Cherry-wine 368 
Morello-wine ; Plum-wine; Apricot and peach-wines; Sloe or wild 

plum-wine o fif) 



CONTENTS. XXIX 



PART III. 

CANNING AND EVAPORATING OF FRUIT, MANUFACTURE 
OF CATCHUPS, FRUIT BUTTERS, MARMALADES, JEL- 
LIES, PICKLES, AND MUSTARDS. 

CHAPTER XXIX. 

PRESERVATION OF FRUIT. 

PAGE 

Rules applying to all methods of preserving fruit . . . .371 

French method of preserving fruit, known as au Baine-Marie ; Preser- 
vation of the flesh of the fruit without boiling ..... 372 

Preparation of fruit for preserving ; Preservation of fine table pears ; 
Boiling down of fruit in large stoneware pots . . . . .373 

Preserving in air-tight cans ; National importance of this method for 
the United States and England ; Groups of canned articles embraced 
in the American trade lists . . . . . . . .374 

Difficulties in canning plums and cherries ; Fruits suitable and unsuit- 
able for canning; Selection of the fruits for canning . . .375 

List of varieties of fruit preferred by the North American factories for 
canning ; Preference of the California packers for the Bartlett pear ; 
Various styles of cans and jars 376 

Complaint against the use of tin cans ; The soldering of tin cans inside 
prohibited in England ; Manner of coating and lining the inside of tin 
cans to protect the contents from contact with the metal . . .377 

Manufacture of tin cans in the United States canneries; Division of 
labor in the canneries ; Preparation of the syrup . . . .378 

Apparatus for the expulsion of air by heating the cans ; Cleansing and 
testing the cans . . . . . . . . . .379 

Mode of heating the cans in boiling water ; Canning of tomatoes . 380 

Selection of a site for the canning establishment ; How contracts for a 
supply of tomatoes are made ; Arrangement of a canning factory . 381 

Scalding the tomatoes; Skinning the tomatoes ; Machines for filling the 
cans 382 

" Cappers" and their work ; Labelling the cans .... 383 

Trials and vexations of a canner's life ; Principal market for canned 
tomatoes 384 

Catchups ; Tomato catchup 385 

Walnut catchup ; Cucumber catchup ; Horseradish catchup . . 387 

Currant catchup ; Gooseberry catchup ; Fruit-butter, marmalade, and 
jelly; Fruit-butter; Manufacture of apple-butter .... 388 

Preparation of raising ; Manner of packing fruit-butter . . . 389 



XXX CONTENTS. 

PAGE 

Marmalade ; Derivation of the term marmalade ; Manufacture of mar- 
malade on a large scale . . . .391 

Quantity of sugar to be used ; Secret of the great reputation of the pro- 
ducts of the principal American factories ; Selection of fruit for mar- 
malade 391 

Perfumed apple marmalade ; Tutti-frutti; Jelly; Erroneous opinion as 
regards the quantity of sugar required for making jelly ; Preparation 
of apple jelly without sugar .... 392 

Use of the saccharometer in jelly boiling; Preparation of jellies from 
pears, mulberries, berries, and other small fruit . . . .393 

Preparation of jelly from stone-fruit, quinces, rhubarb, etc. ; French 
perfumed jelly ; Manufacture of apple jelly in the largest factory in 
Oswego County, New York . . . . . .394 

Arrangement of the factory ; Grating the apples and expression of the 
juice ; Description of the defecator ...... 395 

Object of the defecator ; Description of the evaporator . . . 396 

Proper consistency for perfect jelly ; Mode of packing the jelly for 
family use ........... 397 

Daily product of the factory ; Saving of the apple seeds ; Value of the 
apple seeds ; Importance of such institutions . . . . .398 

The kettle ; A kettle much used in American preserving establishments, 
illustrated and described 399 

CHAPTER XXX. 

EVAPORATION OF FRUIT. 

Great future of this mode of preserving fruit ; Difference between evap- 
orated ami dried fruit ......... 400 

Evaporating establishments about Rochester, N. Y. ; Value of the an- 
nual product of evaporated fruit in the State of New York ; Water 
eliminated by the process of evaporation ; Advantage in the cost of 
freight of evaporated fruit ; Total export of evaporated and dried 
apples from the United States during 1888, and value of the same . 401 

Enormous increase of the fruit growing industry in the United States ; 
Award of the first prize at the Paris Exhibition of 1 878 to fruit evapo- 
rated by the Alden process ; List of articles which are subjected to 
evaporation; Advantages of evaporated fruit; Unreliability of 
canned goods 402 

Experience of the steamer " Rodgers" with canned goods; Principle 
upon which the apparatus for evaporating fruit is based, and the 
theory of evaporating fruit ..... 403 

Absorption of moisture by the air .... 404 

Heat alone not sufficient for drying 40 



CONTENTS. XXXI 

PAGE 

Disadvantage of drying fruit in the oven ; Chemical analysis of a parcel 
of Baldwin apples, showing the changes effected in the composition 
of the fruit by drying in the oven, and by evaporation . . . 406 
The Alden apparatus, illustrated and described . . . . . 407 
Sun-drying apparatus, illustrated and described . 409 

The improved Williams evaporator, manufactured by S. E. Sprout, of 

Muncy, Pa., illustrated and described 410 

The American fruit evaporator manufactured by the American Manu- 
facturing Co., Waynesboro', Pa., illustrated and described . .412 
Manner of operating the Alden apparatus ...... 413 

Table of intervals at which the trays must be placed in the apparatus ; 
Manner of packing evaporated apples ...... 414 

Varieties of fruit used and manner of preparing them for evaporation . 415 
Various modes of bleaching apples and pears before evaporation ; Treat- 
ment of plums after evaporating ; Manner of placing the fruit in the 

trays 416 

Conversion of grapes into raisins by evaporating ; Preparation of toma- 
toes, pumpkins, sweet potatoes, green corn, etc., for evaporation . 417 

Manner of evaporating potatoes 418 

How evaporated potatoes should be packed ; French method of drying 
fruit in the oven . . . . . . . . . .419 

Method of drying fruit in the oven practised in central England and in 
the New England States 420 

CHAPTER XXXI. 

PREPARATION OF PICKLES AND MUSTARD. 

Manner of packing pickles ; General rules for the preparation of pickles . 420 

Preparation of spiced vinegar ; Utensils used in the preparation of 
pickles . . 421 

" Greening" pickles; List of fruits which are chiefly used for the pre- 
paration of pickles in factories ; Barberries ; Beans ; Cabbage, red 
and white ; Cauliflower ; Cucumbers ; Elderberry flowers . . 422 

English bamboo ; Gooseberries; Mixed pickles ; Mushrooms; Onions; 
Peaches; Peas; Picalilly ; Tomatoes; Walnuts . . 423 

Mustard ; English method of preparing mustard ; Substances used for 
seasoning mustard ; Gumpoldskirchner must-mustard . 424 

Moutard des Jesuites ; French mustard ; Ordinary mustard ; Frankfort 
mustard; Wine mustard ........ 425 

Aromatic or hygienic mustard ; Dusseldorf mustard ; Sour Dlisseldorf 
mustard; Sweet Kremser must-mustard; Sour Kremser must-mus- 
tard ; Moutard de maille . . . . . .426 

Moutarde aux 6pices ; Moutarde aromatis6e ; English mustard . 427 



XXXli CONTENTS. 

APPENDIX. 

PAGE 

Table I. Hehner's alcohol table 431 

Table II. which indicates the specific gravity of mixtures of alcohol and 
water 433 

Table III. showing the proportion between per cent, by weight and by 
volume of alcoholic fluids at 59 F. 434 

Table IV. showing the actual content of alcohol and water in mixtures 
of both fluids and the contraction which takes place in mixing . 435 

Table V. for comparing the different areometers with Tralles's alcohol- 
ometer 436 

Determination of the true strengths of spirit for the normal temperature 
of59F 437 

Table VI. for the determination of the true strengths of spirit for the 
normal temperature of 59 F. (15 C.) 439 

Table VII. for the determination of the true volume of alcoholic fluids 
from the apparent volume at different temperatures ; Explanation of 
the table 444 

Table VIII. of the preparation of whiskey of various strengths from spirits 
of wine ........... 446 

Table IX. for the reduction of specific gravities to saccharometer per 
cent. . . . . . . . . . . . .447 

Table X. for the comparative synopsis of the aerometers for must gene- 
rally used ........... 450 

Table XI. to Oechsle's aerometer for must ; Table XII. to Massonfour's 
aerometer; Table XIII. for comparing per cent, of sugar with per 
cent, of extract and the specific gravity . . . . . .451 

Table XIV. for determining the content of per cent, of acetic-acid 
contained in a vinegar of specific gravity (according to A. C. 
Oudemans) ... . . . . . . . . 452 

Table XV. for determining the content of per cent, of acetic-acid 
contained in a vinegar of specific gravity (according to Mohr) . 453 

Table XVI. Comparison of the scales of Keaumur, Celsius, and 
Fahrenheit thermometers . . . . . . 454 

455 



UNIVERSITY 




A PRACTICAL TREATISE 



ON 



THE MANUFACTURE OF VINEGAR, CIDER, AND 
FRUIT- WINES; 

THE PRESERVATION OF FRUITS AND VEGETABLES BY 
CANNING AND EVAPORATION, ETC. 



PART I. 

THE MANUFACTURE OF VINEGAR. 



CHAPTER I. 

INTRODUCTION. 

ORDINARY vinegar is dilute acetic acid, contaminated with 
various vegetable impurities. In this form it has been known 
from the earliest times, and its discovery must have immediately 
followed that of wine, because it is evident that at the tempera- 
ture of the Eastern countries, where the first experiments on the 
juice of the grape were made, fermentation must have set in 
rapidly, and the wine been quickly transformed into an acid 
compound. Moses mentions it and Hippocrates made use of it 
as a medicine. Its property of dissolving calcareous earth under 
the development of effervescence was known in the earliest times, 
and there cau be no doubt that its action upon metal, etc., had 
been investigated at a very remote period. Pliny relates how 
Cleopatra, by dissolving large pearls in vinegar and drinking the 
resulting liquid, won her wager of being able to consume the 
value of one million sesterces at one meal ; and Livy and 
2 



18 VINEGAR, CIDER, AND FRriT-WIXES. 

Plutarch state that Hannibal dissolved the rocks impeding his 
march across the Alps by ordering his soldiers to pour vinegar 
upon them. 

Although there can be no doubt that vinegar was in very 
general use at an early period, there was until very recently no 
definite knowledge as to the cause of its production and the mode 
of its formation. The alchemist Gerber, who lived in the eighth 
<>entury, was the first to make known the process of increasing 
the strength of wine-vinegar by distillation, and Albucases 
(about 1100) stated the fact that vinegar to be colorless has to be 
distilled over a moderate fire. Basil ins Valentinus, a monk and 
celebrated alchemist of the 15th century, knew that by the slow 
distillation of vinegar, first a weak product, and then a stronger 
one is obtained, and he was probably also acquainted with the 
process of obtaining strong acetic acid by distilling copper 
acetate (verdigris). In fact for a long time this was the only 
mode of preparing acetic acid, the product of the further rectifi- 
cation of the liquid being termed radical vinegar, spiritm Veneris, 
Venus'* vinegar, spiritm aeruninis, etc. 

Stahl and Westendorf were the first to prepare the acid in a 
pure state, and Lauranguais, in 1 759, discovered the property of 
very strong acetic acid to crystallize at a low temperature. 
Loewitz, however, in 1793, was the first to obtain it as a pure 
hydrate (glacial acetic acid). 

The formation of an acid body in the dry distillation of wood 
was already known in the 17th century. However, it was for a 
long time not recognized as acetic acid, but considered as a special 
acid (pyroligneous acid). Fourcroy and Vauquelin, in 1800, 
were the first to recognize this acid as acetic acid, and Thenard, 
in 1802, demonstrated the presence of acetic acid among the pro- 
ducts formed in the dry distillation of animal substances. 

Berzelius, in 1814, determined the exact chemical constitution 
of acetic acid, and Saussnre, in the same year, that of alcohol. 
Dr. J. Davy observed that spongy platinum, in contact with 
vapor of alcohol, l>ecame incandescent and generated acetic acid. 
Dobereiner further studied the nature of the acid, and proved 
that the alcohol was oxidized at the expense of the' atmospheric 
air, producing acetic acid and water, and that no carbonic acid 



INTRODUCTION. 19 

was formed thus pointing out the fallacy of the opinion held by 
the chemists of his time that carbonic acid was one of the pro- 
ducts of acetous fermentation. 

Schutzeubach, in 1823, one year after the establishment by 
Dobereiner of the now generally accepted theory of the formation 
of acetic acid from alcohol, introduced the quick process of man- 
ufacturing vinegar. 

Without detracting from the credit due to Schiitzenbaeh for 
the introduction of his method and the improvement in the pro- 
cess of the manufacture of vinegar, it may be mentioned that as 
early as 1732, nearly a century before, the celebrated Dutch 
chemist and physician Boerhaave made known a method for the 
fabrication of vinegar from wine, which contained the principles 
of the quick process. 

Although it is now more than sixty years since the introduc- 
tion of Schutzenbach's process into the practice, the manufacture 
of vinegar from alcohol remains nearly the same. While no 
change can be made as regards the theoretical part of the process, 
it being erected upon a foundation clearly indicated by a know- 
ledge of natural laws, many important improvements may surelv 
be introduced in the manufacture of vinegar on a large scale, this 
being especially the case where it is uninterruptedly carried on 
with the use of suitable apparatus. Many manufacturers still 
work according to Schutzenbach's original plan, i. e., they use an 
immense amount of labor for a performance which can be attained 
in a much simpler manner. 

Progress is necessary in every business, but for several reasons 
it is especially necessary for the manufacturer engaged in the 
fabrication of vinegar by the quick process. Alcohol in every 
form (whiskey, beer, wine) is everywhere subjected to a high tax, 
and the constantly increasing taxation of this fundamental 
material for the fabrication of vinegar, of course increases the 
price the manufacturer has to pay for it. Another reason why 
the manufacture of vinegar from alcohol becomes constantly more 
difficult is found in the great competition arising from the con- 
tinued improvements in the manufacture of pure acetic acid from 
wood. Not many years ago it was considered impossible to ob- 
tain entirely pure acetic acid from wood when manufacturing on 



20 VINEGAR, CIDER, AND FRUIT-WINES. 

a large scale, but the article produced at the present time may be 
almost designated as u chemically pure" in the true sense of the 
word, it containing, besides acetic acid, only water, and the most 
accurate analysis cannot detect a trace of the products of tar, which 
render unpurified wood vinegar unfit for use. 

For consumption on a large scale, especially where only a body 
of an acid taste is required, the use of so-called " vinegar essence" 
(?'. c., pure 80 to 90 per cent, acetic acid) prepared from wood, 
and which, when properly diluted, furnishes ordinary vinegar, 
will undoubtedly gradually supersede vinegar prepared from 
alcohol, it being considerably cheaper. And notwithstanding 
that the price of vinegar essence is decreasing every year, in 
regions where wood is plentiful and cheap, its manufacture is a 
well-paying industry on account of the many valuable by-products 
(tar, wood-spirit, charcoal) obtained besides acetic acid. Even at 
the present time for all industrial purposes where acetic acid is 
required, as, for instance, in the manufacture of tar colors, that 
obtained from wood is used, and the quantities consumed in the 
fabrication of table vinegar become larger every year. 

But the manufacture of vinegar from alcohol and alcoholic fluids 
will nevertheless continue to flourish because the product obtained 
from them actually possesses different properties from the pure 
acetic acid prepared from wood. Vinegar obtained from pure 
alcohol, and, still more so, that from fermented fruit juices, as 
wine, cider, skins of pressed grapes, or from malt, contain, besides 
acetic acid and water, small quantities of bodies, which on account 
of their being analogous to those occurring in wine, may be 
designated as u bouquet-bodies," and which give to the vinegar 
an agreeable smell and taste entirely wanting in acetic acid pre- 
pared from wood. These properties are so characteristic that any 
one gifted with a sensitive and practised sense of smell can at 
once distinguish pure acetic acid vinegar from that prepared from 
wine, cider, beer, etc. 

By the addition of volatile oils or compound ethers an agree- 
able odor can, of course, be imparted to vinegar obtained by 
diluting pure wood acetic acid with water, but it is impossible to 
produce the harmonious bouquet peculiar to vinegar prepared 
from alcohol or fruit juices, a similar relation existing here as 



THEORY OF THE FORMATION OF VINEGAR. 21 

between wine and so-called artificial wine. The latter can he 
made so as nearly to approach, as regards taste and smell, genuine 
wine, but a connoisseur will at once detect the difference. 

The principal defects of the process of manufacturing vinegar 
by tEe quick process in general use are not in the method itself, 
for that, as already indicated, corresponds entirely to the theoreti- 
cal conditions, and yields as good a product as can be obtained 
from the raw material used. The weak point of the process is 
found in the practical execution of it : the losses of material are 
much more considerable and greater than are absolutely necessary, 
the consumption of labor is very large, and, as every manufacturer 
knows from experience, interruptions in the regular process of 
working are of too frequent occurrence. 

All these disadvantages can be reduced to a minimum, if not 
absolutely overcome, and it is hoped sufficient hints how this can 
be done will be found in the following chapters. 



CHAPTER II. 

THEORY OF THE FORMATION OF VINEGAR. 

INDEPENDENTLY of the formation of acetic acid by the so- 
called dry distillation, the chemical processes by which acetic acid 
in larger quantities is formed are at present quite well understood, 
and will be briefly explained as follows : 

As previously mentioned, Dobereiner, in 1822, established the 
theory of the formation of acetic acid from alcohol, and the pro- 
cesses taking place thereby may be expressed by the following 
formula : 

C 2 H C + 2 = C 2 H 4 2 + H S 

Alcohol. Oxygen. Acetic acid. Witter. 

According to the above formula, acetic acid and water are 
formed by the action of oxygen upon alcohol, and hence the for- 
mation of acetic acid takes place by a partial combustion or 
oxidation of the latter. Alcohol and acetic acid are, however, 
only two members of the process, and that, besides the latter, 



22 VINEGAR, CIDER, AND FRUIT-WINES. 

other bodies are formed from the alcohol can be readily detected 
in a vinegar manufactory by the sense of smell. 

By treating alcohol with pyrolusite and sulphuric acid hence 
by the action of oxygen at the moment of its liberation from a 
combination (in its nascent state) Dobereiner obtained a body 
which he called "light oxygenated ether" (leichter Sauer- 
stoffather). Liebig, later on, studied the nature of this com- 
bination more accurately, and found that, as regards its composi- 
tion, it differed from that of alcohol only by containing two 
atoms less of hydrogen. He applied to it the term " aldehyde." 

Aldehyde is composed of C 2 H 4 O, and its formation is repre- 
sented by the formula 

C 2 H G + <> = C 2 H 4 + H 2 

Alcohol. Oxygen. Aldehyde. Water. 

In the examination of the properties of aldehyde it was shown 
that it is readily converted into acetic acid by the absorption of 
oxygen, and, based upon these facts, Liebig established a theory 
of the formation of vinegar which was for many years considered 
correct. 

Essentially Liebig's theory is as follows : 
By the exposure, under suitable conditions, of alcohol to the 
action of the atmospheric oxygen, one-third of the entire quantity 
of hydrogen contained in it is withdrawn, and aldehyde is formed. 
The latter, however, immediately further combines with oxygen, 
and is converted into acetic acid; the formation of vinegar from 
alcohol being, therefore, a partial process of combustion. 

From the present stand-point of our knowledge as regards the 
formation of acetic acid from alcohol, the correctness of this 
theory is about parallel with that according to which alcohol and 
carbonic acid are formed by the alcoholic fermentation of sugar. 
This latter process can also be illustrated by an equation in as 
simple a manner as the conversion of alcohol into acetic acid by 
aldehyde. At the present time the processes taking place in the 
formation of acetic acid from alcohol must, however, be considered 
as far more complicated than supposed by Liebig. According to 
the latter, a simple oxidation, i. e., a simple chemical process, 
takes place; but, according to the now universally accepted view, 
the formation of vinegar is due to a cheniico-physiological pro- 



THEORY OF THE FORMATION OF VINEGAR. 23 

cess with the cooperation of a living organism. Alcohol and 
oxygen alone do not suffice for this purpose, the presence of nitro- 
genous bodies and salts, besides that of an organism, being abso- 
lutely necessary. 

The French chemist, Pasteur, was the first to establish the 
formation of vinegar as a peculiar process of fermentation, and 
he maintains that a certain organism, the "vinegar ferment' 7 or 
" vinegar yeast/' consumes the alcohol, nitrogenous substances and 
salts, and separates acetic acid, aldehyde, etc., as products of the 
change of matter taking place in the living organism. On the 
other hand, the German chemist, Nageli, is of the opinion that 
the role of the organism is to bring the particles of the substance 
to be fermented (in this case, alcohol) lying next to it, into such 
vibrations as to decompose them into more simple combinations 
in this case, acetic acid, aldehyde, etc. 

The scientific dispute over these two different views is not yet 
settled, though the majority of chemists are inclined to accept 
Pasteur's theory. For the practical man it is of no consequence 
which of these views will be finally accepted as the correct one ; 
the fact that the process of the formation of vinegar is connected 
with the living process of an organism is alone of imporauce to 
him. 

As is well known, organisms producing fermentation are named 
after certain products which they form in larger quantities, the 
organism forming alcohol from sugar being, for instance, briefly 
termed " alcoholic ferment." In this sense we may also speak 
of a vinegar or acetous ferment, since a definite organism causing 
the formation of larger quantities of acetic acid from alcohol is 
known, and the cultivation of this ferment is one of the principal 
tasks of the manufacturer of vinegar. 

Numerous observations have established the fact that the pro- 
perties of forming large quantities of acetic acid are inherent 
only in this ferment. Small quantities of acetic acid are, how- 
ever, also constantly formed by other ferments, so that in examining 
products due to the process of decomposition induced by organ- 
isms, acetic acid will be generally found among them. In the 
alcoholic fermentation, at least in that of wine and bread-dough, 
acetic acid is always found. It originates in the germination of 



24 VINEGAR, CIDER, AND FRUIT-WINES. 

many seeds, and generally ap|>ears in the putrefaction of sub- 
stances rich in nitrogen, such as albumen, glue, etc. It appears 
also in the so-called lactic fermentation, the lactic acid formed by 
the specific ferment of this species of fermentation being by 
further processes of fermentation decomposed into butyric and 
acetic acids. 

Acetic acid, belonging to those bodies which may be considered 
as quite far advanced products of oxidation of higher compound 
combinations, its occurrence in living organisms is not remarkable. 
It is found in many fluids of animal origin, for instance, in meat- 
juice, milk, sweat, and urine. It also occurs constantly in the 
fresh fruit of the tamarind. What processes take place in its 
formation in these cases are not known, though it is very likely 
directly formed from certain varieties of sugar. Just as little do 
we know about the origin of the acetic acid found in the mineral 
water of Briickenau. 1 

There is quite a large series of chemical processes in which 
certain quantities of acetic acid are always formed. Sugar, starch, 
woody fibre, and, in general, all compounds known as carbohy- 
drates, when fused with caustic alkalies, always yield certain 
quantities of acetic acid, as also by themselves when subjected 
to destructive distillation. 

Among the processes by which acetic acid is produced in a 
purely chemical manner, /. r., without the cooperation of organ- 
isms, the most interesting is that by which itvS formation is effected 
by the action of very finely divided platinum (the so-called plati- 
num black) upon alcohol. Platinum black is easily prepared by 
boiling a solution of platinic chloride with an addition of an 
excess of sodium carbonate and a quantity of sugar until the 
precipitate, formed after a little time, becomes perfectly black and 
the supernatant liquor colorless. The black powder is collected 
on a filter, washed and dried by gentle heat. From its minute 
state of division this substance condenses within it several hun- 
dred times its volume of oxygen ; consequently, when the vapor 
of alcohol comes in contact with it, a supply of oxygen in a 
concentrated state is presented to it, and the platinum, without 

1 Free acetic acid is also claimed to occur in the water of a river of Brazil. 



THEORY OF THE FORMATION OF VINEGAR. 



25 



losing any of its inherent properties, effects chemical combination, 
the alcohol undergoing slow combustion, and being converted into 
acetic acid. In order that the reaction may continue, it is, of 
course, necessary to present fresh oxygen to the platinum to re- 
place that which is withdrawn. The two actions then go on 
side by side. 

This can be illustrated by an apparatus similar to Fig. 1. It 
consists of a bell glass through the mouth of which a long funnel 
passes ; the lower end of this funnel terminates in a fine point, 
so that the alcohol poured in may 
percolate very slowly. The vessel 
is placed upon supports within a 
dish in which is a saucer or small 
flat basin containing the platinum 
black. The interstice between the 
bottom of the dish and the bell 
serves for the circulation of air in 
the jar. On pouring the alcohol 
through the funnel, in the course of 
a short time the odor of acetic acid 
is perceived at the mouth from the 
acetic acid vapors, which are gene- 
rated. These condense on the sides 
of the jar and trickle to the bottom, 
where they collect in the vessel in 
the dish. It is advantageous for the 

success of the experiment to have the alcohol heated to about 90 
F. when it is poured in. By washing and glowing the platinum 
used for the oxidation of alcohol, it can be again employed for 
the same purpose. 

Independently of the purely chemical methods which, with the 
exception of that by which acetic acid is produced by the dry 
distillation of wood, are of no practical importance, the forma- 
tion of vinegar, no matter what method may be adopted, can only 
be effected in the presence of certain organisms. It has long 
been known that organisms to which the term mother of vinegar 
has been applied,- develop upon fluids containing, besides alcohol, 
certain other substances, for instance upon weak wine and beer, 







26 VINEGAR, CIDER, AND FRUIT-WINES. 

and this mother of vinegar has also been used for the fabrication 
of vinegar on a large scale. To Pasteur, however, belongs the 
incontestable merit of having more accurately examined the rela- 
tions of these organisms to the formation of vinegar. These 
examinations gave rise to his experiments on the diseased altera- 
tion of wine, which were later on succeeded by his researches on 
the formation of wine vinegar. 

Pasteur found that upon the surface of every fluid capable by 
reason of its composition of being converted into vinegar, organ- 
isms develop immediately after the commencement of the forma- 
tion of vinegar. He recognized these organisms as fungoid plants 
of a low order and called them Mycoderma aceti. More recent 
researches on the botanical nature of these plants show them to 
belong to the group of lowest fungoid organisms to which the 
term bacteria or schizomycdes has been applied. 

These plants consist of a single, generally globular or filiform 
cell, their special characteristic; being their mode of propagation, 
which is effected by the division of the cell into two and then a 
separation or splitting of both. 

The exceedingly minute size of the schizomycetes and their 
great resemblance to each other make their accurate determina- 
tion very difficult, and, hence, it is customary to name the better 
known species in accordance with the chemical products they 
form or in accordance with the phenomena they produce. Among 
the first kind may be classed those which effect the formation of 
acetic, lactic, butyric acids ; other very little known bacteria must 
be considered as the cause of the so-called nitric acid fermenta- 
tion, and again others appear in putrid fermentation. A special 
group of bacteria reaches development in animal organisms and 
give rise to terrible diseases, some causing rinderpest, others tuber- 
culosis, and various other maladies. Cholera and other epidemics 
have also recently been found to be due to certain bacteria. 

The bacteria causing disease are of course very interesting to 
the physician ; but to the manufacturer of vinegar a thorough 
knowledge of the conditions of life governing the vinegar bacteria 
is of the utmost importance, in order to conduct the fabrication 
in such a manner that disturbances shall rarely occur, and, should 
they happen, that he may be able readily to remove them. It may, 



VINEGAR FERMENT AND ITS CONDITIONS OF LIFE. 27 

therefore, be said that the entire art of the manufacture of vinegar 
consists in an accurate knowledge of the conditions of life of the 
vinegar bacteria and in the induction of these conditions of life. 
As long as the latter are maintained, the process of the formation 
of vinegar will go on without disturbance and the origination of 
new generations of vinegar ferment be connected with the con- 
version of certain quantities of alcohol into vinegar. 



CHAPTER III. 

THE VINEGAR FERMENT AND ITS CONDITIONS OF LIFE. 

A. The Vinegar Ferm,ent. 

XOTHING is as yet known about the origin of the vinegar 
bacteria, but experiments have shown these organisms to be every- 
where distributed throughout the air and to multiply at an enor- 
mous rate when fluids of a composition suitable for their nour- 
ishment are presented to them. A fluid especially adapted for 
this purpose is, for instance, thoroughly fermented, ripe wine, its 
exposure in a flat vessel and at the ordinary temperature of a 
room being sufficient to induce the augmentation of the vinegar 
bacteria reaching it from the air. 

This experiment is, however, only a certain success when exe- 
cuted with ripe wine, by which is meant wine which shows but 
little turbidity when strongly shaken in contact with air and 
exposed in a half-filled bottle to the air. Young wine contains a 
large quantity of albuminous substances in solution, and is espe- 
cially adapted for the nourishment of an organism (saccharomyces 
mesembryanthemum) belonging to the saccharomycetes. It develops 
upon the surface of such wine as a thick white skin w r hich later 
on becomes wrinkled and prevents the growth of the vinegar 
ferment. A fluid well adapted for the nourishment of the vine- 
gar ferment, and which may be used as a substitute for wine for 
its cultivation, is obtained by adding 5 to 6 per cent, of alcohol 
and about J per cent, of malt extract to water. 



28 VINEGAR, CIDER, AND FRUIT-WINES. 

By exposing ripe wine or the last-mentioned fluid at the ordi- 
nary temperature of a room, and best in a plate covered by a 
glass plate resting upon small wooden blocks to prevent the access- 
of dust, the formation of a thin veil-like coating upon the surface, 
which shortly covers the entire surface, will, in a few days, be 
observed. The wine soon shows the characteristic odor and taste 
of acetic acid, and in a few days assumes a somewhat darker 
color and deposits a slight, brownish sediment consisting of decayed 
vinegar ferment. In 14 to 21 days the fluid is entirely converted 
into vinegar, i. c., it contains no more alcohol, but instead the 
corresponding quantity of acetic acid. 

By exposing the vinegar thus obtained for a longer time to the 
air, a thick white skin of mold may happen to form on the surface, 
and, on chemically examining the fluid, the content of acetic acid 
will be found steadily to decrease, the mold which is able to convert 
the alcohol into water and carbonic acid possessing also the power 
of forming the same products from acetic acid. 

The above-described process of the destruction of the wine and 
its conversion into vinegar by a veil-like coating of the vinegar 
ferment occurs most frequently ; a thick spume, the so-called 
'mother of vinegar, may, however, also happen to form upon the 
surface, a phenomenon to which we will refer later on. 

On examining under the microscope a drop taken from the 
surface of the wine when the veil of vinegar ferment commences 
to form, a picture like that shown in Fig. 2 presents itself. In 
a somewhat more advanced stage the formations resembling 
chains and strings of beads appear more frequently, and when 
finally the development of the ferment is in full progress, it 
appears as an aggregation of numerous single cells mixed with 
double cells and many other cells strung together like beads. 
The field of vision of the microscope is then completely filled 
with a large number of colorless globules, which are present 
either singly or in combination of twos, the formations resem- 
bling chains or strings of beads occurring but seldom. In many 
of the separately-occurring formations oval forms generally 
slightly contracted in the centre are observed ; this contraction 
indicates the place where the splitting of one cell into two new 
cells takes place. By strongly shaking the fluid before viewing 



VINEGAR FERMENT AND ITS CONDITIONS OF LIFE. 29 

it under the microscope, very few of the above-mentioned bead- 
like formations will be found, but more frequently the contracted 
ones. By observing for hours a drop of the fluid containing the 
ferment in an advanced state of development, the globules strung 
together will be noticed to fall apart when at rest. Hence it may 
be supposed that in the augmentaHon of cells by splitting, the 
newly formed cells adhere together up to a certain stage, and 
later on separate in the fluid when in a quiescent state. Like 

Fig. 2. 




Development of the Vinegar Ferment. The ferment is young but in full activity. 

X 500. 

every other organism the vinegar ferment only lives for a certain 
time, and after dying, sinks below the fluid and forms upon the 
bottom of the vessel the above-mentioned sediment. The latter 
appears under the microscope in the same form as the living fer- 
ment, but differs from it in being less transparent and of a 
brownish color. The augmentation of the vinegar ferment takes 
place very rapidly, and it will be found in a few hours after the 
commencement of its development in all stages of life upon the 
surface of the fluid, it being possible to distinguish cells of from 
1.5 to 3.5 micromillimetres in size. 1 

The vinegar ferment requiring /ree oxygen for its augmentation 

1 One micromillimetre = v millimetre. 



30 VINEGAR, CIDER, AND FRUIT-WINES. 

can exuberantly grow only upon the surface of the nourishing 
fluids. By filling a bottle about four-fifths with wine, and after 
allowing the vinegar ferment to develop, closing the mouth of the 
bottle with the hand and submerging the neck of the bottle in 
water, the fluid will be seen to rise for some time in the bottle 
and then remain stationary. A determination of the content 
of acetic acid immediately before the commencement of this ex- 
periment, and a few days after, shows but a slight increase of 
acetic acid, because after the. ferment has consumed the free oxygen 
present in the bottle, the essential condition for its further develop- 
ment is wanting, and it must cease its activity without, however, 
perishing. It may here be remarked that the vinegar ferment, 
like the majority of bacteria, possesses an extraordinary vitality ; 
under unfavorable conditions it passes into a kind of quiescent 
state, during which no perceptible increase of cells takes place. 
It may remain in this state for a long time without suffering 
destruction, and recommences augmentation and propagation in a 
normal manner as soon as the conditions required for its nourish- 
ment are again presented. 

The great rapidity of the augmentation of the vinegar bacteria 
can be shown by an experiment of some importance to the prac- 
tice. Pour into a shallow vat of about three feet in diameter a 
fluid suitable for the nourishment of bacteria, and divide upon 
the surface by means of a thin glass rod small drops of wine, upon 
which the frequently mentioned veil has been formed. In a few 
hours the entire surface of the fluid in the vat will be covered 
with vinegar bacteria, spreading concentrically from the points 
where the drops of wine have been distributed. From this it will 
be seen that the cultivation of the ferment for the purpose of 
manufacturing vinegar offers no difficulties, provided all con- 
ditions required for the propagation of this organism be observed. 

B. Now*wkmy conditions of the vinegar ferment. 

.Through many observations and experiments made in practice 
the conditions most favorable for the development of the vinegar 
ferment, and for converting in the shortest time the largest quan- 
tity of alcohol into acetic acid have been determined. These con- 



VINEGAR FERMENT AND ITS CONDITIONS OF LIFE. 31 

ditions will first be briefly enumerated and then the separate 
points more fully discussed. 

For the vinegar bacteria to settle upon a fluid, and for their 
vigorous augmentation the following factors are required : 

1. A fluid, which, besides alcohol and water, contains nitro- 

genous bodies and alkaline salts. The quantities of these 
bodies must, however, not exceed a certain limit. 

2. The fluid must be in immediate contact with oxygen (at- 

mospheric air). 

3. The temperature of the fluid and the air surrounding it 

must be within certain limits. 

As regards the composition of the nourishing fluid itself, it 
must contain all the bodies required for the nourishment of a 
plant of a low order. Such substances are carbohydrates, albu- 
minates, and salts. Alcohol must be named as a specific nourish- 
ment of the vinegar ferment, provided the supposition that the 
latter consumes the alcohol and separates in its place acetic acid 
is correct. The quantity of alcohol in the fluid intended for the 
fabrication of vinegar must, however, not exceed a certain limit, 
a content of 15 per cent, appearing to be the maximum at which 
acetous fermentation can be induced. But even a content of 12 
to 13 per cent, of alcohol is not very conducive to the vegetation 
of the vinegar ferment, and every manufacturer knows the diffi- 
culty of preparing vinegar from such a fluid. Like a high con- 
tent of alcohol, a large quantity of acetic acid in the nourishing 
fluid exerts also an injurious influence upon the vinegar ferment. 
Upon a fluid containing 12 to 13 per cent, of acetic acid, and 1 
to 2 per cent, of alcohol, the ferment vegetates only in a sluggish 
manner, and considerable time is required to convert this small 
quantity of alcohol into acetic acid. 

That the vinegar ferment cannot live in dilute alcohol alone 
may be shown by a simple experiment. By placing fully developed 
ferment upon a fluid consisting of only water and alcohol, a very 
small quantity of acetic acid is formed, but the ferment perishes 
in a short time it starves to death. A fluid suitable for the 
nourishment of the ferment must therefore contain the above- 
mentioned nourishing substances, sugar, dextrine, or similar com- 
binations occurring in wine, malt extract, beer, being generally 



32 VINEGAR, CIDER, AND FRUIT-WINES. 

employed as carbohydrates. These fluids further contain nitro- 
genous combinations which may serve as nutriment for the 
ferment, and also considerable quantities of phosphates. Hence 
by an addition of wine (or must), malt extract, beer, or any fruit 
wine (apple or pear cider) to a mixture of alcohol and water, a 
fluid can be prepared, which contains all the substances essential 
to the nourishment of the ferment. 

The quantity of these nourishing substances, as compared with 
that of alcohol, is very small, the quantity by weight of vinegar 
ferment required for the conversion of a very large amount of 
alcohol into vinegar being only a few fractions of one per cent, of 
weight of alcohol used. Hence the manufacturer may be very 
economical with the addition of nourishing substances to the fluid 
to l>e converted into vinegar without having to fear that the fer- 
ment will be stinted. 

The vinegar ferment is very sensitive to sudden changes in the 
composition of the fluids upon which it lives and suffers injury 
by such changes which is recognized by diminished propagation 
and decreased conversion of alcohol into acetic acid. 

By bringing, for instance, vinegar ferment which vegetated in 
an entirely normal manner upon a fluid containing only 4 to 5 
per cent, of alcohol, upon one with a content of 10 to 11 per 
cent., its augmentation, as well as fermenting energy, decreases 
rapidly and remains sluggish until a few new generations of cells 
have been formed which are better accustomed to the changed 
conditions. By bringing, on the other hand, a ferment from a 
fluid rich in alcohol upon one containing a smaller percentage the 
disturbances in the conditions of the ferment can also be observed, 
but they exert a less injurious influence upon the process of the 
formation of vinegar than in the former instance. 

The process of nourishment of the vinegar ferment must, how- 
ever, not be understood to consist simply in the consumption of 
sugar, albuminates, and salts. It differs according to the compo- 
sition of the nourishing fluid, and is so complicated as to require 
a very thorough study for its explanation. If, for instance, wine 
is converted into vinegar, and the composition of the latter com- 
pared with that of the original wine, it will be found that not 
only the alcohol has been converted into acetic acid and the fluid 



VINEGAR FERMENT AND ITS CONDITIONS OF LIFE. 33 

has suffered a small diminution of extractive substances and salts, 
which might be set down to the account of the nourishment of 
the ferment, but that the quantity of tartaric, malic, and succiuic 
acids has also decreased as well as that of glycerine, and of the 
latter even nothing may be present. Hence it must be supposed 
that the vinegar ferment also derives nourishment from these sub- 
stances, or that its fermenting activity acts upon them as well as 
upon the alcohol. There is finally the very important fact for 
the practice, which has not yet been sufficiently explained, that 
the vinegar ferment develops more rapidly upon a fluid which, 
besides the requisite nourishing substances, contains a certain 
quantity of acetic acid, than upon a fluid entirely destitute of it.. 
Regarding the supply of air, it may be said that, while for mere 
existence the vinegar ferment requires comparatively little air, 
large quantities of it are necessary for its vigorous augmentation 
and fermenting activity. In the practice it is aimed to accom- 
plish this by exposing the fluid in which the ferment lives in thin 
layers to the action of the air, and, in fact, upon this the entire 
process of the quick method of fabrication is based. 

Besides the above-mentioned factors the temperature to which 
the ferment is exposed takes an important part as regards its 
development. The limits at which the augmentation of the fer- 
ment and its vinegar-forming activity are greatest, lie between 
H8 and 95 F. Above this limit the formation of vinegar 
decreases rapidly and ceases entirely at 104 F. By again 
reducing the temperature to 86 F. the ferment reassumes its 
activity. At a temperature exceeding 104 F. the ferment suffers 
perceptible injury ; heated to 103 F. it becomes sensibly weaker, 
and at first augments very slowly, regaining its original vigorous 
development only after several generations. By raising the tem- 
perature of the fluid to 122 F. the ferment perishes. 

To low temperatures the ferment seems to be less sensitive. 
By lowering the temperature of a fluid showing an exuberant 
growth of ferment to 50 F. or less, the formation of vinegar 
continues, though at a very much reduced rate. Experiments 
especially made for the purpose have shown that by exposing 
wine with a growth of ferment to a temperature of 14 F. so 
that it was converted into ice, the ferment recommenced to grow 
3 



34 VIXEGAR, CIDER, AND FRUIT-WINES. 

and to form acetic acid after melting and heating the fluid to 59 
F. It should, however, be expressly stated that while vinegar 
ferment in a state of development keeps up a slow growth when 
the fluid is reduced to a low temperature, it is very difficult to 
rear it upon a cold fluid. This is very likely the reason why 
acetous degeneration is not known in cold wine cellars, while in 
those having a temperature of over 59 F. this dreaded process 
can only be guarded against by the greatest care. . 

Since the augmentation of the ferment and its fermenting 
activity increase with a higher temperature, it would appear most 
suitable to keep the temperature of the fluid to be converted into 
vinegar as near the uppermost limit of 95 F. as possible. Ex- 
perience, however, has shown that at this temperature disturb- 
ances are of frequent occurrence in the generators, and for this 
reason one of 86 to 89 F. is generally preferred. The process 
of the formation of vinegar itself explains why disturbances may 
easily occur at a high temperature. It is a chemical (oxidizing) 
process in which a certain quantity of heat depending on the 
quantity of alcohol to be oxidized within a certain time is always 
liberated. If now by the use of a temperature close to 95 F. 
the activity of the ferment is strained to the utmost, a large quan- 
tity of alcohol is in a short time converted into acetic acid, and 
consequently so much heat is liberated that the temperature in the 
generator rises above the permissible maximum and the ferment 
immediately ceases its activity. Thus it may happen that in a 
generator which has satisfactorily worked for some time, the for- 
mation of vinegar ceases all at once, and on examining the ther- 
mometer placed on the apparatus the cause will be generally found 
to be due to too high a temperature. 

Mother of Vinegar. 

In connection with the description of the conditions of life of 
the vinegar bacteria, a peculiar formation, playing in many cases 
a role in the practice of the fabrication of vinegar, has to be 
mentioned. This is the so-called mother of vinegar, the term 
having very likely been applied to it on account of its causing 



VINEGAR FERMENT AND ITS CONDITIONS OF LIFE. 35 

acidification when brought into a fluid suitable for the formation 
of acetic acid. 

The mother of vinegar occurs generally only in fluids which, 
besides alcohol, contain large quantities of extractive substances, 
for instance, wine or beer. After the ordinary vinegar ferment 
has for some time grown upon the surface of these fluids a coat- 
ing is formed which acquires a thickness of up to j- inch, and 
such consistency, that with some care, it can be lifted as a cohe- 
rent mass from the fluid. The mother of vinegar then represents 
a very elastic transparent mass of a yellowish-white color and 
closely resembles an animal hide swelled to a high degree by treat- 
ment with water. 

Upon the side of the skin exposed to the air numerous molds 
frequently settle and form complete sods of the well-known gray 
green or yellow color. This is, however, only a secondary phe- 
nomenon, the mother of vinegar being especially adapted as a 
basis for the development of molds. By exposure to the air, best 
upon a porous support (a plate of brick or gypsum), the mother 
of vinegar quickly decreases in bulk and finally dries to a very 
thin layer resembling paper. Viewed under the microscope the 
mother of vinegar appears as a mass entirely devoid of structure 
in which numerous individuals of the vinegar ferment are 
imbedded. 

Several opinions have been expressed as to the nature of the 
mother of vinegar, and among others that it is a special variety 
of vinegar ferment, w r hich, however, cannot be accepted as correct, 
it being far more probable that its formation depends on the 
nature of the fluid upon which ordinary vinegar ferment grows. 
As previously mentioned, the mother of vinegar reaches develop- 
ment upon young wine and beer, and these fluids always contain 
certain quantities of albuminous substances in solution. Now it 
is very probable that the mother of vinegar consists of pecu- 
liarly changed albuminous substances eventually also of carbo- 
hydrates and that innumerable organisms of the vinegar ferment 
are distributed throughout the mass which cause the acidification 
of fluids to which it is transferred. This view is supported by 
its composition, with regard to its organic substance, as deter- 
mined by Mulder. 



36 VINEGAR, CIDER, AND FRUIT-WINES. 

Composition of the mother of vinegar, according to Mulder : 

Carbon 46 - 8 

Hydrogen ....-' 6 - 4 

Nitrogen 3 - 9 

Oxygen 42< ^ 

According to R. D. Thomson, who also examined the mother 
of vinegar, its composition is : 

Organic substance .{ C ^ lul Se } about 5 per cent. 

I al lin-ini nrtim snhstaiioe t 



'I albuminous substance 
J potash, lime 
I phosphoric acid 
Water ..... more than 94 



salts . . . i*: ;' - ., " 



These analyses justify the opinion that albuminous substances 
as well as carbohydrates participate in the formation of the mother 
of vinegar. (In beer carbohydrates are always present, while in 
wine extractive substances occur which, at least, are closely allied 
to the carbohydrates.) An experiment especially made for the 
purpose conclusively proves that the formation of the mother of 
vinegar depends on the presence of the above-mentioned sub- 
stances in the fluid upon which it grows. 

A thick cover of mother of vinegar had formed upon young 
wine ; this being removed it was in a few days replaced by a new 
growth, which, however, was not quite so thick. This cover 
being also removed a third but very slight one was formed until 
finally a cover of mother of vinegar was no longer developed 
upon the fluid, but only normal vinegar ferment. The explana- 
tion of this phenomenon is that with the decrease of nitrogenous 
substances in the wine, the conditions for the development of 
mother of vinegar became constantly more unfavorable until 
finally nothing but vinegar ferment could form. By transferring 
a piece of mother of vinegar to a fluid composed of alcohol, water, 
and some old wine (hence such as contained only very small quan- 
tities of nitrogenous substances) the slimy mass remained floating 
in the fluid without increasing or undergoing alteration, while the 
surface became covered with ordinary vinegar ferment and acidi- 
fication proceeded in a normal manner. 

The formation of mother of vinegar can always be successfully 
attained by exposing young wine to the air until the commence- 



VINEGAR FERMENT AND ITS CONDITIONS OF LIFE. 37 

ment of the formation of mold is indicated by the appearance of 
white dots and then transferring the wine to a room having a 
temperature of 86 F. At this temperature the development of 
the vinegar ferment proceeds so vigorously that it suppresses the 
mold ferment, and the peculiar mass constituting the mother of 
vinegar soon forms upon the surface. 

Mother of vinegar occurs so generally in young wine (which 
is chiefly used for the preparation of wine vinegar) that its for- 
mation was considered as inseparably connected with that ot 
acetic acid from alcohol, while actually it is only due to the pecu- 
liar constitution of the fluid to be converted into vinegar. In 
many places this opinion is still entertained, and especially where, 
as is generally the case, the manufacture of vinegar from wine is 
yet carried on in the primitive way of centuries ago. In speaking 
of the preparation of vinegar from wine, it will be shown that the 
conversion can be effected by means of the ordinary vinegar 
ferment without the appearance of mother of vinegar. 

Summary. 

Briefly stated the points of the theoretical conditions of the 
formation of vinegar of importance to the manufacturer are : 

1. Acetic acid is formed during many chemical conversions; 

for the manufacture of acetic acid, and consequently of 
vinegar on a large scale, only two methods are available, 
viz., the preparation of vinegar from alcohol by fermenta- 
tion, or the obtaining of acetic acid by dry distillation of 
wood. 

2. All alcoholic fluids formed by vinous fermentation of saccha- 

riferous plant juices or fermented malt extracts are suitable 
for the preparation of vinegar by fermentation. Specially 
prepared mixtures of water, alcohol, and vinegar may 
also be used for the purpose, provided they contain small 
quantities of certain organic substances and salts, and not 
over 14 per cent, of alcohol. 

3. The acetous fermentation is induced by a microscopic organ- 

ism belonging to the bacteria, and the conversion of the 
alcohol into acetic acid is in a certain ratio to the aug- 
mentation of this organism. 



38 VINEGAR, CIDER, AND FRUIT-WINES. 

4. Besides the substances mentioned in 2, the vinegar ferment 

requires for its vigorous development free oxygen and a 
temperature lying between 68 and 95 F. 

5. In the acetous fermentation the greater portion of the alcohol 

is converted into acetic acid and water ; besides these small 
quantities of other products are formed which are partially, 
not yet thoroughly, known. In the conversion of wine, 
beer, etc., other combinations contained in the fluids, 
besides alcohol, are also essentially changed. 



CHAPTER IV. 

PRODUCTS OF ACETOUS FERMENTATION. 

THE formation of vinegar by fermentation being a chemico- 
physiological process, many and complicated chemical processes 
must take place in the fluid to be converted into vinegar in order 
to produce all the combinations required for the augmentation of 
the ferment. Attention cannot be too frequently called to the 
fact that from the standpoint of the manufacturer, the regular 
augmentation of the ferment is the main point of the entire fab- 
rication, the quick conversion of the alcohol contained in the fluid 
being a necessary consequence of it. 

The body of the ferment, however, contains cellulose, albu- 
minous substances, very likely fat and other combinations not yet 
known, all of which must be formed from the nourishing sub- 
stances (sugar, dextrine, albuminous substances, etc.), present. 
It being very probable that a portion of the alcohol contained in 
the fluid is consumed for this purpose, a small but nevertheless per- 
ceptible loss of alcohol will occur in the fabrication. It would 
be erroneous to suppose that the conversion of alcohol into acetic 
acid and water is effected according to the Formula given on p. 21 ; 
a certain portion of it is always converted into other combinations, 
the nature and formation of which can only be, to a certain extent, 
explained. 

In the vinous fermentation, which of all fermenting processes 



PRODUCTS OF ACETOUS FERMENTATION. 39 

has been most thoroughly studied, we find that besides alcohol 
and carbonic acid large quantities of glycerin and succinic acid 
and probably other bodies are formed from the sugar, which must 
undoubtedly be classed among the products of vinous fermenta- 
tion. Similar processes, no doubt, take place in the acetous fer- 
mentation, and besides acetic acid and water other little known 
products of fermentation are regularly formed. 

According to the nature of the sacchariferous fluids subjected 
to vinous fermentation small quantities of certain bodies called 
fusel oils are formed which are decidedly products of fermenta- 
tion. They impart to the fermented fluid, as well as to the alcohol 
distilled from it, such characteristic properties that from the odor 
of the alcohol a correct judgment can be formed as to the material 
employed in its preparation. 

In the conversion of such a fluid, or of alcohol prepared from 
it, into vinegar, the fusel oils are also changed very likely oxi- 
dized and with some experience the material (wine, beer, malt, 
etc.), from which the vinegar has been made can be determined 
by the sense of smell. The quantities of aromatic substances 
which reach the vinegar in this manner are, of course, very small, 
but they must nevertheless be classed among the most important 
products of acetous fermentation, they being very characteristic 
as regards the nature of the vinegar. Of the products of acetous 
fermentation, besides acetic acid, aldehyde and acetal are best 
known, these combinations appearing always, even if only in 
small quantities, in the fabrication of vinegar according to the 
methods customary at the present time. 

Acetic Aldehyde or Acetaldehyde. 

Acetic aldehyde, commonly called simply aldehyde (from alcohol 
dehydrogenatum), is obtained by oxidizing spirits of wine by 
means of manganese dioxide (pyrolusite) and sulphuric acid, 
chromic acid, or platinum black, in the presence of air, or if alcohol 
or ether is burning without a sufficient supply of air. It is also 
formed by heating a mixture of acetate and formate of calcium. 
It is contained in considerable quantities in the first runnings 
obtained in the manufacture of spirit of wine. 



40 VINEGAR, CIDER, AND FRUIT-WINES. 

To prepare pure aldehyde 3 parts of potassium clichromate in 
small pieces are placed in a flask surrounded by a freezing mix- 
ture and a well-cooled mixture of 2 parts of spirit of wine, 4 of 
sulphuric acid, and 4 of water added. After connecting the flask 
with a condenser the freezing mixture is removed ; a violent reac- 
tion soon sets in and the liquid begins to boil. The vapors have 
first to pass through an ascending tube surrounded by warm water 
at about 122 F. Alcohol and different products are condensed 
and flow back while the vapor of the aldehyde, after having 
passed through a descending condenser, is absorbed in anhydrous 
ether. 

Pure aldehyde thus obtained is a colorless liquid of the com- 
position C 2 H 4 O. Its specific gravity is 0.800, and it boils at 
about 71.5 F. It has a pungent and suffocating smell and is 
readily soluble in water, alcohol, and acetic acid. Like all the 
aldehydes it is very easily oxidized and acts, therefore, as a pow- 
erful reducing agent. Thus, on heating it with a little ammonia 
and nitrate of silver, metallic silver separates out, coating the 
sides of the vessel with a bright mirror. It combines with ammo- 
nia and forms a crystalline compound which has a peculiar smell 
of mice. 

Though it is likely that in the fabrication of vinegar by the 
quick process, besides aldehyde, acetic and formic ethers are 
formed, they are of comparatively little importance for our pur- 
poses. Of more importance, however, is acetal, the formation of 
this combination affording an interesting insight into the compli- 
cated processes accompanying the conversion of alcohol into acetic 
acid. 

Acetal. 

This combination is best prepared by distributing pieces of 
pumice, previously moistened with 25 per cent, alcohol over a 
large glass plate, placing watch crystals containing platinum black 
upon the pieces of pumice and covering the whole with a large 
bell-glass. The alcohol absorbed by the pumice being converted 
into acetic acid, 60 per cent, alcohol is poured upon the plate and 
the air in the bell-glass from time to time renewed. In a few 



PRODUCTS OF ACETOUS FERMENTATION. 41 

weeks a quite thick fluid of an agreeable odor has collected upon 
the glass plate. This is collected and distilled, the portion passing 
over at 219 F., being collected by itself. 

Pure acetal is composed of C fi H l4 O 2 . It is a colorless liquid, 
has a specific gravity of 0.821, and boils at 219.2 F. It has a 
refreshing odor, calling to mind that of fruit ethers. By oxi- 
dizing agents it is quickly converted into acetic acid. Nitrate of 
silver in the presence of ammonia is, however, not reduced by it, 
and it remains unchanged on boiling with potash lye. From its 
composition acetal may be considered from several points of view. 
It may be regarded as an ethyl alcohol (glycol) C 2 H 6 O 2 , in 
which two atoms of hydrogen have been replaced by two mole- 
cules of the radical ethyl C 2 H 5 , hence thus 

f } - ^hyl-glycol 



C 6 H 14 O 2 acetal. 

This view of the composition of acetal is supported by the fact 
that methyl or amyl can be substituted for either one or both mole- 
cules of ethyl in the combination. 

According to other opinions, acetal may be considered as a com- 
bination of aldehyde and aldehyde ether : 

C 2 H 4 O aldehyde 

C 4 H 10 O aldehyde ether 

C 6 H, 4 O 2 acetal, 

or as a combination of aldehyde with ethyl alcohol, one molecule 
of water in the latter having been replaced by the aldehyde : 

Ethyl alcohol : 2(C.H 6 O) JI 2 O = C 4 H/) 

aldehyde C 9 H,O 
acetal C 6 H J4 O 2 

By keeping in view the fact that the process of the formation 
of vinegar is an oxidation of the alcohol which does not proceed 
with equal energy in all parts of the apparatus, it will be under- 
stood that during this process aldehyde, acetal, and acetic ether 
can be formed which, if the operation be correctly conducted, will 
be finally converted into acetic acid, though small quantities of 
them will be found in the vinegar when just finished and exert 
an influence upon its constitution. 



42 VINEGAR, CIDER, AND FRUIT-WINES. 

Acetic Acid. 

Pure acetic acid, C 2 H 4 O 21 , cannot be directly obtained from 
vinegar, but only from acetates by methods which will be described 
later on. The strongest acetic acid which can be prepared is 
known as glacial acetic acid, from its crystallizing in icy leaflets 
at about 40 F. Above a temperature of about 60 F. the 
crystals fuse to a thin, colorless liquid of an exceedingly pungent 
and well r known odor. When diluted it has a pleasant acid taste 
and agreeable odor. Pure acetic acid is a powerful restorative 
when applied to the nostrils in impending fainting. It is the 
strongest of the organic acids and nearly as acrimonious as sul- 
phuric acid. When dropped on the skin it acts as an escharotic, 
speedily raising a blister and producing much heat and rapid 
inflammation ; when taken into the mouth or applied to any 
mucous membrane it blackens like sulphuric acid. Highly con- 
centrated acetic acid is a solvent of many volatile oils, resins, 
albuminates, and glue; the ability to dissolve lemon oil is used in 
the practice as a test for the high concentration of acetic acid, 
since in the presence of only 2 per cent, of water in the acid 
lemon oil is no longer dissolved by it. 

The specific gravity of pure acetic acid is at 59 F. : 

According to Onderaans 1.0553 

Roscoe 1.0564 

Kopp 1.0590 

Mendelejeff 1.0607 

Mohr 1.0600 

According to Mohr's determinations, the specific gravity of 
pure acetic acid varies much at different temperatures, it being 

1.0630 at 54.5 F. 

1.0600 " 59.0 " 

1.0555 "i 68.0 " 
1.0498 77.0 " 

1.0480 79.0 " 

Mixtures of acetic acid and water show a peculiar behavior in 
regard to their specific gravity ; the latter rises steadily until the 
content of water amounts to from 20 to 23 per cent. ; the density 
of the liquid then diminishes so that a mixture containing 46 



PRODUCTS OF ACETOUS FERMENTATION. 43 

per cent, of water shows the same specific gravity as the anhy- 
drous acid. From this point on, the specific gravities of the 
mixtures decrease with the increase in the content of water. 

This peculiar behavior of the mixtures renders the accurate 
determination of the content of acid in a concentrated mixture 
by means of the aerometer impossible. There are a number 
of determinations of specific gravities of acetic acid with varying 
contents of water (by Mohr, von der Toorn, Oudemans, etc.), 
but they differ considerably from each other, like the tables at the 
end of this volume, so that, while the specific gravity test answers 
very well for the determination of the amount of anhydrous acid 
in dilute solutions, it is very fallacious when the acid increases in 
strength, and an accurate determination can only be effected by 
chemical methods. 

Highly concentrated acetic acid has recently found considerable 
application in photography and surgery, and frequently occurs in 
commerce in the form of so-called vinegar essence. The acetic 
acid occurring under this name is generally prepared from wood 
vinegar and is only fit for the preparation of table vinegar when 
a chemical examination shows no trace of tar products, which are 
formed in abundance, besides acetic acid, in the dry distillation of 
wood. 

In regard to the composition of acetic acid, it may be men- 
tioned that one atom of hydrogen can be readily replaced by 
univalent metals or univalent compound radicals which may be 
expressed by 

H lo 

c 2 H 3 or 

TT ~j 

wherebv the acetic acid is considered 'as water tr > O in which 

M J 
one atom of hydrogen is replaced by the compound radical 

C 2 H 3 O = acetyl 

If the one atom of hydrogen standing by itself be replaced by 
a univalent metal a neutral acetate is formed, for instance : 

Na ) Q 
C 2 H 3 OJ C 
or sodium acetate. 

If this atom of hydrogen is replaced by a uuivalent compound 



44 VINEGAR, CIDER, AND FRUIT-WINES. 

radical, for instance by methyl CH 3 or ethyl C 2 H 3 , the so-called 

compound ethers are formed. 

CH 3 \ n C 2 H 5 \ 

C 2 H 5 Oj C 2 H 3 0/ C 

Acetic acid-methyl ether. Acetic acid ethyl ether. 

If a bivalent metal or compound radical yields a neutral com- 
bination with awtic acid, the substituted hydrogen in two mole- 
cules of acetic acid must evidently be replaced by this bivalent 
metal, for instance : 

Ca \ 

2(C a H/>) j J * 

Neutral calcium acetate. 

Theoretical Yields of Acetic Acid. 

In industries based upon chemical processes a distinction is 
made between the theoretical and practical yields. 

By theoretical yield is understood the quantity of the body 
to be manufactured which would result if no losses of substance 
were connected with the chemical process ; the practical yield, 
on the other hand, is that in Avhich such losses are taken into 
account, the average being ascertained by long-continued compari- 
son of daily yields. The closer the practical yield approaches 
the theoretical, the more suitable the method pursued in the fabri- 
cation evidently is, and thus the manufacturer, who has a clear idea 
of the theoretical yield, can readily judge of the value of his 
method by comparing it with the practical yield attained. 

Now suppose no loss of substance (by evaporation or forma- 
tion of other combinations) occurs in the conversion of alcohol 
into acetic acid, it can be readily calculated from the composition 
of the two bodies how many parts by weight of acetic acid can 
be formed from a determined number of parts by weight of 
alcohol. 

Alcohol has the composition C 2 H 8 O, or an atomic weight of 46, 
because : 

C 9 ...... 24 

H n = 6 

O = 16 

Makes 46 



PRODUCTS OF ACETOUS FERMENTATION. 45 

The composition of acetic acid is C 2 H 4 O 2 aud its molecular 
weight 60, because : 

C 2 = 24 

H<- 4 

O 2 = 32 

Makes . . 60 

Hence from 46 parts by weight of alcohol 60 parts by weight 
of acetic acid may be formed, or by reducing the ratio to 100 
parts of alcohol it follows that 100 parts by weight of alcohol 
must yield 130.43478 parts by weight of acetic acid. (The 
increase in weight has to be attributed to the absorption of one 
atom of oxygen, atomic weight 16, against the loss of two atoms 
of hydrogen, atomic weight 2.) Since these two atoms of hydro- 
gen are themselves oxidized to water by the absorption of oxygen, 
the total yield from 100 parts by weight of alcohol would be : 

Acetic acid 130.43478 parts by weight. 

Water 39.13043 " " " 



Total .... 169.56521 parts by weight. 

The quantity of oxygen required to form acetic acid and water 
from 46 parts by weight of alcohol, amounts to 32 parts by 
weight, hence for 100 to 69.562 parts by weight. The oxygen 
is conducted to the alcohol in the form of air, and it can be 
readily calculated how much of the latter is required to convert 
a given quantity of alcohol, for instance 100 grammes, into acetic 
acid. In round numbers the air contains in 100 parts by weight 
23 parts by weight of oxygen. Since 1 liter of air of 68 F., 
i. e., of that temperature which should at the least always prevail 
in the vinegar generators, weighs 1.283 grammes, the oxygen con- 
tained in it weighs 0.29509 grammes. Since, as above stated, 
69.562 parts by weight are necessary for the conversion of 100 
parts by weight of alcohol into acetic acid, it follows that 235.70 
liters of air are required for the same purpose. 

Examinations as to the content of oxygen in the 'air escaping 
from weir-conducted vinegar generators have shown that on an 
average only one-quarter of the entire content of oxygen is con- 
sumed in the formation of vinegar; hence four times the theorcti- 



46 VIXEGAR, CIDER, AND FRUIT- WIXES. 

cally calculated quantity of air must pass through the apparatus 
to completely convert the alcohol into acetic acid. Hence 100 
grammes of alcohol require at least 942.92 liters of air for their 
conversion into acetic acid, and, without being far wrong, it may 
be assumed that in a vinegar factory, in round numbers, 1000 
liters or one cubic metre of air are required for every 100 grammes 
of alcohol to be converted into acetic acid. 

A vinegar generator can, on an average, convert daily 3 liters 
of alcohol into acetic acid ; 3 liters of absolute alcohol (specific 
gravity 0.794) weigh 2382 grammes. Now, if, as stated above, 
1 cubic metre of air is required for every 100 grammes of alcohol, 
it follows that 23.82 cubic metres, or 23,820 liters of air must 
pass daily through each vinegar generator in operation.* 

Calculated to 16 working hours a day, somewhat more than 0.4 
liters (more accurately 0.413 liters) must pass every second through 
the generator in order to supply the quantity of oxygen required 
for the conversion of alcohol into acetic acid. 

Since the formation of vinegar has theoretically to be con- 
sidered as a process of combustion, in which of 46 parts by 
weight of alcohol 2 parts by weight of hydrogen, or of 100 parts 
by weight of alcohol 4.34782 parts by weight of hydrogen, are 
consumed, the quantity of heat liberated by the conversion of 
100 parts by weight of alcohol into acetic acid can also be calcu- 
lated. By combustion 1 gramme of hydrogen yields 34.126 
units of heat, and hence 4.34782 grammes of hydrogen 148.373 
units of heat, i. e., in the conversion of 100 grammes of alcohol 
into acetic acid sufficient heat is liberated to heat 148.373 kilo- 
grammes of water from C. to 1 0., or 1.48 kilogrammes from 
C. to boiling, and thus a considerable development of heat is 
caused by the rise of temperature in the apparatus in which a 
vigorous formation of vinegar takes place. 

In answer to the question, what can the practical manufacturer 
of vinegar learn from these theoretical explanations, it may be 
said there are many points of great importance for the execution 
of the work. The calculation of air shows that the alcohol 

* It is always supposed that the manufacture of vinegar is effected in 
generators used in the quick process. 



PRODUCTS OF ACETOUS FERMENTATION. 47 

requi res a Jarge suppl y } but the generators in general use in the 
quick process are by no means so arranged as to be adequate to 
ie^ theoretical demands. In fact it may be said that most of 
them allow~only a limited change of air and consequently work 
slower than they actually could. That the generators now in use 
are deficient is conclusively proved by the numerous constructions 
which have_ been proposed, especially in modern times, whose 
chief aim isjx) afford a free passage to the air. 

The fact that considerable heat is developed in the interior of 
the generator deserves consideration in connection with the heat- 
ing of the manufactory. If the temperature of the latter is so 
high as nearly to approach the optimum, i. e., the temperature 
most favorable for the formation of vinegar, it may easily happen 
that, in consequence of the vigorous oxidation of the alcohol, the 
temperature in the interior of the generators is increased to such 
an extent as to exceed this optimum, and the activity of the 
vinegar ferment would immediately diminish and even cease 
altogether. 

If, on the other hand, the temperature of the workroom is 
kept too low, the generators act sluggishly and do not produce as 
much as when the correct conditions are observed. But as by 
raising the temperature of the workroom the activity of the 
generators is increased, too low a temperature is less injurious to 
the regular course of the process than too high a one. 

The optimum of the formation of vinegar is at about 86 F., 
and hence the aim should be to maintain this temperature as 
nearly as possible in the interior of the generator. The temperature 
of the workroom must, however, be kept sufficiently low, so that 
the optimum in the interior of the generator cannot be exceeded. 

Another factor may here be mentioned. The closer the tem- 
perature in the interior of the generator approaches the optimum 
mid the quicker the supply of air, the more alcohol and acetic 
acid are lost by evaporation, or, in other words, the smaller the 
yield ofacetic acid. By the skillful utilization of conditions the 
manufacturer must aim to reduce this loss to a minimum, and 
this can be best effected by a suitable arrangement of the work- 
room. By regulating the change of air so that it is not greater 
than absolutely necessary, the air will soon become so saturated 



48 VINEGAR, CIDER, AND FRUIT-WINES. 

with vapors of alcohol and acetic acid that no further loss will 
take place until the renewing of the air in the workroom appears 
necessary. In which manner the manufacturer is to work in 
order to carry on the business most advantageously depends^ on 
the conditions of trade. If large orders have to be filled, he will 
endeavor to increase the capacity of the generators to the utmost 
by maintaining the optimum of temperature and a vigorous 
change of air in them, and in this case must submit to the in- 
creased losses inseparably connected with this high performance. 
If, on the other hand, he works for stock, he will not force the 
capacity of the generators to the utmost, but in order to work as 
cheaply as possible direct his attention to reduce the losses to a 
minimum. 

Yields of Acetic Acid obtained in the Practice. 

By keeping for some time an accurate account of the actual 
yields and comparing them with those theoretically obtainable, 
the former will be found to fall more or less short of the latter, 
and the difference will be the smaller the better the method of 
fabrication in use. 

In a vinegar factory occur many unavoidable losses, the 
sources of which have been indicated iu the preceding explana- 
tions ; alcohol and acetic acid evaporate, and besides a portion of 
them is entirely destroyed by too much oxidation. Now a Joss 
by evaporation, etc., of ten per cent, of the quantity of alcohol 
originally used must no doubt be considered a large one, but from 
numerous observations it may be asserted that even with the 
greatest care in working the loss in vinegar factories is not less 
than from 15 to 20 per cent., and may even be as much as 30 
per cent. 

These enormous losses of substance conclusively prove the de- 
fectiveness of the processes in general use and the urgent neces- 
sity for reformation. The experiments made for this purpose, 
and which have been especially directed towards a remodelling of 
the apparatus used, cannot be considered entirely satisfactory, 
though they were partially instituted by practical manufacturers, 
who, however, lacked the necessary theoretical education. 



PRODUCTS OF ACETOUS FERMENTATION. 49 

The principal requirement in our opinion is to provide the 
generator with a suitable ventilator, which will allow of the pas- 
sage through the generator of exactly the quantity of air required 
foTtEe conversion of the alcohol into acetic acid, and is so con- 
structed that the vapors of alcohol and acetic acid (or at least the 
larger portion) carried away by the current of air are condensed 
and thus regained. 

A vinegar generator has frequently been compared to a furnace, 
and in continuation of this comparison it may be said, that the 
construction generally used is a furnace lacking every arrange- 
ment for the regulation of combustion. In such a furnace as 
much fuel is burned as corresponds to the quantity of oxygen 
entering, while in a furnace of suitable construction the combus- 
tion of fuel can be accurately regulated by increasing or de- 
creasing at will the supply of air by means of a simple con- 
trivance. 

A vinegar generator of suitable construction should be provided 
with a similar arrangement. If the thermometer on the apparatus 
shows too low a temperature hence too slow a process of oxida- 
tion the course of the operation can in a short time be accel- 
erated by the production of a stronger current of air and the 
temperature correspondingly increased. If, on the other hand, 
oxidation proceeds too rapidly, which on account of the high 
temperature then prevailing in the apparatus is accompanied by 
considerable loss of substance, it can be quickly reduced to 
within the correct limits by decreasing the current of air. An 
apparatus unprovided with a ventilator is left more or less to 
itself, while one provided with such an arrangement is under the 
entire control of the manufacturer. 



50 VINEGAR. CIDER, AND FRUIT-WINES. 



CHAPTER V. 

METHODS OF FABRICATION OF VINEGAR. 

THE fabrication of vinegar from wine is undoubtedly the 
oldest and most simple method known, since it is only necessary 
to leave the wine to itself at a sufficiently high temperature to 
find it within a certain time converted into vinegar. A similar 
process takes place in all fermented fruit juices resembling wine. 

It would, therefore, seem proper to commence the description 
of the various methods of fabrication of vinegar with this simple 
process, but for reasons of an entirely practical nature it has 
been concluded not to do so. 

Since alcoholic fluids directly formed by the vinous fermenta- 
tion of sacchariferous plant juices possess the property of chang- 
ing under circumstances favorable to acetous fermentation into 
vinegar, it is evident that the latter can be prepared from them, 
and, in fact, it is possible to prepare it from all sweet fruits and 
parts of plants, such as cherries, strawberries, figs, bananas, etc., 
as well as from the juice of the sugar-cane, beet, chicory root, etc. 

Honey, which represents a concentrated solution of ferment- 
able sugar, as well as crystallized cane sugar, can likewise be in- 
directly used for the preparation of vinegar, since solutions of 
either can be brought into vinous fermentation and the resulting 
alcohol converted into acetic acid. 

By malting grain a peculiar body called diastase is formed, 
which possesses the property of converting starch into ferment- 
able sugar, and upon this fact is based the manufacture of beer 
and alcohol. In an indirect manner (the starch having to be 
converted first into sugar, and the latter into alcohol) it is, there- 
fore, possible to prepare vinegar from every substance containing 
starch, and for this reason we can speak of grain and malt 
vinegars. The beer prepared from the malt containing already 



METHODS OF FABRICATION OF VINEGAR. 51 

a certain quantity of alcohol can thus be directly converted into 
vinegar. 

Alcohol furnishing ultimately the material for the fabrication 
of vinegar, the direct use of dilute alcohol or spirit of wine for the 
manufacture of vinegar became obvious. By the employment of 
a suitable process, i. e., one corresponding to the 1 laws of acetous 
fermentation, it was found that the conversion of dilute alcohol 
into acetic acid could be effected in a much shorter time than by 
the old method, and upon this process is based the quick method 
of fabrication now in general use. A distinction may, therefore, 
be made between two principal methods of fabrication, viz., the 
older or slow process, which requires more time, and the more 
modern or quick process. 

In the old process many modifications are found, which are 
partially based upon old usage and partially upon the difference 
in the chemical composition of the raw material used. Beer, for 
instance, which contains only about 4 per cent, of alcohol and 
a large quantity of extractive substances (sugar, dextrin, salts, 
etc.), requires a different treatment from wine, which contains on 
an average 10 per cent, of alcohol, but scarcely 2 per cent, of 
extractive substances. Fruit-wines (cider, etc.), with only 5 to ft 
per cent, of alcohol but a large quantity of extractive substances, 
again require different treatment from grape wine, etc., so that, 
in a certain sense, it may be said there are as many different 
methods of fabricating vinegar as there are fundamental materials, 
and by taking into consideration the difference in the chemical 
composition of the latter, it is evident that there must be just as 
many varieties of vinegar. Besides acetic acid and a certain 
amount of water, every vinegar contains other substances, which, 
though frequently only present in very minute quantities, never- 
theless exert considerable influence upon its properties. 

Even vinegar obtained from dilute alcohol shows differences in 
odor, which depend on the material used in the preparation of 
the specific alcohol. Potato alcohol always contains traces of 
potato fusel oil (amyl alcohol), while certain fusel oils are found 
in alcohol prepared from grain or molasses. In the oxidation of 
the alcohol by the vinegar ferment these fusel oils are also oxi- 



52 VINEGAR, CIDER, AND FRUIT-WINES. 

dized and converted into combinations distinguished by their 
peculiar and very strong odor. 

Though these bodies occur in the vinegar in such minute quan- 
tities that they can scarcely be determined by chemical analysis, 
an expert can detect them by the sense of smell, and from the 
specific odor of the vinegar form a conclusive judgment as to the 
material used in its preparation. 

The differences in vinegar from wine, fruit, beer, and malt are 
still more prominent, and extend not only to the odor but also to 
the taste. Besides a specific odoriferous principle every wine 
contains oenanthic ether, tartar, tartaric and succinic acids, gly- 
cerin, and a series of extractive substances not thoroughly known. 
The odoriferous substances and the oenanthic ether also undergo 
alteration in the oxidation of alcohol, and are converted into 
other odoriferous combinations, with such a characteristic odor 
that wine vinegar can at once be recognized as such by it. On 
account of the presence of so many substances possessing a 
specific taste, that of the wine vinegar must, of course, differ 
from that of pure dilute acetic acid. 

Similar conditions prevail in fruit-wine, beer, malt-extract, etc., 
and hence vinegar prepared from these fluids must possess definite 
properties. 



CHAPTER VI. 

QUICK PROCESS OF FABRICATION OF VINEGAR. 

^\ 

IN 1823 Schutzenbach conceived the idea that by greatly en- 
larging the relative surfaces of contact of the alcoholic solution 
and air containing oxygen, the process of acetification would be 
greatly facilitated. His experiments proved successful, and soon 
after the quick vinegar process was generally adopted. Analo- 
gous processes were nearly at the same time invented, in Germany 
by Wagmann, and in England by Ham. 

The principle involved of course depends on an extreme 
division of the liquid being effected. This is very skilfully con- 



QUICK PROCESS OF FABRICATION OF VINEGAR. 53 

trivcd. By making the alcoholic solution percolate slowly 
through and diffuse over a mass of shavings, wooden blocks, 
pieces of coal or cork, etc., it forms a very thin layer, the surface 
of which is very extensive, and is therefore better adapted for 
the chemical appropriation of the oxygen in the current of air 
which is transmitted over it. The mass of shavings, etc., serves 
not only for the division of the liquid into fine drops but also as 
a carrier of the vinegar ferment. 

It will be readily understood that this arrangement presents in 
a high degree all the conditions required for the formation of 
vinegar : the vinegar ferment upon the shavings acquires from 
the liquid all the substances required for its maintenance and 
augmentation, and by the current of air passing through between 
the shavings is enabled to oxidize the alcohol to acetic acid. This 
process taking place simultaneously on thousands of points in a 
normally working generator explains why a large quantity of 
alcohol can in a comparatively short time be converted into 
acetic acid. The term quick process is hence very appropriate - 
for this method, it differing from the older slow process only in 
less time being required for its execution ; the chemical processes 
are the same in both cases. 

It will be seen that the generator, technically called " gradu- 
ator," used in the quick process may be compared to a furnace in 
which the fuel (in this case the alcoholic fluid) is introduced from 
above and the air from below. The spaces between the shavings, 
etc., may be compared to the interstices of a grate ; combustion 
takes place on the points of contact of the alcoholic fluid, vinegar 
ferment, and air. The product of (partial) combustion the 
vinegar collects in a reservoir in the lower part of the 
generator. 

Eachj^enerator, as previously stated, requires about 0.4 liter of 
air per second, which must ascend uniformly from below through 
tKeTnass of shavings, etc. At the first glance this would seem 
very simple, but its practical execution is accompanied by many 
difficulties, and hence a large number of various constructions of 
generators have been proposed by which this object is claimed to 
lie best attained. 



54 VINEGAR, CIDER, AND FRUIT-WINES. 

Arrangement of the Generators. 

A generator consists of a large vessel divided into three spaces 
above one another, the uppermost serving for the division of the 
alcoholic liquid into many small drops ; in the centre one, which 
forms the largest part of the apparatus, the alcoholic liquid is 
converted into vinegar, while the lower one serves for the collec- 
tion of the vinegar. 

The best form of the generator is that of a truncated cone. 
This form oifers to the alcoholic liquid in its passage from the 
upper part of the generator the opportunity of spreading over a 
constantly increasing surface, and by thus coming in contact with 
the fresh air entering the lower part of the apparatus its oxida- 
tion must evidently be promoted. The current of air in passing 
from below to above yields a certaiu portion of its oxygen in .the 
lower part of the apparatus, and if it were allowed to ascend in 
a vessel of a purely cylindrical shape, the alcoholic fluid running 
down would come in contact with air quite poor in oxygen. 
Hence this evil must be sought to be overcome by the accelera- 
tion of the motion of the air upwards, which is accomplished by 
giving the vessel the form of a slightly truncated cone. 

The generator, Fig. 3, consists of the vat Kof larch, fir, or other 
durable wood. The use of oak cannot be recommended, partially 
because of its being too expensive, and further on account of being 
so rich in extractive substances that a generator constructed of it 
has to be several times lixiviated with water before use, as other- 
wise the vinegar prepared in it would for a long time acquire a disa- 
greeable tang and dark color. In the upper portion of the vat is a 
perforated wooden disk S, and in the lower a false bottom of laths, 
the so-called lath-bottom L. The aperture A serves for the dis- 
charge of the fluid collecting underneath the lath-bottom. The 
cover D, the arrangement of which will be described later on, 
serves for regulating the draught of air in the generator. 

The hoops of the generators, as well as all other metallic parts 
in the factory, should IK? coated with good linseed-oil varnish or 
asphaltum lacquer, and care should be had immediately to repair 
any injury to this coating, as otherwise strong rusting is caused 



QUICK PROCESS OF FABRICATION OF VINEGAR. 



55 



by the vapors of acetic acid contained in the air of the work- 
room. 

In the lower portion of the generator, holes, 0, are bored. 
These holes are intended for the entrance of air, and in number 

Fig. 3. 




General Form of a Generator. 

may be as many as desired, since the regulation of the current of 
air is not to be effected on the lower portion of the apparatus, but 
on the cover. 

There is considerable variation in the dimensions of the gene- 
rators, some having only a height of 5 feet, with a lower diameter 
of 3 feet 3 inches, and others again a height of 20 feet or more, 
with a diameter of up to 6| feet. The small generators have 
the disadvantage of rapidly yielding heat to the exterior, and 
hence a correspondingly high temperature must be maintained in 
the workroom in order to keep up the proper degree of heat in 
their interior. On the other hand, generators of considerable 
height have the disadvantage of the shavings, etc., with which 
the centre space is filled, becoming strongly compressed by their 



56 VINEGAR, CIDER, AND FRUIT-WINES. 

1 / 

ownjweight, thus obstructing the proper passage of the air^ It 
has been sought to overcome this evil by placing several false 
lath-bottoms in the generator, in order to divide the weight of 
the filling into as many smaller weights as there are lath-bottoms. 
Bnt^ this arrangement is also attended with inconveniences^ jt 
being difficult to maintain a sufficiently strong draught^ofjairjLn^ 
generators of such height. 

Some manufacturers hold that the production of very strong 
vinegar containing 11 to 12 per cent, of acetic acid is only pos- 
sible in very tall generators. This opinion is, however, un- 
founded, the manufacture of very strong vinegar being just as 
well or rather better effected in small generators than in those 20 
feet or more high, which besides are very expensive. 

The manufacture of vinegar should be carried on in a room with 
a low ceiling, since even with the best heating arrangement .the 
temperature near the ceiling is always much higher than on the 
floor. However, with the use of generators 20 feet high the 
ceiling of the workroom must be at least 26 feet high, which 
makes it impossible to maintain a uniform temperature, as the 
difference between the upper and lower parts would frequently 
amount to more than 25. 

The most suitable generators are very likely those with a height 
not exceeding 10 feet, and a lower diameter of about 45 inches 
f^uud an upper one of about 35 inches. A large diameter, to be 
\ sure, contributes towards the maintenance of a uniform tempera- 
\ ture in the generator, but it has the disadvantage of making it 
1 difficult for the air to ascend uniformly through all parts of the 
filling. This evil is sought to be overcome by placing in the 
centre of the generator a tube open above and below and pro- 
vided on the sides with holes. Such tube, however, does not 
produce the intended favorable effect upon the draught of air in 
the parts of the filling surrounding it, experience having shown 
that the greater portion of the warm current of air ascending .in 
the interior takes the nearest road to the tc-p, i. e., through the 
tube, without passing sideways into the filling. Every generator 
of suitable construction should be provided with a well-fitting 
coyer. In this cover, Fig. 4, are bored in concentric circles holes 
which are intended for draught apertures. If the draught of air 



QUICK PROCESS OF FABRICATION OF VINEGAR. 



57 



in the interior is too great, it can be at once diminished by closing 
a number of these holes, it being even possible to direct it to- 
wards a certain portion of the filling. This arrangement is, 
however, only available when the false bottom to be described 

Fig. 4. 




Cover of a Generator provided with Draught Apertures. 

later on is either not used or provided with a number of short 
vertical tubes which permit the passage of the air. 

Many generators are provided with a number of obliquely 
bored apertures below the false bottom through which the air can 
escape. This is, however, attended with the disadvantage that 
a regular draught of air only takes place in the outer layers of 
filling next to the walls, while it is not sufficiently strong in the 
centre of the apparatus. It is also incorrect to have but one air 
aperture in the cover, which can be enlarged or diminished by 
means of a slide. In a generator thus arranged the current of 
air entering below will naturally pass chiefly through the conical 
portion of the filling, the basis of which is formed by the lower 
lath-bottom and the apex by the draught aperture in the cover. 
The lower portion of the filling, which embraces this cone, re- 
mains without sufficient ventilation and is ineffective as regards 
the oxidation of alcohol. 

In Figs. 5 and 6 the hatched surfaces terminated by the dotted 




58 



VINEGAR, CIDER, AND FRUIT- WINES. 



lines illustrate the portions of the generator in which, with the 
use of many apertures below the false bottom and a single one in 
the centre of the cover, the regular current of air from below to 



Fig. 5. 





Scheme of the Incorrect Conduction of Air in Vinegar Generators. 

above passes ; though a current of air takes place outside of these 
lines, it is in most cases too weak, and consequently the entire 
available space of the generator is not sufficiently utilized. 

The generators may also be entirely open below and stand in a 
shallow tub, which serves for the collection of the vinegar ; gen- 
erally, however, the lower portion of the generator itself is used 
for this purpose, and is provided with an arrangement for the 




Self-acting Discharge Arrangement on the lower part of the Generator. 



occasional discharge of the collected fluid. This can be effected 
either by a spigot fixed immediately above the bottom,. or, as in 



QUICK PROCESS OF FABRICATION OF VINEGAR. 



59 



Fig. 7, by a glass tube, which bends upwards nearly as high as 
the air-holes and then curves downward so as to discharge the 
liquid, when it rises as high as the shelf in the interior of the 
apparatus, into an appropriate vessel placed to receive it. Simple 
as this arrangement is, it is scarcely suitable in the practice on 
account of its being too liable to breakage, and hence it is better 
to provide the generator with an ordinary spigot, and prevent the 
vinegar from rising too high, by boring about J inch below the 
draught apertures a hole in which is fitted a pipe leading to a 
tub. The vinegar rising to the height of this pipe will commence 
to run off, and thus give warning to empty the generator by 
opening the spigot. 

In generators of older construction a strong hoop is fixed about 
one foot from the top, on which is placed a perforated disk which 
serves for distributing the alcoholic fluid as uniformly as possible 
over the entire filling. The disk, Fig. 8, is perforated with 
numerous holes (about 400 with a disk diameter of 3 feet) 




Disk of a Generator. 



arranged in concentric circles. These holes are loosely filled with 
cotton wick or packthread, a knot being made at the top end to 
keep them from falling through. The threads pass down to the 
shavings, and serve the double purpose of conducting the liquid 



60 VINEGAR, CIDER, AND FRUIT-WINES. 

equally through the body of the generator and also of stopping it 
from passing too rapidly through it (see Fig. 9). It is important to 
pack the disk so tightly against the walls of the generator that none 
of the liquid can percolate, which is best effected by a packing of 
tow and coating this with a mixture of equal parts of wax and 
colophony. The dripping of the alcoholic fluid through the disk 
taking place uniformly only when the latter lies perfectly hori- 
zontal, great care must be exercised in placing the generator. To 
prevent warping several strong cross pieces are inserted in the 
lower side of the disk. 

Fig. 9. 




Cross Section of the Disk. 

As previously mentioned the current of air must pass through 
all portions of the filling, and for this purpose seven short glass 
tubes, r (Fig. 8), about J inch in diameter, are inserted in the disk. 
These tubes are so arranged that one is in the centre of the disk 
and the others in a circle equidistant from the centre and the 
periphery. Upon the disk is placed the well-fitting cover, pro- 
vided with an aperture for the passage of the air. This aperture, 
about 3 inches square, is provided with a well-fitting slide, so 
that it can be made larger or smaller at will. As previously 
stated, it is more suitable to provide the cover with a large 
number of draught holes arranged in concentric circles and to fit 
each hole with a wooden stopper. By withdrawing or inserting 
the stoppers the draught of air can then be properly regulated. 

To effect the influx of air from below in such a manner that it 
not only takes place through the draught holes in the circumfer- 
ence, but also insures its conveyance to the centre of the appa- 
ratus, it is recommended to insert in the centre of the lower part 
in which the fluid collects a tube, R, Fig. 10, which is open at 
both ends and protected above by the hood H against the drop- 
ping in of alcoholic liquid. 




QUICK PROCESS OF FABRICATION OF VINEGAR. 



61 



A uniform distribution of the alcoholic liquid upon all portions 
of the filling of the apparatus would be effected if about the same 
quantity of liquid dripped from all the threads. This being, how- 
ever, difficult to attain, it has been sought to give the disk a more 

Fig. 10. 




Generator with Air-tube in the Lower Portion. 

suitable arrangement, which consists, for instance, in the insertion 
of small wooden tubes with a small aperture on the side (Fig. 11). 
This arrangement, though very suitable in itself, becomes, however, 
useless in case of the slightest warping of the disk, a number of 
the tubes being then raised so high that no fluid runs through 
them while it passes in a full stream through the others. 

Fie. 11. 




Disk with Wooden Tubes. 



These evils connected with the use of a disk can be somewhat 
diminished by the employment of a so-called "tilting trough" 
(Figs. 12 and 13), which is arranged as follows : 



62 VINEGAR, CIDER, AND FRUIT-WINES. 

Upon a perfectly horizontal axis is placed a rotatory, trough- 
like vessel divided by a partition into two equal parts. 

If the tilting trough is in the position shown in Fig. 12 the 
alcoholic liquid runs through the cock, placed above, into the 
partition marked 1. 



Fig. 12. 



Fig. 13. 




Tilting Trough. 

As soon as this partition is filled to a certain height it turns 
over in consequence of the disturbance of the equilibrium of the 
trough and assumes the position shown in Fig. 13. In this posi- 
tion partition 2 is gradually filled with alcoholic liquid, the trough 
then tilts back into position 1, and so on. 

It will be seen that with the assistance of such a tilting-trough 
the same quantities of liquid can always be poured out at certain 
intervals, and that this arrangement can be used for distributing 
the alcoholic liquid upon the disk, the latter in this case being 
best provided with holes having the form of an inverted cone. 
The apex of this cone forms a very narrow aperture through 
which the alcoholic liquid poured upon the disk trickles in very 
thin jets upon the filling of the generator. 

But even this arrangement is not free from objections ; it works 
entirely satisfactorily only as long as the disk remains in a per- 
fectly horizontal position. In the more modern constructions of 
vinegar generators the disk is generally entirely omitted and the 
distribution of the alcoholic liquor effected by a so-called "spar- 
ger," similar to the one used in beer brewing for sprinkling malt 
residues. The sparger is arranged like a simple turbine, and is 
moved by reaction in the direction opposite to that in which 
the discharge of the fluid takes place. Spargers used in vinegar 



3 



QUICK PROCESS OF FABRICATION OF VINEGAR. 63 

factories can be constructed only of a material indifferent to the 
action of acetic acid, such as wood, glass, hard rubber, etc. Their 
construction will be understood from Figs. 14 and 15. 

Fig. 14. 



Sparger (view from above). 

Into a hollow cylinder of wood are screwed four thin wooden 
tubes, closed at both ends and perforated lengthwise with nume- 
rous small holes ; the tubes are so arranged that all the holes are 

Fig. 15. 




Sparger (cross-section). 

directed towards one side. The basin in the centre is closed on 
top by a glass tube about 20 inches long and of sufficient width 
to allow of the passage of as much fluid as can at one time run 
off through all the lateral tubes. 



64 



VINEGAR, CIDER, AND FRUIT-WINES. 



The principal requisite of the correct working of the sparger is 
that it revolves with ease around its vertical axis. This is effected 
by placing in the centre of the vessel a glass pin drawn out to a 
fine point and running in a small glass step ; the vertical glass 
tube is guided in a sharp-edged wooden ring fastened to a stay 
placed upon the cover of the generator (Fig. 16). The sparger 
finds its centre of motion upon a lath inserted in the direction of 
the diameter of the generator. This lath is placed at such a height 
that the sparger can move freely between it and the cover of the 
generator. The sparger being in position as shown in Fig. 16, a 
funnel-form vessel, through which the alcoholic fluid is poured in, 
is placed upon the glass tube. 




Sparger placed in the Generator. 

^ By now pouring through this funnel-form vessel the alcoholic 
liquid in a sufficiently strong stream, so that during its influx the 
glass tube remains filled, it passes in fine jets through the lateral 
openings, and, the sparger revolving in an opposite direction, is 
distributed in the form of a fine spray over the filling in the gene- 
rator. 

The use of the sparger overcomes the difficulties frequently 
occurring with the disk, especially as regards the position of the 
latter, and the circulation of air through the apparatus also takes 




Q 

QUICK PROCESS OF FABRICATION OF VINEGAR. 65 

place in a perfectly uniform manner. A number of apertures in 
the cover of the generator serve also here for the regulation of 
the current of air. 

A thermometer is an indispensable adjunct to a generator, and 
should be so placed that the temperature prevailing in the appa- 
ratus, and especially in the centre, can be readily read off. This 
is best effected by introducing at about half the height of the 
apparatus, through an obliquely bored hole in one of the staves, 
a glass tube closed at the lower end and reaching to the centre of 
the filling. This tube serves for the reception of a thermometer 
fastened to the lower end of a stick of wood. The latter pro- 
jects from the glass tube, so that the thermometer can be quickly 
drawn out and the temperature read off. 

Fitting of the Generators. 

For filling the space between the upper disk and lower lath 
bottom, material offering a large surface for the distribution of 
the alcoholic liquid is used. Pieces of charcoal and of pumice 
stone, washed in hydrochloric acid and well rinsed in water to 
remove empyreumatic substances, which would render induction 
of acetous fermentation impossible, have been used for the pur- 
pose, as well as old corks or waste of cork. Pumice stone 
especially has the advantage of being easily cleansed by water 
and by fire when the liquors, such as those from fruits, contain a 
great deal of mucilaginous and albuminous substances, which 
will rapidly accumulate and prevent the proper working of 
shavings. Grape-stalks, which actually present a very large 
surface, were formerly much used for filling the generators, but, 
independently of the fact that they cannot be everywhere obtained 
in sufficient quantities, they have the disadvantage of becoming 
in a short time so strongly compressed as to prevent the free pas- 
sage of air. 

J3ut beechwood shavings are now nearly everywhere employed 
for filling the generators. Indeed, beechwood presents many ad- 
vantages; it can be had easily and cheap; it curls well and 
stands without breaking for a length of time. White woods will 
curl as well, but they will hot stand so well as beech ; resinous 
5 



66 VINEGAR, CIDER, AND FRUIT- WINES. 

woods are not porous enough, and besides their resin is objection- 
able, as it may partly dissolve in the vinegar ; oak wood does not 
curl as well and contains too much coloring matter and tannin. 

The beech shavings are generally made in special factories. 
They consist of wooden bands about J millimeter (0.02 inch) 
thick, 4 centimeters (1.57 inches) wide, and 40 to 50 centimeters 
(15.74 to 19.68 inches) long. They are rolled into close spirals 
by a special machine, and each shaving, according to the above 
dimensions, presents a surface of about 400 square centimeters (62 
square inches). Now, as a generator of moderate size contains many 
thousands of such shavings, it will be readily seen that the sur- 
face over which the alcoholic fluid is distributed is an extraordi- 
narily large one. 

A shaving of the stated dimensions represents in a rolled state 
a cylinder with a volume in round numbers of 28 cubic centi- 
meters (1.7 cubic inches). By allowing an interspace of 14 
cubic centimeters (.85 cubic inch) between the shavings, 28 + 14 
= 42 cubic centimeters (1.7 + 0.85=1.92 cubic inches), space is 
required for each shaving. The space to be filled with shavings 
in a generator 1 meter (3.28 feet) in diameter and 2 meters 
(6.56 feet) high is equal to 1.57 cubic meters (55.44 cubic feet), 
and hence 58,000 shavings, with a total surface of 2112 square 
meters (22,733.56 square feet), are required for the purpose. 
Now suppose only 5 per cent, of this surface is continually active 
in the formation of vinegar, we have still a surface of over 100 
square meters (1076.43 square feet) at our disposal. But the ac- 
tive surface would seem to be actually much smaller even with 
the most favorable working of the generator, as otherwise the 
average quantity of alcohol daily converted into acetic acid in a 
generator would be much larger than is actually the case. 

Beechwood shavings contain a considerable quantity of ex- 
tractive substances, which if not removed would for a long time 
impart a disagreeable tang (woody taste) to the vinegar. Hence 
it is recommended to lixiviate the shavings in water repeatedly 
renewed, in order to get rid of the substances soluble in cold 
water and remove the last traces by treatment with steam. 

This steaming is best effected in a large tub or a vat, which is 
later on to be used as a generator. The shavings are thrown in 



QUICK PROCESS OF FABRICATION OF VINEGAR. 67 

loosely and covered with a loaded lid. A steam-pipe is intro- 
duced through a hole near the lid and the tap-hole near the 
bottom is opened. The steam-pipe being connected with a boiler, 
in which prevails a tension of If to 2 atmospheres, the steam- 
cock is at first opened but slightly, to prevent the steam entering 
with great force, from throwing off the lid, or even bursting the 
vessel. In the commencement of the operation the steam con- 
denses on the shavings, but after some time the vessel becomes 
very hot, and a dark-colored fluid, consisting of almost boiling 
water charged with extractive substances of the wood, begins to 
run off. After continuous steaming for about 20 to 60 minutes 
according to the size of the vessel the fluid running off be- 
comes clearer until finally clear water is discharged, which is in- 
dicative of the removal of the extractive substances soluble in 
water. 

Although not absolutely necessary it is advisable to dry the 
steamed shavings. When air-dried they still contain about 20 
per cent, of water, which in the subsequent " acidulation" of the 
generator must be replaced by vinegar. Hence it is recommended 
to dry the shavings completely by exposing them for some time 
to a current of air of 194 to 212 F. 

In a factory provided with a central heating apparatus* in the 
cellar, this drying of the shavings can be effected without diffi- 
culty, it only being necessary to put them in a vessel with a per- 
forated bottom and open on top, and place the vessel over an 
aperture of the channel through which the hot air from the heat- 
ing apparatus ascends, closing all other apertures. 

Entirely dry wood absorbing with avidity moisture from the 
atmosphere, the shavings thus dried should immediately be 
brought into another vessel and, while still hot, moistened with 
the vinegar intended for acidulation. 

Before using the shavings for filling the generators it is neces- 
sary to allow them to swell by placing them in water or alcoholic 
liquid. If this were omitted and the shavings introduced in a 

* The arrangement of a central heating apparatus will be described later 
on in speaking of the arrangement of the factory. 



68 VINEGAR, CIDER, AND FRUIT- WINES. 

dry state they would rise above the generators as soon as moist- 
ened, on account of the increase in volume by swelling. 

In most factories it is customary simply to pour the shavings 
into the generator, but for a uniform distribution of the alcoholic 
fluid it is advisable to proceed with the filling in a certain order. 
First place the shavings in three or four regular layers upon the 
lath-bottom, then pour them in loosely to a height of 8 to 12 
inches, and after levelling the surface as much as possible pour in 
again, and continue in this manner until the generator is filled ; 
the uppermost portion should again consist of three or four regu- 
lar layers. 

All the generators used in a vinegar factory should be of the 
same size and charged with the same number of shavings, which 
is best effected by filling them with the same quantity by weight. 
The total surface of shavings being thus nearly the same in all 
generators, the latter will work uniformly, i. <?., with an equal 
temperature and draught of air ; and in the same time convert 
equally large quantities of alcohol into acetic acid. 



CHAPTER VII. 

ARRANGEMENT OF A VINEGAR FACTORY. 

THE arrangement of the manufacturing rooms formerly custo- 
mary even in large factories is by no means a suitable one. The 
generators were generally simply placed in a room adapted for the 
purpose by its size, while the high temperature required was 
sought to be maintained by heating. By considering, however, 
that every considerable variation in the temperature causes also a 
disturbance in the formation of vinegar, it will be seen that the 
object of keeping up an undisturbed working of the factory can- 
not be attained by such primitive means. A suitable arrange- 
ment of the room in which the vinegar is to be manufactured is, 
therefore, absolutely necessary. 

The principal requisites to be observed are : the maintenance 
of a uniform temperature in the room and a suitable arrangement 



ARRANGEMENT OF A VINEGAR FACTORY. 69 

for ventilation. Further, simple means for the conveyance of 
the raw materials and the finished product must be provided for 
and means devised for regaining the acetic acid, with the vapors of 
which the air in the manufacturing room is constantly saturated. 

For the maintenance of a uniform temperature in the work- 
room, which should remain almost constant even in the coldest 
season of the year and during abrupt changes in the outer tem- 
perature, the walls should be of more than ordinary thickness 
and the number of windows and doors sufficient only for the 
necessary light and communication, and so arranged that 110 un- 
intentional ventilation can occur. The windows and doors 
should, therefore, be double, and the latter so placed that one can 
be closed without opening the other. The walls and ceilings should 
be plastered and preferably papered with stout packing paper. 

Asphaltum, being impermeable and also indifferent to the ac- 
tion of acetic acid, is undoubtedly the best material for the floor 
of the workroom, though it may also be constructed of large 
slabs of sandstone with the joints filled in with asphaltum. 
Cement floors can only be recommended provided they are im- 
mediately after their construction coated with water-glass until 
they cease to absorb it. In constructing the floor care must be 
had to give it such an inclination that the entire surface can be 
cleansed by a simple jet of water. If the heating channel is 
conducted lengthwise through the workroom, gutters for the 
rinsing water to run off must be arranged on both sides. 

The height of the room depends on that of the generators. 

Heating of the Workroom. 

Heating by a stove placed in the workroom itself can only bo 
recommended for very small factories ; in larger ones a special 
heating apparatus should always be provided. Where stoves 
are used it is recommended to arrange them so that the fuel can 
be supplied and the ashes removed from the outside, i. e., from a 
room adjoining the actual workroom. In attending to the stoves 
fine particles of ashes will unavoidably reach the air ; from the 
latter they may get into the generators, and being soluble in 
acetic acid may injure the vinegar ferment. 

For large factories a heating apparatus similar to the one shown 



70 



VINEGAR, CIDER, AND FRUIT-WINES. 



in Figs. 17 and 18 can be recommended. The iron heating cyl- 
inder, which is provided with the feeding-door H and the air- 
regulating door A, stands in a vault beneath the centre of the 
room to be heated. It is surrounded on all sides by the sheet- 
iron jacket J/, reaching from the floor of the cellar to the top of 
the vault. In the vault is a circular aperture, 0, for the reception 
of the channels C and <7 r The latter, ascending slightly, run 



Figs. 17,18. 



P P 




Ground-plan and Elevation of Heating Apparatus. 

along the centre of the room to be heated. Above they are cov- 
ered by cast-iron plates, P, and by pushing these plates apart or 
substituting a lattice plate for one of them in any part of the 
channel, warm air can be admitted to the room. If the room is 
to be heated without renewing the air, the register in the flue L 
which communicates by a flat iron pipe with the lower part of 



ARRANGEMENT OF A VINEGAR FACTORY. 



71 



*. 19. 




1L-55 



the jacket, is opened. The furnace being heated the air in the 
room is sucked in the direction of the arrow through the flue L, 
and passing between the jacket and the furnace, ascends strongly 
heated through and penetrates through the openings in the 
channel ; air is again sucked through L, and so on. 

If, however, the air in the workroom is to be entirely renewed, 
the air-flue L is closed and a register (not shown in the illustra- 
tion) in the lower part of the jacket opened. 
In this case the air in the cellar is sucked in, 
heated and distributed through the channels 
C and C v By partially opening this register 
and that in L a portion of the air can be re- 
newed at will. 

In order to be able to form a correct idea 
of the state of the temperature prevailing in 
the room, it is advisable to have several or- 
dinary thermometers and also a maximum 
and minimum thermometer. If the latter 
show r s no greater variation than from 4 to 
5, the process of heating may be considered 
as satisfactory. 

A very suitable apparatus for controlling 
the temperature in a vinegar factory is au 
electrical thermometer, which is so arranged 
that a bell rings in case the temperature rises 
above or falls below a certain degree. By 
placing two such thermometers in the room, 
the bell of the one indicates the rise of the 
temperature above the limit, and that of the 
other that it has fallen below it. 

Fig. 19 illustrates the principle of a maxi- 
mum electrical thermometer, i. e.> one which 
rings a bell when the temperature of the room 
exceeds a certain limit. Into the bulb of an 

Maximum Electrical 

ordinary mercury thermometer is melted a Thermometer, 
platinum wire ; another platinum wire is in- 
serted in the tube up to the mark indicating the temperature not 
to be exceeded, for instance, 35 C. The ends of the platinum 



-35 



=-30 



=-20 



=-15 




72 VINEGAR, CIDER, AND FRUIT- WINES. 

wires projecting from the thermometer are connected by insulated 
copper wires with a galvanic battery consisting of several ele- 
ments, an ordinary door-bell being inserted in one part of the 
conductor. If, now, in consequence of a continued increase in 
the temperature, the mercury rises to the point of the platinum 
wire at the figure 35, the circuit of the battery is closed at the 
same time by the column of mercury, and the bell rings and 
keeps ringing until the circuit is again opened by the mercury 
falling below 35. 

The minimum electrical thermometer, used for indicating the 
falling of the temperature below a certain degree, is so arranged 
that one platinum wire is melted into the bulb of the ther- 
mometer and the other in the tube at the point below which the 
temperature is not to fall. As long as the mercury remains above 
this point a battery, which changes a piece of iron to an electro- 
magnet, whose anchor opens a second battery which is connected 
with an electric bell, remains closed. .If the temperature falls 
below the minimum, the circuit of the first battery is opened, and 
the anchor of the electro-magnet falling down eifects the closing 
of the second battery and sets the bell ringing. 

By placing such thermometers not only in the working room 
but also in every generator, the control of the entire process 
would be immensely facilitated, but at the present time these 
useful and at the same time inexpensive instruments are but little 
used in vinegar factories. 

In factories arranged according to the automatic system, the 
alcoholic liquid is contained in vessels placed at such a level that 
their contents can run directly into the generators. The alcoholic 
liquid having to be correspondingly heated, adequate provision 
must be made for heating the space in which the reservoirs are 
placed. In order not to increase the height of the entire room, it 
is recommended to place these vessels in the centre and give only 
to this portion the required height. This has the further advan- 
tage that the pumping up of the alcoholic liquid can be effected 
by the use of a pump with a short rising-pipe, and the liquid can 
be readily conducted from the reservoirs to the separate generators 
by means of pipes. 



ARTIFICIAL VENTILATION OF VINEGAR GENERATORS. 73 



CHAPTER VIII. 

ARTIFICIAL VENTILATION OF THE VINEGAR GENERATORS. 

THE first experiments in conveying direct air to every gene- 
rator were made in England ; but though this step towards 
improvement in the fabrication of vinegar must be considered 
an important advance, the English process failed of being ac- 
cepted in practice on account of the inadequacy of the apparatus 
used. 

In the English factories by a special apparatus a current of air 
was sucked from above to below through every generator. As 
shown in Fig. 20, the tall generators are open on top and 
divided by false bottoms, upon which the shavings, etc., rest, into 
several partitions ; above each false bottom holes are bored in the 
circumference of the generators. In the bottom of the generator 
is inserted a pipe which is connected with an arrangement for 
sucking in the air, a blower or air-pump being used for the 
purpose. 

As will be seen from the illustration, the suction of air through 
all parts of the generator cannot be uniformly effected by the use 
of this apparatus, the current of air being much more checked 
in the upper portions, by the false bottoms and holes in the 
circumference, than in the lower. Hence the effect of the air- 
pump or blower will chiefly assert itself in the lowest partition. 
This evil might be remedied by leaving out the false bottoms 
and placing no air-holes in the circumference of the generator 
entirely open at the top ; by these means the air would be forced 
to pass in a uniform current through the entire layer of the filling 
material. 

That the passage of the current of air from above to below is 
entirely incorrect, because contrary to all theoretical requirements, 
can be readily explained : In a generator in full activity, oxida- 
tion of alcohol must already take place in the uppermost portion, 



74 



VINEGAR, CIDER, AND FRUIT-WINES. 



air. 



Fig. 20. 



and hence a certain quantity of oxygen is withdrawn from the 
This process being also continued in the lower parts of the 
generator, a current of air already 
deprived of a portion of its oxygen, 
and hence less suitable for the fur- 
ther formation of acetic acid, would 
be sucked in the same direction 
which the drops of alcohol take. 

The principal reason advanced 
for the use of a current of air from 
above to below is that by these 
means a uniform temperature is 
maintained in all parts of the gen- 
erators, while it rises considerably 
in the upper part of those in which 
the air passes from below to above. 
This rise of temperature is, how- 
ever, agreeable to nature. The air 
entering from below oxidizes the 
alcohol to acetic acid, becoming 
thereby poorer in oxygen and again 
heated. By the higher temperature 
it acquires, it is, however, capable 
of a more vigorous chemical activity, 
so that it will induce the process of 
the formation of vinegar, even in 
the uppermost portions of the gen- 
erator. Besides, the warmer cur- 
rent of air moving upwards has the 
further advantage of yielding heat 

to the drops of alcoholic fluid trickling down. With the use oi 
generators of moderate height, and with a suitable regulation ot 
the draught of air, the maximum temperature will not be ex- 
ceeded, even in the uppermost portions of the generator. 

If no rise of temperature is observed in the lower portions of 
a generator in which the air passes from above to below, it only 
proves that the air has lost too much oxygen to further effect a 
vigorous oxidation of the alcohol. It will be readily understood 




Generator with Ventilation from 
above to below. 



ARTIFICIAL VENTILATION OF VINEGAR GENERATORS. 75 

that under these conditions a diminution in the loss of substance 
can, to a certain degree, be effected, but it is doubtful whether 
the generators are utilized in the manner they should be ; besides, 
the diminution in loss of substance cannot be very considerable. 
Since a high temperature also prevails in ventilated generators, 
the current of air passing downward will be loaded with as much 
vapor of alcohol or of acetic acid as it can absorb at this tempera- 
ture, and, hence, it would seem no diminution in loss by evapora- 
tion could be effected. To render this possible, the current of 
air sucked from the generator would have to be sufficiently cooled 
off by a suitable arrangement for the greater portion of .the 
vapors carried away by the current of air to condense to a fluid. 

Schulze's Ventilating Apparatus. 

The ventilation of the vinegar generators, according to the 
above-described method, requires the presence of an uninterrupt- 
edly acting power for working the air-pump, blower, etc. As is 
well known, a current of air can, however, be also produced by 
heating the air passing through an ascending pipe, by which it 
becomes specifically lighter and ascends, while denser air enters 
from below, etc. Schulze, as will be seen from Fig. 21, has 
applied this method to the ventilation of vinegar generators. 

Schulze's generator differs somewhat from the ordinary con- 
struction, and is arranged as follows : The vat has a height of 
about 8 feet, and a diameter of 2 feet 6 inches. In the upper part 
it is terminated by a false bottom, fitting air-tight, and is further 
provided with a cover, in the centre of which is an aperture about 
2J inches in diameter, which serves for the entrance of air, while 
another aperture on the side serves for pouring in the alcoholic 
liquid. In the false bottom are inserted four glass-tubes, open 
at both ends and about f inch in diameter, which afford a passage 
to the air. The generator is filled with pieces of washed and 
assorted charcoal, so that pieces of the size of a nut are placed 
upon the lath-bottom, and upon this are poured smaller pieces, 
gradually decreasing in size until those on the top are only that 
of a pea. In the centre of the bottom is inserted a wooden tube, 
open at both ends and provided -on top with a hood to prevent 



76 



VINEGAR, CIDER, AND FRUIT- WINES. 



the trickling in of vinegar (see Fig. 10). By a suitable inter- 
mediate piece, this tube is connected with the draught-pipe (see 
Fig. 21), in which the ascension of the air by heating is effected. 

Fig. 21. 




^^5^^^^^^^^^^^^^^^5^5s> 

1 '"1 i i I 1 

Schulze's Ventilating Apparatus. 

The draught-pipes are of cast iron, and are about J-inch thick 
and about 4^ feet long, with a clear diameter of 2 inches. They 
are placed, strongly inclined, over the flues of a heating appara- 
tus and covered above by a double course of stone. The air in 
the iron draught-pipes, being heated by the escaping gases of 
combustion, ascends and effects the passage of a current of air 
from above to below in the generators. For keeping up a con- 
stant ventilation it is claimed to be sufficient to heat the furnace 
only once a day. With this construction it is necessary to have 
as many draught-pipes as there are generators; the same effect 
might, however, also be attained by connecting the pipes leading 
from several generators with a draught-pipe of a somewhat greater 
diameter and length. 

It is not difficult to prove that a uniform ventilation of the 
generators cannot be obtained by the use of this construction. 
As long as the draught-pipes are strongly heated, a very rapid 
current of air will pass through them and the generators con- 



ARTIFICIAL VENTILATION OF VINEGAR GENERATORS. 77 

nected with them, which will, however, decrease in the same 
degree as the pipes cool off. Hence, in the first case, a too rapid 
current of air accompanied by a correspondingly strong evapora- 
tion of alcohol would pass through the generators, and in the 
latter, ventilation would be so sluggish that the process of the 
formation of vinegar would not proceed in a normal manner. 

Generators with constant Ventilation and Condensation. 

The object to be attained by the use of special ventilating con- 
trivances is a double one : to conduct a constant current of air 
through the generators, and, further, not to allow the temperature 
to rise above a certain limit, so as to decrease by these means the 
loss by evaporation of alcohol and acetic acid. This object can, 
however, be attained only by the use of an apparatus which 
allows of the most accurate regulation of the current of air pass- 
ing through the generator, and is connected with a contrivance 
by which the vapors of alcohol and acetic acid carried along by 
the current of air can be condensed as much as possible. The 
following apparatus is well adapted for the purpose ; its principal 
parts consist of the generator, the apparatus for condensing the 
vapors, and the ventilator. 

The construction of the lower part of the generator, Fig. 22, 
is the same as of those previously described ; the cover fits tightly 
upon the upper edge of the vat, the joint being made air-tight by 
strips of paper pasted over it. In the centre of the cover is a 
square aperture, from which rises a quadrangular pyramid, P, 
constructed of boards, upon which sits a low prism, A. The 
sparger D has its centre of motion upon the lath L, placed in 
the uppermost portion of the generator, and is guided above in 
the short lath L v which carries the sharp-edged ring described 
on p. 64. E is the glass tube through which the alcoholic liquid 
flows into the funnel of the sparger. On the point where the 
pyramid passes into the prism A, is a bottom provided with a 
circular aperture, 0, 2J to 3 inches in diameter. Upon the top 
of the prism A is placed a nut, in which runs a wooden screw, 
provided on the lower end with a wooden disk, S, of a somewhat 
greater diameter than the aperture 0. By raising or lowering 



78 VINEGAR, CIDER, AND FRUIT-WINES. 

this screw, the aperture can be closed more or less or entirely, 
and thus the strength of the current of air regulated at will in 
every generator. The prisms A of all the generators are con- 
nected with each other by the conduit R, constructed of boards. 



Fig. 22. 



Fig. 23. 




Ventilating Apparatus according to Bersch. 

This conduit R is connected best in the centre between an 
equally large number of generators with the condensing appa- 
ratus, the chief feature of which is a worm similar to that used in 
a still. Fig. 24 shows the apparatus in cross-section. 

In a sheet-iron vessel of the same height as the generator is 
placed another vessel, so that there is a distance of about 5f 
inches between the walls. From a reservoir situated at a higher 
level cold water runs into the apparatus through the pipe K, and 
off through the short pipe W. In the space between the walls of 
the two vessels lies a tin coil with very thin walls and a diameter 
of at least 2J inches. On top this tin coil is connected with the 
wooden tube R (Fig. 23) and below with the iron pipe R r which 
leads to the ventilating apparatus. C is a glass tube about 16 
inches long and J to f inch in diameter, which reaches nearly to 
the bottom of the flask half filled with water. 

The ventilating apparatus consists of an ordinary Meidinger 
self-regulating stove, but its jacket is closed below so that air can 
only pass in between the heating cylinder and the jacket through 
the pipe R v coming from the condensing apparatus. 



ARTIFICIAL VENTILATION OF VINEGAR GENERATORS. 79 

The apparatus works as follows : According as combustion 
in the stove proceeds slowly or quickly by the corresponding 
position of the regulating register, the air between the heating 
cylinder and the jacket becomes less or more heated and ascends 

Fig. 24. 



W 




Condensing Apparatus Cross Section. 

with corresponding velocity. But as the further entrance of air 
can take place only through the pipe R ly the tin coil, and the 
wooden tube R, a uniform current of air from below to above 
must pass through all the generators. To regulate the strength of 
the current for each generator, it is only necessary to close the aper- 
ture (Fig. 22) more or less by raising or lowering the screw. 

The current of air passing from the wooden tube R into 
the tin coil carries with it the total amount of evaporated alcohol 
or acetic acid. By passing through the tin coil, which is cooled 
by the water, the air itself becomes cooled off, and the greater 



80 VINEGAR, CIDER, AND FRUIT-WINES. 

portion of the vapors held by it condense to liquid and run off 
through the tube C into the bottle. The fluid thus obtained con- 
sists chiefly of alcohol, water, and acetic acid, and is again used 
for the preparation of alcoholic liquid. On account of the pecu- 
liar form of the cooling vessel but little water is required for 
feeding it. As the quantity of vapor separated from the air 
will, however, be the greater the more energetically the tin coil is 
cooled off, it is recommended to reduce the temperature of the 
water to nearly 32 F. by throwing in pieces of ice. 

It has been proposed to regain the vapors by conducting the 
air containing them into a large vessel in which water in the 
form of a fine spray trickles down or is injected. It is, of course, 
possible in this manner to condense the greater portion of vapors 
of a higher temperature and tension, but with vapors of at the 
utmost 95 F. little success would be attained. The greater 
portion of the vapors remaining uncondensed a very large quan- 
tity of fluid containing but little alcohol would be obtained in 
the course of a day and this fluid could at the best be used only 
instead of water for the preparation of alcoholic liquid. The 
value of the material thus regained would not cover the working 
expenses of the apparatus. By working, however, with the con- 
densing apparatus described above, the condensed alcohol does 
not even contain the total quantity of water evaporated with it, 
and it need only be compounded with the corresponding quantity 
of water and vinegar again to yield alcoholic liquid. 



CHAPTER IX. 

AUTOMATIC VINEGAR APPARATUS. 

THE principal work to be performed in a vinegar factory con- 
sists in pouring at stated intervals the alcoholic fluid into the 
generators. In a large factory several workmen are constantly 
engaged in this work and losses by spilling are unavoidable. 
Further it is almost next to impossible always to pour in the 
same quantity at exactly the same intervals, and sometimes a 



AUTOMATIC VINEGAR APPARATUS. 81 

generator may even be entirely overlooked and thus remain inac- 
tive until the next supply of alcoholic liquid is poured in. 

The greatest disadvantage is, however, the interruption for 
several hours daily of the formation of vinegar in all the genera- 
tors, so that, for instance, in a factory working 16 hours a day, 
one-third of the time is lost. Independently of the small return 
on the capital invested, these interruptions are accompanied by 
many other conditions injurious to the regular running of the 
factory. 

The greatest of these evils is that with the cessation of the sup- 
ply of alcoholic fluid the augmentation of the vinegar ferment 
diminishes and finally ceases altogether. Further, the develop- 
ment of heat in the interior of the apparatus at the same time 
ceases and the temperature is reduced several degrees, this phenom- 
enon appearing even in factories provided with the best heating 
apparatus and keeping up a constant temperature in the workroom 
during the night. 

In the morning when work is resumed, it is in most cases 
necessary to vigorously air the apparatus by opening all the draught 
holes in order to gradually restore the temperature to the required 
degree, and it requires some time before the apparatus again 
works in a normal manner. 

The vinegar ferment, however, is very sensitive to changes of 
temperature as Avell as to the concentration of the nourishing 
substance surrounding it, and there can be no doubt that its aug- 
mentation is prejudiced by the continuous variations of tempera- 
ture to which it is exposed during the interruptions of several 
hours a day. That such is actually the case is shown by the fact 
that the quantity of vinegar ferment formed in the generators is 
small as compared with that which under conditions favorable to 
the ferment forms in a short time upon alcoholic liquids. 

Besides the debilitation of the vinegar ferment and the conse- 
quent disturbance in the regular working of the factory, the 
repeated reduction of the temperature in the generators has the 
further disadvantage that besides the vinegar ferment other fer- 
ments for whose development a low temperature is more favorable 
may be formed, and these ferments may increase to such an extent 
as to entirely suppress the vinegar ferment. There can scarcely 
6 



80 VINEGAR, CIDER, AND FRUIT- WINES. 

portion of the vapors held by it condense to liquid and run off 
through the tube C into the bottle. The fluid thus obtained con- 
sists chiefly of alcohol, water, and acetic acid, and is again used 
for the preparation of alcoholic liquid. On account of the pecu- 
liar form of the cooling vessel but little water is required for 
feeding it. As the quantity of vapor separated from the air 
will, however, be the greater the more energetically the tin coil is 
cooled off, it is recommended to reduce the temperature of the 
water to nearly 32 F. by throwing in pieces of ice. 

It has been proposed to regain the vapors by conducting the 
air containing them into a large vessel in Avhich water in the 
form of a fine spray trickles down or is injected. It is, of course, 
possible in this manner to condense the greater portion of vapors 
of a higher temperature and tension, but with vapors of at the 
utmost 95 F. little success would be attained. The greater 
portion of the vapors remaining uncondensed a very large quan- 
tity of fluid containing but little alcohol would be obtained in 
the course of a day and this fluid could at the best be used only 
instead of water for the preparation of alcoholic liquid. The 
value of the material thus regained would not cover the working 
expenses of the apparatus. By working, however, with the con- 
densing apparatus described above, the condensed alcohol does 
not even contain the total quantity of water evaporated with it, 
and it need only be compounded with the corresponding quantity 
of water and vinegar again to yield alcoholic liquid. 



CHAPTER IX. 

AUTOMATIC VINEGAR APPARATUS. 

THE principal work to be performed in a vinegar factory con- 
sists in pouring at stated intervals the alcoholic fluid into the 
generators. In a large factory several workmen are constantly 
engaged in this work and losses by spilling are unavoidable. 
Further it is almost next to impossible always to pour in the 
same quantity at exactly the same intervals, and sometimes a 



AUTOMATIC VINEGAR APPARATUS. 81 

generator may even be entirely overlooked and thus remain inac- 
tive until the next supply of alcoholic liquid is poured in. 

The greatest disadvantage is, however, the interruption for 
several hours daily of the formation of vinegar in all the genera- 
tors, so that, for instance, in a factory working 16- hours a day, 
one-third of the time is lost. Independently of the small return 
on the capital invested, these interruptions are accompanied by 
many other conditions injurious to the regular running of the 
factory. 

The greatest of these evils is that with the cessation of the sup- 
ply of alcoholic fluid the augmentation of the vinegar ferment 
diminishes and finally ceases altogether. Further, the develop- 
ment of heat in the interior of the apparatus at the same time 
ceases and the temperature is reduced several degrees, this phenom- 
enon appearing even in factories provided with the best heating 
apparatus and keeping up a constant temperature in the workroom 
during the night. 

In the morning when work is resumed, it is in most cases 
necessary to vigorously air the apparatus by opening all the draught 
holes in order to gradually restore the temperature to the required 
degree, and it requires some time before the apparatus again 
works in a normal manner. 

The vinegar ferment, however, is very sensitive to changes of 
temperature as well as to the concentration of the nourishing 
substance surrounding it, and there can be no doubt that its aug- 
mentation is prejudiced by the continuous variations of tempera- 
ture to which it is exposed during the interruptions of several 
hours a day. That such is actually the case is shown by the fact 
that the quantity of vinegar ferment formed in the generators is 
small as compared with that which under conditions favorable to 
the ferment forms in a short time upon alcoholic liquids. 

Besides the debilitation of the vinegar ferment and the conse- 
quent disturbance in the regular working of the factory, the 
repeated reduction of the temperature in the generators has the 
further disadvantage that besides the vinegar ferment other fer- 
ments for whose development a low temperature is more favorable 
may be formed, and these ferments may increase to such an extent 
as to entirely suppress the vinegar ferment. There can scarcely 



&4 VINEGAR, CIDER, AND FRUIT-WINES. 

liquid flows into each generator, rims above the uppermost row. 
Another conduit, L l common to all the generators, serves for the 
reception of the fluid (finished vinegar) running off from the 
lowest row, and conducts it to the collecting vessel, S. The 
arrows indicate the course the alcoholic liquid has to traverse. 

From all appearances the arrangement of a factory according 
to the above-described system would be most advisable, there 
being actually nothing to do but to raise the alcoholic liquid 
once and to remove the finished vinegar from the collecting 
vessel. In practice, however, this so-called terrace system pre- 
sents many difficulties not easily overcome, the greatest un- 
doubtedly being the solution of the heating problem. Experience 
shows that the temperature in a generator must be the higher the 
more acetic acid the alcoholic liquid contains. According to this, 
the highest temperature should prevail in the lowest series of 
generators (///, Fig. 25) and the lowest in the uppermost (J). 

But in practice just the reverse is the case even with the use 
of the best heating apparatus : the highest temperature prevails 
in / and the lowest in JJJ, as, according to natural law, the 
warm air being specifically lighter than the cold constantly strives 
to ascend. 

To overcome this evil nothing can be done but to place the 
series J, //, and III of the generators in as many different stories 
entirely separated from each other, or, in case there is a central 
heating apparatus in the cellar, to correctly distribute the warm 
air in the separate stories by suitably arranged registers. The 
solution of this problem offers no insuperable difficulties, but re- 
quires the arrangement of the entire factory to be carefully 
planned in accordance with the laws of physics. 

An unavoidable evil of the terrace system is the costliness of 
the factory building, and, finally, that a disturbance occurring in 
one of the generators must simultaneously affect two others of the 
vertical series, which must necessarily remain idle until the dis- 
turbance is removed. Considering all the disadvantages con- 
nected with the terrace system, though it is seemingly so suita- 
ble, it is but little adapted to practice, it being much preferable 
to place all the generators on the same level and to divide them 



AUTOMATIC VINEGAR APPARATUS. 85 

into three groups, each of which is provided with a reservoir for 
the alcoholic liquid and a collecting vessel. 

The mode of working according to this system is as follows : 
The alcoholic liquid is pumped into a reservoir, from which it 
passes through group I of generators and collects in a vessel. 
From the latter it is pumped into a second reservoir placed on 
the same level with the first, and runs through group II of gene- 
rators into another collecting vessel ; from there it is again pumped 
into a third reservoir, and after passing through group III of 
generators finally collects as finished vinegar in a third collecting 
vessel. 

Though the arrangement of all the generators on the same 
level renders it necessary to raise the alcoholic liquid three times, 
it would seem more suitable than the terrace system for the fol- 
lowing reasons : 1. By a suitable regulation of the heating ap- 
paratus the required temperature can be readily maintained in the 
separate groups of generators. 2. In case of a disturbance in 
one of the groups, the respective generator can be left out with- 
out causing an interruption in the work of the other groups. 3. 
The power required to pump the alcoholic liquid three times into 
the reservoirs V v V 2 , and F" 3 is not much greater than that 
which has to be used to raise it to the height of the reservoir in 
factories arranged according to the terrace system. 4. Notwith- 
standing the greater area required, the erection of a one-story 
factory is less expensive than that of a three-story building with 
complicated heating apparatus and very strong, solid floors, 
which are required on account of the great weight of the gene- 
rators. 

The uniform distribution of the alcoholic liquid into each 
generator is very simple in factories arranged according to the 
terrace system, and can be effected in the following manner : 

The false bottoms are fitted water-tight in the generators ; they 
are provided either with narrow holes alone, or with apertures 
loosely filled with cotton-wick, pack-thread, etc. The pipes 
ascending from the vinegar forming space, which is filled with 
shavings, are inserted water-tight in the false bottoms. On the 
reservoir containing the alcoholic liquid is a spigot which can be 
accurately adjusted, and is securely connected with the conduit 



86 VINEGAR, CIDER, AND FRUIT- WINES. 

leading to the separate generators. At the place on the conduit 
where the alcoholic liquid is to be introduced into the generator 
is a discharge-pipe also provided with a spigot. 

When the factory is to be put in operation the reservoir is first 
filled with alcoholic liquid, the spigots on the several generators 
being entirely open, but the principal spigot closed. Now, by 
suddenly opening the latter, the air in the conduit is expelled 
by the alcoholic liquid flowing in, and the latter rushes in a full 
stream from the spigots connecting the conduit with the genera- 
tors. These spigots are then closed so far that only the quantity 
of alcoholic liquid required for the regular process of the forma- 
tion of vinegar can enter the generators. To prevent the force 
of pressure from varying too much in the conduit by the lower- 
ing of the level of the fluid in the reservoir, it is recommended 
to give the latter only a slight height but a large bottom surface. 

From the lower portion of the uppermost series of generators 
the alcoholic fluid then gradually reaches through a pipe the false 
bottoms of the next series, and from this the lowest series from 
which it runs oif as finished vinegar into the collecting vessel. 

It will readily be seen that some time for experimenting is 
required before a factory arranged according to this system can 
be brought into regular working order, it being necessary to test 
the fluids running off from the different groups of generators as 
to their contents of acetic acid in order to find out whether too 
much or too little or just enough alcoholic liquid reaches the 
generator so that the liquid running off from the lowest series 
contains no alcohol and may be considered as finished vinegar. 
Any fault in the working of the generators can in this case be 
overcome by a corresponding adjustment of the spigots so as to 
regulate the influx of alcoholic liquid. 

Theoretically no more simple or convenient process for the 
fabrication of vinegar than the terrace system could be devised. 
Provided the spigots supplying the separate generators be once 
correctly adjusted and the temperature of the different stories 
suitably regulated, it is only necessary constantly to supply the 
reservoir with alcoholic liquid and the heating apparatus with 
fuel in order to carry on the work for any length of time desired. 



AUTOMATIC VINEGAR APPARATUS. 87 

The disadvantages connected with this system having already been 
explained need not be further referred to. 

Periodically working Apparatus. The Three-group System. 

In the second system of automatic generators it has been 
sought to imitate the ordinary working of a vinegar factory by 
providing the apparatus with certain mechanical appliances which 
allow of the distribution at certain stated intervals of any desired 
quantity of alcoholic liquid into the generators. The term 
"periodical" may be applied to this system of automatic appa- 
ratus. 

The mechanical appliances used for the purpose of admitting 
at certain intervals a fixed quantity of alcoholic fluid into the 
generator may be constructed in various ways, the tilting trough, 
shown in Figs. 12 and 13, p. 62, being an example. By a modi- 
fication, of the apparatus, as shown in Fig. 26, any desired quan- 
tity of fluid can with its assistance be at certain intervals admitted 
to the generator. The fluid may be either poured out upon the 
false bottom, or, what is more suitable for its better distribution, 
used for feeding a sparger. 

As seen from the illustration a prismatic box, whose bottom is 
formed of two slightly inclined surfaces, stands at a suitable 
height over each generator. In the box a tilting trough is placed 
so that its axis of revolution runs parallel with the line formed 
by the two bottom surfaces of the box. On the point of contact 
of the two surfaces a pipe is inserted which extends to the false 
bottom or the funnel of the sparger. Above the box is a spigot 
connected by a conduit with a reservoir for the alcoholic fluid 
placed at a higher level. This reservoir serves for supplying a 
large number of generators, and can be shut off by a carefully 
adjusted spigot. From the latter a vertical pipe leads to the 
conduit running in a horizontal direction over the generators. 
The conduit is provided with small spigots which discharge the 
fluid into the tilting troughs. 

By giving each tilting trough such a size that, for instance, 
each partition holds 5 quarts, and adjusting the spigot so that 30 
minutes are required for filling one partition, the trough will, at 



88 



VIXEGAR, CIDER, AND FRUIT-WINES. 



the expiration of this time, tilt over and empty the fluid upon 
the inclined surfaces; from here it runs into the sparger and 

Fig. 26. 




Modification of the Tilting-Trougli. 

setting the latter in motion is poured in the form of a fine spray 
over the shavings. Since the other partition of the tilting trough 
has the same capacity as the first and the quantity of alcoholic 
fluid remains the same, the trough will, after the expiration of 30 
minutes, again tilt over, and again empty 5 quarts of fluid, this 
being continued as long as the reservoir contains any fluid. 

In place of the tilting trough the so-called " siphon-barrel" 
(Fig. 27) may be used for effecting the discharge of a certain 
quantity of fluid at a stated interval. In a spherical vessel placed 
at a higher level than the edge of the funnel of the sparger is a 



AUTOMATIC VINEGAR APPARATUS. 



89 



siphon, the longer leg of which passes through the bottom of the 
vessel and enters the funnel. On the edge of the vessel is a 
spigot which is connected with the fluid-conduit and so adjusted 
that within a previously determined space of time the vessel is 
filled with fluid up to the height indicated by the dotted line. As 
soon as the fluid reaches that height, the action of the siphon 




Siphon-barrel. 

commences and the content of the vessel runs through the longer 
leg into the funnel of the sparger until its level is sunk to the 
edge of the shorter leg. The action of the siphon then ceases 
until the vessel is again filled up to the line when it recommences 
and so on. 

The siphon of bent glass tubes being very liable to breakage, 
it is frequently replaced by the so-called bell-siphon the arrange- 
ment of which is shown in Fig. 28. It consists of a glass tube 
which forms the longer leg, of the siphon while a glass cylinder 
secured to this tube by means of a perforated cork represents the 
other leg. The action of this siphon is the same as the other. 

In working with automatic apparatus fixed quantities of fluid 
being at stated intervals introduced, provision for the reception of 



90 



VINEGAR, CIDER, AND FRUIT-WINES. 



the fluid must be made in the apparatus itself, or for its being 
conducted to a special reservoir at the rate at which it trickles 
from the shavings. In the first case the. space beneath the lath- 
bottom must be of sufficient size to receive the fluid passed through 

the apparatus in a certain time. This 
Fi. 28. time being suitably fixed for 12 hours 

the apparatus can during this time 
work without further assistance, so 
that the required space beneath the 
lath-bottom can be calculated by mul- 
tiplying the number of affusions with 
the quantity of fluid poured in at one 
time. 

Example : The generator receives 
at intervals of 30 minutes an affusion 
of 5 quarts, hence in 12 hours 24 affu- 
sions of 5 quarts each = 120 quarts. 
The space beneath the lath-bottom 
must, therefore, be of sufficient capa- 
city to receive up to the height of the 
Bell-siphon. draught-holes at least 120 quarts of 

fluid. 

As will be seen from the following general description of a 
vinegar factory arranged according to the automatic principle, it 
is decidedly preferable to arrange the generators so that the fluid 
trickling from the shavings is at once conducted to a collecting 
vessel. 



Arrangement of a Vinegar Factory working according to the 
Automatic Principle. 

As previously stated, it is not possible to convert all the alcohol 
contained in the liquid into acetic acid by one affusion ; only a 
portion of the alcohol is converted and this semi-product is brought 
into a second generator, and, if the liquid used is very rich in al- 
cohol, into a third. In the second apparatus another portion of 
the alcohol is converted into acetic acid and the process finished 
in the third. 



AUTOMATIC VINEGAR APPARATUS. 91 

It being in all cases advisable to prepare vinegar with a high 
percentage of acetic acid most manufacturers now pass the alco- 
holic liquid successively through three generators. In practice 
it is recommended to place the generators which are to receive 
alcoholic liquid of the same content of acetic acid alongside each 
other, which leads naturally to the division of the generators into 
three groups. If, for instance, a factory contains 48 generators, 
each group contains 16 ; group I is charged with freshly prepared 
alcoholic liquid ; the generators of group II contain the alcoholic 
liquid which has already passed through those of group I, and 
group III is charged with the fluid yielded by group II. 

Besides the easy control of the work, this arrangement into 
groups has another advantage. The generators in which the last 
remnants of the alcohol of a quite strong fluid are to be converted 
into acetic acid are best kept at a somewhat higher temperature, 
and with a suitably arranged heating apparatus and the eventual 
use of curtains by which the workroom can be divided at will 
into two or three partitions, it can be readily arranged to convey 
somewhat more heat to the second group of generators and the 
greatest quantity to the third. 

The height of the actual workroom of the factory should not 
be greater than required by that of the generators. The reservoir 
is placed under the roof of the workroom, while the collecting 
vessels are either sunk in the floor or placed in the cellar. 

Below is given a description of a periodically working estab- 
lishment with 24 generators. The generators are arranged in 
three groups, I, II, and III, the following articles belonging to 
each group : 

8 generators ; 

1 reservoir; 

1 collecting vessel ; 

8 apparatuses for the distribution of the alcoholic liquid into 
the generators ; 

Conduits for the alcoholic liquid to be poured in ; 

Conduits for the alcoholic liquid running off. 

For the three groups in common : 

A pump to convey the alcoholic liquid from the collecting 
vessels to the reservoirs. 



92 VINEGAR, CIDER, AND FRUIT-WINES. 

A channel for the conveyance of the warm air from the heat- 
ing apparatus in the cellar to and distribution in the workroom. 

An apparatus for heating the alcoholic liquid. 

The three reservoirs rest upon the joists of the ceiling of the 
workroom, a small chamber inclosing them being constructed of 
papered boards. In the floor of these chambers is a manhole by 
which the reservoirs can be reached. This manhole should not 
be provided with a door, it being of importance that the reser- 
voirs should be constantly surrounded by warm air which as- 
cends through the manhole. To prevent loss by evaporation the 
reservoirs should be provided with well-fitting covers. 

To retain solid bodies such as shavings, flakes of mother of 
vinegar, etc., which might eventually obstruct the fine apertures 
in the false bottom or sparger, a filter is placed on the end of the 
pipe through which the alcoholic liquid passes into the reservoirs. 
A suitable filter for the purpose is a horse-hair sieve containing a 
linen bag, the latter being from time to time replaced by a new 
one. 

The conduits for the conveyance of the alcoholic liquid to the 
distributing vessels and from there to the generators are best con- 
structed of thick glass tubes, the connection of two pieces being 
effected by pieces of rubber hose pushed over the ends and se- 
cured with twine. 

Each generator may be furnished with a vessel containing the 
automatic arrangement, it being, however, in this case necessary 
to provide for each a special conduit from the reservoir, which for 
a factory containing a large number, of generators is rather ex- 
pensive. Hence it is recommended to use for each group only 
one or at the utmost two distributing vessels, and from them to 
extend smaller conduits to the separate generators. Each of the 
principal conduits is provided, at the place where it enters the dis- 
tributing vessel, with a cock, which is adjusted for the discharge 
of a certain quantity of alcoholic liquid. If, as above mentioned, 
every generator is to receive an affusion of 5 quarts of alcoholic 
liquid every 30 minutes, the distributing vessel serving for a 
group of 8 generators must have a capacity of 40 quarts, and 
the spigot has to be so adjusted that exactly this quantity passes 
through it in 30 minutes. 



AUTOMATIC VINEGAR APPARATUS. 93 

The discharge-pipe of the automatic arrangement must enter a 
space, in which are inserted eight pipes having the same diameter, 
which conduct the alcoholic liquid to the separate generators. By 
this arrangement all the generators receive simultaneously an 
affusion of an equal quantity of fluid, which either sets the 
sparger in motion or gradually trickles through the apertures in 
the false bottom. The alcoholic liquid which has passed through 
the generators collects either in the space under the lath-bottom 
or runs directly through conduits to the collecting vessels. 

The conduits placed before the discharge apertures of the 
generators are intended to conduct the alcoholic liquid to the 
reservoirs, and there being no pressure of fluid in them they 
might be merely of open gutters. For the sake of cleanliness and 
to avoid losses by evaporation it is, however, advisable to use 
glass tubes for the purpose. At the places where the discharge- 
pipes of the generators are located, the connection of two glass 
tubes is effected by a wooden joint with an aperture on top in 
which is placed a glass funnel. For collecting vessels for the 
alcoholic fluid running off from the generators of one group, vats 
provided with lids are used. They have to be placed so low that 
some fall can be given to the conduits, and in each of them is 
a pipe provided with a spigot, which serves as a suction-pipe for the 
pump intended to raise the alcoholic fluid. 

The manner of working in a factory thus arranged is as 
follows :* The collecting vessel S x serves for the preparation of the 
alcoholic liquid, which is then pumped into the reservoir Vj, 
from whence it runs through the first group of generators, E I? to 
the collecting vessel S n . From this it is pumped into Vn, and 
runs through the second group of generators, E n , into the collect- 
ing vessel S m . On being pumped up the third time it runs from 
the reservoir V m through the third group of generators, E m , and 
passes as finished vinegar either into a fourth collecting vessel or 
is at once conducted into storing barrels. 

The distance the alcoholic liquid has to be raised from the 
bottom of the collecting vessels to the reservoir amounting to not 

* To avoid repetition the collecting vessels are designated: Si, n, and m ; 
the reservoirs Vi, u, and m ; the groups of generators EI, u, in. 



94 VINEGAR, CIDER, AND FRUIT-WINES. 

more than from 23 to 25 feet, an ordinary suction-pump may be 
used for the purpose, though a forcing-pump is better, it doing 
the work more rapidly. The pump must be constructed of 
material entirely indifferent to acetic acid (wood, glass, hard 
rubber, tin, or a strongly silvered metal). 

Any metallic vessels used in the factory should be of pure tin, 
i. e., unalloyed with other metals, it being the only metal entirely 
indifferent towards acetic acid, but unfortunately it is too soft to 
be suitable for the construction of pumps. 

The pump is generally located in the immediate neighborhood 
of the collecting vessels, its suction-pipe being divided into three 
branches and fastened into the latter. If one of the collecting 
vessels is to be emptied, the respective spigot is opened and the 
spigots of the other suction-pipes closed. 

Ordinary well or river water being used in the preparation .of 
the alcoholic liquid, the temperature of the latter does not gene- 
rally exceed 54 F., and if it were thus introduced into the gene- 
rators acetification would be very sluggish until the temperature 
rose above 68 F. Independently of the loss of time, there would 
be the further danger of injuring the development of the vinegar 
ferment; hence it is necessary to heat the alcoholic liquid to the 
temperature required. This is best effected by passing it through 
a coil surrounded by hot water. Fig. 29 shows an apparatus es- 
pecially adapted for heating the alcoholic liquid. In a copper or 
iron boiler filled with water, which can be heated from below, is 
a coil, 8, of pure tin ; it enters the boiler above at a and leaves it 
at b, so that the place of influx is at the same level with that of 
discharge. With this form of construction the coil of course re- 
mains always filled with liquid, which with the use of pure tin is, 
however, of no consequence ; besides, this can be remedied by 
placing on the lowest coil a narrow pipe, R, which projects above 
the edge of the boiler and is bent like a siphon. By opening the 
spigot h the fluid contained in the coil runs off through R. 

The rising pipe of the forcing-pump is provided with an ar- 
rangement by which the alcoholic liquid can be brought either 
directly from the collecting vessels into the reservoirs or first 
forced through the heating apparatus. It consists of a prismatic 
wooden body provided with three spigots. By closing spigots 2 



AUTOMATIC VINEGAR APPARATUS. 



95 



and 3 and opening 1, the alcoholic liquid is immediately conveyed 
from the collecting vessel to the reservoir. By closing spigot 1 
and opening 2 and 3, which are connected by short pieces of 
rubber hose with the ends of the coil S, the alcoholic liquid 
forced upward from the collecting vessels by the pump must pass 
through the heating coil, and after being heated it returns to the 

Fig. 29. 




Apparatus for heating the Alcoholic Liquid. 

rising pipe which conveys it to the reservoirs. The arrows in the 
illustration indicate the course the alcoholic liquid has to traverse 
when spigots 2 and 3 are open and 1 closed. 

The diameter and length of the tin coil depend on the quantity 
of fluid which is to pass through it, though one with a clear 
diameter of 12 to 14 inches and a length of 23 to 26 feet will, 
as a rule, suffice ; besides by slower or quicker pumping the fluid 
can be forced with less or greater velocity through the coil and 
correspondingly more or less heated. The walls of the coil 
should be as thin as possible so as to yield heat rapidly. 



96 VINEGAR, CIDER, AND FRUIT-WINES. 

The heating of the alcoholic liquid, of course, can also be 
effected by heating one portion more strongly than necessary and 
reducing it to the required temperature by mixing with cold fluid. 
In working, however, with a fluid containing living vinegar fer- 
ment and such, as will be explained later on, is claimed to be 
already contained in freshly prepared alcoholic fluid care must 
be had not to heat the fluid above 120 F., this temperature being 
destructive to the ferment. 



CHAPTER X. 

OPERATIONS IN A VINEGAR FACTORY. 

Acidulation of the Generators. 

THE object of acidulation is to completely saturate the filling 
of the generators with vinegar and to cause the development of 
the vinegar ferment upon the filling material, shavings, char- 
coal, etc. The generators are first filled with shavings, wooden 
blocks, pieces of charcoal, etc. ; the false bottoms or spargers are 
next placed in position and the temperature of the workroom 
brought close up to 86 F. Acidulation, i. e., saturating the 
shavings with alcoholic liquid, is then commenced, vinegar of the 
same strength, i. e., with the same content of acetic acid, as that 
which is to be manufactured in the generators being used for the 
purpose. Every cubic meter (35.31 cubic feet) of the space filled 
with shavings or charcoal requires for complete acidulation the 
following quantities of vinegar : 

Shavings loosely poured in 230 to 270 liters ( 60.75 to 71.31 gallons). 
Shavings piled up alongside 

each other 340 to 400 " ( 89.8 to 105.65 " 

Charcoal the size of a walnut 540 to 800 " (142.6 to 211.3 " 

The value of this vinegar used for acidulation has to be con- 
sidered as dead capital. 

The first vinegar miming off from the generators is not only 
considerably weaker than that used for acidulation, but, notwith- 
standing the previous lixiviation of the wood, has a disagreeable 



OPERATIONS IN A VINEGAR FACTORY. 97 

taste so as to render it unfit for the preparation of table vinegar, 
and can only be utilized, for instance, in the preparation of ace- 
tate of lead, etc. When the vinegar running off has acquired a 
pure taste, it is collected by itself and later converted into a 
stronger product by mixing it with alcohol and passing again 
through the generators. By this saturation of the shavings with 
vinegar, the vinegar ferment locates in abundance upon the sur- 
face of the shavings and the generators are fit for the formation 
of vinegar. 

The regular fabrication can, however, be commenced only 
gradually, as may be illustrated by the following example : At 
first, for instance, alcoholic liquid is introduced only once a day, 
either early in the morning or in the evening. In about eight 
days, or under certain conditions even later, the temperature in 
the interior has risen to from 86 to 95 F., and alcoholic liquid 
may now be introduced twice daily, for instance, early in the 
morning and in the afternoon. That the generator works, is re- 
cognized by the increased temperature and by the flame of a 
candle held near a draught-hole being drawn inwards. After 8 
to 14 days more the thermometer shows 96 to 98 F., and then 
alcoholic liquid is introduced three times daily, for instance, early 
in the morning, in the forenoon, and in the afternoon, whereby 
the temperature rises to 102 to 104 F. If now the vinegar 
running off shows the intended strength, the generators are in 
good working order and subjected to the regular treatment. 

Accelerated Acidulation. 

By closely considering the processes which must take place in 
acidification and the first stage of the operation, it will be plainly 
seen that the above-described method cannot be called a rational 
one, there being a waste of time as well as of material and the 
commencement of regular working being largely dependent on 
accident. 

The object of acidulation is, as previously stated, first to thor- 
oughly saturate the shavings with vinegar and next to develop the 
vinegar ferment upon them. This can, however, be attained in a 
more suitable and a quicker manner than by the above process. 




(TJ1TIVBRSITY 



98 VINEGAR, CIDER, AND FRUIT-WINES. 

Air-dried wood contains on an average 20 per cent, of water 
and during acidulation this water must be gradually replaced by 
vinegar ; hence the vinegar trickling from the generators will 
remain poor in acetic acid and rich in water until the shavings 
are entirely saturated with pure vinegar and the water is expelled. 

The removal of the water from the shavings and its substitu- 
tion by vinegar are effected by osmose, i. e., the cells of the wood 
surrounded by vinegar yield a fluid consisting of water and ex- 
tractive substances of the wood and absorb sufficient of the 
exterior fluid until both liquids have the same composition. Now, 
by pouring only a small quantity of vinegar at one time over the 
shavings in the generators, as is done in the acidulation according 
to the old method, the course of the process is very slow, 14 days 
or more, as already mentioned, being required before the vinegar 
running off shows no longer a change in its concentration. 

In a generator in a stage of acidulation an uninterrupted 
though slight current of air upwards takes place, since even 
with the use of the best heating apparatus the air in the upper 
layers is warmer than in the lower. This current of air- becomes 
stronger with the development of larger quantities of vinegar 
ferment and causes a large absolute loss of vinegar; the greater 
portion of this loss must be set down as being due to evaporation, 
which must be considerable on account of the great surface over 
which the vinegar is distributed, and the smaller portion to con- 
sumption by the vinegar ferment. 

By placing the shavings in vinegar the above-described process 
of substitution of vinegar for the fluid contained in the cells of 
the wood takes place very quickly, and, theoretically, it would 
therefore seem to be advisable to follow the same course on a large 
scale, i. e., to saturate the shavings with vinegar before placing 
them in the generators. By using artificially dried shavings 
(see p. 67) the saturation is effected in the course of a few hours, 
the dry woody tissue absorbing the fluid like a sponge. 

The shavings, while still hot, are brought into a vat and covered 
with the vinegar to be used for acidulation. In about 12 hours 
they are thoroughly saturated ; the excess of vinegar is drawn off 
through the tap-hole in the bottom of the vat, and having ab- 
sorbed neither water nor extractive substances from the steamed 



OPERATIONS IN A VINEGAR FACTORY. 99 

and thoroughly dried shavings can be immediately re-used for the 
saturation of another portion of shavings. The saturated shav- 
ings are at once used for filling a generator, and the latter, which 
may now be considered as completely acidulated, can at once be 
used for the process of the formation of vinegar according to the 
method described below. 

Instead of in. a vat the shavings can also be saturated directly 
in the generator. For this purpose the shavings, after having 
been artificially dried, are immediately brought into the generator, 
and vinegar is poured over them either by means of the false 
bottom or the sparger until a considerable quantity has accumu- 
lated in the space below the lath-bottom. This accumulation is 
then drawn off and again poured over the shavings, this being 
continued until they are thoroughly saturated, which is effected in 
a comparatively short time. 

Induction of the Operation with artificially raised Vinegar 
Ferment. 

In the accelerated acidulation of the generators no develop- 
ment of vinegar ferment can of course take place, since by heating 
the shavings to about 212 F. any fermenting organisms accident- 
ally adhering to them are destroyed. The vinegar ferment 
increases with astonishing rapidity provided it finds nourishment 
suitable for its development. Vinegar is, however, a very poor 
material for this purpose, and this is very likely the reason why 
weeks are required before fabrication can be commenced in gen- 
erators acidulated according to the old method. The ferment can, 
however, be so rapidly augmented in the generators that fabri- 
cation can be commenced almost immediately after acidulation 
is complete. 

For this purpose a method similar to that employed in the 
manufacture of alcohol and yeast has to be pursued and vigorous 
ferment obtained by cultivation. As previously mentioned the fer- 
ment causing acetous fermentation is widely distributed through- 
out nature and is most abundantly found in the air of thickly 
populated regions. 

The " pure cultivation" of the vinegar ferment, i. e., in which 



100 VINEGAR, CIDER, AND FRUIT- WINES. 

no other than the desired ferment is developed, is not difficult, it 
being only necessary to prepare a fluid especially adapted for its 
nourishment and allow it to stand at a suitable temperature in order 
to obtain in a few days a vigorous growth produced by a few 
individual germs reaching the fluid from the air. The best fluid 
for the purpose is one which contains, besides a large quantity of 
water, about 85 to 90 per cent., a certain amount of alcohol and 
acetic acid and very small quantities of nitrogenous substances 
and mineral salts. Hence its preparation is not difficult, it being 
only necessary to mix ordinary vinegar and alcohol in suitable 
proportions and add a small quantity of a fluid containing nitro- 
genous substances and mineral salts, such as wine, cider, beer or 
malt extract. Numerous experiments have shown that a fluid 
containing from 4 to 6 per cent, of acetic acid and the same 
quantity of alcohol with the addition of a small quantity of one 
of the above-mentioned fluids is best adapted for the vigorous 
nourishment of the vinegar ferment. Ordinary table vinegar 
contains as a rule from 4 to 6 per cent, of acetic acid ; the ave- 
rage percentage of alcohol is in wine from 8 to 10 ; in cider from 
4 to 6 ; and in beer from 3 to 5. Taking this statement as a 
guide, the preparation of a fluid containing from 4 to 6 per cent, 
of acetic acid, 4 to 6 per cent, of alcohol, and the required nitro- 
genous combinations and salts will not be difficult. 

Fluids of this composition are obtained by mixing, for in- 
stance, equal parts of cider and vinegar, or one part of wine 
with two of vinegar, or one part of beer with three of vinegar, 
and adding 5 per cent, of 90 per cent, alcohol to the mixture. 
Such mixtures possessing the power of vigorously nourishing the 
vinegar ferment can at the same time be considered as types for 
the preparation of alcoholic liquid of suitable composition. 

To assure the exclusive development of vinegar ferment upon 
any of the above-mentioned mixtures it is best to heat it to the 
boiling point of water. Young wine as well as cider contains 
considerable quantities of albuminous substances in solution, and 
fluids of this nature being well adapted for the nourishment of 
the mold ferment, the development of the latter 'might increase 
to such an extent as entirely to suppress the vinegar ferment and 
thus render its cultivation a failure. Beer is also very suitable 



OPERATIONS IN A VINEGAR FACTORY. 101 

for the nourishment of the mold ferment, though in a less degree 
than young wine, and besides living yeast contains alcoholic 
ferment. 

By heating wine or beer only for a moment to about 158 F., 
a large portion of the albuminous substances in solution becomes 
insoluble, and on cooling separates as a flaky precipitate, all fer- 
ments present in the fluid being at the same time destroyed. 
Hence for the preparation of a fluid especially adapted for the 
cultivation of pure vinegar ferment, it is recommended quickly to 
heat to the boiling point 1 quart of ordinary white wine in a 
covered porcelain vessel, and, after cooling to the ordinary tem- 
perature, to mix it with 2 quarts of vinegar. To remove the 
separated insoluble albuminous substances it is filtered through 
blotting paper. 

To prepare a nourishing fluid from beer, heat 1 quart to the 
boiling point, mix it after cooling with 3 quarts of vinegar, add 
^ quart of 90 per cent, alcohol, and filter. 

Distribute this fluid in a number of shallow porcelain vessels 
and place the latter near a window in the heated workroom. To 
prevent dust from falling into the fluid cover each dish with a 
glass plate resting upon two small wooden sticks placed across 
the dish. In two or three days, and sometimes in 24 hours, the 
commencement of the development of the vinegar ferment will 
be recognized by the stronger odor of vinegar than that possessed 
by the original fluid and by the appearance of the surface of 
the liquid. By observing the latter at a very acute angle, dull 
patches resembling grease stains and consisting of a large number 
of individuals of the vinegar ferment will be seen. In a few 
hours these patches have increased considerably, until finally the 
entire surface appears covered by a very delicate veil-like layer 
of vinegar ferment. 

By touching the surface with the point of a glass rod a certain 
amount of the coating adheres to it, and by rinsing it off in a fluid 
of similar composition not yet inoculated the ferment quickly de- 
velops upon it. By placing a drop of the fluid under the micro- 
scope a picture similar to that shown in Fig. 2, p. 29, presents 
itself: the entire field of vision is covered with germs of vinegar 
ferment. 



102 



VINEGAR, CIDER, AND FRUIT-WINES. 



By the development of mold ferment the cultivation of pure 
vinegar ferment may sometimes result in failure even with the 
use of the above-mentioned fluids. The development of this 
ferment is recognized by the appearance of white dots upon the 
fluid, which quickly increase to white opaque flakes, and if left 
to themselves finally combine to a white skin of a peculiar 
wrinkled appearance. Fig. 30 shows a microscopical picture 




Abortive Cultivation of Vinegar Ferment. X 500. 

of such abortive cultivation of vinegar ferment. By observing 
at the commencement of this phenomenon the fluid with the 
microscope, very small individuals of vinegar ferment, 6, will be 
observed alongside of the much larger oval cells a, of the mold 
ferment. Such fluid being not adapted for our purposes has to 
be removed and the dish rinsed off with boiling water. 

When the fluid in the dishes is entirely covered with pure 
vinegar ferment, it is poured into a vessel containing the greater 
portion of the alcoholic fluid intended for the first charge of the 
generators, and in the course of 10 hours the entire surface of 
this fluid is covered with vinegar ferment. This fluid being 
poured into the sufficiently acidulated generators and trickling 



OPERATIONS IN A VINEGAR FACTORY. 103 

gradually through them, the greater portion of the ferment ad- 
heres to the shavings, and increases with such rapidity that the 
strong rise of temperature in the interior of the generators 
shortly indicates the regular beginning of their activity, and the 
effusion of alcoholic liquid can be commenced at once. 

Vinegar ferment developed upon one of the above-mentioned 
fluids is evidently so constituted that it can be thoroughly nour- 
ished by it, and hence the generators might be continued to be 
charged with alcoholic liquid of a corresponding composition. It 
being, however, as a rule, desired to manfacture as strong a pro- 
duct as possible, an alcoholic liquid much richer in alcohol than 
the above-mentioned nourishing fluids has to be used. 

By, however, suddenly changing the nourishing fluid of the 
vinegar ferment, for instance, from a fluid containing only 4 to 
6 per cent, of alcohol to one with 12 to 13 per cent., the action 
of the ferment would very likely be sluggish before it became 
accustomed to the new conditions. Further, its activity might 
suffer serious disturbance and its augmentation decrease very 
sensibly, so that notwithstanding strong heating of the workroom 
and thorough ventilation of the generators, the temperature in 
the latter would suddenly fall, and would only be restored to the 
required degree after the ferment had become accustomed to the 
new conditions and recommenced its vigorous augmentation. 

To overcome such annoying disturbances it is only necessary to 
gradually change the composition of the nourishing fluid to that 
which the alcoholic liquid to be worked in the generators is to 
have. Commencing, for instance, with an alcoholic liquid con- 
taining 5 per cent, of alcohol, the next day one with 6 per cent, 
is used, the succeeding day one with 7 per cent., and so on until 
the maximum percentage of alcohol the liquid is to have is 
reached. 



104 VINEGAR, CIDER, AND FRUIT-WINES. 



CHAPTER XL 

PREPARATION OF THE ALCOHOLIC LIQUID. 

UNDER the term " alcoholic liquid" is to be understood every 
fluid to be converted into vinegar which, besides water and small 
quantities of nourishing salts and albuminous substances, does 
not contain over 14 per cent, of alcohol. In the directions 
generally given for the preparation of such liquids vinegar is 
mentioned as an indispensable constituent. While it cannot be 
denied that a content of vinegar in the alcoholic liquid exerts a 
favorable effect upon the formation of vinegar, it must be ex- 
plicitly stated that it is not the acetic acid in the vinegar, which 
in this case becomes active, but the ferment contained in it. 

In a vinegar factory vinegar just finished and entirely turbid 
is always used for the preparation of alcoholic liquid, and a 
microscopical examination shows such vinegar to contain in- 
numerable germs of vinegar ferment. This ferment on coming 
in contact with much air in the generators will evidently increase 
rapidly and contribute to the quick acetification of the alcohol. 
That it is actually the ferment in the vinegar used which exerts 
a favorable effect can be shown by a simple experiment. By 
adding vinegar previously heated to from 140 to 158 F. to the 
alcoholic liquid the formation of vinegar in the generators pro- 
ceeds more slowly, the ferment contained in the vinegar having 
been killed. 

The best proof, however, that the alcoholic liquid does not re- 
quire any considerable quantity of acetic acid for its conversion 
into vinegar is furnished by the behavior of wine. Correctly 
prepared wine of a normal composition contains only a few ten 
thousands of its weight of acetic acid, and this must very likely 
be considered as a product of vinous fermentation. If such wine 
be stored for years in a cool cellar, its content of acetic acid does 
not change. By, however, exposing such wine in a shallow 



PREPARATION OF THE ALCOHOLIC LIQUID. 105 

vessel to the air at from 66 to 78 F., microscopical examina- 
tion will show the development of vinegar ferment upon it and a 
chemical analysis a constant increase, soon amounting to several 
per cent, of acetic acid. A fluid composed of 5 to 6 per cent, of 
alcohol, 94 to 95 per cent, of water, and a very small quantity of 
malt extract acts in a similar manner. In many cases the vinegar 
ferment is developed without the fluid containing acetic acid. 

The alcoholic fluid to be used may from the start contain a 
sufficiently large percentage of alcohol to correspond to the de- 
sired strength of the vinegar to be made ; in this case the fluid 
has to be poured several times into the generators, it being impos- 
sible to convert a large quantity of alcohol into acetic acid by 
passing it through but once. By another method an alcoholic 
liquid is first prepared containing but little alcohol, which is 
almost completely converted into acetic acid by one passage 
through the generators. The fluid running off from the gene- 
rators is then further mixed with a certain quantity of alcohol 
and being poured into a generator, in which the vinegar ferment 
is already accustomed to larger quantities of alcohol and vinegar, 
is also converted into acetic acid. More alcohol can then be 
added, and so on. The last method is evidently the best as re- 
gards the conditions of life of the vinegar ferment, and actually 
the only one by which the strongest vinegar (with from 12 to 13 
per cent, of acetic acid) can be obtained in generators. 

That it is advisable only gradually to increase the content of 
alcohol in the alcoholic liquid is shown by the behavior of the 
ferment towards alcohol and acetic acid. Both bodies, if present 
in large quantities, are decidedly inimical to the augmentation of 
the ferment, a fluid containing from 14 to 15 per cent, of alcohol, 
or as much acetic acid, being capable of checking the augmenta- 
tion of the ferment to such an extent as to disturb the process of 
fabrication. 

Another argument against the use of the total quantity of 
alcohol in the preparation of the alcoholic liquid to be employed 
for the first effusion, is the fact that evidently more alcohol will 
be lost by evaporation than by commencing with a fluid contain- 
ing less alcohol, arid adding a corresponding quantity of the 
latter after the fluid has once passed through the generators. 



106 VINEGAR, CIDER, AND FRUIT-WINES. 

The quantity of alcohol for the first effusion should be so chosen 
that the fluid running off still contains a small quantity of un- 
changed alcohol, this being an assurance that only alcohol and 
not unfinished acetic acid has undergone an alteration. As long 
as alcohol is present in the alcoholic liquid the vinegar ferment is 
almost entirely indifferent towards acetic acid, but after the oxi- 
dation of all the alcohol it attacks the acetic acid and decomposes 
it to carbonic acid and water. This can be shown by a very 
simple experiment. If finished vinegar, instead of alcoholic 
liquid, be poured into a generator in full operation, the vinegar 
running off shows a smaller percentage of acetic acid than that 
poured in, the acetic acid wanting having been destroyed by the 
ferment. 

To what an extent even smaller quantities than 14 to 15 per 
cent, of alcohol or acetic acid exert a restraining influence upon 
the augmentation and activity of the vinegar ferment can be seen 
in generators charged with alcoholic liquid of different strengths : 
those containing less concentrated liquid can in the same time 
form a much larger quantity of acetic acid than those ill which a 
liquid is used which already contains certain quantities of acetic 
acid. Hence the greater the quantity of acetic acid already con- 
tained in the alcoholic liquid the slower the conversion of the 
alcohol still present into acetic acid. 

It may, therefore, be laid down as a rule that the manufacturer 
should not strive to prepare vinegar with more than about 12 
per cent, of acetic acid. Though in exceptional cases a product 
with 13 per cent, can be obtained, it will also be observed that 
the respective generators gradually yield a weaker product or that 
their activity suddenly ceases to such an extent as to require them 
to be placed out of operation.. 

The preparation of high-graded vinegar being undoubtedly 
subject to greater difficulties than that of a weaker product, 
the question might be raised whether the manufacture of weak 
vinegar only would not be the most suitable. This must be 
largely decided by local conditions. For a manufacturer whose 
custom lies in the immediate neighborhood, for instance, in a 
large city, the production of weak vinegar only would be advis- 
able, but if he has to send his product a considerable distance, 



PREPARATION OF THE ALCOHOLIC LIQUID. 107 

the fact that the more freight has to be paid on what is of no 
value, the weaker the vinegar is, and that the expense of trans- 
porting a strong article is relatively less, deserves consideration. 
The consumer can readily prepare vinegar of any desired strength 
by diluting the strong product with water. 

The quantity of beer required for the purpose of offering suit- 
able nourishment to the vinegar ferment is very small, an addition 
of 1 per cent, to the alcoholic liquid being ample. Sour or stale 
beer can of course be used. The reason for the employment of 
larger quantities of beer in mixing the alcoholic fluids is found 
in the fact that the vinegar prepared from such mixtures sooner 
acquires a pure taste than that made from fluids containing but 
little beer. The addition of beer should, however, not exceed 15 
per cent, of the total quantity of alcoholic liquid, as on account 
of the comparatively high percentage of albuminous substances 
and the maltose, dextrin, and extractive matters of hops it con- 
tains, a larger quantity would be injurious to the process of acetous 
fermentation, the generators being frequently rendered inactive by 
the so-called " sliming of the shavings." The production of the 
latter is due to the fact that by being partially excluded from 
contact with the air by the comparatively thick fluid passing over 
it, the vinegar ferment deposited upon the shavings assumes the 
form of mother of vinegar which adheres to the shavings as a 
slimy mass. 

The quantity of finished vinegar added to the alcoholic liquid 
varies between 10 and 33 per cent. The use of large quantities 
is, however, decidedly inexpedient since. the only effect produced 
by the vinegar is, as previously stated, due to the ferment con- 
tained in it. Of freshly prepared, turbid vinegar 10 per cent, is 
ample for the preparation of alcoholic liquid ; a greater quantity 
can only be considered as useless ballast. 

Theoretically a certain quantity of alcohol yields exactly a 
certain quantity of acetic acid ; the following table shows the 
proportions between the two bodies : 



108 



VINEGAR, CIDER, AND FRUIT-WINES. 





Consists of kilo- 


Aad yields 


In the whole. 


A fluid with 


grammes of 






per cent, 
by volume 
of alcohol. 


Alcohol. 


Acetic 
Water. anhydride. 


Water. 


Vinegar. 


With per cent, 
of acetic 
anhydride. 


1 


0.8 


99.2 


1.0 


99.5 


100.5 


1.0 


2 


1.6 


98.4 


2.1 


99.0 


101.1 


2.1 


3 


2.4 


97.6 


3.1 


98.5 


101.6 


3 1 


4 


3.2 


96.8 


4.2 


98.0 


102.2 


4.1 


5 


4.0 


96.0 


5.2 


97-6 


102.8 


5.1 


6 


4.8 


95.2 


6.3 


97.1 


103.3 


6.0 


7 


5.6 


94.4 


7.3 


96.6 - 


103.9 


7.0 


8 


6.4 


93.6 


8.3 


96.1 


104.4 


8.0 


9 


7.2 


92.8 


9.4 


95.6 


105.0 


8.9 


10 


8.0 


91.9 


10.4 


95.0 


105.4 


9.9 


11 


8.9 


91.1 


11.6 


94.6 


106.2 


10.9 


12 


9.7 


90.3 


12.6 


94.1 


106.7 


11.8 



Practically less vinegar with a smaller percentage of acetic an- 
hydride is, however, always obtained, this being due to losses- of 
material caused partially by evaporation and partially by the 
oxidation of the alcohol extending beyond the formation of acetic 
acid. In preparing the alcoholic liquid these unavoidable losses 
must be taken into consideration and more alcohol be used for the 
production of vinegar with a determined percentage of acetic acid 
than is theoretically required. How much more has to be taken 
depends on the kind of apparatus used and on the strength the 
vinegar to be prepared is to show. The higher the percentage of 
acetic acid which is to be obtained, the greater the losses will be 
and consequently the greater the content of alcohol in the alco- 
holic liquid must be. Theoretically one per cent, of alcohol yields 
one per cent, of acetic acid ; practically the proportions are, how- 
ever, as follows : 



For the production of 
vinegar with a content 
of acetic acid of 

5 per cent. 

6 " 



9 

10 
11 
12 



Is required an alco- 
holic liquid with a 
content of alcohol of 

. 5.4 to 5.5 per cent. 

. 6.5 " 6.6 " 

7.7 " 

8.8 " 

9.9 " 
11.0 " 



7.6 

8.7 

9.8 

10.9 



11.9 
13.0 



12.1 
13.2 



PREPARATION OF THE ALCOHOLIC LIQUID. 109 

The strength of commercial alcohol varying considerably it is 
of importance to the manufacturer to be able to calculate in a 
simple manner how many gallons of water have to be added to 
alcohol of known strength in order to obtain an alcoholic liquid 
with the desired percentage of alcohol. The calculation is exe- 
cuted as follows : 

Suppose : 

P = per cent, of alcohol in the spirits to be used. 

E = per cent, of alcohol in the alcoholic liquid to be prepared, 
the quotient obtained by dividing P by E gives the volume to 
which the spirits have to be reduced by the addition of water in 
order to obtain alcoholic liquid with the desired percentage of 
alcohol. 

Example : 

From spirits of 86 per cent. Tralles' alcoholic liquid with 11 
per cent, of alcohol is to be prepared. 

P 
P= 86; E= 11 = 7.818. 

Hence one volume of the spirits to be used has to be brought 
to 7.818 volumes, or to 1 gallon of spirits 6.818 gallons of water 
have to be added. 

Examples of the composition of alcoholic liquid : 

A. Alcoholic liquid from alcohol, water, and vinegar : 

For vinegar with about 7 per cent, of acetic acid. Alcohol of 
90 per cent. Tr. 10 parts by volume, water 107, vinegar with 7 
per cent, of acetic acid 12. 

For vinegar with about 12 per cent, of acetic acid. Alcohol of 
90 per cent. Tr. 10 parts by volume, water 65, vinegar with 12 
per cent, of acetic acid 7. 

It is advisable to add about 1 per cent, of the entire volume of 
beer to the above alcoholic liquids. 

B. Alcoholic liquid from alcohol, water, vinegar, and beer. 
For vinegar with about 5 per cent, of acetic acid. Alcohol of 

90 per cent. Tr. 10 parts by volume, water 107, vinegar with 
5 per cent, of acetic acid 13, beer 14. 

C. For vinegar with about 8 per cent, of acetic acid. Alcohol 
of 90 per cent. Tr. 10 parts by volume, water 92, vinegar with 
8 per cent, of acetic acid 10, beer 9. 



110 VINEGAR, CIDER, AND FRUIT-WINES. 

In many factories it is customary not to determine the compo- 
sition of the alcoholic liquid by calculation, but simply to work 
according to certain receipts. Vinegar of a certain percentage is 
obtained, but its strength cannot be predetermined with the same 
nicety as by calculating the percentage of alcohol in the alcoholic 
liquid by the above formula, The following may serve as ex- 
amples of such receipts : 

D. Alcohol of 50 per cent. Tr. 100 quarts, water 600, 
vinegar 900. 

E. Alcohol of 90 per cent. Tr. 100 quarts, water 1200, 
vinegar 300. 

F. Alcohol of 90 per cent. Tr. 100 quarts, water 1350, 
vinegar 175, beer 175. 

G. Alcohol of 90 per cent. Tr. 100 quarts, water 1400, 
vinegar 300, beer 100. 

H. Alcohol of 80 per cent, Tr. 100 quarts, water 850, 
beer 750. 

I. Alcohol of 50 per cent, Tr. 100 quarts, water 100, beer 
100. 

The mixtures A, B, and C are only given as examples of how 
alcoholic liquids which yield vinegar containing the desired per- 
centage of acetic acid are prepared according to receipts. Though 
it may be very convenient for the manufacturer to work according 
to such receipts as are given under D to I, their use without a 
previous examination cannot be recommended. It is far better 
for the manufacturer to prepare the alcoholic liquid according to 
a receipt of his own and not shrink from the slight labor it in- 
volves ; he has then at least the assurance of obtaining vinegar 
with exactly the percentage of acetic acid desired, and is in the 
position to obtain an accurate view of the entire process of the 
operation. 

Spirits of wine being the initial point in the preparation of 
alcoholic liquid, it is necessary to know exactly the per cent, by 
weight of alcohol it contains. With the assistance of the tables 
at the end of this volume, the content of alcohol in spirits of wine 
can be readily determined by means of the alcoholometer and 
thermometer. 

With the temperature of the spirits of wine at exactly 59 F., 



PKEPAKATION OF THE ALCOHOLIC LIQUID. Ill 

it suffices to determine its specific gravity by testing with an areo- 
meter and to find the indicated figure in Table I. (Hehner's 
alcohol table). The figure in the next horizontal column gives 
the per cent, by weight and the next the per cent, by volume of 
alcohol contained in the spirits of wine examined. Tables II., 
III., and IV. give data relating to the proportion between the 
specific gravity, and per cent, by weight and volume of spirits of 
wine of various concentration as well as the decrease in volume 
by mixing with water. Table V. shows the relation between the 
statements of Tralles's alcoholometer and a few others used in 
different places. 

The specific gravity as well as the volume of spirits of wine 
varies with the temperature, and the statements of the areometer 
for temperatures above the normal of 59 F. require a corre- 
sponding correction, the execution of which is simplified by the 
use of Tables VI. and VII. It being desirable, especially 
during the cold season of the year, to raise the temperature of 
the spirits of wine by mixing with water, Table VIII. shows 
how much water has to be added in order to obtain from 100 
liters (105.6 quarts) of spirits of wine of known strength 
whiskey of any desired concentration. 

In order to know exactly the yield of acetic acid which is ob- 
tained from a given quantity of alcohol, the acetic acid con- 
tained in the vinegar added must necessarily be taken into ac- 
count as well as the alcohol in the beer, which is of course 
converted into acetic acid. Ifc is best to make the content of 
alcohol in the alcoholic liquid so that it produces vinegar whose 
strength corresponds with that of the vinegar added. If, for in- 
stance, vinegar with 7 per cent, of acetic acid is used, alcohol of 
7.6 to 7.7 per cent, by weight would have to be employed accord- 
ing to the table on p. 108. The following compilation shows the 
manner of preparing alcoholic liquid according to rational prin- 
ciples. 

Suppose vinegar with 7 per cent, acetic acid is to be prepared. 
There would be required 

Spirits of wine of 7.6 to 7.7 per cent, by weight 100 liters (105.6 quarts). 
Vinegar with 7 per cent, of acetic acid . . 10 " ( 10.56 " ) 
Beer 30 " ( 10.56 " ) 



112 VINEGAR, CIDER, AND FRUIT- WINES. 

Suppose the beer contains, for instance, exactly 3 per cent, by 
weight of alcohol, hence 300 grammes (10.58 ounces) in 10 liters 
(10.56 quarts). According to this, a result of 120 liters (126.78 
quarts) of vinegar with exactly 7 per cent, of acetic acid could 
not be expected, since 10 liters (10.56 quarts) of the alcoholic 
liquid do not contain, as should be the case, 760 to 770 grammes 
(26.82 to 27.18 ounces) of alcohol, but only 300 grammes (10.58 
ounces). Hence actually to obtain vinegar with 7 per cent, of 
acetic acid a sufficient quantity of spirits of wine will have to be 
added to the alcoholic liquid to increase the content of alcohol by 
460 to 470 grammes (16.22 to 16.57 ounces), or spirit of wine 
with more than 7.6 to 7.7 per cent, by weight will have to be 
used from the start. 

It will, of course, be understood, that the data given above 
hold good only for the quality of the vinegar in reference to its 
content of acetic acid, the factor of the qualitative yield being 
left out of consideration. The material lost in the course of pro- 
duction amounts, as previously stated, to at least 15 per cent., 
and in determining the quality of the vinegar to be produced 
this circumstance has to be taken into consideration. 

The content of acetic acid in vinegar can be determined with 
great ease and accuracy (up to T ^ per cent.) by volumetric 
analysis, and from the result of such determination it can be 
readily seen how near the correct proportion of alcohol in the 
alcoholic liquid has been attained, and should the latter contain 
too little of it, it can be readily brought up to the determined per- 
centage by the addition of some strong spirit of wine, or, if too 
much, by the addition of some water. 

Constitution of the Fundamental Materials used in the Preparation 
of Alcoholic Liquids. 

Spirits of wine, water, vinegar, and in most cases beer, con- 
stitute the fundamental materials for the preparation of alcoholic 
liquids. 

Any kind of wholesome drinking water is suitable for the 
fabrication of vinegar ; water containing a large amount of or- 
ganic substance or living organisms or which possesses a specific 



PREPARATION OF THE ALCOHOLIC LIQUID. 113 

taste from the admixture of salts should not be used under any 
circumstances. 

Many well-waters are very hard, i. e., they contain a compara- 
tively large quantity of calcium carbonate in solution. If such 
water be used in the preparation of alcoholic liquid, the calcium 
carbonate is decomposed by the acetic acid and the vinegar con- 
tains a corresponding quantity of calcium acetate in solution. 
Other well-waters contain a large quantity of gypsum (calcium 
sulphate) in solution ; which salt is not changed by acetic acid, but 
remains partially dissolved in the finished vinegar. 

When water very rich in gypsum is mixed with alcohol the 
fluid at first entirely clear becomes in a short time opalescent and 
finally perceptibly turbid. After long standing a very delicate 
white sediment separates on the bottom of the vessel, the fluid 
becoming again clear. This phenomenon is explained by the fact 
that gypsum while soluble in water with comparative ease is next 
to insoluble in a fluid containing alcohol, and hence gradually 
separates in the form of minute crystals. 

Water containing no gypsum but much calcium carbonate 
shows after mixing with spirits of wine a similar behavior ; it at 
first becomes turbid and again clear after separating a delicate 
white precipitate. Calcium carbonate is soluble only in water 
containing a corresponding quantity of carbonic acid ; on standing 
in the air the carbonic acid escapes and the calcium carbonate 
separates. 

This behavior of w r ater when mixed with alcohol and standing 
in the air can be utilized for the almost complete separation of 
the gypsum and calcium carbonate. Mixtures of water and alco- 
hol, in the proportion the alcoholic liquids are to have, are first 
prepared and the fluid stored in barrels in a warm apartment 
near the workroom. The mixtures at first turbid become clear 
after some time and are then drawn off from the sediment by 
means of a rubber hose. A comparative examination of the 
water and the mixtures shows that the latter contain only very 
small quantities of gypsum and calcium carbonate in solution. 

River water, though generally soft, i. e., poor in the above-men- 
tioned salts, is seldom sufficiently clear to be used without previous 
filtration. It is further very likely that the small worms, known 
8 



114 VINEGAR, CIDER, AND FRUIT- WINES. 

as vinegar eels, which frequently become very annoying in vine- 
gar factories, reach the alcoholic liquid through the use of river 
water, and, therefore, the use of well-water wherever possible is 
recommended. 

The constitution of the spirits of wine used in the preparation 
of the alcoholic liquids is of great importance, the bouquet of 
the vinegar to be prepared depending on it. Commercial spirits 
of wine always contains certain foreign bodies known as " fusel 
oils ;" they have a very intense odor and can only be removed by 
careful rectification. For the vinegar manufacturer it is of great- 
importance to know the behavior of spirits of wine containing 
fusel oil when converted into acetic acid, and a number of experi- 
ments with different varieties (from potatoes, grain, wine) have 
shown the respective vinegar also possessed of a specific odor, 
differing, however, from that of the original fusel oil and develop- 
ing by storing into a bouquet of a peculiar but agreeable scent. 
This phenomenon is explained by the fact that the energetic 
oxidizing process which takes place in the generators extends not 
only to the alcohol but also to the other bodies present, and the 
greater portion of the fusel oils is thereby converted into odori- 
ferous combinations or compound ethers. 

By treating potato fusel oil (amyl alcohol) with sulphuric acid 
and an acetate, amyl acetate is formed which in a diluted state 
smells like jargonelle pears and is used by confectioners under the 
name of " pear essence" for flavoring so-called fruit bonbons. 
The same process would seem to take place by passing spirits of 
wine containing potato fusel oil through the generators ; the vine- 
gar prepared from such spirits of wine shows an agreeable scent 
immediately when running off from the generators, while vinegar 
prepared from entirely pure spirits of wine has at first a stupe- 
fying smell and acquires a harmonious odor only by long storing. 

It would, therefore, be advisable for the manufacturer who 
works with potato alcohol not to use the highly rectified product, 
but a mixture of it and of crude spirits containing fusel oil, 
the vinegar prepared from such a mixture acquiring a more agree- 
able odor than that obtained from the rectified product. How 
much of the crude spirits has to be used can only be determined 



WORK IN A VINEGAR FACTORY. 115 

by experience, but, as a rule, only enough should be taken to assure 
the conversion of the entire quantity of amyl alcohol present. 

The fuse), oil contained in spirits of wine from grain consists 
largely of a mixture of fatty acids and offers far greater resistance 
to oxidation in the generators than amyl alcohol. The same may 
be said of renanthic ether, the fusel oil of brandy. In working 
with alcoholic liquid prepared with a large quantity of grain 
spirits containing fusel oil, the smell of unchanged fusel oil is 
perceptible in the vinegar besides the odors of the products of 
its decomposition. With the use of small quantities of grain spirits 
containing fusel oil, vinegar possessing a more agreeable odor than 
that from entirely pure spirits is obtained. 



CHAPTER XII. 

EXECUTION OF THE WORK IN A VINEGAR FACTORY. 

THE factory being once in a proper state of working, the fur- 
ther execution of the operation is very simple; a previously 
determined quantity of alcoholic liquid is at stated intervals 
admitted to the generators and the vinegar running off collected, 
\Vith the operation running a normal course, attention has only 
to be paid to the maintenance of the correct temperature in the 
workroom and in the generators ; the chemical process runs its 
regular course without further assistance. In many cases, how- 
ever, deviations from the regular order occur. They are due to 
external influences, such as changes in the temperature in the 
interior of the generators, variations in the composition of the 
alcoholic liquid, etc., and will be discussed in a special chapter. 

The capacity of a factory deperfds on the number of generators 
in operation. A regularly working generator is supposed to be 
capable of daily converting 3 liters (3.16 quarts) of absolute alcohol, 
and this quantity will be taken as the basis for calculating the 
execution of the operation. If, for instance, vinegar with 8 per 
cent, of acetic acid is to be manufactured, alcohol of 8.8 per cent, 
by weight has to be used, and to prepare this, 3 liters (3.10 



116 VINEGAR, CIDER, AXD FRUIT- WINES. 

quarts) of 100 per cent, alcohol have to be reduced with water, 
so that, according to Table I., the fluid shows a specific gravity 
of 0.9858 at 59 F. According to Table III., 8.98 liters (9.48 
quarts) of water have to be added to every liter (1.05 quart) of 
100 per cent, alcohol to obtain spirits of wine of 8.8 per cent, 
by weight; hence 3 liters (3.16 quarts) have to be compounded 
with 26.94 liters (28.46 quarts) of water (according to Table 
III., alcohol with 90 per cent, by volume of alcohol contains 
11.80 per cent, by volume of water, 80 per cent, alcohol 22.83, 
etc., which has to be taken into consideration in making the 
dilution). 

According to Table III., the contraction in this case amounts 
to 0.799 part by volume for every 100 parts by volume of the 
fluid. Hence the 3 liters (3.16 quarts) of 100 per cent, alcohol 
yield, when diluted to spirits of wine of 8.8 per cent, by weight, 
26.94 + 3=29.94 liters (31.62 quarts) of fluid. Actually the 
quantity is somewhat smaller, as in mixing alcohol with water a 
decrease in volume takes place. If the alcoholic liquid is to con- 
tain 10 per cent, each of vinegar and beer, the quantity of fluid is 
as follows : 

Dilute spirits of wine . . . 29.94 liters (31.62 quarts) 
Vinegar with 8 per cent, acetic acid 2.994 " ( 3. 162 " ) 
Beer 2.994 " ( 3.162 " ) 

35.928 " (37.944 " ) 

Hence the quantity to be worked in a generator in the course 
of a day amounts to 35.928 liters (37.944 quarts), or taking into 
account the alcohol (about 90 grammes or 3.17 ozs.) contained in 
the beer, to about 36 liters (38 quarts). And this quantity has 
in a corresponding manner to be divided among the separate 
affusions, so that in a working time of 1 5 hours an affusion of 
2.4 liters (2.53 quarts) would have to be made every hour. How- 
ever, by this method, too much alcohol would be lost by evapora- 
tion, on the one hand, and, on the other, the generators would work 
comparatively slowly, since it is well known that the conversion into 
acetic acid is effected with greater rapidity when the alcoholic 
liquid contains less alcohol. Hence it is recommended to use in 
the commencement a fluid which contains only about one-half or 
two-thirds of the total quantity of alcohol and to add a corre- 



WORK IN A VINEGAR FACTORY. 117 

spending quantity of strong spirits of wine to every fresh affu- 
sion. 

As soon as all the alcohol is converted into acetic acid, the 
vinegar ferment, as previously mentioned, commences with great 
energy to oxidize the latter to carbonic acid and water, and hence 
the amount of spirits of wine added to the alcoholic liquid must 
be so large that the vinegar running off always contains a minute 
quantity of it. 

Much has been written about this gradual strengthening of the 
alcoholic liquid with alcohol, and explicit directions are given 
as to the original composition of the alcoholic liquid as well as to 
how much, how often, and when the alcohol is to be added. 
These directions may have proved useful in many cases, but local 
conditions exert too great an influence upon the process of fabri- 
cation for them to be of general value. Besides the content of 
alcohol in the alcoholic liquid, the size of the generators, the 
strength of the draught in them, the temperature prevailing in 
the workroom and in the interior of the generators, are factors 
which must be taken into consideration in determining on a plan 
of operation actually adapted to existing conditions. 

The size of the generators is, of course, fixed once for all ; in 
a proper state of working the strength of the current of air must 
be so regulated that the temperature in the interior of the gene- 
rators is only about 45 F. higher than that of the workroom, which 
is readily accomplished with a suitable central heating apparatus. 
There still remains the determination of the most favorable pro- 
portion of the content of alcohol in the alcoholic liquid to be first 
used and its gradual strengthening by the addition of spirits of 
wine, which can only be effected by a chemical examination of 
the fluid running off from the generators. 

This chemical examination is restricted to the accurate deter- 
mination of the quantity of acetic acid in the fluid and to that of 
the alcohol to 0.1 per cent. The determination of the acetic acid 
is effected by volumetric analysis, and with some experience re- 
quires four to five minutes for its execution ; for the determina- 
tion of the alcohol an examination with the ebullioscope suffices, 
which can also be accomplished in four to five minutes.* These 

* The manner of executing these determinations will be described later on. 



118 VINEGAR, CID1 

two determinations, which every vinegar manufacturer should be 
able to make, are the only means of obtaining an accurate con- 
trol of the working of the factory, and also serve, of course, for 
settling the exact plan of operation from the start. 

If, with reference to the example given above, vinegar with 8 
per cent, of acetic acid is to be prepared, the alcoholic liquid 
must contain a total of 8.8 per cent, by weight of alcohol. Now 
if the fabrication is commenced with an alcoholic liquid contain- 
ing the total quantity of water, vinegar, and beer, but, for in- 
stance, only 5 per cent, by weight of alcohol, the following 
method will have to be pursued in order to accurately determine 
when and how much alcohol has to be added. 

The first portion of the alcoholic liquid being poured into the 
generator, the fluid running off is tested as to its content of acetic 
acid and alcohol, the test being repeated after the second and each 
successive pouring. Each test must show an increase in the con- 
tent of acetic acid and a decrease in that of alcohol, and the latter 
must finally have diminished so far that a new addition of alcohol 
seems to be in order. If the test after the third pouring shows 
the fluid to contain only 0.3 to 0.4 per cent, of alcohol, this 
quantity would be quickly and completely oxidized in the fourth 
pouring, and a certain quantity of acetic acid be at the same time 
destroyed. Hence it is necessary to add, for instance, 2 per cent, 
by weight of alcohol to the alcoholic liquid before the fourth 
pouring. When this 2 + 0.3 or 2-f 0.4 per cent, of alcohol, which 
the alcoholic liquid now contains, is again reduced after the sixth 
or seventh pouring to 0.3 or 0.4 per cent,, the last addition of 
1.8 per cent, of alcohol is made, the total quantity of alcohol, 
5 + 24-1.8 = 8.8 per cent, having now been used. 

When, after a certain number of pourings, a test of the fluid 
running off shows a content of 8 per cent, of acetic acid and only 
0.1 or 0.2 per cent, of alcohol (a small remnant of alcohol should 
always be present) the process is considered as finished, and a 
further pouring into the generator would not only be useless labor, 
but contrary to the end in view, since, after the complete oxida- 
tion of the last remnants of alcohol, that of acetic acid would 
immediately commence, and weaker vinegar would be obtained 
after each pouring. 



WORK IX A VINEGAR FACTORY. 119 

If a generator works up the quantity of alcoholic liquid in- 
tended for 12 or 15 hours in 10 or 12 hours, it is more proper, 
on account of the diminished loss by evaporation, to induce slower 
work by decreasing the draught of air in order to maintain the 
rule that a generator has to work up 3 liters (3.16 quarts) of 
absolute alcohol in the working time of a day. 

After controlling for several days the work of a generator, by 
examining the products as to their contents of acetic acid and 
alcohol, the plan of operation resolves itself from the results of 
these tests, since it is then accurately known after how many 
pourings of an alcoholic liquid of known composition an addition 
of alcohol is required ; further, after how many pourings a finished 
product is present, so that directions for the progress of the opera- 
tion can be given to the workmen according to time and quantities. 
The normal working of the generators can always be controlled 
by from time to time repeating the test of the products. 

Now, suppose the work in a newly arranged factory, having 
reached the point at which acidulation is complete, the actual 
fabrication, according to the old method, will be gradually com- 
menced by pouring in alcoholic liquid of corresponding concen- 
tration. 

The shavings in the generator having been saturated with 
acidulating vinegar, the latter is partially replaced by the fluid 
poured in, and as much as is expelled runs off. If the generator 
should at once commence to work regularly the temperature in 
its interior would be observed to rise, though it would at first be 
impossible to establish a change in the composition of the fluid 
running off. Slight variations in the content of acetic acid and 
a small percentage of alcohol could be determined in the fluid 
only after the acidulating vinegar originally present has been 
entirely expelled by a series of pourings. 

With the progress in the fabrication of vinegar, it became 
customary to produce the strongest vinegar possible, the so-called 
triple vinegar, with about 12 per cent, of acetic acid. On account 
of its greater commercial value, this article could be sent great 
distances, the consumer reducing it to a weaker product by the 
addition of water. 

To prepare directly vinegar with such a high percentage of 



120 VINEGAR, CIDER, AND FRUIT-WINES. 

acetic acid, it would, however, be necessary to acidulate all the 
generators with vinegar of the same strength, and to use alcoholic 
liquid very rich in alcohol. By this method the losses of alcohol 
by evaporation, and also of acetic acid, would, however, be so great 
as to make the product too expensive. Furthermore, the work 
would require most careful and constant attention on account of 
the difficulty with which oxidation takes place in alcoholic liquid 
containing much acetic acid, and it might only too readily happen 
that the generators suddenly worked weaker, i. e., that the content 
of acetic acid in the vinegar running off would decrease, and the 
quantity of alcohol remaining unchanged correspondingly increase. 

On account of these difficulties, it has become customary to 
charge the greater number of generators with alcoholic liquid 
yielding the so-called double vinegar with about 8 per cent, of 
acetic acid, and to work this vinegar with the addition of the 
required quantity of strong spirits of wine in a number of gen- 
erators, which, of course, must be acidulated with 12 per cent, 
vinegar. 

It will be readily understood that the employment of this 
method is not only advantageous for the production of vinegar 
with the highest attainable content of acetic acid, but also for 
general purposes. Passing the alcoholic liquid but once through 
the generators does not suffice, even for vinegar with only 5 to 
6 per cent, of acetic acid, an examination always showing a con- 
siderable quantity, J per cent, and more, of unconverted alcohol 
in the vinegar running off. The conversion of alcoholic liquid 
with a small content of alcohol into vinegar by one pouring can, 
to be sure, be accomplished, but it necessitates the use of very 
tall generators and a constant struggle with difficulties on account 
of the irregular draught of air, caused by the packing together of 
the shavings. 

Group-System. 

Theoretically, as well as practically, the group-system may be 
considered as the perfection of the quick process. The principle 
of the operation consists in the division of the generators into 
two or three groups, each group preparing vinegar of determined 
strength. In factories which do not produce vinegar of the 



WORK IN A VINEGAR FACTORY. 121 

greatest attainable strength (12 per cent, vinegar), but only 
double vinegar with about 8 per cent, of acetic acid, two groups 
might suffice ; the manufacture of a product of the greatest at- 
tainable strength being, however, advisable in most cases, it is 
recommended to arrange the factory for continuous work with 
three groups of generators. 

For this purpose the number of generators must be divisible 
by three; hence 3, 6, 9, 12, etc., generators have to be provided, 
of which 1, 2, 3, 4, etc., form one group, so that, for instance, in 
a factory working with 24 generators each group consists of 8. 
By designating the generators belonging to one group with the 
same number, we have groups I, II, and III, and in acidulating 
and operating the generators belonging to one group are treated 
in the same manner. 

For the preparation of the strongest vinegar (12 per cent.) the 
generators belonging to group I can, for instance, be acidulated 
with vinegar of 6 per cent, acetic acid, those of group II with 9 
per cent, vinegar, and those of group III with 12 per cent, 
vinegar. The process of operation is then as follows : 

Group I. The generators belonging to this group are charged 
Avith an alcoholic liquid which yields vinegar with a con- 
tent of 6 per cent, acetic acid, and the fluid running off is 
poured back into the generators until a test shows the 
alcohol, with the exception of a small remnant, to have 
been converted into acetic acid. To this vinegar is then 
added sufficient strong alcohol to form an alcoholic liquid 
which will yield 9 per cent, vinegar. 

Group II. The alcoholic liquid for 9 per cent, vinegar is 
poured into the generators belonging to group II, the 
pourings being repeated until all but a very small quantity 
of the alcohol is oxidized. The vinegar running off is 
again compounded with sufficient alcohol to form alcoholic 
liquid for 12 per cent, vinegar and is brought into 
Group III. The pourings are here repeated until the oxidation 
of the alcohol is nearly complete ; the finished product is 
then subjected to storing or clarification. 

As will be seen from the above, in operating according to the 
group system the entire factory is, so to say, divided into three 



122 VINEGAR, CIDER, AND FRUIT-WINES. 

factories, I, II, and III, of which I produces vinegar of 6 per 
cent., II vinegar of 9 per cent., and III vinegar of 12 per cent. ; 
the product of I, after having been converted by a suitable addi- 
tion of alcohol into alcoholic liquid adapted for the preparation 
of 9 per cent, vinegar, is directly used for charging the generators 
of group II and that of II for charging III. 

The generators belonging to one group having been acidulated 
with vinegar of the same strength, the fluid running off from one 
generator need not necessarily be returned to it. The work can, 
therefore, be simplified by conducting the fluid running off from 
all the generators by means of a suitable pipe-system into a 
common receiver instead of allowing the fluid, which has passed 
through a generator, to collect under a lath-bottom and then 
drawing it off and returning it to the same generator. If, for 
instance, 8 generators belong to one group and 3 liters (3.16 
quarts) have at the same time been poured into each, the passage 
of the liquid through all the generators will be shown by a 
measuring scale placed in the common receiver, indicating that 
the latter contains 3x8=24 liters (25.36 quarts). 

The samples for determining the content of acetic acid and 
alcohol are taken from the common receiver, and the latter also 
serves for the conversion of the vinegar, after it has acquired the 
percentage of acid attainable in that group, into stronger alcoholic 
liquid by the addition of alcohol. In order to effect an intimate 
mixture and at the same time prevent the vinegar ferment float- 
ing in the fluid from suffering injury by coming in contact with 
the highly concentrated spirits of wine, the required quantity of 
the latter is introduced in a thin jet and with constant stirring. 

In many factories it is customary from time to time to alter- 
nate with the pourings in the groups or "to cross the generators. 7 ' 
By this " crossing" the alcoholic liquid, which, according to the 
above method, would, for instance, pass from group II to group 
III, is poured into group I, so that after some time the gene- 
rators of this group are converted into generators of group III 
(with 12 per cent, acid), and group III becomes group I, it now 
containing the weakest alcoholic liquid (with 6 per cent. acid). 
Crossing, however, cannot be recommended, because a sudden 
change in the constitution of the nourishing fluid always exerts 



WORK IN A VINEGAR FACTORY. 123 

an injurious influence upon the augmentation of the vinegar 
ferment. 

Recourse to crossing is most frequently had for the purpose of 
" strengthening' 7 the vinegar ferment by working weaker alco- 
holic liquid in the generators of one group generally that which 
yields the strongest vinegar when their activity diminishes. 
This strengthening of the ferment can, however, be effected in a 
more simple and suitable manner by diminishing the quantity of 
alcoholic liquid poured in at one time and by increasing the 
draught of air, and the consequent change of temperature in the 
generators, so that the principal reasons for " crossing the gene- 
rators" (which many manufacturers consider indispensable) have 
no force. 



Group-System in Factories with Automatic Arrangements. 

In a factory so arranged that the pourings are at stated inter- 
vals effected by an automatic contrivance, the group system as 
described on p. 93 et seq. should be used. The operation of 
such a factory is very simple. As seen from the description of 
the arrangement, the generators are divided into three groups, 
I, II, and III. Besides the generators each group must be 
provided with a reservoir, which may be designated V, and a 
collecting vessel 8. (The other component parts, distributing 
arrangements, and conduits can here be left out of consideration.) 

For the production of 12 per cent, vinegar in such a factory it 
is best so to prepare the alcoholic liquid for the several groups 
that 

Group I contains alcoholic 

liquid with 6 p. c. acetic acid and 6.5 to 6.6 p. c. alcohol. 

Group II contains alcoholic 

liquid with .... 9 " " +3.2 to 3.3 

Group III contains alco- 
holic liquid with . . 12 " +3.2 to 3.3 

Group I having been acidulated with 6 per cent, vinegar, 
group II with 9 per cent, vinegar, and group III with 12 per 
cent, vinegar, the fluid running off from group I, after being 
compounded with 3.2 to 3.3 per cent, of alcohol, is used in group 



124 VINEGAR, CIDER, AND FRUIT- WINES. 

II as alcoholic liquid for 9 per cent, vinegar and yields 9 per 
cent, vinegar, which after being again compounded with 3.2 to 
3.3 per cent, of alcohol yields 12 per cent, vinegar after having 
passed through group III. 

The uninterrupted working of the generators constituting one 
of the principal advantages of the automatic system, it is advisable 
to regulate the automatic contrivance so that but a small quantity 
of alcoholic liquid be at one time poured out, and to fix the 
intervals between two pourings so that the second pouring takes 
pi aw after about one-half of the first has run off. Under these 
conditions there will be in the lower half of the generator an alco- 
holic liquid in which the alcohol is nearly as much oxidized as it 
can be by one passage through the generator, while in the upper 
half will be fresh alcoholic liquid in which oxidation is continued 
without interruption. A further advantage obtained by this is 
that a generator will yield quantitatively more than one working 
only 15 to 16 hours; further, the conditions of temperature in 
the interior of the generator remain always the same and the fer- 
ment constantly finds nourishment. 

The alcoholic liquid for group I is pumped into the reservoir 
I 7 ,, and passes through the generators of group I into the col- 
lecting vessel $,. All the alcoholic liquid having run off from V v 
the fluid collected in 8 V after having been tested as to its content 
of acetic acid, is for the second time pumped into V l and passes 
again through the generators of group I. The automatic con- 
trivance is so regulated that the alcoholic liquid, after being 
twice poured in, contains but a very small remnant of alcohol. 

To the vinegar of 6 per cent, collected in S l is now added 3.2 
to 3.3 per cent, by weight of alcohol, best in the form of 80 to 90 
.per cent, spirits of wine. The resulting stronger alcoholic liquid 
is at once pumped into V v and passing through the generators of 
group II reaches the collecting vessel 8 r It is then tested, 
pumpod back into V v and again collected in S 2 . If it now 
shows the required strength, it is mixed with the second portion 
of 3.2 to 3.3 per cent, by weight of alcohol and is pumped into 
T r s , and after passing twice through the generators collects as fin- 
ished vinegar in $ 3 . 

It will be seen from the above description of the process that in 



FABRICATION OF VINEGAR. 12o 

making the tests the product of all the generators of one group 
is treated as a whole. A disturbance may, however, occur in 
either one of the generators, and it would take considerable time 
before its existence would be detected by a change in the consti- 
tution of the entire product. The thermometer with which each 
generator is provided is, however, a reliable guide as to the ac- 
tivity of the latter, and if it shows in one of them a temperature 
varying 37 to 39 F. from that prevailing in the others, it is a 
sure sign of the respective generator not working in the same 
manner as the others, and the product running off' from it should 
be tested by itself as to its content of acetic acid and alcohol. 

Generally it will contain either no alcohol or very much of, it. 
In the first case, the temperature of the respective generator is 
higher than that prevailing in the others, and its activity has to be 
moderated by decreasing the admission of air ; in the other case, 
the generator works too sluggishly, and the difference is sought 
to be equalized by increasing the current of air or giving a few 
pourings of somewhat warmer alcoholic liquid. With a good 
heating apparatus producing a uniform temperature in the work- 
room such disturbances will, however, but seldom happen, and 
by the use of the above means the normal working of the gene- 
rators can be restored. 



CHAPTER XIII. 

DISTURBING INFLUENCES IN THE FABRICATION OF VINEGAR. 

IN no other industry based upon the process of fermentation 
are irregularities and disturbances of such frequent occurrence as 
in the fabrication of vinegar. Besides the nourishing substances 
dissolved in the fluid and free oxygen, the vinegar ferment re- 
quires a certain temperature for its abundant augmentation, by 
which alone large quantities of alcohol can in a short time be 
converted into acetic acid. By exercising the necessary care for 
the fulfilment of these conditions serious disturbances can be 



126 VINEGAR, CIDER, AND FRUIT- WINES. 

entirely avoided and the slighter ones due to insufficient acetous 
fermentation of the ferment readily removed. 

As regards the nourishing substances of the ferment, irregu- 
larities can actually occur only in working continuously with an 
alcoholic liquid composed exclusively of water and alcohol. In 
such alcoholic liquid the nitrogenous substances necessary for the 
nourishment of the ferment are wanting, nor are the phosphates 
present in sufficient quantity. The consequences are the same as 
observed in every insufficiently nourished fermenting organism : 
the fermenting activity suddenly diminishes, augmentation pro- 
ceeds sluggishly and ceases entirely if abundant nourishment is 
not introduced. Hence it may happen that from a generator 
containing alcoholic liquid composed only of water, alcohol, and 
vinegar, the greater portion of the alcohol suddenly runs off' un- 
changed, the temperature in the interior of the generator at the 
same time falling and the draught of air ceasing soon afterwards. 
When these phenomena appear it should first be ascertained 
whether the disturbance is not due to too slight a current of air. 
For this purpose the draught-holes are entirely opened, and if 
the temperature rises the generator gradually resumes its normal 
working. If, however, no improvement is observed, the disturb- 
ance is due to defective nourishment, and the composition of the 
alcoholic liquid has to be changed, which is best effected by the 
addition of a few per cent, of beer or of fermented alcoholic 
mash, both containing a sufficient quantity of phosphates and 
albuminous substances. The use of sweet beer wort or of malt 
extract has also been highly recommended for "strengthening 
weak-working generators." These substances also furnish albu- 
minous bodies and phosphates to the alcoholic liquid ; they also 
contain, however, maltose and dextrin, and as it has not yet been 
ascertained whether the latter and the carbohydrates in general 
can be consumed and digested by the ferment, they possibly may 
pass unchanged into the vinegar. Honey and glucose are also 
sometimes used for strengthening purposes, but while the former 
might be useful on account of the abundance of salts and nitro- 
genous substances it contains, no substances of any value to the 
ferment are present in the latter. At any rate the addition of 
beer, mash, or malt extract is to be preferred. 



FABRICATION OF VINEGAR. 127 

An addition of phosphates to the alcoholic liquid is also said to 
produce a favorable effect upon the augmentation of the ferment. 
Commercial solid phosphoric acid is dissolved in water and the 
solution neutralized with potassium, a solution of potassium phos- 
phate being obtained in this manner. The vinegar ferment being 
very sensitive towards this salt a very small quantity of the 
solution, about YTOIHJ of the weight of the alcoholic fluid, may be 
added. The experiment must, however, be made very cautiously 
and the effect upon the working of the generator carefully noted. 

Disturbances referable to the Quantity of newly formed Acetic Acid. 

With a proper state of working the alcoholic liquid brought 
into the generators should be completely converted into vinegar, 
and, theoretically, the product running off show the same strength 
as the vinegar used for acidtilation. Actually, there are, however, 
slight variations not exceeding a few tenths of one per cent. 
Should greater differences appear a disturbance actually exists 
and may show itself in various ways : the generator may work 
too feebly or too vigorously. In the first case the content of acetic 
acid in the fluid running off decreases considerably, while that of 
alcohol increases. The process of the formation of vinegar is, so 
to say, only half carried through, a great portion of the alcohol 
being converted, not into acetic acid, but into aldehyde. The 
greater portion of this combination is lost to the manufacturer on 
account of its low boiling point (71.6 F.), it escaping in the form 
of vapor, the stupefying odor of which when noticed in the air 
of the workroom is accepted by all manufacturers as indicative of 
a disturbance in the regular working of the generators. This 
odor, however, becomes perceptible only after the disturbance has 
continued for some time with the loss of a considerable quantity 
of alcohol. Hence the control of the working of the generators 
by a frequent determination of the acid becomes necessary. Re- 
peated observations of the thermometer also furnish valuable 
hints about the progress of the chemical process. The temperature 
in this case remains only for a short time unchanged and soon 
falls, far less heat being liberated in the mere conversion of alco- 
hol into aldehyde than when oxidation progresses to the formation 



128 VINEGAR, CIDER, AND FRUIT-WINES. 

of vinegar. These phenomena are indicative of the generator 
not being able to master the alcoholic liquid introduced and may 
be due to the pourings being too large, or the temperature of the 
alcoholic liquid poured in being too low, or finally to an insuffi- 
cient draught of air. 

To restore the generator to a proper state of working, it is best 
to try first the effect of smaller pourings and then an increased 
draught of air. If the disturbance was due to an insufficient 
draught of air, the temperature soon rises and the generator will 
be able to work up the regular quantity of alcoholic liquid. By 
the use of alcoholic liquid of a somewhat higher temperature the 
restoration of the normal conditions can be accelerated. 

A decrease in the content of acetic acid in the fluid running 
off from the generators without the presence of alcohol being 
shown indicates a too vigorous process of oxidation, the alcohol 
being not only oxidized to acetic acid, but the latter further into 
carbonic acid and water. The temperature in the interior of the 
generators rises considerably, about 45 F. above that of the 
workroom. 

In this case the restoration of the respective generator to a 
proper state of working is not difficult and can be effected in two 
ways : either by considerably decreasing the ventilation of the 
generator, or by pouring in a larger quantity of alcoholic liquid 
than previously used. 

The heating of the generators is generally due to faulty con- 
struction. Generators of large dimensions, as a rule, become too 
warm much easier than smaller ones, the phenomenon also appear- 
ing more frequently in summer than in winter; and "too warm" 
being just as injurious to the efficacy of the generators as " too 
cool," they must, during the warm season of the year, be as 
carefully protected against too high a temperature as against 
cooling during the cold season. This is effected, on the one hand, 
by a suitable ventilation of the workroom during the night, and, 
on the other, by the use of alcoholic liquid of a somewhat lower 
temperature during the hottest season of the year. Moreover, 
disturbances from too high a temperature of the exterior air need 
only be feared in countries with a very warm climate. 

It has been frequently proposed to counteract a too vigorous 



FABRICATION OF VINEGAR. 129 

activity of the generators by the addition of a little oil of cloves 
or salicylic acid which have the property of checking fermenta- 
tion. Salicylic acid, especially, is an excellent corrective for the 
faulty working of a generator ; it has to be used, however, with 
great caution and only be added by the T-Q JTF or f the weight of 
the alcoholic liquid and just in sufficient quantity to attain the 
desired result. A large amount is injurious to the ferment and 
might kill it. 

" Sliming" of the Generators. 

The phenomenon to which this term is applied belongs to a 
class of disturbances which sometimes occur in a vinegar factory, 
and whose progress generally ends in throwing the entire operation 
into complete disorder so that finally no more vinegar can be pro- 
duced. After fruitless experiments nothing remains but to empty 
the generators, wash the shavings with hot water, and, after drying 
and steeping them in hot vinegar, as in the commencement of the 
operation, return them to the generator. 

The evil begins to show itself by the generators commencing 
to work irregularly ; while formerly a certain quantity of alcohol 
was after a fixed number of pourings converted into acetic acid, 
a larger number of pourings are now required to attain the same 
result. The generators work slower and the heat in their interior 
decreases. By heating the workroom more strongly only a tem- 
porary improvement is brought about, and the production of the 
generators becomes less and less, and, finally, so low that work has 
to be interrupted. When the disturbance has progressed thus far a 
disagreeable musty, instead of the characteristic acid odor, is per- 
ceived in the workroom. By allowing one of the faulty working 
generators to stand for a few days without charging it with alco- 
holic liquid, the temperature in the interior may rise considerably 
and products of putrefaction be developed to such an extent as to 
taint the air of the workroom. 

Long before this phenomenon becomes apparent an alteration 

takes place in the shavings. A shaving taken from a normally 

working generator has the ordinary appearance of wet wood ; but 

one taken from a generator working in the above-mentioned 

9 



130 VINEGAR, CIDER, AND FRUIT-WINES. 

faulty manner is coated with a slimy mass, which is somewhat 
sticky and can be drawn into short threads. Viewed under the 
microscope this slimy coating presents a structureless mass, 
throughout which numerous germs of vinegar ferment are 
distributed and sometimes also vinegar eels. Independently of 
the presence of the latter, this slimy coating presents the same 
appearance as the so-called mother of vinegar. By placing a 
shaving coated with slime upright in a shallow dish and filling 
the latter f the height of the shaving with alcoholic liquid, the 
previously described delicate veil of vinegar ferment develops 
upon the surface, while the portion of the shaving covered by 
the fluid is surrounded by flakes distinguished by nothing from 
mother of vinegar. Hence there can scarcely be a doubt that the 
slimy coating actually consists of the same structure to which the 
term mother of vinegar (see p. 34) has been applied, and in 
searching for the cause of its formation, it will generally be 
found to be due to conditions similar to those which give rise to 
the formation of the latter. An alcoholic liquid overly rich in 
young beer containing much albumen, or one to which much 
malt extract or young fruit-wine has been added, is apt to give 
rise to the formation of mother of vinegar in the generators. 
The slimy coating thus formed upon the shavings envelops the 
vinegar ferment and prevents its immediate contact with the air ; 
consequently the alcoholic liquid does not encounter as much fer- 
ment as is required for the complete oxidation of the alcohol, and 
the generators become weaker. This decrease in the production 
is, of course, followed by a lower temperature in the generators 
and consequently by a decrease in the augmentation of the fer- 
ment, these unfavorable conditions finally becoming so great as 
to bring the activity of the generators to a standstill. 

The settlement of vinegar eels upon the surface of the mother 
of vinegar has no connection with sliming. Should, however, 
large masses of these animalcules happen to die in the generators 
for want of air, due to the constantly decreasing draught, they 
quickly putrefy on account of the high temperature and give rise 
to the most disagreeable smells. 

A careful manufacturer will observe sliming at the commence- 
ment of the evil, when it can be remedied without much diffi- 



FABRICATION OF VINEGAR. 131 

eulty. First of all, the composition of the alcoholic liquid must 
be changed by discontinuing the use of fluids containing many 
carbohydrates and albuminous substances, such as young beer, 
malt extract, young fruit-wine, etc., it being best to use alcoholic 
liquid of water, vinegar, and alcohol only until the generators are 
entirely restored to a normal working. The activity of the ferment 
is at the same time increased by a stronger draught of air in the 
generators and by raising the temperature of the workroom. In a 
few days the generators will be again in a proper state of work- 
ing, which is' recognized by the normal conversion of alcohol 
into acetic acid. 

If, however, the evil has progressed to a certain extent nothing 
can be done but to empty the generators. Though considerable 
labor is connected with this operation, there is no further use of 
experimenting, since such nonsensical additions as beer-yeast, 
tartar, honey, etc., which have been proposed as remedies, only 
accelerate the final catastrophe the entire cessation of the forma- 
tion of vinegar. Should a disturbance occur which cannot be 
accounted for by defective nourishment of the ferment, want of 
air, or an incorrect state of the temperature, the condition of the 
shavings should be at once examined into, and if they show the 
first stages of sliming the evil should, if possible, be remedied by 
changing the composition of the alcoholic liquid. If the new 
alcoholic liquid contains only water, vinegar, and alcohol sliming 
cannot progress, and the layers of slime upon the shavings will in 
a short time disappear, they being partially utilized in the nour- 
ishment of the ferment and partially mechanically washed off by 
the alcoholic liquid running down. 

Disturbances due to Vinegar Eels. 

In many factories filamentous structures scarcely visible to the 
naked eye will frequently be observed in the vinegar. When 
viewed under the microscope they will be recognized as animal- 
cules, to which the term vinegar eel (Anguilla acdi) has been ap- 
plied on account of their form slightly resembling that of an eel. 
Fig. 31 shows a microscopical picture of a drop of vinegar 



132 VINEGAR, CIDER, AND FRUIT- WINES. 

swarming with vinegar eels slightly magnified, and Fig. 32 
vinegar eel strongly magnified. 

Fig. 31. 




Drop of vinegar gwarming with vinegar eels, slightly magnified. 
Fig. 32. 




Vinegar eel (female) strongly magnified. 

The animalcule consists of a cylindrical body running to a 
sharp point. The mouth-opening is covered with small knots ; 
the throat is globular and passes directly into the long intestinal 



FABRICATION OF VINEGAR. 133 

tube. The eggs are placed at about the centre of the body in 
two tubes which unite to a plainly perceptible aperture. The 
average length of the female is 0.0682 Paris inch and that of 
the male 0.0486, the former being larger than the latter in the 
proportion of 1 : 1.3. 

Vinegar eels can exist in dilute alcohol of the strength used 
in the fabrication of vinegar as well as in dilute acetic acid. In 
alcoholic liquid containing much alcohol and acetic acid they do 
not thrive as well as in weak liquid. Their part in the fabrica- 
tion of vinegar is under all conditions an injurious one. The 
vinegar ferment can only carry on its function correctly when 
vegetating upon the surface of the fluid and in contact with air. 
The vinegar eel being an air-breathing animal always seeks the 
surface and in an alcoholic liquid which contains it and upon 
whose surface an abundance of ferment grows, actual contests 
between animalcule and ferment can be observed, the former 
striving to force the latter, which is inimical to its existence, 
under the surface and thus render it harmless. (Submerged 
vinegar ferment, as is well known, changes its conditions of ex- 
istence and becomes mother of vinegar.) If the conditions are 
favorable for the development of the animalcules, the latter over- 
come the ferment and submerge it so that it can continue to exist 
only as mother of vinegar, and consequently the process of the 
formation of vinegar will be considerably retarded. Under con- 
ditions favorable to the development of the ferment the reverse is 
the case. The ferment floating upon the fluid consumes nearly 
all the oxygen contained in the layer of air immediately above the 
surface and thus deprives the animalcules of a condition necessary 
for their existence ; a portion of them die and fall to the bottom 
of the vessel, while another portion escape to the sides of the vessel 
where they congregate immediately above the surface of the fluid 
in such masses as to form a whitish ring. These conditions can 
be readily induced by pouring vinegar containing a large number 
of vinegar eels into a flat glass dish and adding a fluid upon 
which vinegar ferment has been artificially cultivated. In a few 
hours the ferment has spread over the entire surface and the 
animalcules form the above-mentioned white ring on the sides of 
the vessel. If by means of blotting paper the veil of ferment be 



134 VINEGAR, CIDER, AND FRUIT-WINES. 

removed as fast as it augments, the animalcules soon spread over 
the entire fluid. 

From the above explanation it is evident that the appearance 
of vinegar eels in large masses threatens danger to the regular 
working. When the animalcules reach the shavings the struggle 
for existence between them and the ferment commences, and their 
struggling to dislodge the latter may be the first cause of the 
formation of slimy masses of mother of vinegar upon the shavings. 
Since the vinegar eels consume oxygen the air in the generators 
becomes thereby less suitable for the nourishment of the ferment 
and consequently the generators will work feebly. By accelera- 
ting the draught of air in the generators, which is generally the 
first remedy tried, the development of the ferment may again 
become so vigorous that a large portion of the vinegar eels are 
killed, their bodies being found in the vinegar running off. - The 
dead vinegar eels remaining in the generator, however, finally 
putrefy and give rise to the previously mentioned disagreeable 
odor. The processes of putrefaction being also effected by bacteria 
capable of decomposing nearly all known organic combinations 
(even small quantities of such strongly antiseptic bodies as salicylic 
and carbolic acids), it is evident that vinegar containing vinegar 
eels cannot possess good keeping qualities and must be subjected 
to a special treatment, which will be referred to later on. 

Several remedies for the suppression of vinegar eels in the 
generators have been proposed, one of them consisting of the 
introduction of vapors of burning sulphur, i. e. 9 sulphurous acid. 
Sulphurous acid, it is true, kills the vinegar eels but, at the same 
time, the vinegar ferment, and if small remnants remain, also the 
newly introduced ferment. To restore a generator thus treated a 
large quantity of air must be blown through it which will remove 
the last traces of sulphurous acid. An alcoholic liquid containing 
much living ferment is then poured in. 

The vinegar ferment can for many hours stand the exclusion of 
oxygen without being destroyed while the vinegar eels die in a 
short time. This circumstance may be utilized for the destruction 
of the animalcules without recourse to other remedies. The 
generator having first been brought into the highest state of 
activity by pouring in very warm alcoholic liquid and opening 



FABRICATION OF VINEGAR. 



135 



all the draught-holes, is left to itself for 6 to 8 hours after closing 
all the draught-holes. The ferment in a short time consumes all 
the free oxygen in the generators and the vinegar eels die from 
want of it. By opening the draught-holes and pouring in alco- 
holic liquid the normal formation of vinegar soon recommences. 

The killing of a large number of vinegar eels in the above 
manner is, however, of considerable danger to the regular work- 
ing of the factory, and the respective generators must be watched 
with special care in order to meet at once any appearance of 
putrefaction. It may sometimes succeed to keep up the work 
undisturbed, the killed vinegar eels being gradually removed 
from the generators by the vinegar running off. In such criti- 
cal cases, when the generator may at any moment commence to 
work irregularly, the use of a very small quantity of salicylic 
acid as an addition to the alcoholic liquid would be advisable. 
The acid by checking putrefaction would prevent the immediate 
decomposition of the killed vinegar eels still present in the 
generators. 

Should, however, signs of putrefaction appear energetic, means 
should at once be taken to arrest its progress, it being in this case 

Fig. ;33. 




Apparatus for the Development of Sulphurous Acid. 

best to sulphur the generator. This is effected by closing all the 
draught-holes except one, and introducing into the latter the 
nozzle of the apparatus whose arrangement is shown in Fig. 33. 
In a large clay vessel, best glazed inside, stands upon a tripod 



136 VINEGAR, CIDER, AND FRUIT- WINES. 

a flat plate. The cover of the vessel luted air-tight with clay is 
provided with three openings. The opening in the centre is 
closed by a well-fitting clay stopper, while glass tubes bent at a 
right angle and with a clear diameter of about J inch are 
cemented in the openings at the side. The tube reaching nearly 
down to the plate is connected by means of a rubber hose with a 
double-acting bellows, while the second tube leading directly from 
the cover is connected with a second clay vessel. From the cover 
of this vessel a pipe leads to, and is fitted into, the open draught- 
hole of the generator. 

For use the apparatus is put together, as shown in the illustra- 
tion, and small pieces of sulphur are thrown through the cen- 
tral aperture upon the plate. The sulphur is ignited by throw- 
ing in a lighted sulphur match, and after closing the aperture the 
bellows is put in operation. The product of the combustion of 
the sulphur passes through the tube into the generator, and as- 
cending dissolves the fluid adhering to the shavings to sulphurous 
acid. The addition of sulphur and blowing in of air are con- 
tinued until the odor of burning sulphur is clearly perceptible in 
the upper portion of the generator. The second vessel which 
contains some water serves for the condensation of the portion of 
the sulphur which is not consumed, but only volatilized. 

The sulphurous acid kills every living organism in the gene- 
rator, and consequently all the germs of the vinegar ferment are 
also destroyed. 

After allowing the sulphured generator to stand a few hours, 
fresh air alone is forced through it by means of the bellows ; the 
air-holes are then opened and the generator allowed to stand a 
few days for the sulphurous acid to be converted into sulphuric 
acid by the absorption of oxygen. To bring this generator again 
into operation it is best to introduce at first a number of pourings 
consisting only of vinegar, with a content of acetic acid corre- 
sponding to that of the original acidulation. In consequence of 
the absorption of sulphuric acid by the shavings this vinegar be- 
comes of no value as a commercial article, but it can be used for 
the preparation of alcoholic liquid. 

The last traces of unchanged sulphurous acid having in this 
manner been removed from the generators and the greater portion 



FABRICATION OF VINEGAR. 137 

of sulphuric acid adhering to the shavings washed out, the gene- 
rator is again acidulated ; this being best effected by pouring in 
alcoholic liquid just run off from normally working generators. 

Disturbances due to Vinegar Lice ( Vinegar- Mites). 

Unless the most scrupulous cleanliness prevails so-called vine- 
gar lice will always be found in the factory ; they prefer places 
kept constantly rnoist and to which the air has free access, for in- 
stance, the draught-holes and the interior of the generators be- 
neath the lath-bottom. As a rule manufacturers do not pay 
much attention to their presence, as they apparently exert no 
influence upon the regular working. That such, however, is not 
the case will be seen from the following occurrence : In 1881, the 
proprietor of a vinegar factory in Italy informed Dr. J. Bersch 
that millions of small animals had appeared in the factory and 
penetrated into the generators, the shavings up to a certain height 
being covered with living and dead animals, and the latter putre- 
fying, further working had become impossible. Every drop of 

Fig. 34. 




Vinegar-Mite, according to Bersch. X 120. 

vinegar running off from the generators contained one or more 
of the mites. A small bottle half full of vinegar and closed air- 
tight by a cork accompanied the communication. Though the 
bottle had been 60 hours on the way, on opening it a number of 



138 VINEGAR, CIDER, AND FRUIT- WINES. 

living animals were found congregated especially in the fissures 
of the cork. On examining them with the microscope two forms 
(male and female?) could be clearly distinguished, many being 
only one-quarter or one-half the size of others. Figs. 34 and 35 



Fig. 35. 




Vinegar-Mite (from the under side). X 120. 

show the two characteristic forms of these animalcules. As far 
as it was possible to determine their zoological position they be- 
long to the family Sarcoptidce. No particulars as to their origin 
seem to be known, the manufacturer simply stating that they 
had come from the soil under the supports of the generators and 
gradually rendered the latter ineffective. The generators were 
sulphured in the above-described manner and again put into 
operation. 

To prevent the vinegar-mites from collecting in large masses 
scrupulous cleanliness must prevail in the factory. Especially 
should the draught-holes be from time to time examined, and, if 
mites be found, thoroughly cleansed with hot water, which kills 
them. The mites might also be prevented from penetrating into 
the interior of the generators by rings of a sticky substance (tur- 
pentine) around the draught-holes. 



FABRICATION OF VINEGAR. 139 

Vinegar-Flies. 

Though, as far as known, the animals known as vinegar-flies 
create no disturbance in the regular working of the factory, they 
deserve mention because they appear wherever a fluid passes into 
acetous fermentation. In wine cellars, not kept thoroughly clean, 
these insects are frequently found on the bung-holes of the wine- 
barrels, and in factories in which the manufacture of wine vinegar 
is carried on according to the old system, they often occur in great 
swarms. 

The vinegar-fly (Drosophila funebris, Meig) is at the utmost 
0.11 inch long; it is especially distinguished by large red eyes 
sitting on both sides of the head and meeting in front. The 
thorax and legs are red, the abdomen which is provided with six 
rings, is black, with yellow stripes. The wings are longer than the 
body. The larva is white, has twelve rings, on the mouth two 
black hook-like structures, and on the back part of the body four 
warts two of which are yellow. In eight days the larva is trans- 
formed into a yellow chrysalis. 

The collection of these flies in large masses can be readily pre- 
vented by keeping the factory thoroughly clean and being espe- 
cially careful not to spill any fluid. 



CHAPTER XIV. 

METHOD OF THE FABRICATION OF VINEGAR IN APPARATUS 
OF SPECIAL CONSTRUCTION. 

To overcome the frequent disturbances in the working of a 
factory not provided with suitable heating and ventilating ar- 
rangements, several kinds of apparatus and methods have been 
proposed. Most of these inventions were protected by patent, 
but the relinquishment of the latter in a short time is the best 
proof of their non-success in practice. A few of them are here 
described, not because they are considered an essential pro- 
gress in the fabrication of vinegar, but simply as illustrations of 



140 



VINEGAR, CIDER, AND FRUIT-WINES. 



the manner in which the respective inventors sought to overcome 
the difficulties arising from the use of badly constructed appa- 
ratus. 

Singer's Vinegar Generator. 

Singer's apparatus consists of a number of shallow vats for the 
reception of the alcoholic liquid. These vats are connected with 
each other by a number of tubes so that the alcoholic liquid after 
it has risen to a certain height in one vat reaches the next one 
below and finally runs off as finished vinegar into a collecting 
vessel. 

Fig. 36. 




Singer's Vinegar Generator (Cross Section). 



Fig. 36 shows the apparatus in cross section. The five vats 
are marked A, A v B, B 19 and C. In the bottoms of A and A l 
are placed thirty-seven tubes, and in the bottoms of B and B, 



FABRICATION OF VINEGAR. 



141 



thirty-two. The entire apparatus is inclosed in a glass case pro- 
vided below with several apertures, n, with regulators, and above 
with a valve, m, by which the accurate regulation of the draught 
of air in the apparatus is to be effected. The rubber hose g se- 
cured to the reservoir E conducts at h the alcoholic liquid through 
the lid covering the uppermost vat A. In this vat the liquid 
rises to a certain height, runs through the apertures in the sides 
of the tubes into the vat J5, from this in a similar manner into 
A v B v and finally into the collecting vessel D. 

The process of the formation of vinegar is claimed to proceed 
in the tubes connecting the vats with each other. Fig. 37 shows 

Fig. 37. 




Singer's Apparatus (Connection of two Vats with each other). 

the arrangement of these tubes on an enlarged scale. The wooden 
tubes are closed above and provided each with four apertures for 
the influx of alcoholic liquid. Inside of each tube are six an- 



142 VINEGAR, CIDER, AND FRUIT-WINES. 

iiular depressions, four above and two below. In the centre is a 
slit for the access of air. 

To be able to discharge at will the fluid in one vat of the appa- 
ratus (Fig. 36) into the next below, the vats are connected by the 
pipe i closed by spigots. The lowest vat, C, is provided with 
discharge-pipes, I and k, I being directly above the bottom of 
the vat and k about 1J inch higher up. The collecting vessel D 
is at q connected by means of a rubber hose with the spigot <7 
placed on C. The glass tube p, which is bent at a right angle 
and can be turned, indicates, when in an upright position, the 
height of the fluid in D, and with the mouth turned downwards 
serves for discharging the contents of D. 

The apparatus is operated as follows : By opening the spigot 
E, alcoholic liquid is allowed to run from the reservoir into the 
uppermost vat, A, until it stands about J to } inch above the 
apertures in the tubes. The spigots on i remain closed during the 
normal working of the apparatus. The alcoholic liquid passes 
through the apertures, trickles through the tubes into the vessel, 
and gradually reaches in the same manner the collecting vessel 
D. By a suitable regulation of the influx of alcoholic liquid from 
E completely finished vinegar is claimed to collect in D. 

Michaelix's Rotatory Vinegar Generator. 

The principal feature of this apparatus, which has been patented 
in Germany, is a strong barrel placed horizontally and having a 
diameter of 3.3 feet and the same height. The interior of this 
barrel is divided into two chambers by a horizontal lath-bottom ; 
the upper smaller chamber is filled with shavings or pieces of 
charcoal. In the bottom below the lath-bottom a horizontal tube 
serves for the influx of air and a spigot above in the side of the 
barrel for its egress. 

The alcoholic liquid is poured in close under the lath-bottom, 
the air-spigot closed, and the barrel revolved so that the shavings 
become saturated. In about fifteen minutes the barrel is returned 
to its original position and the air-spigot opened. The commence- 
ment of the formation of vinegar is soon indicated by the increased 
temperature, and the apparatus is now in full working. To make 



FABRICATION OF VINEGAR. 143 

the- formation of vinegar a continuous one, it is only necessary to 
turn the barrel several times a day in order to saturate the shav- 
ings with alcoholic liquid. The progress in the formation of vine- 
gar is indicated by a thermometer placed in the bottom of the upper 
chamber. The end of the process is indicated by the falling of the 
thermometer. 

The apparatus is cleansed by rinsing the shavings, without re- 
moving them from the barrel, with hot water, filling the barrel 
with strong vinegar and drawing it off after 24 hours. 

According to the statements of the inventor, the advantages of 
his apparatus consist in its cheapness, simple operation, greater 
yield, saving of alcohol, and better quality of the product. 

It may, ho\vever, be remarked that the operation is not so 
simple, since every generator has to be several times turned 
daily, for which labor and space are required. How the appa- 
ratus, which works exactly like a generator filled with shavings, 
is to save alcohol and yield a greater product of a better quality 
cannot be explained from a chemical standpoint. Just as little 
can it be explained where the ferment indispensable for the 
formation of vinegar is to come from if the apparatus is to be 
cleansed with hot water, which kills all the ferment upon the 
shavings, and only strong vinegar is to be poured in. 

Fabrication of Vinegar with the Assistance of Platinum Black. 

In considering the theory of the formation of vinegar it was 
mentioned that finely divided platinum possesses the property of 
converting alcohol into acetic acid. This property of platinum 
black has been utilized for the purpose of manufacturing acetic 
acid on a large scale. The apparatus used is composed of a 
series of shelves about one foot apart, upon which rest a certain 
number of shallow dishes of porcelain or stoneware. In the 
centre of each of these and supported by stoneware or glass 
tripods rest smaller dishes containing the platinum black. The 
whole is covered with a glass case, if the apparatus is small, or a 
frame of wood with glass windows and glass top for the produc- 
tion of larger quantities of acetic acid. The air is made to cir- 
culate slowly through the apparatus, and the temperature main- 



146 



VINEGAR, CIDER, AND FRUIT-WINES. 



upwards. In front of the bung-hole this tube is provided with 
an expansion in which is fitted by means of a cork a tube, b, bent 
at a right angle. While the vinegar is stored, this tube stands 
upright as indicated by the dotted lines, and is secured to a rubber 



Pis. 38. 




hose reaching to the bung-hole. By turning the tube downward 
the fluid runs out through the tube a until its level has sunk to 
the dotted line. 

Sometimes the vinegar is not rendered entirely clear by storing^ 
and filtering has to be resorted to. Before referring to this ope- 
ration a few words will be said in regard to the storing of vinegar. 

The vinegar brought into the storage barrels contains the fol- 
lowing constituents : Water, acetic acid, alcohol (very little), alde- 
hyde (very little), acetic ether, vinegar ferment (living and dead), 
extractive substances (depending on the nature of the alcoholic 
liquid used). Moreover, there arc frequently found alcoholic fer- 
ment (from the beer) and vinegar eels and vinegar mites, if these 
animals exist in the factory. 

By filling the storage barrels to the bung-holes and closing 
them air-tight, the vinegar eels and vinegar mites die in a short 
time for want of air and fall to the bottom. The living vinegar 
ferment present in the fluid must assume the form in which it can 
for some time exist without free oxygen, i. e., of mother of vine- 
gar. When in consequence of the shrinkage in the volume of the 
vinegar by cooling the air penetrates through the pores of the 
wood, it is first utilized for the conversion of the small quantity 
of aldehyde into acetic acid, and later on enables the vinegar fer- 



TREATMENT OF FRESHLY-PREPARED VINEGAR. 147 

ment to continue to exist upon the surface and to slowly convert 
the small quantity of alcohol still present into acetic -acid. 

If the barrels are not closed absolutely air-tight, the vinegar 
ferment will develop quite vigorously upon the surface, and when 
all the alcohol is consumed attack the acetic acid, so that when 
the vinegar is tested a decrease in the content of acetic acid is 
plainly perceptible. If the finished vinegar still contains consid- 
erable quantities of albuminous substances in solution (vinegar 
from grain, malt, or fruit), or if it contains tartaric and malic acids 
and at the same time only a small percentage of acetic acid, as 
most fruit vinegars do (seldom more than 5 per cent.), the mold 
ferment readily settles upon the vinegar and finally dislodges the 
vinegar ferment from the surface. The acetic acid is, however, 
very rapidly destroyed by the mold ferment, and through a luxu- 
riant growth of the latter, which floats upon the surface as a 
white, membranous coating, the vinegar may in a few weeks lose 
one or more per cent, of it. This happens so frequently, for in- 
stance with fruit-vinegar, that the opinion that such vinegar cannot 
be made to keep, is quite general. 

Vinegar which, besides a considerable quantity of extractive 
substances, contains the salts of certain organic acids (malic and 
tartaric acids), for instance, vinegar prepared from apples or 
wine, must be frequently examined, as it readily spoils and may 
suffer even if kept in barrels constantly filled up to the bung. 
In fluids containing the salts of the above-mentioned organic 
acids a ferment may frequently develop, even when the air is ex- 
cluded, which first decomposes the 1 tartaric and malic acids, and 
though these acids are present only in a comparatively small 
quantity, they influence, to a considerable extent, the flavor of the 
vinegar on account of their agreeable acid taste. In vinegar in 
which this ferment has long existed a diminution of acidity can 
be readily detected by the taste, and by the direct determination 
of the acid a decrease in its content can be shown which, if cal- 
culated as acetic acid, may in some cases amount to one per cent. 
Besides the loss of its former agreeable taste vinegar thus 
changed acquires a harsh tang, due no doubt to the formation of 
certain not yet known products formed by the ferment effecting 
the destruction of the tartaric and malic acids. Moreover, wine 



146 



VINEGAR, CIDER, AND FRUIT-WINES. 



upwards. In front of the bung-hole this tube is provided with 
an expansion in which is fitted by means of a cork a tube, 6, bent 
at a right angle. While the vinegar is stored, this tube stands 
upright as indicated by the dotted lines, and is secured to a rubber 

> 
Fig. 38. 



I 




hose reaching to the bung-hole. By turning the tube downward 
the fluid runs out through the tube a until its level has sunk to 
the dotted line. 

Sometimes the vinegar is not rendered entirely clear by storing, 
and filtering has to be resorted to. Before referring to this ope- 
ration a few words will be said in regard to the storing of vinegar. 

The vinegar brought into the storage barrels contains the fol- 
lowing constituents : Water, acetic acid, alcohol (very little), alde- 
hyde (very little), acetic ether, vinegar ferment (living and dead), 
extractive substances (depending on the nature of the alcoholic 
liquid used). Moreover, there arc frequently found alcoholic fer- 
ment (from the beer) and vinegar eels and vinegar mites, if these 
animals exist in the factory. 

By filling the storage barrels to the bung-holes and closing 
them air-tight, the vinegar eels and vinegar mites die in a short 
time for want of air and fall to the bottom. The living vinegar 
ferment present in the fluid must assume the form in which it can 
for some time exist without free oxygen, i. e., of mother of vine- 
gar. When in consequence of the shrinkage in the volume of the 
vinegar by cooling the air penetrates through the pores of the 
wood, it is first utilized for the conversion of the small quantity 
of aldehyde into acetic acid, and later on enables the vinegar fer- 



TREATMENT OF FRESHLY-PREPARED VINEGAR. 147 

ment to continue to exist upon the surface and to slowly convert 
the small quantity of alcohol still present into acetic -acid. 

If the barrels are not closed absolutely air-tight, the vinegar 
ferment will develop quite vigorously upon the surface, and when 
all the alcohol is consumed attack the acetic acid, so that when 
the vinegar is tested a decrease in the content of acetic acid is 
plainly perceptible. If the finished vinegar still contains consid- 
erable quantities of albuminous substances in solution (vinegar 
from grain, malt, or fruit), or if it contains tartaric and malic acids 
and at the same time only a small percentage of acetic acid, as 
most fruit vinegars do (seldom more than 5 per cent.), the mold 
ferment readily settles upon the vinegar and finally dislodges the 
vinegar ferment from the surface. The acetic acid is, however, 
very rapidly destroyed by the mold ferment, and through a luxu- 
riant growth of the latter, which floats upon the surface as a 
white, membranous coating, the vinegar may in a few weeks lose 
one or more per cent, of it. This happens so frequently, for in- 
stance with fruit-vinegar, that the opinion that such vinegar cannot 
be made to keep, is quite general. 

Vinegar which, besides a considerable quantity of extractive 
substances, contains the salts of certain organic acids (malic and 
tartaric acids), for instance, vinegar prepared from apples or 
wine, must be frequently examined, as it readily spoils and may 
suffer even if kept in barrels constantly filled up to the bung. 
In fluids containing the salts of the above-mentioned organic 
acids a ferment may frequently develop, even when the air is ex- 
cluded, which first decomposes the" tartaric and malic acids, and 
though these acids are present only in a comparatively small 
quantity, they influence, to a considerable extent, the flavor of the 
vinegar on account of their agreeable acid taste. In vinegar in 
which this ferment has long existed a diminution of acidity can 
be readily detected by the taste, and by the direct determination 
of the acid a decrease in its content can be shown which, if cal- 
culated as acetic acid, may in some cases amount to one per cent. 
Besides the loss of its former agreeable taste vinegar thus 
changed acquires a harsh tang, due no doubt to the formation of 
certain not yet known products formed by the ferment effecting 
the destruction of the tartaric and malic acids. Moreover, wine 



148 VINEGAR, CIDER, AND FRUIT-WINES. 

or fruit-vinegars in which this ferment has for a considerable 
time flourished, lose their characteristic agreeable bouquet which 
may be considered the greatest damage. 

In the presence of a large number of vinegar eels their bodies 
may decay and impart to the vinegar a very disagreeable putrid 
odor, even if stored in barrels closed air-tight. 

The advisability of filtering the vinegar before bringing it into 
the storage barrels will be readily understood from the above state- 
ment. By filtration it is, however, only possible to remove the 
vinegar eels and vinegar mites swimming in the fluid and larger 
flakes of mother of vinegar. The ferments and bacteria inducing 
putrefaction cannot be thus removed, so that even filtered vinegar 
is liable to spoil when stored. 

Heating the Vinegar. 

In order to destroy all organisms which might cause the spoil- 
ing of the vinegar, it is recommended to heat the latter to about 
140 F. before running it into the storage barrels. A few 
moments exposure at this temperature being sufficient for the 
purpose, a large volume of vinegar can in a short time be heated 
with the use of a suitable apparatus, such as is shown in Fig. 39. 

In the head of the barrel b is secured a pipe of pure tin with 
very thin walls and a clear diameter of about J inch. It is 
coiled in a boiler filled with water, which it enters at e f and 
leaves at h. It then passes into the barrel 6, in which it is also 
coiled, and ends outside the barrel at g. At i it expands to a 
capsule in which a thermometer, t, is placed. A vat, a, placed at 
a certain height above the barrel is provided with a wooden stop- 
cock, c, to which is secured a rubber hose, d, which enters the 
barrel b above the bottom. The pipe k, which is secured on top 
of the barrel 6, is open on both ends and of sufficient length to 
project above the vat a. 

The boiler is filled with water and placed in an ordinary 
hearth. The vat a is filled with the vinegar to be heated and 
kept constantly supplied. The water being heated to boiling the 
stopcock c is opened. The vinegar now runs through d into the 
barrel 6, and, after filling it, flows at e into the tin coil and passes 



TREATMENT OF FRESHLY-PREPARED VINEGAR. 



149 



through it in the direction of the arrows, whereby it is heated. 
The thermometer t dipping into the hot vinegar indicates the 
temperature, and the influx of vinegar is accordingly regulated 
by opening or closing the cock c. As shown in the illustration, 

Fig. 39. 




Apparatus for heating Vinegar. 

the hot vinegar runs through the coil surrounded by cold vinegar 
into the barrel 6, whereby it is cooled off and the vinegar in the 
barrel preparatively heated. The pipe k, open on both ends, 
allows the escape of the gases developed. 

In consequence of the albuminous substances becoming insol- 
uble by heating, the vinegar running off at g is, as a rule, more 
turbid than before. It is brought into the storage barrels, which 
need, however, not be closed air-tight, the further processes taking 
place in the vinegar being of a purely chemical nature and not 
caused by organisms. The latter have been killed by heating, 
and, together with all other foreign bodies suspended in the 
vinegar, gradually fall to the bottom of the barrel. If the 
vinegar after heating is allowed to lie for a sufficiently long 
time, it clarifies completely and can be drawn off entirely bright 
from the sediment. 




OF 



150 



VINEGAR, CIDER, AND FRUIT- WINES. 

Filtration of the Vinegar. 



The bodies suspended in the vinegar and causing its turbidity 
being very small, it takes some time before they settle on the 
bottom and the fluid becomes entirely clear. To accelerate clari- 
fication the vinegar is filtered. 

Fig. 40 shows a filter suitable for the purpose. It consists of 
a small, strong wooden vat provided with two perforated false- 
bottoms, s and 6. Upon the lower false-bottom is spread a linen 
cloth and upon it fine sand which is not attacked by acetic acid, 
or small pieces of charcoal. Upon the smoothed surface of the 

Fig. 40. 




Filter for Vinegar. 

sand is spread a layer of paper pulp f to 1 inch deep which is 
covered with a linen cloth and then placed upon the false bottom 
6, the latter being forced down by means of the screw k and the 
pieces of wood r. The vinegar to be filtered is in the vat a which 
is connected with the filtering vat by the stop-cock h and the 
rubber hose s 8 to 10 feet long. By opening the stop-cock h the 
filter stands under the pressure of a column of fluid 8 to 10 feet 
high and the filtered vinegar runs off through an aperture in the 
side of the filtering vat. By filling the filter below the paper 



TREATMENT OF FRESHLY-PREPARED VINEGAR. 151 



Fig. 41. 



pulp with fine bar sand the latter retains the greater portion of 
the solid bodies suspended in the vinegar, and it will be a consid- 
erable time before the pores of the paper pulp become choked up 
to such an extent as to require its renewal. 

An arrangement suitable for filtering larger quantities of fluid 
under an increased pressure is shown in Fig. 41. 

It consists of a strong linen bag, S, about 16 inches in diameter, 
and a jute or hemp hose, JR, open at both ends and about 6 inches 
in diameter. The bag is tied by means of pack-thread to a 
cylindrical piece of wood which is secured to a suitable support. 
The bag is then connected by 
means of the rubber hose K 
with the reservoir B y which con- 
tains the vinegar to be filtered, 
and is placed about 10 to 13 
feet above the support carrying 
the bag. The bag is folded so 
that it can be inserted in the 
hose R, the latter being also se- 
cured to the cylindrical piece of 
wood. 

By slowly opening the stop- 
cock on the reservoir the bag is 
filled with vinegar, but being en- 
veloped by the hose R cannot en- 
tirely expand but only as far as 
permitted by the diameter of ft, 
so that though its entire surface 
acts as a filter a large number 
of folds are formed, .and it is 
thus protected from bursting 
even under the pressure of a 
column of fluid of considerable 
height. The fluid filtering 
through the bag runs down on 
the hose and collects in a vessel 
placed under it. 

At first this filter generally does not act entirely satisfactorily, 




Bag Filter for Filtering Vinegar under 
Pressure. 



152 VINEGAR, CIDER, AND FRUIT-WINES. 

the fluid running off turbid ; and this continues until the pores of the 
filter have become sufficiently contracted to retain the small bodies 
suspended in the fluid. This can, however, be remedied by stir- 
ring some charcoal powder into the first portion of vinegar to be 
filtered ; the charcoal powder adheres to the sides of the bag and 
contracts the pores of the tissue so that the fluid runs off entirely 
clear. 

By subjecting the freshly-prepared vinegar to heating and filter- 
ing, a commercial article is obtained which is perfectly clear and 
does not spoil by keeping. By storing it, however, for some time 
in barrels it gains considerable in fineness of odor and taste. 
AVine-vinegar, cider-vinegar and fruit-vinegars in general should 
positively be stored for some time, the odoriferous bodies which 
make these varieties so valuable developing only by that means. 

Sulphuring of Vinegar. 

Sulphuring has long been employed as the most convenient 
method for the preservation of wine, and, if correctly applied, can 
also be used for that of vinegar. But as sulphurous acid readily 
dissolves in vinegar the latter must not be brought in direct con- 
tact with the gases arising from the burning sulphur. 

The sulphuring of vinegar is best executed as follows : The bar- 
rel intended for the reception of the vinegar is thoroughly rinsed 
and immediately placed in the store-room. Then place a sulphur 
match consisting of a strip of linen about 6 inches long and f to 
1 inch broad dipped in melted sulphur, into a perforated sheet 
iron cylinder about 8 inches long and 1 inch in diameter, secure 
this cylinder to a wire, and after igniting the sulphur match lower 
it from the bnnghole to the centre of the barrel. The sulphurous 
acid formed by the combustion of the sulphur is at once dissolved 
by the water adhering to the interior of the barrel. A sulphur 
match of the above size suffices for a barrel of 100 to 125 gallons. 

Jf the sulphured barrel be now immediately filled with vinegar, 
the sulphurous acid becomes distributed throughout the fluid and 
kills the vinegar ferment as well as all other ferments present, so 
that the vinegar cannot undergo any further change except it 
come again in contact with living ferments. 



TREATMENT OF FRESHLY-PREPARED VINEGAR. 153 

The sulphurous acid dissolved in the vinegar is after some time 
converted into sulphuric acid and its presence can be readily de- 
tected. It may, however, be remarked that the quantity of sul- 
phuric acid reaching the vinegar in the above manner is an exceed- 
ingly small one, and, moreover, is partially fixed to the mineral 
bases (lime and magnesia) contained in the water used in the 
preparation of the alcoholic liquid. Hence a manufacturer who 
sulphurs his barrels need not fear being accused of having adul- 
terated his vinegar by the direct addition of sulphuric acid. 
Sulphured vinegar must be stored at least several weeks before it 
is salable, the odor of sulphurous acid adhering to it perceptibly, 
and disappearing only at the rate at which the sulphurous acid is 
converted into sulphuric acid. 

Fining of Vinegar. 

In a manner similar to that of wine, vinegar can be obtained 
bright by " fining" with isinglass. This method offers no advan- 
tages as compared with filtration, though it is employed by many 
manufacturers. The isinglass to be used is prepared as follows : 
One to two grammes (0.56 to 1.12 drachms) of isinglass per 
hectoliter (22 imp. gallons) are cut into narrow strips with the 
scissors and soaked in water in a porcelain dish for twenty- 
four hours. The jelly-like, nearly colorless mass is pressed 
through a linen cloth. A solution of 0.6 to 1.2 gramme (0.033 
to 0.067 drachm) of tannin per hectoliter (22 imp. gallons) is 
then added to the isinglass and the mass diluted with vinegar. 
The whole is then thrown into the barrel and thoroughly mixed 
with the contents. The clarified vinegar is finally drawn off 
from the sediment. 

Coloring Vinegar. 

Vinegar prepared from alcohol is either clear as water or only 
slightly colored. Before the general introduction of the quick 
process consumers were accustomed to the dark yellow product 
prepared from wine or beer, and many are still prejudiced against 
slightly-colored vinegar, considering it weaker. Unfounded as 



154 VINEGAR, CIDER, AND FRUIT-WINES. 

this prejudice is, the manufacturer is nevertheless obliged to re- 
cognize it and color his vinegar by artificial means. This is best 
effected by caramel or burnt sugar prepared from glucose, which 
is entirely harmless. It is best prepared by melting the glucose 
in a shallow iron vessel over a fire, stirring constantly with a 
long-handled spoon. The melted mass soon browns and rises in 
the vessel. The conversion of the sugar into caramel being much 
hastened in the presence of an alkaline body, 1J to 2 per cent, of 
the weight of the glucose used of pulverized ammonium carbonate 
is added at this stage. The mass is now heated with constant 
stirring until it becomes black, runs from the spoon in viscous, 
dark brown threads, and a sample dropped upon a cold surface 
congeals to a black mass impervious to light except on the edges. 
The vessel is then lifted from the fire and the contents poured out 
upon metal or stone plates. The taste of the congealed mass 
should not be bitter or at least only slightly so. On exposure to 
the air the caramel deliquesces to a thick black fluid, and, hence, it 
should immediately after its preparation be converted with water 
into a solution of the consistency of syrup, such concentrated solu- 
tion keeping better than a dilute one which easily molds. Im- 
mediately before use the solution is diluted with water, and enough 
of it added to the vinegar to give it the desired coloration. 



CHAPTER XVI. 

PREPARATION OF VINEGAR FROM VARIOUS MATERIALS. 

SINCE acetic acid is formed by the oxidation of alcohol, vine- 
gar can, of course, be prepared from every fluid containing alco- 
hol, such as beer, wine, cider, as well as from the juice of saccha- 
riferous fruits which has passed into alcoholic fermentation. By 
allowing grain to germinate, a body, to which the term diastase is 
applied, is formed which possesses the property of converting starch 
into fermentable sugar and dextrin when brought into contact 
with it under certain conditions. Vinegar can, therefore, be pre- 
pared from starch though in a round-about way by treating 



VINEGAR FROM VARIOUS MATERIALS. 155 

the latter with grain containing diastase (malt), whereby it is con- 
verted into maltose and dextrin. This fluid (sweet mash) is 
compounded with yeast, and the sugar (and with a correct execu- 
tion of the process the dextrin also) converted into alcohol by 
vinous fermentation. The resulting alcoholic liquid can then be 
used for the fabrication of vinegar. 

Alcohol or spirits of wine obtained in the above-described man- 
ner from the starch contained in potatoes or grain being at present 
the chief material used in the manufacture of vinegar, the greater 
portion of the latter brought into commerce might actually be 
designated potato or malt vinegar according to the elementary 
material used. The great progress made in modern times in the 
fabrication of malt, brewing of beer, and in the distilling industry 
has been accompanied by a constantly extending division of labor. 
While formerly every brewer and distiller prepared his own 
malt, there are at present numerous establishments exclusively 
engaged in this branch of the industry which sell their product 
to the brewer and distiller. The manufacturer of vinegar who 
did not use materials containing finished alcohol (beer or wine) 
had to undertake the laborious work of fabricating the malt, and 
preparing and fermenting the mash in order to obtain an alcoholic 
liquid which he could finally convert into vinegar. With the 
present improvements in the fabrication of malt and the distilling 
of alcohol, the vinegar manufacturer can work more cheaply by 
buying the alcohol, and the manufacture of so-called malt or 
grain vinegar would pay only where heavy taxes prevent the 
direct use of alcohol. 

Formerly, when, in consequence of defective processes, many a 
brewing or batch of malt spoiled it was used for the fabrication 
of vinegar. But, as a rule, the vinegar obtained was not of a 
fine taste and remained turbid, and besides the operation was fre- 
quently interrupted by all sorts of incidents, which led to the 
opinion of malt-vinegar not possessing keeping properties. 

Beer- wort judged by its composition does not seem a suitable 
material for the fabrication of vinegar. Besides a certain quantity 
of fermentable sugar (maltose), it contains a considerable amount 
of dextrin and other fermentable bodies. For the purpose of the 
fabrication of vinegar the maltose alone can be considered, it 



156 VINEGAR, CIDER, AND FRUIT-WINES. 

being the only fermentable constituent of beer-wort. Hence, 
vinegar prepared from beer-wort always contains a considerable 
quantity of dextrin and extractive substances, and, consequently, 
is of a more thickly-fluid nature than belongs to vinegar, and 
clarifies with difficulty. Moreover, this evil exerts a disturbing 
influence upon the behavior of the vinegar when stored, it being 
frequently changed by further processes of fermentation into a 
slimy fluid, and acquires an insipid taste and loses a large portion 
of its content of acetic acid. 

Alcoholic mashes containing in consequence of faulty preparation 
a considerable quantity of dextrin show, when used for the fabrica- 
tion of vinegar, a behavior similar to that of beer-wort ; the vinegar 
obtained clarifies with difficulty and does not keep well. Fer- 
mented whiskey-mashes properly prepared contain, how r ever, only 
very small quantities of dextrin and extractive substances, and, 
when freed by filtration from admixed husks, can be used as a 
material for the manufacture of vinegar and yield an entirely 
normal product. 

According to experience, the process of the formation of vinegar 
proceeds in the most uniform manner by preparing the alcoholic 
liquid from dilute alcohol, and, consequently, in a vinegar factory 
connected with a distillery it would be best to dilute non-rectified 
spirits of wine with the required quantity of water and add from 
10 to 20 per cent, of the weight of the alcoholic liquid of fer- 
mented mash. The latter containing salts and nitrogenous sub- 
stances suitable for the nourishment of the vinegar ferment serves, 
in this case, as a substitute for the beer generally used in vinegar 
factories for the preparation of alcoholic liquid. 

Manufacture of Vinegar from Malt and Grain. 

Under certain local conditions the manufacture of vinegar 
from malt, with or without an addition of grain, can be profi- 
tably carried on in connection with that of compressed yeast. 
Such factories being for evident reasons not established on an 
extensive scale, a description of the fabrication of vinegar in con- 
nection with that of compressed yeast without the use of expen- 
sive machinery will be given. 



VINEGAR FROM VARIOUS MATERIALS. 157 

The preparation of the fundamental material, malt, requiring 
much labor and knowledge, it will be best for the manufacturer 
to buy the article already prepared. Malt kiln-dried at as low a 
temperature as possible and yielding a light-colored extract when 
treated with warm water should be chosen. Many malt houses 
prepare such malt especially for distilling purposes. Malt pre- 
pared for brewing purposes is after the actual kiln-drying heated 
to a temperature frequently exceeding 158 F. for the formation 
of certain aromatic combinations and coloring substances which 
arc to impart to the beer a specific taste and dark coloration. 
Independently of the dark color of the vinegar prepared from such 
malt, it contains a considerable quantity of dextrin and conse- 
quently acquires an insipid by-taste, clarifies with difficulty, and 
is readily subject to injurious alterations. Malt, as is well known, 
contains diastase, which in mashing the malt with water effects 
the conversion of the starch into maltose and dextrin. By kiln- 
dry ing at a very high temperature a portion of the diastase is, 
however, rendered ineffective, and in mashing comparatively little 
maltose but a large quantity of dextrin is formed. Mashing, in 
this case, would have to be continued for a long time in order to 
obtain a larger quantity of maltose. 

With the use of but slightly kiln-dried malt, in which the effi- 
cacy of the diastase has not been injured by a high temperature, 
the greatest directly obtainable quantity of maltose and the 
smallest amount of dextrin are procured. The proportion of 
maltose to dextrin is in this case as 4 : 1, or, in other words, the 
finished mash contains about 80 per cent, of maltose and 20 per 
cent, of dextrin. The dextrin cannot be directly converted into 
acetic acid by the vinegar ferment and consequently would be 
found in the finished product. It is, however, possible to treat 
the finished mash in such a manner that the total quantity of dex- 
trin contained in it can be converted into maltose and the latter 
into alcohol. In this case the theoretically calculated yield of 
vinegar from the malt will be nearly approached in practice, and 
the product thus obtained contain only a small quantity of ex- 
tractive substances of the malt which are not decomposed by 
alcoholic or acetous fermentation. 

Before entering upon a description of the mashing process, 



158 VINEGAR, CIDER, AND FRUIT-WINES. 

the theoretical part in mashing will be briefly discussed. Malt 
contains starch and diastase. By bringing the comminuted malt 
in contact with water of about 131 to 133 F. the starch is 
formed into paste and the diastase passes into solution. By the 
action of the diastase upon the starch the latter is converted into 
maltose and dextrin, the finished mash containing 80.9 per cent, 
of maltose and 19.1 of dextrin. For reasons given later on the 
finished mash is heated for a short time to 140 to 140.8 F., 
without, however, exceeding this temperature, and then cooled off 
to the degree required for the induction of alcoholic fermenta- 
tion. 

Mash prepared in this manner contains, besides the stated quan- 
tities of maltose and dextrin, effective diastase, i. e., such as 
possesses the power of liquefying starch. (By heating to 1 above 
158 F. the diastase entirely loses this property.) By compound- 
ing a mash of this nature with yeast, the diastase with the simul- 
taneous action of the yeast is able to convert all the dextrin pres- 
ent in the fluid into maltose, and, consequently, the total quantity 
of starch originally present is converted into alcohol by this pecu- 
liar process to which the term after-effect of the diastase has been 
applied. 

The yield of acetic acid which can be obtained from a given 
quantity of malt can be calculated in a simple manner. Air- 
dried malt contains in round numbers about 68 per cent, of 
starch and dextrin. Theoretically 1 kilogramme of starch yields 
71.612 liter per cent, of alcohol ; in practice, however, only about 
55 liter per cent., and, after deducting a loss of 15 per cent, 
during the conversion of alcohol into vinegar, the quantity of 
acetic acid which can be actually obtained from a given quantity 
of malt can be determined. 

Example: What is the yield of 10 per cent, vinegar in working 
500 kilogrammes of barley malt? 

Five hundred kilogrammes of malt with 68 per cent, of starch 
(and dextrin) contain 340 kilogrammes of starch (and dextrin). 

Three hundred and forty kilogrammes of starch (and dextrin) 
give (with a yield of 55 per cent.) 18.700 liters per cent, of alcohol. 

One hundred and eighty seven liters of alcohol (specific gravity 
at 59 F. mm 0.795) are equal to 148.665 kilogrammes of alcohol. 



VINEGAR FROM VARIOUS MATERIALS. 159 

One hundred kilogrammes yield, according to theory, 130.4 kilo- 
grammes of acetic acid; in practice, after deducting a loss of 15 
per cent, during the formation of vinegar, 110.84 kilogrammes. 

148.665 kilogrammes of alcohol (15 per cent, of loss) yield 
164.78 kilogrammes of 100 per cent, acetic acid. 

164.78 kilogrammes of (100 per cent.) acetic acid yield in round 
numbers 1647 liters of 10 per cent, vinegar. 

The above calculation is, however, only approximately correct, 
as all the losses occurring in practice cannot be determined with 
complete accuracy. 

Unmalted grain being cheaper than malt and the latter contain- 
ing sufficient diastase to convert a very large quantity of starch 
into maltose and dextrin, a mixture of malt and unmalted grain 
(equal parts of both ; f grain and J malt, etc.) can be used instead 
of malt alone. The latter is, however, preferable for the manu- 
facture of vinegar, it yielding a product of a finer taste than un- 
malted grain. The mode of preparing the mash is exactly the 
same as for the distillation of alcohol, and as the necessary infor- 
mation can be obtained from any treatise on that subject only a 
brief sketch of the operation will be given here. 

The malt carefully ground is mixed with cold water to a thin 
paste which is stirred until all small lumps are dissolved. This 
mixing of the ground malt with water, or dougliing in as it is 
called, can be effected with the assistance of a crutch or rake, but 
best in a vat provided with a mechanical stirring apparatus. 

Doughing in being finished, water of 140 to 149 F. is per- 
mitted to run in until the mash shows a temperature of about 
131 to 133 F. During this operation the mash should be 
constantly stirred. The at first thickly-fluid mass will soon be 
observed to become thinly-fluid by the starch paste being con- 
verted into soluble bodies. Mashing is finished in 2 to 2J hours, 
and will be the more complete the more accurately the temperature 
is maintained at 131 to 133 F. The completion of the process 
is recognized by a filtered sample cooled to the ordinary tempera- 
ture remaining colorless after the addition of iodine solution. 

The mash having reached this state, sufficient hot water is added 
with constant stirring to raise the temperature to 140 or 141.8 F. 



160 VINEGAR, CIDER, AND FRUIT- WINES. 

The purpose of this operation is to render all ferments present in 
the mash ineffective. Lactic acid ferment and frequently also 
butyric acid ferment always adhere to the malt, and, if allowed to 
develop in the mash, would form lactic and butyric acids during 
fermentation which would be injurious to the process of alco- 
holic fermentation as well as to the properties of the vinegar to 
be manufactured. The mash is now reduced to a temperature of 
about 57 or 59 F. by bringing it into the cooling-back or pass- 
ing it through a system of refrigerating pipes. ' When working 
on a small scale the mash can be suitably cooled by allowing cold 
water to pass through a coil placed in the vat containing it. 

The strength of the vinegar to be manufactured depends on 
the concentration of the mash ; mashes showing a saccharometer 
statement of 20 per cent, contain after fermentation about 9J per 
cent, of alcohol which yields vinegar of about 8 per cent. ; mashes 
showing 18 per cent, yield vinegar of about 7 per cent., so that 1 
per cent, of acetic acid in the vinegar may be calculated on for 
about every 2J degrees indicated by the saccharometer. 

The mash is now set with yeast, though the latter may be added 
when the mash still shows a temperature of 71.5 to 75 F., the 
yeast having then time to vigorously augment. Mashes prepared 
from malt alone are uncommonly rich in nourishing substances 
for the yeast, the latter augmenting abundantly and inducing a 
very vigorous process of fermentation. This can be profitably 
utilized by combining the manufacture of vinegar and that of 
compressed yeast, a valuable product being thus obtained without 
any extra expense and with but little labor. At a certain stage 
of the alcoholic fermentation the yeast comes to the surface of the 
fluid and can be lifted off. By washing the yeast once or twice 
with cold water and then freeing it from the excess of water by 
pressing, compressed yeast is obtained which, with the exception 
of the portion to be used for setting fresh mashes, can be sold. 

Up to the completion of alcoholic fermentation the treatment 
of the mash, as can be seen from tho preceding description, does 
not essentially differ from that to which mashes for the manufac- 
ture of alcohol are subjected. If, however, the completely fer- 
mented "ripe" mash is to be used for the fabrication of vinegar, 



VINEGAR FROM VARIOUS MATERIALS. 161 

it should be subjected to a special treatment the object of which 
is to prepare a fluid containing no living yeast. 

By filtering the mash through a closely woven linen cloth the 
particles of malt-husks, etc., are retained but not the cells of alco- 
holic ferment which may be present and which, on account of 
their minuteness, are difficult to separate from the fluid by filtra- 
tion. It is, therefore, best to heat the mash before filtration to 
about 140 F. whereby the ferment is killed and at the same time 
a certain quantity of the albuminous substances dissolved in the 
fluid rendered insoluble and separated. The heating of the mash 
is best effected by passing it through a coil of tin-pipe placed in 
a boiler filled with water kept constantly boiling. The tempera- 
ture of the fluid can be readily regulated by increasing or decreas- 
ing the velocity with which it passes through the coil. If the 
fluid heated to 140 F. were allowed to cool in the air, a large 
portion of the alcohol contained in it would be lost by evaporation, 
and it is therefore allowed, after heating, to pass through a second 
coil of pipe which is surrounded by cold water whereby it is 
cooled to at least 86 F. This fluid is then filtered through a 
linen bag, it being repeatedly poured back into the filter until it 
runs off sufficiently clear. It will not, however, be obtained per- 
fectly cldar in this manner, the yeast cells being too minute to be 
retained by such a filter, but having been killed by heating, their 
presence in the fluid is connected with no disadvantage. 

By mixing the filtered fluid with from 10 to 15 per cent, of its 
volume of vinegar, an alcoholic liquid is obtained which can be 
worked in the usual manner in the quick-process generators, and 
yields an agreeable aromatic vinegar which clarifies rapidly and 
improves by storing. 

According to the slow process, the fermented malt-wort is run 
into casks placed in apartments called " stoves/ 7 since they are 
heated by stoves or steam at a temperature ranging from 70 to 
80 F. The casks are arranged in parallel rows, resting upon 
long wooden beams elevated about 18 inches from the ground, 
and having their bungs uppermost while a small hole on top of 
the front head of each causes the circulation of air. 

A large saving of labor will be effected by connecting elevated 
tanks holding the fermented wort with pipes and movable flexible 
11 



162 VINEGAR, CIDER, AND FRUIT-WINES. 

hose which will allow of the rapid and easy filling of the casks. 
The vinegar produced is siphoned off into inclined troughs, which 
deliver it to a central underground tank, from which it is 
pumped into the storing tanks. 

Malt vinegar generally contains a great deal of mucilaginous 
matter difficult to settle, preventing its keeping, while giving 
nourishment to vinegar eels. It is therefore necessary to filter it, 
and for this purpose it is pumped into the refining or rape ves- 
sels. These vessels are often filled with wood shavings, straw, or 
.spent tanner's wood, but nothing acts so well in producing by 
filtration a clear bright vinegar as the stalks and skins of grapes 
or raisins technically called " rape." Where there is power and 
a large quantity of vinegar is manufactured, the filtering is effected 
under a considerable hydrostatic pressure. The rape is placed in 
a closed vessel between two false perforated bottoms. A circuit 
of pipes is connected at the lower and upper part of the vessel, 
and by means of a pump the vinegar is made to pass again and 
again through the rape. 

This mode of manufacture is frequently effected by " fielding." 
In this case, as the term implies, the process is conducted in the 
open air. The casks rest on strong frames 1J feet high, being 
supported by firm pillars of brick-work or wood. The operation 
generally begins in spring and continues during the summer. 
The fermented liquor is run into the casks by the bung-holes, 
the latter being left open in dry and loosely covered with a tile 
in wet weather. Gradually the alcohol of the "gyle," as the fer- 
mented liquor is called, becomes oxidated, and acetic acid is pro- 
duced, of course simultaneously affording vinegar. The latter is 
then drawn off and transferred to the refining or rape vessels 
where it passes through the process of filtration already described. 
In some factories large quantities of sour ale and beer are con- 
verted by similar processes into vinegar, but the product is much 
inferior to the vinegar made from malt-wort. The large amount 
of nitrogenous and other extractive substances which those liquids 
contain undergoes a second or putrid fermentation after the 
alcohol has been oxidized into acetic acid, and in doing so reacts 
upon the acid, leaving a liquid of a disagreeable odor slightly re- 
sembling very stale beer. By the addition of sulphuric acid this 



VINEGAR FROM VARIOUS MATERIALS. 163 

second fermentation is postponed for some time, but the vinegar 
has nevertheless a nauseous smell which renders it objection- 
able. 



Preparation of Vinegar from Sugar-Sects. 

The juice of the sugar-beet contains a considerable quantity of 
cane sugar and is readily brought into alcoholic fermentation, so 
that seemingly this root would form a very suitable material for 
the fabrication of vinegar. Sugar-beets contain on an average 12 
per cent, of cane sugar, the latter yielding, when completely fer- 
mented, a fluid containing about 6 J per cent, by weight of alcohol ; 
a fluid with this percentage of alcohol yields vinegar with 6 per 
cent, of acetic acid. 

Besides sugar the juice of the beet-root contains, however, a 
large number of other substances which exert an influence upon 
the course of alcoholic fermentation, and, besides alcohol, a large 
quantity of fusel oils is formed so that the alcohol has to be 
thoroughly rectified before it is fit for use. The fermented beet- 
root juice itself has, however, a disagreeable taste and odor, and 
the vinegar prepared from it showing similar properties will not 
be fit for household purposes until a remedy for these evils is 
found. Numerous experiments made for the purpose of freeing 
beet-root vinegar from the substances which impart to it the dis- 
agreeable odor and taste have given no favorable results; filtering 
through charcoal and even distilling the vinegar and treating the 
distilled product with strongly oxidizing bodies do not produce the 
desired effect. From these experiments it would seem impossible 
to directly obtain from sugar-beets vinegar fit for household use. 

Vinegar from Sugar, Fruits, and Berries. 

By fermenting sugar solution with pure yeast and pouring off 
the clear alcoholic fluid, the latter shows a slightly acid reaction 
(from succinic acid), but is not converted into vinegar even if 
standing for several weeks in the most suitable temperature, be- 
cause the vinegar ferment is wanting. By adding, however, an 
excess of yeast so that it remains partially suspended in the fluid, 



164 VINEGAR, CIDER, AND FRUIT- WINES. 

which can be effected by the addition of solution of gum or starch 
past.e, the nourishment for the spores of the vinegar ferment 
reaching the fluid from the air is provided and acetification takes 
place. 

Cadet-Gassicourt advises the fermentation together of 124 
parts of sugar, 868 of water, and 80 of yeast, and to filter after 
one month. Or, according to another formula : sugar 245 parts, 
gum 61, water 2145, yeast 20. Allow to ferment at 68 F. 
Fermentation begins the same day and is completed in 1 5. 

Doebereiner gives the following directions : Dissolve 10 Ibs. of 
sugar in 180 quarts of hot water, add 6 Ibs. of pulverized crude 
tartar (it dissolves only partially), and after cooling to 77 F. 
induce fermentation by 4J quarts of beer yeast. In about 8 
days, when fermentation is finished, add about 15 quarts of 
spirits of wine of at least 50 per cent. Tr. or 8 quarts of alcohol 
of 90 per cent, Tr., and bring the mixture into the acetifying 
vessel. This fluid would also be suitable for the quick process. 

For making vinegar on a small scale for domestic use, brown 
sugar with water alone, or sugar with raisins, currants, and espe- 
cially ripe gooseberries, may be used. These should be mixed in 
the proportions which would give a strong wine, put into a small 
barrel filled to about three-fourths of its capacity, with the bung- 
hole very loosely stopped. Some yeast should be put in and the 
barrel set in the sun in summer or a little way from the fire in 
winter, and fermentation will soon begin. This should be kept 
up constantly, but moderately, till the taste and smell indicate 
that the vinegar is complete. It should then be poured off clear, 
and bottled carefully. It will keep much better if it is boiled 
for a minute, cooled, and strained before bottling. 

With the exception of apples and pears, the different varieties 
of fruit cannot be had in such abundance as that they could be 
used for the manufacture of vinegar on a large scale, and hence 
only a brief description of their utilization for that purpose will 
be given. 

It is characteristic of most of our varieties of fruits, and espe- 
cially of berries, that in proportion to their content of sugar they 
have a much greater content of free acids than grapes, and this 
circumstance must be taken into consideration, as otherwise wine 



VINEGAR FROM VARIOUS MATERIALS. 165 

would be obtained which contains a considerable quantity of 
unfermented sugar. The following table shows the average 
content of sugar and free acid in the most common varieties 
of fruits : 



Free acid calculated 


Sugar. as malic acid. 


Cherries 


. 10.00 





Apples .... 


. 6.25 to 13.99 


0.691 


Pears .... 


. 8.78 







6.40 


2.147 


Strawberries . 


. 5.09 to 11.31 


1.363 


Gooseberries . 


. 6.93 


1.603 


Bilberries 


. 5.78 


1.341 




4.02 


1.484 


Blackberries . 


4.44 


1.188 



According to the above table, currants, gooseberries, raspber- 
ries, etc., contain on an average scarcely 6 per cent, of sugar, and 
consequently their juice, after complete fermentation, would give 
a fluid with about 3 per cent, of alcohol, from which vinegar 
with about 2J per cent, of acetic acid could be obtained. Such 
vinegar being, however, too weak, those berries would not seem 
suitable for the direct preparation of vinegar. Moreover, the 
complete fermentation of the juice of most berries is very diffi- 
cult, the free acids, among which malic acid preponderates, ex- 
erting an injurious influence upon the progress of fermentation. 

Vinous .fluids of an agreeable taste can, however, be prepared 
from berries, and from them an aromatic and finely flavored 
vinegar, by decreasing the content of acid in the juice and in- 
creasing that of sugar. The juice of currants, as seen from the 
above table, contains in round numbers 6 per cent, of sugar and 
2 per cent, of malic acid. By diluting this juice with an equal 
volume of water a fluid containing 3 per cent, of sugar and 1 per 
cent, of acid is obtained, and the content of the former can be in- 
creased at will by the direct addition of sugar. 

By compounding, for instance, 100 quarts of currant juice with 
100 quarts of water and adding 34 Ibs. of sugar, the resulting 
fluid contains about 20 per cent, of sugar and after complete fer- 
mentation gives a fluid with about 9.5 per cent, of alcohol, which 
yields vinegar of nearly 9 per cent, strength. The taste of this 



166 VINEGAR, CIDER, AXD FRUIT-WINES. 

vinegar is, however, stronger and more agreeably acid than that 
of vinegar from alcohol, it containing besides acetic acid about 1 
per cent, of malic acid. Moreover, vinegar obtained from ber- 
ries contains a certain quantity of extractive substances and odor- 
iferous products of fermentation, so that it possesses an agreeable 
bouquet and thus appears more valuable than the ordinary pro- 
duct. 

In many regions bilberries grow in abundance and can be 
bought very cheap. Treated in the above manner they yield an 
excellent vinegar, possessing, however, a somewhat harsh by-taste, 
due to the tannin contained in the berries. The latter can be re- 
moved from the fermented fluid before using it for the prepara- 
tion of vinegar by compounding it when quite clear with gelatine 
solution or fresh white of egg, both forming insoluble combina- 
tions with the tannin, which separate in the form of flakes. 

In regard to the preparation of vinegar from berries it remains 
to be remarked that, after pressing the bruised berries, the juice 
is compounded with water and sugar and at once brought into 
fermentation by the addition of yeast (best fresh wine-yeast, or 
if this be wanting, compressed yeast divided in water). Fermen- 
tation should take place at quite a high temperature, 68 to 72 
F. The separated yeast is carefully removed from the fermented 
liquid and the latter stored away in barrels kept constantly filled 
up to the bung or at once used for the preparation of vinegar. 
By converting fruit-wine into vinegar by means of the vinegar 
ferment floating upon the fluid a much finer product is obtained 
than by the quick process. 

Cider Vinegar. 

Cider, as is well known, is the sparkling liquid which is pre- 
pared by fermenting the juice of apples ground in a mill. The 
manufacture of cider will be described in another portion of this 
work, and, hence, only its utilization for the preparation of vine- 
gar will be given here. 

The preparation of vinegar from good cider is not difficult, the 
process of acetification by means of the vinegar ferment floating 
upon the surface yielding an aromatic product of a fine flavor 



VINEGAR FROM VARIOUS MATERIALS. 167 

which is nearly of as good a quality as wine vinegar. On ac- 
count of its content of malic acid, the vinegar is more acid than 
ordinary vinegar with the same content of acetic acid. But in 
order to produce cider vinegar of the first quality one must have 
good cider ; vinegar made of watered cider will be thin and weak. 
S. E. Todd* describes a simple contrivance for making cider 
vinegar. A kind of cupboard is made of inch boards about 3J 
feet high by seven feet long. Inside of this box fit shelves about 
3J inches apart. On the upper side of these shelves gouge out 
channels running nearly from one end to the other until the 
upper side is covered with zigzag grooves running from end to 
end. There should be cleats fastened to the under side of each 
shelf to prevent it from warping ; and the cleats should be put 
on with screws. The channel must be made slightly slanting. 
The top shelf must slant so as to be about two inches lower than 
the other side, and the shelf below it should slant about two 
inches in the opposite direction. By this arrangement a long 
zigzag channel is made for the liquid to flow in. At its end, in 
the upper shelf, bore a hole through so that the vinegar may drop 
to the next shelf and traverse the channel. Thus it continues to 
flow from end to end until it has reached the end of the channel 



in the lower shelf, when it falls into a receptacle. When com- 
mencing to make vinegar in this manner, place the apparatus in 
some small room and keep the temperature about 90 or 95 F. 
Have a barrel, or tub, or hogshead placed a little higher than the 
box and near the end where the first channel commences in the 
top shelf. In this barrel have a faucet so that you can regulate 
the amount of cider which it is designed to have flow in the 
channel. The aim should be to keep a very small stream moving 
gently through the apparatus, aifording every drop ample time 
and opportunity to absorb the desired amount of oxygen before 
the liquid reaches the end of the channel in the last shelf. A 
few gallons, or a half barrel of good strong vinegar should be 
run through first, so that the shelves will be well acidulated be- 
fore letting other mixtures run through. It is a good idea to 
add one-third or one-fourth of good vinegar to any mixture of 

* " The Apple Guitarist." New York, 1871. 



168 VINEGAR, CIDER, AND FRUIT-WINES. 

eider before allowing it to run through the apparatus. Open the 
faueet so that a stream not larger than a straw shall fall into the 
channel of the top shelf. As it falls through the last hole into 
the barrel placed below the apparatus, the cider will have changed 
to strong and pure vinegar. When once started the process must 
continue night and day until the supply fails. In warm weather 
no fire will be required in the vinegar apartment, which should be 
well supplied with fresh air to facilitate oxidation. If the liquid 
is allowed to flow too rapidly, it will not have time to oxidize. 

Vinegar from apple-pomace. After the cider has been ex- 
tracted and the cheese removed from the press, the pomace may 
be placed in a pile upon a suitably-constructed platform and al- 
lowed to ferment. In the course of a few days considerable heat 
will be evolved ; at this time a few pails of warm water (not boil- 
ing) should be poured upon the pile and in the course of twenty- 
four hours the pomace will be in a proper condition to grind. It 
should then be run through a grater-mill and relaid upon the press 
in a cheese in the same manner as originally laid in cider making, 
when it may be subjected to heavy pressure until the liquid con- 
tained in the cheese be extracted. This liquid may then be ex- 
posed in shallow open casks in a warm room and in a short time 
will be found good vinegar. Or, the liquid may be immediately 
passed through a generator. 



CHAPTER XVII. 

PREPARATION OF VINEGAR SPECIALTIES. 

THESE specialties may be divided into two groups : into those 
with a specific odor, and those with a specific odor and taste. As 
an example for both kinds we will take tarragon (dragon's-wort) 
vinegar. If it is prepared by simply dissolving in the vinegar 
the volatile oil of dragon's-wort (Artemisia dracunculus), obtained 
by distillation with water, the product is simply perfumed vinegar, 
the odor of the volatile oil being mixed with that of the acetic 
acid, but the taste remains unchanged. If, however, the fresh 



PREPARATION OF VINEGAR SPECIALTIES. 169 

leaves of the plant are macerated with vinegar, not only the vola- 
tile oil is dissolved but also certain extractive substances peculiar 
to this plant, and the taste of the vinegar is also changed ; the 
product in this case being aromatized vinegar. 

By dissolving in vinegar oil of roses or rosewater (perfumed) 
rose vinegar is obtained ; by treating raspberries with vinegar the 
latter absorbs not only the odoriferous substances of the rasp- 
berries, but also the non-odoriferous extractive substances, and the 
product is aromatized vinegar. 

By skillful manipulation every volatile oil can be dissolved in 
vinegar, and consequently as many different varieties of perfumed 
vinegar can be prepared as there are volatile oils. In fact per- 
fumers prepare a number of such varieties which contain one or 
more volatile oils whose odors harmonize and are sold as volatile 
spirit of vinegar, fumigating vinegar, etc. Such vinegars can be 
prepared in various ways, the finest odors being, however, ob- 
tained by distilling the fresh parts of the plants with water and 
mixing the distillate, which actually represents a solution of the 
volatile oil in water, with strong vinegar. The finest rose vinegar, 
orange blossom vinegar, etc., are prepared in this manner. 

For this rather tedious process of preparing perfumed vinegar, 
the one in which freshly prepared volatile oils are used may be 
advantageously substituted. To be sure the volatile oils dissolve 
only sparingly in vinegar, but sufficiently so to impart their char- 
acteristic' odor to it. By using an excess of volatile oil it does 
not dissolve, but distributes itself in fine drops throughout the 
vinegar, rendering the latter opalescent, so that fining with tannin 
and isinglass is necessary to make it bright again. 

This evil can be avoided by a simple manipulation which is 
based upon the fact that a body dissolving with difficulty dissolves 
the more readily the greater the surface it offers to the solvent. 

Prepare glass-powder as fine as the best wheat flour by heating 
pieces of glass, throwing them into cold water, and pulverizing 
and elutriating in a mortar. By the sudden cooling the glass 
becomes so brittle that it can be readily converted into a fine 
powder. Bring a suitable quantity of this powder into a porcelain 
dish and drop volatile oil upon it with constant rubbing until it 
is uniformly moistened. Pour the vinegar to be perfumed upon 



170 VINEGAR, CIDER, AND FRUIT-WINES. 

this glass powder and stir gently with the pestle. The fluid is 
then poured into the barrel intended for the reception of the per- 
fumed vinegar and a fresh quantity of vinegar poured upon the 
glass-powder, this being continued until all the glass-powder has 
been brought into the barrel by stirring and pouring over fresh 
vinegar. The barrel is then entirely filled with vinegar, and after 
'being closed, rolled in order to effect a uniform mixture of its 
contents. It is then allowed to rest for a few days for the glass- 
powder to settle. The entirely clear perfumed vinegar is then 
drawn off into bottles, which are to be kept in a dark cool room, 
the odor of the volatile oil being injured by light and heat. 

For the preparation of volatile fumigating or toilet vinegars it 
is best to dissolve the volatile oils in uncolored vinegar prepared 
from alcoholic liquid. Where the remaining of a small residue 
after the volatilization of the perfumed vinegar is of no impoft- 
tancc, pulverized sugar may be substituted for the glass powder, 
as it acts in the same manner ; the only difference is that the 
glass-powder being an insoluble body falls to the bottom of the 
barrel, while the sugar dissolves together with the volatile oil in 
the vinegar. 

By the above-described process perfumed vinegars with the 
odor of dragon's- wort, peppermint, anise, rose, etc. etc., may be pre- 
pared, and by a suitable mixture of those whose odors harmonize 
a great number of fumigating and toilet vinegars. 

The preparation of aromatized vinegars by means of the extrac- 
tive substances of plants is very simple. The parts of plants to 
be extracted are placed in a suitable vessel, a barrel or large flask, 
and after pouring vinegar over them and closing the vessel, are 
allowed to rest for a few weeks in a moderately warm room. In 
rase glass vessels are used they have to be kept in a dark room, 
light exerting an injurious influence upon the odors. The vege- 
table substances used for aromatizing vinegar containing, as a 
rule, a large quantity of water, strong vinegar (with 10 to 11 per 
cent, acetic acid) should be used. 

In the following a few formulae for toilet and table vinegars 
are given : 



PREPARATION OF VINEGAR SPECIALTIES. 171 

Toilet Vinegars. 

Mohr's volatile spirits of vinegar. Equal parts of acetic acid 
and acetic ether perfumed with a few drops of oil of cloves. 

Aromatic vinegar. Concentrated acetic acid 8 ounces, oil of 
lavender 2 drachms, oils of rosemary and cloves each 1 drachm, 
oil of camphor 1 ounce. 

First dissolve the bruised camphor in the acetic acid, then add 
the perfumes ; after standing for a few days with occasional agi- 
tation it is strained and is then ready for use. 

Henry's vinegar. Dried leaves of rosemary, rue, wormwood, 
sage, mint, and lavender flowers each 1 ounce, bruised nutmeg, 
cloves, angelica root and camphor, each J ounce, alcohol (rectified) 
8 ounces, concentrated acetic acid 32 ounces. 

Macerate the materials for a day in the alcohol ; then add the 
acid and digest for a week longer at a temperature of about 59 F. 
Finally press out the now aromatized vinegar and filter it. 

Vinaigre des quatre voleurs. Fresh taps of common wormwood, 
Roman wormwood, rosemary, sage, mint and rue each f ounce, 
lavender flowers 1 ounce, garlic, calamus aromaticus, cinnamon, 
cloves, and nutmeg each 1 drachm, camphor J ounce, alcohol or 
brandy 1 ounce, strong vinegar 4 pints. 

Digest all the materials, except the camphor and spirit, in a 
closely covered vessel, for a fortnight, at summer heat ; then 
express and filter the vinegar produced and add the camphor 
previously dissolved in the brandy or alcohol. 

Hygienic or preventive vinegar. Brandy 1 pint, oils of cloves 
and lavender each 1 drachm, oil of marjoram J drachm, gum 
benzoin 1 ounce. 

Macerate these together for a few hours, then add 2 pints of 
brown vinegar and strain or filter. 

Cosmetic vinegar. Alcohol 1 quart, gum benzoin 3 ounces, 
concentrated aromatic vinegar 1 ounce, balsam of Peru 1 ounce, 
oil of neroli 1 drachm, oil of nutmeg J drachm. 



172 VINEGAR, CIDER, AXD FRUIT- WINES. 

Table Vinegars. 

Anise vinegar. Convert into a coarse powder anise seed 5 
parts, caraway seed , fennel and coriander seed each J, pour 5 
parts of alcohol and 45 parts of strong vinegar over the powders, 
close the vessel air-tight and let the whole digest in a warm place 
for 6 to 8 days, shaking frequently. Then strain the liquid off, 
press out the residue, filter the vinegar, and put it up in bottles. 

Anchovy vinegar. Reduce 1 pound of boned anchovies to a 
pulp in a mortar and pass the mass through a hair-sieve. The 
bones and parts which do not pass through the sieve are boiled 
for 15 minutes in a pint of water and strained. To the strained 
liquor add 2J ounces of salt and the same quantity of flour 
together with the pulped anchovies, and allow the whole to sim- 
mer for 3 or 4 minutes ; as soon as the mixture is cold add J pint 
of strong vinegar. 

Tarragon vinegar. Pick the young tender leaves of dragon's- 
wort (Artemisia dracunculus) when the first flower-buds appear. 
Bruise the leaves, place them in a suitable vessel, pour good wine- 
vinegar over them, and let the whole stand for a few days. Then 
strain the vinegar through a cloth, filter and bottle. The bottles 
must be filled entirely full, as otherwise the vinegar will not keep. 

Compound tarragon vinegar. Comminute leaves of dragon's- 
wort 100 parts, common bean leaves 25, leaves of basil and mar- 
joram each 12J, bay leaves and orris root each 25, cloves 3J, cinna- 
mon 6J, and shallots 25. Put all in a suitable vessel, pour 700 
to 750 parts of pure, strong vinegar over it, let it stand in a warm 
place and digest 5 or 6 days, frequently agitating it. Then strain 
the vinegar through linen, press out the residue, add 25 parts of 
alcohol, and filter. Keep the vinegar in well-corked bottles in 
a cool, dark place. 

Effervescing vinegar. Dissolve 500 parts of loaf sugar in 5000 
parts of water, add lemon juice and rind cut up in the proportion 
of 1 lemon to 1 lb. of sugar, 1J parts of the best cinnamon, and 
12 parts of beer yeast thoroughly washed. Place the whole in a 
barrel, and after agitating it thoroughly let it ferment at a tem- 
perature of 55 to 60 F. When fermentation has ceased the 
vinous fluid is strained and mixed with 1000 parts of best wine- 



PREPARATION OF VINEGAR SPECIALTIES. 173 

vinegar, previously boiled up, and yeast in the proportion of 1 
spoonful to 5 Ibs. of sugar. The fluid is then distributed in sev- 
eral earthenware pots and exposed to a temperature of 77 to 
88 F. until it has been converted into strong vinegar. This, 
while remaining in the pots, is mixed with 200 parts of French 
brandy and after two days bottled in small bottles. To each 
pound of this vinegar are added 4 part of crystallized tartaric 
acid, pulverized, and J part of bicarbonate of soda. The bottles, 
as soon as the respective portion of the mixture has been added 
to each, must be corked as quickly as possible and then stored 
in a cool place. 

Herb vinegar. Chop fine the leaves of marjoram and thyme 
each 13J parts, common bean leaves 6J, leaves of mint, basil, and 
celery each 3J, and fresh shallots 1J. Pour 600 or 700 parts of 
good vinegar over the herbs and treat in the same manner as given 
for compound tarragon vinegar. 

Pine-apple vinegar. This excellent vinegar soon loses its 
flavor, and it is therefore best to prepare a small quantity at 
a time and keep in bottles closed air-tight. 

Bruise the slices of pine-apple and pour over them a consider- 
able quantity of vinegar. Close the vessel air-tight and let it 
stand 12 hours ; then pour off the vinegar and filter. 

Celery vinegar. Celery seed 4J ozs., vinegar 1 pint. Digest 
14 days; filter. 

Clove vinegar. Cloves 3J ozs., vinegar 1 pint. Digest 7 days 
and strain. 

Mustard vinegar. Black mustard seeds 2 ozs., vinegar 1 pint. 
Digest one week and filter. 

Lovage vinegar. Lovage root 2 ozs., lovage seed 1 oz., vinegar 
10 ozs. Digest one week and filter. 

Preparation of Acetic Ether. 

Among the numerous combinations into which acetic acid 
enters with other bodies, acetic ether is of special value for the 
vinegar manufacturer, it being directly used in the fabrication of 
vinegar. It is readily formed on alcohol coming in contact with 
acetic acid, and it would seem with special ease when the latter 



174 VIXKOAII, niJEii, AND FRUIT-WINKS. 

in in a nawynt fcitc. Hence a *rnall quantity of it i found in 
nearly all red wine* not prepared by fermentation in closed vat*, 
it* presence being din? to the formation of a small quantity of 
o/ictie acid from the alcohol, which immediately combines with 
the ethyl oxide or ether. 

In vinegar containing a small quantity of unchanged alcohol 
Home acetic either formal by the conversion of this alcohol into 
acetic acid is alwayH present, and imparting a very delicate and 
agreeable tjoiiqiict to the vinegar, it i- recommended to conduct 
the fabrication of a fine article so that it contains a small quan- 
tity of it. 

It IH, however, not absolutely necessary to leave a small quan- 
tity of alcohol in the vinegar, as either acetic c-ther or alcohol 
can U; directly added to the finished product. But in both casen 
the vinegar haw to be Htored for neveral weeks; in the first, 'for 
the purpose of harnioni/inc the* cxlors of acetic ether and of acetic 
acid, and in the latter, for the? formation of acetic ether. 

A fluid quite rich in awtie ctlrcr and very suitable for impart- 
ing bouquet to table vinegar can in a very simple manner be 
prepnred by mixing in a flask one volume of highly concentrated 
acetic acid with two volumes of 95 or !KJ per cent, alcohol, and after 
cloning flic flask air-tight, allowing the fluid to stand in a warm 
room for several months. The resulting fluid is us(*l as an addi- 
tion to the vinegar whose odor is to be improved. Entirely pure 
acetic ether is best prepared in the following mariner: To 9 parts 
of concentrated sulphuric acid .*5.(J parts of commercial absolute 
alcohol are added by means of a funnel tube which reaches to the 
bottom of the vessel, at the same time keeping the liquid well 
stirred. After standing for 24 hours this mixture is added to o* 
parts of sodium acetate which has previously been fused and 
broken into small fragments, and after 12 hours the mixture is 
distilled, Thus (> parts of pure acetic ether are obtained, from 
which, by rectifying over calcium chloride, all traces of water arc 
removed. 

Pure acetic ether or ethyl acetate has the composition ,?\ , 8 M 

^ y 2*V ' .) 

and represents a fluid clear as water with an agreeable but stupe- 
fying odor. Its specific gravity is ().!).'J2 and it boils at 105.2 F. 



FABRICATION OF WINE-VINEGAR. 175 

On account of its volatility it has to be kept in well-stoppered 
bottles, best in a cool place. 

About 3J to 7 ozs. of acetic ether suffice for the improvement 
of the odor of 100 quarts of vinegar. 



CHAPTER XVIII. 

FABRICATION OF WINE-VINEGAR. 

WINE being an alcoholic liquid with a content of alcohol vary- 
ing between 6 and 14 per cent, evidently furnishes an excellent 
material for the fabrication of vinegar. However, only in rare 
cases wine still palatable is used, the chief supply for this pur- 
pose being derived from wine, especially wines with from 8 to 9 
per cent, of alcohol, which have deteriorated on account of incor- 
rect treatment in the cellar and consequently have become unsal- 
able as a beverage. Stronger wines are less difficult to keep in 
the cellar, and in case they should spoil and become unfit for a 
beverage can be more profitably utilized in the fabrication of 
cognac. 

Wine-vinegar differs from the ordinary varieties not only in 
containing, besides peculiar extractive substances, tartaric acid, 
tartrates, etc., but also in possessing a very agreeable odor due to 
the change of the odoriferous substances contained in the wine. 

In wine-growing countries large sums are annually lost on ac- 
count of spoiled wine, the latter being generally sold at a very 
low price to vinegar factories, where it is worked as alcoholic 
liquid either by itself or in connection with other materials. On 
account of the process used the quality of the resulting product 
is not what it should be, the wine being worked into vinegar 
either in quick -process generators or by a method to be described 
later on, to which the term " vinegar boiling" may be applied. 
Vinegar, to be sure, is obtained in both cases, but the product is 
not especially fine, because wine-vinegar of an excellent quality 
can only be prepared by not allowing the process of oxidation to 



176 VINEGAR, CIDER, AND FRUIT-WINES. 

proceed too rapidly and preventing the appearance of other fer- 
menting processes besides that of acetous fermentation. 

Every vinegar, no matter from what kind of raw material it 
may have been prepared, acquires a finer odor by storing ; and 
this is especially the case with wine-vinegar, which, when freshly 
made, has not an agreeable, but rather an unpleasant and stupe- 
fying, odor. By storing such vinegar in an apartment in which 
the ordinary temperature of a living room prevails, it acquires in 
the course of a few weeks an agreeable bouquet, which, similar to 
that of wine, increases in fineness for a certain time, and can be 
preserved unchanged for a long time by excluding the air and 
storing in a cool room ; finally, however, it decreases. 

Drinkable wine can be profitably used for the manufacture of 
vinegar only in countries where, in consequence of a very abun- 
dant harvest, it can be bought at astonishingly low prices, as for 
instance in Hungary, where a hectoliter (22 imp. gallons) of ordi- 
nary wine can in some seasons be bought for a few dollars. 
Otherwise only spoiled or " sick" wines, which are cheap enough, 
are used for the purpose. 

The term " sick" is generally applied to wines in which altera- 
tions take place by the activity of a certain ferment, which when 
progressed to a certain degree renders the wine unfit for a beve- 
rage. "Turning sour" is, for instance, a sickness frequently 
occurring in wines poor in alcohol ; it manifests itself by the 
development of large masses of a certain ferment which quickly 
destroys the tartaric acid contained in the wine. Another sickness 
chiefly occurring in red wines is the so-called "turning bitter," 
the wine, as the term implies, acquiring in a short time by the 
action of a peculiar ferment such a disagreeable bitter taste as to 
render it absolutely unfit for drinking. Such wine cannot be 
used even for vinegar, the latter showing the same disagreeable 
bitter taste. Wine attacked by what is called "lactic acid de- 
generation" can be used for the manufacture of vinegar, but 
yields a" product of very inferior quality, because on the wine 
being subjected to acetous fermentation the lactic acid contained 
in it is readily converted into butyric acid, which possesses a dis- 
agreeable rancid odor completely killing the pleasant aroma of 
the bouquet substances. There only remains as a material 



FABRICATION OF WIXE-VIXEGAR. 177 

actually fit for the preparation of wine-vinegar, wine attacked by 
" acetous degeneration ," i. e., wine already so much changed by 
the vinegar ferment as to render it unfit for a beverage, and, 
further, wine which though not sick is unsound, showing a taste 
of mold, of the barrel, etc. 

Wine no longer young and not overly rich in alcohol is espe- 
cially adapted for the nourishment of the vinegar ferment. Such 
wine need only be exposed to a somewhat higher temperature in 
order to induce acetous fermentation, which, if not disturbed in its 
progress, will finally convert all the alcohol in the wine to acetic 
acid. 

It may here be remarked that every normal wine always con- 
tains, besides the bodies belonging to the series of fatty acids, 
acetic acid, though only about a few ten-thousandths of its weight. 
By storing the wine, the acetic acid does not increase, but becomes 
rather less, it being consumed in the formation of compound 
ethers. Hence, a rapid increase of the acetic acid is an indica- 
tion of the wine being attacked by acetous degeneration, and if 
examined with the microscope the ferment characteristic of 
acetous fermentation will be found upon its surface. Many 
remedies have been proposed for the cure of acetous degenera- 
tion, but none of them is of any value except heating the wine to 
about 140 F., whereby the vinegar ferment is killed and the 
further progress of acetous fermentation checked. There is, 
however, absolutely no remedy for the removal or neutralization 
of the acetic acid already present in the wine. Heating the wine 
can only be recommended when the evil has been in existence 
but a short time and the increase of acetic acid can be de- 
tected only by a very sensitive tongue. Mixing wine attacked by 
acetous degeneration with sound wine in order to cover up the 
acid taste is especially unadvisable ; nothing can be attained by 
it except a short delay in the reappearance of the evil and the 
transmission of the infection to the sound wine. There are but 
two ways in which wine attacked by acetous degeneration can be 
in anywise profitably utilized : by employing it for the preparation 
of cognac or converting it into wine- vinegar. For the first a dis- 
tilling apparatus is required, and, consequently, cannot be effected 
12 



178 VINEGAR, CIDER, AND FRUIT-WINES. 

by every wine-grower, while for the latter nothing is necessary 
but a few vessels readily procured. 

Young white wine if attacked by acetous degeneration is also 
fit for nothing else than the preparation of vinegar. On account 
of its large content of albuminous substances it is, however, more 
suitable for the nourishment of the mold ferment than for that of 
the vinegar ferment, and consequently many difficulties occur in 
its conversion into vinegar. These difficulties can, however, be 
prevented by mixing such wine with much air and storing it for 
some time in barrels filled up to the bung, or heating it after 
mixing with air to about 140 F., the separation of the albumi- 
nous substances being effected by both means, though more 
rapidly by the latter. Before being further worked the wine has 
to be filtered to remove the now insoluble albuminous substances, 
whose presence might otherwise give rise to other injurious com- 
plications. 

Before the appearance of the phylloxera in France and the 
consequent decrease in the production of very ordinary wines and a . 
better chance of disposing of slightly sick wines doctored by heat- 
ing, the manufacture of wine vinegar was extensively carried on in 
many communities, the sale of this product realizing very large 
sums. A number of commercial travellers regularly visited the 
wine-growing districts simply for the purpose of buying up sick 
wines to be worked into vinegar by the factories represented by 
them. And, notwithstanding the process of manufacture in general 
use was rather incomplete, it furnished a highly valued article, 
though only with a considerable loss of substance. Pasteur made 
some experiments regarding the mode of manufacture and recom- 
mended very valuable improvements. 

The question, what constitutes the superiority of wine vinegar 
over the ordinary product obtained from alcohol, is not difficult 
for those who have an accurate knowledge of the constitution 
of wine to answer. Wine, besides the ordinary alcohol (ethyl 
alcohol), contains very small quantities of other alcohols, for in- 
stance, amyl alcohol, which, in the same manner as ethyl alcohol 
is converted into acetic acid, are changed into acids possessing a 
peculiar odor. Moreover, wine very likely contains a series of 
odoriferous substances which together produce the peculiar aroma 



FABRICATION OF WIXE-VIXEGAR. 170 

termed bouquet or flower, the cenanthic ether found in every wine 
forming so to say the keynote in the harmony of the odoriferous 
substances constituting the bouquet. In the conversion of wine 
into vinegar these bouquet substances are also changed in such a 
manner that bodies distinguished by a characteristic odor are 
formed. Furthermore, wine contains glycerin, a series of non- 
volatile organic acids ; tartaric, malic, succinic acids etc., and 
finally the so-called extractive substances. What change these 
bodies undergo is not accurately known, but all of them are very 
likely subject to certain modifications because a smaller quantity 
of extractive substances and of non-volatile acids is found in the 
vinegar than in the original wine. The following table shows the 
composition of wine and of the vinegar formed from it : 

Wine contains Wine-vinegar contains 

Water, Water, 

Ethyl alcohol, Ethyl alcohol (none or very little), 

Other alcohols, Other alcohols (changed), 

Glycerin, Glycerin (less ?), 

Acetic acid (traces), Acetic acid (much newly formed), 

Tartaric acid, Tartaric acid (less). 

Tartar, Tartar (less), 

Malic acid, Malic acid (less), 

Succinic acid, Succinic acid (less), 

Tannin, Tannin (changed), [changed), 

(Enanthic ether, CEnanthic ether (changed and un- 

Bouquet substances, Bouquet substances 

Extractive substances, Extractive " > changed, 

Coloring substances. Coloring " 

Acetic ether and other) newly 
compound ethers / formed. 

The above comparison shows the thorough modification wine 
undergoes in being converted into vinegar, and that the resulting 
product must have a bouquet or flower having a certain connec- 
tion with that of the wine. 

Before entering upon a description of the various methods of 
fabricating wine-vinegar it may be mentioned that an actually 
fine product can only be obtained by a slow process of acetifica- 
tion, numerous experiments having shown that wine treated by 
the quick process yields a product very poor in bouquet. 



180 VINEGAR, CIDER, AND FRUIT-WIXES. 

Boiling of Wine- Vinegar. 

The oldest method for the preparation of wine-vinegar is that 
to which the term " boiling of wine-vinegar' 7 (Weinessig-Siederei) 
has been applied. A barrel was filled f full with wine to be 
converted into vinegar ; a portion of the fluid was then heated 
to boiling and poured back into the barrel. Upon the wine thus 
heated to about 86 F. the development of the vinegar ferment 
commenced, and in the course of a few months the greater portion 
of the alcohol was converted into acetic acid. The greater portion 
of the contents of the barrel was then drawn off as " ripe wine- 
vinegar/' the barrel again filled J full with wine, and a portion of 
this heated ; the operation was continued in this manner until so 
much slimy sediment had accumulated in the barrel as to render 
its complete emptying and cleansing necessary. This crude 'pro- 
cess, which, as mentioned, was known in Germany as " vinegar 
boiling/' was similar to the method formerly in general use in 
France, and which, being still partially practised there in some 
large wine-vinegar factories, for instance in Orleans, may be 
designated as the 

Old French Method of Manufacturing Wine-Vinegar. 

The casks, called mothers, which are employed hold not more 
than 22 gallons, each cask being filled i full. Immediately 
above the level of the fluid a hole is bored in the surface of 
the front end of each cask, this hole as well as the bung-hole re- 
maining open ; a stop-cock for the discharge of the fluid is placed 
in the lower part of the cask. The casks are placed in rows in 
the open air, eight, ten, fifteen, or twenty such rows constituting 
what is termed a vinegar field '. This so-called fielding, which is 
carried on from spring to fall, may be suitable for the southern 
part of France, but cannot be recommended for more northern 
regions, as the temperature may fall very low during the night 
and rise very high during the day. Experience has shown that 
the augmentation and efficacy of the ferments are very much in- 
jured by strong variations of temperature, and consequently it is 
decidedly preferable to keep the casks in a room the temperature 



FABRICATION OF WINE-VINEGAR. . 181 

of which can be maintained at least at 68 F. The wine re- 
mains in these casks until it is converted into vinegar ; the latter 
is then drawn off by means of the above-mentioned stop-cock 
and the casks are again filled with wine, etc. The hole in the 
front end of the cask and the bung-hole permit the free access 
of air to the surface of the wine. In other French factories the 
work is carried on according to a method somewhat different 
from the one just described. Casks having a capacity of up to 
100 gallons are used, each cask having in the surface of the front 
end a square aperture, which serves to charge the casks with 
wine as well as for the influx of air. The casks are placed in three 
rows one above another in a room which can be heated. In the 
beginning of the operation a certain quantity of strong vinegar 
is brought into the casks; about one-fourth of its volume of 
wine is then added, and at intervals of eight days about 10 
quarts more. When the cask is nearly filled up to the above- 
mentioned aperture, the regular process of drawing off vinegar 
and filling up again with wine is commenced. If, for instance, 
10 quarts of finished vinegar are drawn off, the same quantity of 
wine is replaced in the cask, and suppose that, according to the 
manner of working, 7, 8, or 10 days are required for the con- 
version of this quantity into vinegar, 10 quarts of vinegar are 
again drawn off after the expiration of that time, this being con- 
tinued until a disturbance occurs. 

In the course of time large masses of slimy matter, consisting of 
albuminous substances which have become insoluble, coloring 
substances, vinegar ferment vegetating below the surface (the so- 
called mother of vinegar), decayed vinegar ferment, etc., form a 
deposit in the cask, and finally accumulate to such an extent as 
to occupy half the volume of the cask, so that the latter has to 
be. emptied and thoroughly cleansed. Sometimes the operation 
has to be interrupted much sooner on account of the contents of 
the cask acquiring a disagreeable, putrid odor. This appearance 
of putrefaction is generally due to vinegar eels settling in the in- 
terior of the cask as a rule, immediately above the level of the 
fluid and developing to such an extent that they form a slimy 
coating on the barrel and upon the fluid and suppress the devel- 
opment of the vinegar ferment. These animalcules are destroyed 



182 VINEGAR, CIDER, AND FRUIT- WINES. 

by being deprived of air, and, hence, when the vinegar ferment 
is brought to vigorous development it withdraws so much of the 
oxygen from the air in the cask that many of them die and their 
bodies sink to the bottom, where they sooner or later putrefy. If 
this putrefying process takes place before a cleansing of the casks 
is considered necessary, it progresses to such an extent that the 
entire contents of the cask are converted into a stinking mass 
which has to be removed as quickly as possible. The casks in 
which such disturbances take place must of course be carefully 
cleansed by sulphuring and washing with boiling water before 
they are again used. 

Modern French Method of Preparing Wine- Vinegar. . 

The description of the older French methods given aboye 
shows that they are very crude ; their improvement is, however, 
not difficult, the principal being to place the casks in a room sub- 
ject to but slight variations of temperature, which can be best 
effected by providing a good self-regulating stove. The temper- 
ature near the ceiling being higher than that immediately above 
the floor, the formation of vinegar will take place more rapidly 
in the casks placed in the uppermost tier than in those in the 
lowest, and consequently the wine in them will in a shorter time 
be converted into vinegar. 

The first thing in starting the operation according to the old 
French method is to acidulate the casks by pouring 10 to 20 
quarts of boiling hot vinegar into each and then adding 10 to 
15 quarts of wine; after some time, when the wine is acidulated, 
the cask is filled up to the previously mentioned aperture and 
left to itself until the contents are sufficiently acetified, when a 
portion of the vinegar is "drawn off and replaced by wine, this 
drawing off of vinegar and refilling with wine being continued 
until the cask on account of the accumulation of sediment has to 
be cleansed. 

This method, which is sometimes very minutely described in 
books, could only develop at a time when nothing was known of 
the chemico-physiological process of the formation of vinegar or 
only erroneous opinions in regard to it prevailed. It is full of 



FABRICATION OF WINE- VINEGAR. 183 

defects from beginning to end. The acidulation of the casks with 
boiling vinegar is simply preposterous, because by heating the 
vinegar and pouring it boiling hot into the cask not only the 
vinegar ferment contained in it is destroyed but also that present 
in the cask or wine itself. That acetous fermentation takes place 
notwithstanding is very likely due to the following causes : 

The hot fluid in the cask gradually cools off and is finally re- 
duced to the degree of temperature most favorable to the develop- 
ment of the vinegar ferment ; in the same proportion as cooling 
off takes place the air contracts in the cask and air enters from 
the outside. The latter, however, carries with it germs of vinegar 
ferment which rapidly develop upon the fluid when reduced to the 
proper temperature and cause its acetification. The air pene- 
trating into the cask may, however, accidentally contain no vine- 
gar ferment, or that contained in it may not reach the wine ; in 
such case the wine may for weeks remain in the cask without any 
perceptible acetification taking place until the latter finally ap- 
pears by an accidental development of the vinegar ferment. This 
uncertainty can, however, be readily avoided by the direct culti- 
vation of the vinegar ferment- upon the wine to be acetified. 
Milk, as is well known, turns sour on exposure to the air by the 
milk sugar being converted into lactic acid by the action of a 
ferment frequently occurring in the air, this souring taking place 
in several hours or several days according to the temperature to 
which the milk is exposed. It is further a well-known fact that the 
addition of a few drops of sour to sweet milk suflices to imme- 
diately induce the formation of lactic acid in the latter ; the fer- 
ment of lactic acid fermentation being in the true sense of the word 
sowed upon the milk. The ferment develops very rapidly, con- 
verts the sugar into lactic acid, and in a short time turns the en- 
tire quantity of milk sour. 

Exactly the same course may be pursued as regards the vinegar 
ferment, it being only necessary to mix the wine with a fluid 
containing living vinegar ferment and place it in a sufficiently 
warm room in order to immediately start the process of the 
formation of acetic acid ; in this case the vinegar ferment is 
sowed upon the wine, or, in other words, the wine is infected with 
vinegar ferment and intentionally made " sick." This method of 



184 VINEGAR, CIDER, AND FRUIT-WIXES. 

transmitting ferment to the fluid to be fermented has for a long 
time been in use in the fabrication of beer and of alcohol. In the 
brewery the wort, and, in the distillery, the mash, is brought into 
fermentation by " setting" it with yeast, L e., alcohol ferment is 
intentionally added. The "setting of wine" with vinegar fer- 
ment is the only correct method for the preparation of vinegar 
from wine. 

Before entering upon a description of this process it will be 
necessary to discuss a few undesirable phenomena which may ap- 
pear in the conversion of wine into vinegar. A thick white skin 
having the appearance of a ruffle may frequently form upon the 
surface of the wine set for acetification, the wine in this case becom- 
ing constantly poorer in alcohol, but not sour. Sometimes the pre- 
viously steady increase in the content of acid in the wine to be aceti- 
fied suddenly ceases and a very rapid decrease in the content of aeid 
takes place, the development of the white skin upon the surface 
being also in this case observed. 

The formation of this white coating upon the surface is due to 
the development of mold ferment whose cells in a short time 
augment to such an extent as to form a thick membranous layer, 
the folds being formed by the superposition of the cells. The 
mold ferment has the property of converting alcohol as well as 
acetic acid into carbonic acid and water, and consequently if it 
settles upon wine the latter becomes poorer in alcohol, and if upon 
wine containing already a certain quantity of acetic acid the 
latter is also decomposed. The mold ferment requires, however, 
considerable quantities of nitrogenous combinations for its vigor- 
ous development, and, therefore, readily settles upon young wine 
which contains a large quantity of albuminous bodies in solution. 
This fact explains the reason why young wine is seldom attacked 
by acetous generation, but it readily becomes moldy, and, conse- 
quently, cannot be recommended as material for the fabrication of 
vinegar except the albuminous substances be first separated by 
heating the wine to 140 F., which is best effected by means of 
the apparatus shown in Fig. 39, p. 149. 

Another serious annoyance in the fabrication of wine-vinegar 
is the appearance of vinegar eels, which, if not checked in time, 
may lead to the interruption of the entire process. These ani- 



FABRICATION OF WINE-VIXEGAR. 185 

malcules are but seldom found in factories working with pump or 
well water, but frequently in those using river water, and conse- 
quently their introduction is likely due to such water. In case 
of their appearance in large masses it is best to interrupt the 
process in time in order to prevent the previously mentioned 
phenomena of putrefaction. The fluid containing the vinegar- 
eels should be drawn oif into a thoroughly sulphured barrel. The 
sulphurous acid kills the vinegar eels as well as the vinegar fer- 
ment, and the filtered fluid, after standing a few weeks, whereby 
the sulphurous acid is converted into sulphuric acid, can again 
be used as alcoholic liquid. The vessels in which the vinegar 
eels have settled must also be thoroughly sulphured and then 
repeatedly washed with water before being re-used for the fabri- 
cation of vinegar. 

In the apartment containing the vessels used for the fabrication 
of wine-vinegar the greatest cleanliness should prevail ; in fact 
one cannot be too scrupulous in this respect, as otherwise by- 
fermentations readily take place, and another plague, the vinegar- 
lice, or more correctly vinegar-mites (see p. 137), may appear. 
Should any of these evils happen the apartment, fluids, and ves- 
sels must be thoroughly disinfected by means of sulphurous acid. 

Method of the Fabrication of Wine-Vinegar according to Berscli. 

As previously mentioned, the fabrication of wine-vinegar by 
the quick process cannot be recommended, the odoriferous sub- 
stances which give the product its special value being almost 
entirely lost thereby ; but neither can it be recommended to 
WT>rk according to one of the French processes previously de- 
scribed, as they require too much time, are accompanied by large 
losses as regards yield, and render it difficult to maintain the 
necessary cleanliness during the operation. All these evils can 
be avoided by following the method first proposed, in 1876, by 
Dr. Josef Bersch, and for some time practised on a manufac- 
turing scale. 

The essential part of the entire process is the infection of the 
wine in suitable vessels with artificially cultivated vinegar fer- 
ment under conditions in which the latter can rapidly augment. 



186 VINEGAR, CIDER, AND FRUIT- WINES. 

The vessels are so arranged that the finished vinegar can be re- 
moved and replaced by wine to be acetified without disturbing 
the ferment, one being thus enabled to uninterruptedly continue 
the process of the formation of vinegar for a long time, and pro- 
ducing vinegar unsurpassed by any other product as regards deli- 
cacy of taste and odor. According to the above statement, the 
operation includes the cultivation of the vinegar ferment on a small 
scale and on a large scale, the former for the production of- pure 
ferment and the latter for obtaining wine-vinegar. 

The cultivation of pure vinegar ferment on a small scale is 
best effected by heating wine in a porcelain or glass dish to 140 
or 150 F., then mixing it with an equal volume of vinegar and 
pouring the resulting fluid into shallow porcelain plates, which 
are placed in a warm room. In a short time, generally in 24 to 
30 hours, the veil-like layer of vinegar ferment previously de- 
scribed is observed upon the surface of the fluid. If, besides the 
dull spots which are characteristic of pure vinegar ferment, spots 
of a pure white color are formed, it is an indication of the devel- 
opment of mold ferment. The contents of the plates showing 
this phenomenon have to be boiled and then again exposed to 
the air. 

The wine to be acetified is in large, shallow vats, and is 
brought to fermentation by carefully submerging in it one of 
the above-mentioned plates containing pure vinegar ferment, so 
that the latter is distributed upon the surface; the plate is then 
withdrawn. The ferment augments very rapidly, so that, in 24 
hours, the surface of the wine in the vat is entirely covered with 
a thin veil of it. By keeping the temperature of the room in 
which the vats are placed at about 68 F., the acetification of 
the wine proceeds rapidly, tests repeated at intervals of 24 hours 
showing a constant increase in the content of acid, until in about 
8 days all the wine is converted into vinegar and is drawn off. 
To avoid the necessity of especially infecting the next quantity 
of wine the finished vinegar is not entirely drawn off, a small 
quantity (about J to 1 inch deep) upon the surface of which the 
vinegar ferment floats being allowed to remain in the vat. By 
now introducing a fresh lot of wine the vinegar ferment propa- 
gates upon it and after some time converts it into vinegar. 



FABRICATION OF WINE- VINEGAR. 187 

With sufficient care the process of the formation of vinegar 
could thus be uninterruptedly carried on for any length of time 
by transferring the vinegar ferment from the finished vinegar to 
the wine, if a cleansing of the vat were not from time to time re- 
quired, on account of the accumulation on the bottom of the 
vessel of decayed vinegar ferment and flakes of albumen which 
have become insoluble. When the vat is to be cleansed the last 
batch of vinegar is drawn off as long as it runs off clear, and the 
turbid remainder in the bottom of the vat collected in a special 
cask, where it is allowed to repose until clear. The vat is then 
thoroughly cleansed with water, and after filling it again with 
wine, the latter is mixed with pure vinegar ferment in the manner 
already described. 

If, as may happen in very rare cases, mold ferment in the form 
of the above-mentioned white spots appears upon the surface be- 
sides vinegar ferment, the vat must be at once emptied. The 
process should also be interrupted in case of the development of 
the so-called mother of vinegar. The latter appears generally in 
the form of a soft mass of the consistency of jelly submerged in 
the fluid, and consists of vinegar ferment, which, however, does 
not, on account of not being in direct contact with the air, pro- 
duce acetic acid. The fluid to be acetified can be readily separated 
from the mother of vinegar by filtering through a close cloth ; 
the mother of vinegar remaining upon the latter and finally drying 
to a whitish mass resembling very thin tissue paper. 

From the above it will be seen that the rational preparation of 
wine-vinegar is a very simple matter ; but there are some diffi- 
culties which can, however, be entirely prevented or readily re- 
moved. The vinegar ferment is very sensitive towards sudden 
changes in the composition of the fluid upon which it lives, as 
well as towards quick changes in the temperature. The sudden 
change in the composition of the fluid is prevented by not draw- 
ing off all the finished vinegar, but allowing a small portion to 
remain in the vat. The fresh supply of wine entering from be- 
low then lifts up the remainder of vinegar, together with the fer- 
ment floating upon it, and the mixture of both fluids is effected 
so gradually that the change in the composition of the nourishing 



188 VINEGAR, CIDER, AND FRUIT-WINES. 

fluid proceeds very slowly. A sudden change in the temperature 
of the workroom can, of course, be readily prevented by proper 
heating. 

Execution of the Preceding Process on a Manufacturing Scale. 

The manufacturer of wine-vinegar has but little choice in the 
selection of his material ; he must take the spoiled wines as they 
come. The only difference as regards the value of the material 
is in the content of alcohol ; the greater the latter, the more 
valuable the material. Wines with a content of alcohol not 
much above 6 per cent, are best used as they are, as they yield 
vinegar with about 5J per cent, of acetic acid. It is advisable, 
however, to dilute stronger wines with a content of alcohol up to 
10 per cent., so that they contain not more than about 6 per cent. 
For the dilution of such wine either water or ordinary vinegar 
can be used. The strength of the latter must be so chosen that 
the wine-vinegar prepared from a mixture of wine and vinegar 
contains 5J to 6 per cent, of acetic acid. The proportions in 
which vinegar and wine are to be mixed for this purpose are 
found by a simple calculation after accurately determining the 
content of alcohol in the wine and that of acetic acid in the 
vinegar. 

The workroom should be so situated as to be protected against 
sudden changes in the temperature and provided with a furnace 
or self-regulating stove. The vessels for the formation of 
vinegar are placed upon suitable supports, and a table for holding 
the plates for the cultivation of the vinegar ferment should be 
provided. If the size of the room permit, it is advisable to store 
in it a few barrels of the material to be worked, the fluid thereby 
gradually acquiring the proper temperature. 

For the formation of the vinegar very shallow vats, best with a 
diameter of 3J to 5 feet and a depth of 9 to 14 inches, are used. 

The' iron hoops are protected from the action of the acetic 
vapors by a coat of asphalt lacquer. The vats are placed in the 
position they are to occupy in the workroom and filled with 
water up to about If to 3} inches from the top, the height of the 
level of the fluid being marked on the inside wall. At distances 



FABRICATION OF WINE-VINEGAR. 189 

of 3f inches apart, and 5f inches in larger vats, holes, I, Fig. 42, 
of 0.39 inch diameter are then bored in the wall of the vat ; one 
hole is, however, bored in a place about 0.39 inch deeper than /, 
and in this hole is fitted a glass tube, g, bent at a right angle, 

Fig. 42. 




Vat for the Preparation of Wine- Vinegar. 

under which is placed an ordinary tumbler. In the bottom of 
the vat is a tap-hole, Z, closed by a stopper. 

If the vat be filled during the operation with wine, the latter 
can only rise until it begins to run off at g. The level of the fluid 
being but little below the holes /, an uninterrupted change in the 
layer of air above the fluid takes place. A wooden spigot, H, is 
fitted in the vat about f to 1 inch above the bottom. In the 
centre of the lid D, which lies loosely upon the vat, is an aper- 
ture, 0; in a second aperture a thermometer, T, is inserted, 
whose bulb dips into the fluid ; and in a third aperture is fitted a 
glass funnel, R, reaching nearly to the bottom of the vat. 

The operation in such a factory commences with the cultivation 
of the vinegar ferment. For this purpose as many shallow por- 
celain plates as there are vats are placed upon the table and wine 
to the depth of | to j inch poured in each ; the room should be 
heated and kept at a temperature of 86 F. The manner of the 
development of the vinegar ferment upon the fluid in the plates 
as well as the precautions which have to be taken has already 
been described. In the commencement of the fabrication the 
cultivation of the ferment requires great attention, it being fre- 
quently disturbed by the development of mold ferment, but 
when the factory is once in a proper state of working it is readily 
effected because the air of the workroom - then contains a large 



190 VINEGAR, CIDER, AND FRUIT-WINES. 

quantity of the ferment, which rapidly augments on coming in 
contact with a fluid favorable for its development. 

The vats are charged by allowing the fluid to be converted into 
vinegar to flow in until it begins to run out through g. The 
setting with ferment is then effected by carefully emptying the 
contents of one of the plates upon the surface of the fluid, so that 
the greater portion remains floating upon it. Finally the lid is 
placed upon the vat and the latter left to itself. 

The ferment soon covers the entire surface of the fluid in the 
vat, and the commencement of the process of oxidation is in a 
short time recognized by the rise of the thermometer dipping into 
the fluid. As long as the quantity of alcohol in the fluid is com- 
paratively large the process of the formation of acetic acid and 
the augmentation of the ferment take place very rapidly and the 
thermometer rises constantly ; but with an increase in the quan- 
tity of acetic acid these processes become slower, which is indi- 
cated by a fall in the temperature of the fluid. The energy of 
the process must, however, not be allowed to sink below a certain 
limit, care being had to keep it up by raising the temperature of 
the workroom, but not higher than is absolutely necessary for the 
correct working, as otherwise there would be a loss of acetic acid 
or alcohol by evaporation. 

The most convenient and business-like manner of operating a 
factory arranged as above described is to simultaneously charge 
all the vats with alcoholic liquid, it being then entirely in one's 
power to regulate the heating of the workroom according to the 
indications of the thermometer dipping into the fluid. If, for 
instance, the operation commences at 77 F., the thermometer 
will soon be observed to rise even if the temperature of the work- 
room remains unchanged. By the oxidation of the alcohol suffi- 
cient heat is liberated to increase the temperature of the fluid to 
above 95 F. ; it is, however, advisable not to allow it to rise 
above 86 or 90 F., as otherwise the losses by evaporation are 
too great. Hence, if the fluid reaches this limit of temperature 
the heating of the workroom is so regulated as to prevent a fur- 
ther rise of the thermometer, and a constant temperature is 
maintained for several days until it commences to fall almost 
simultaneously in all the vats. This fall in the temperature, as 



FABRICATION OF WINE- VINEGAR. 191 

previously mentioned, is an indication of the fluid now containing 
a comparatively large amount of acetic acid and of the slow oxi- 
dation of the remaining alcohol. In order to maintain the most 
favorable conditions for the efficacy of the vinegar ferment and 
to smoothly and rapidly complete the process the workroom is 
now so heated as to show a constant temperature of 86 F. as long 
as the fluid remains in the vats. 

Side by side with the observation of the statements of the 
thermometer a chemical examination of the fluid has to be carried 
on, this examination gaining in importance the further the forma- 
tion of vinegar progresses. If the content of alcohol in the wine to 
be worked is known, the test is up to a certain stage limited to the 
determination of the acetic acid, but if the process has so far 
advanced that to judge from the content of the fluid it contains 
scarcely 1 per cent, of alcohol, the latter has also to be determined 
by means of the ebullioscope. From this moment on the course 
of the process must be very carefully controlled and interrupted 
when still 0.15 or at the utmost 0.2 per cent, of alcohol is present ; 
this small amount of unchanged alcohol exerts a favorable effect 
upon the quality of the vinegar, acetic ether being formed from it 
and a corresponding quantity of acetic acid during the time the 
vinegar has to be stored. 

The interruption of the process is best effected by separating 
the fluid from the layer of ferment floating upon it. The stop- 
cock H, Fig. 42, is opened and left open as long as fluid runs out. 
A layer of vinegar about f to 1 inch deep upon which floats the 
vinegar ferment, remains in the vat, and the stop-cock being closed 
a fresh supply of alcoholic liquid is introduced through the funnel 
R until it begins to run out through g. The process then com- 
mences anew in the manner above described. 

Theoretically unlimited quantities of wine could be converted 
into vinegar by means of such an apparatus, as the vinegar fer- 
ment which floats upon the fluid remaining in the vat, rapidly 
augments upon the fresh supply of wine and converts it into 
vinegar. In practice an occasional short interruption of the pro- 
cess is, however, necessary. During the conversion of the wine 
the greater portion of albuminous substances held in solution in 
it separates as flakes, and, further, a portion of the vinegar ferment 



192 VINEGAR, CIDER, AND FRUIT-WINES. 

sinks below the level of the fluid and assumes the form of the 
flaky masses called mother of vinegar. The result after a number 
of operations is a slimy sediment, which finally accumulates to 
such an extent that it has to be removed ; this is effected, after 
the finished vinegar is drawn off, by opening the tap-hole Z and 
removing the slimy mass by means of a broom or crutch. The 
vat is then thoroughly washed with water and can be immediately 
recharged with wine. The slimy mass is best collected in a tall 
vat and allowed to rest. In a few days it separates into two 
layers, the upper one consisting of quite clear vinegar which can 
be used for filling up storage-barrels, and the lower one of a 
thickly-fluid mass from which a certain quantity of vinegar can 
be obtained by filtration. 

The vinegar drawn off from the vats is brought into storage 
barrels which are filled up to the bung and closed air-tight. The 
volume of the vinegar decreasing by cooling, the barrels must 
from time to time be examined and kept filled up to the bung- 
hole. While stored in the barrels the vinegar almost completely 
clarifies, and by carefully siphoning off the clear portion it can be 
at once brought into commerce without further treatment. When 
a considerable quantity of slimy sediment has collected in the 
storage-barrels it is drawn off and brought into the above-men- 
tioned clarifying vat, or is clarified by filtration. 

In case of disturbances in the fabrication by the appearance of 
mold ferment or vinegar eels, the process once commenced must 
be carried through as well as possible and then the entire opera- 
tion interrupted for the purpose of thoroughly cleansing the vessels 
by washing with boiling water or steaming. Under no circum- 
stances should it be attempted to continue working with vats 
infected with mold or vinegar eels, as it would only lead to a 
considerable loss of material and the cleansing of the vessels, 
which would have to be finally done, would be more difficult. 

In conclusion it may be remarked that it is best to bottle the 
vinegar after it has become refined and bright by storing, and close 
the bottles with new corks ; by placing the bottles horizontally 
in the cellar the vinegar acquires a finer odor without injury to its 
content of acetic acid or to its taste. 

Though vinegar prepared in the above-described manner and 



FABRICATION OF WINE-VINEGAR. 193 

racked when entirely bright into bottles remains, as a rule, un- 
changed, it may happen to become turbid and form a sediment 
which is shown by the microscope to consist of organisms. This 
phenomenon is generally accompanied by a change in the odor of 
the vinegar, and the acid taste loses sharpness and shows a pecu- 
liar insipidity. From an accurate chemical examination the 
cause of this alteration must be attributed to the decomposition 
of the tartaric and malic acids in the fluid by a ferment. The 
only sure remedy for this and all other alterations is to heat the 
vinegar to 140 F. whereby all organisms are killed. For heat- 
ing larger quantities it is recommended to pass the vinegar through 
a coil of tin-pipe surrounded by boiling water and after rapidly 
cooling the hot fluid to the ordinary temperature to store it for 
some time in a barrel for the separation of the solid bodies. 
Smaller quantities can be treated by bringing the vinegar into 
glass bottles of 10 to 15 quarts 7 capacity, placing the bottles in a 
boiler filled with water and heating to the required temperature. 
A favorable result from heating can, however, only be obtained 
with vinegar which has already acquired a fine taste and odor by 
several months' storing. Freshly-prepared wine-vinegar still 
showing the previously mentioned stupefying odor, if heated, 
does not acquire the fine bouquet it otherwise would by storing. 

Preparation of Wine- Vinegar from Lees. 

The lees left from the pressing of the wine consist of the stems, 
husks, and seeds of the grapes and contain a not unimportant 
quantity of must which in many regions is sought to be obtained 
by pouring water over them and subjecting them again to pres- 
sure. The must thus obtained, though poorer in sugar and ex- 
tractive substances than that of the first pressing, yields a drinkable 
wine which is generally used for household purposes. All the 
valuable constituents are, however, not extracted even by this 
treatment, and the remainder can be profitably used for the pre- 
paration of vinegar. In countries yielding wine of ordinary 
quality it might even be advisable to entirely omit this treatment 
of the lees with water in order to obtain an inferior quality of 
.must, and use them directly for the preparation of vinegar. 
13 



194 VINEGAR, CIDER, AND FRUIT- WINES. 

If the fresh lees are thrown in a pile and allowed to ferment, 
considerable heat will be developed in the course of a few days, 
in fact so much that the mass commences to steam. When fer- 
mentation is finished, or shortly before, an agreeable odor of acetic 
ether is evolved, which is due to the commencement of the devel- 
opment of vinegar ferment upon the lees and the formation of 
acetic acid, the latter combining with a certain quantity of the 
alcohol formed by fermentation to acetic ether. (At this stage in 
the change of the lees a small quantity of acetic ether can be ob- 
tained from them by distillation.) 

The odor of acetic ether is soon overcome by that of acetic 
acid, the conversion of the newly-formed alcohol into acetic acid 
now progressing rapidly on the surface of the lees. Later on the 
sharp odor of acetic acid again decreases, the greater portion of it 
being destroyed by mold and other ferments, the development 
of which now progresses with great rapidity in the thoroughly 
heated mass of lees ; lactic acid is formed, and later on the mass 
acquires a rancid odor calling to mind that of old cheese, which 
is due to butyric acid, valeriauic acid, etc. The lees gradually 
acquire a darker color and finally putrefaction sets in. 

If only the sugar still contained in the lees is to be obtained 
and vinegar to be prepared in the most simple manner, the fol- 
lowing process may lye used : The mass of lees as it comes from 
the press is broken up and put in a pile, where it is left to itself 
until it becomes warm and acquires the odor of alcohol and acetic 
ether. The mass is then shovelled into a vat and gently pressed 
together with a shovel. For every 220 Ibs. of lees us<$, about 10 
quarts of water are now sprinkled over the mass by means of a 
watering-pot. By the entrance of air while shovelling the pile of 
lees into the vat the action of the vinegar ferment has been accele- 
rated and a considerable quantity of alcohol converted into acetic 
acid, which is indicated by the stronger vinegar odor. The 
water permeating the lees almost completely displaces the fluid 
containing the alcohol and acetic acid, the latter running oft 
through an aperture in the bottom of the vat. It is collected 
in a shallow vessel placed in an apartment having the ordinary 
temperature of a living room, and is allowed to rest. The vine- 
gar ferment present in abundance in the fluid rises to the surface, 



FABRICATION OF WIXE-YIXEGAR. 195 

where it quickly augments and converts the remainder of the 
alcohol in the fluid into acetic acid. The only difficulty to be 
overcome in preparing the vinegar according to this method is 
the appearance of the mold ferment upon the surface of the fluid. 
This can, however, be met by removing the growth of this fer- 
ment, which is recognized by its pure white color, by means of 
a spoon as soon as it has attained the thickness of a few milli- 
meters. The vinegar ferment then soon commences to augment 
and suppresses the further growth of the mold ferment. 

If the grapes originally used contained from 18 to 20 per cent, 
of sugar, the vinegar from the lees prepared according to this 
method shows, if not too much water has been used, a content of 
at least 4 or 5 per cent, of acetic acid, and consequently is imme- 
diately fit for table use. By long storing in barrels kept filled 
up to the bung-holes, it acquires a flavor resembling that of vine- 
gar prepared from wine. 

On account of the simplicity and the slight expense connected 
with it the above-described process is especially adapted for the 
preparation of vinegar for household purposes. But for commer- 
cial purposes on a large scale it is advisable to obtain a stronger 
and consequently more valuable product by a somewhat modified 
process. 

For the preparation of stronger vinegar from a fluid it is neces- 
sary to give it a higher content of alcohol or sugar. As is \vell 
known, 1 per cent, of sugar in a fluid yields after fermentation in 
round numbers 0.5 per cent, of alcohol, and the latter about 0.4 
per cent, of acetic acid. These figures, though not absolutely 
correct, are sufficiently so for practical purposes. Hence, if the 
content of acetic acid is to be increased 1 per cent., 1.2 per cent, 
of alcohol or 2.4 per cent, of sugar has to be added to every hec- 
toliter (22 imp. gallons) of the fluid to be worked into vinegar. 

The substances which impart to wine-vinegar its greater value 
as compared with ordinary vinegar are derived from the grape ; 
they are found in abundance in the must as well as in the fresh 
lees, and are yielded by the latter to water. Hence, excellent 
wine-vinegar can be prepared from the lees by working accord- 
ing to the following method : 

The lees are brought directly from the press into a vat and 



VINEGAR, CIDER, AND FRUIT-WINES. 

twice or three times a day their weight of water is poured over 
them. After standing 24 to 36 hours in not too cool a place, the 
generally strongly fermenting fluid is drawn off and what is re- 
tained by the lees gained by pressing. In this manner a fluid is 
obtained differing from the must only in a smaller content of 
sugar and tartaric acid, the so-called extractive substances con- 
tained in the must which impart to the wine its characteristic 
properties being present in abundance. 

The must obtained from the lees is now examined as to its con- 
tent of sugar. If, for instance, it shows 10 per cent, of sugar, it 
will, when fermentation is finished, have a content of nearly 5 
per cent, of alcohol and yield vinegar with about 4 per cent, of 
acetic acid. By the addition of sugar or alcohol according to the 
above-mentioned proportions a fluid can, however, be obtained 
which contains 5 or 6 or more per cent, of acetic acid. For "the 
final result of the process it is indifferent whether sugar or alcohol 
is added to the fluid, the choice depending on the current value of 
these articles. 

If sugar is used, it is dissolved directly in the fluid obtained 
from the lees and the latter allowed to ferment at about 68 
to 77 F. When working with alcohol it is advisable, in order 
to avoid loss by evaporation, to ferment the fluid from the lees 
by itself, and only add the alcohol when acetous fermentation 
is to be induced. 

During fermentation the must from the lees separates yeast 
in abundance, and being consequently turbid, is allowed to cla- 
rify in barrels kept full up to the bung. When clear, it is 
siphoned off from the sediment of yeast. 

The conversion of this wine from lees into vinegar is best 
effected by the process of Rectification, by means of ferment 
growing upon the fluid described on p. 185 et seq. The only 
difficulty which can present itself is that the wine, being young 
wine, contains a considerable quantity of albuminous substances, 
and is consequently more inclined towards the nourishment of 
mold ferment than towards that of vinegar ferment. This can, 
however, be met by setting the fluid at a higher temperature, 
about 86 F., with pure cultivated vinegar ferment, and carefully 
watching the surface for the formation of white spots of mold 



CHEMICAL EXAMINATION OF RAW MATERIALS. 197 

ferment, and immediately removing them. By proceeding in 
this manner, the entire surface will in a few hours be covered 
with vinegar ferment, when there will be no further danger of 
the dislodgment of the latter by mold ferment. 

The process of acetification being finished, the vinegar is drawn 
off into storage barrels, which must be kept full up to the bung, 
and subjected to the same treatment as the product obtained from 
wine. 



CHAPTER XIX. 

CHEMICAL EXAMINATION OF THE RAW MATERIALS AND CON- 
TROL OF THE OPERATIONS IN A VINEGAR FACTORY. 

Determination of Sugar. 

THE sacchariferous materials used by the vinegar manufacturer 
are either whiskey-mashes, malt-extracts, or must prepared from 
wine-lees, apples, etc. The determination of sugar contained in 
these fluids is effected by means of various instruments, which 
are really hydrometers, with different names and graduations. 
The instruments mostly used for the determination of sugar in 
whiskey-mashes and malt-worts are known as saccharometers, 
and directly indicate the content of sugar in the fluid in per cent: 
A similar instrument, known as the must-aerometer, serves for 
the determination of the content of sugar in grape-must. Ac- 
cording to the arrangement of their scales, the must-aerometers 
indicate either direct sugar per cent., or degrees ; in the latter 
case the use of special tables accompanying the instrument is re- 
quired for finding the per cent, of sugar corresponding to a cer- 
tain number of degrees. 

No special saccharometer for fruit-must having as yet been 
constructed, the determination of the content of sugar has to be 
effected either by a tedious method unsuitable for practice, or, 
what can be more quickly done, by fermenting a sample of the 
respective must, and after determining the quantity of alcohol, 
ascertaining from it the content of sugar. 



198 VINEGAR, CIDER, AND FRUIT-WINES. 

Iii place of special saccharometers or must -aerometers, an ordi- 
nary aerometer indicating the specific gravity can also be used, 
and the content of sugar corresponding to a certain specific grav- 
ity found from a reducing table. Tables X. to XIII. at the end 
of this volume give the content of sugar especially for wine-must, 
but also with sufficient accuracy for apple- or pear-must, accord- 
ing to the statements of the respective must-aerometers. 

Determination of Alcohol. 

In a factory using commercial spirits of wine as the fundamen- 
tal material for the fabrication of vinegar, the percentage of ab- 
solute alcohol contained in it has to be accurately determined in 
order to enable one to correctly calculate, in the manner ex- 
plained on p. 104, the quantity of water required for the prepa- 
ration of alcoholic liquid of determined strength. 

For the determination of the content of alcohol in pure spirits 
of wine consisting only of water and alcohol, instruments called 
alcoholometers are generally used ; they indicate the volumes of 
alcohol contained in 100 volumes of the spirits of wine. They 
are, however, not suited for this purpose when, as is frequently 
the case in a vinegar factory, the spirit of wine contains other 
bodies besides water and alcohol. In this case, either the alcohol 
contained in a sample has to be distilled off, and after determin- 
ing its strength by the alcoholometer, the content of alcohol in 
the total quantity of fluid ascertained by calculation, or the de- 
termination is effected in a short time and with sufficient accuracy 
for practical purposes by the use of a special apparatus. 

Determination of the Alcohol with the Alcoholometer. 

For the vinegar manufacturer the alcoholometer is an import- 
ant instrument in so far as it serves for quickly ascertaining the 
degrees of the spirits of wine used. It is best to use an in- 
strument which is combined with a thermometer, one being thus 
enabled to ascertain the temperature of the fluid simultaneously 
with reading off the statement of the alcoholometer. Tables I. 
to VIII. appended to this work give the necessary assistance for 



CHEMICAL EXAMINATION OF RAW MATERIALS. 199 

the determination of the actual content of alcohol in a fluid whose 
temperature is above or below the normal temperature (59 F.). 
For the purpose of examining fluids with a very small content 
of alcohol, alcoholometers have been constructed which accurately 
indicate at least 0.1 per cent. For the demands of the fabrica- 
tion of vinegar, four alcoholometers will, as a rule, suffice ; they 
should be so selected that one is to be used for fluids with from 
to 4 per cent, of alcohol, the second for indicating 4 to 8 per 
cent., the third 8 to 12 per cent., and the fourth 12 to 16 percent. 
The scale of such alcoholometers comprising only 4 per cent, each, 
is sufficiently Targe to allow of the easy reading off of one-tenth 
per cent. These instruments serve for the determination of the 
content of alcohol in alcoholic liquid consisting only of spirits of 
wine and water, and are used in examining the progress of the 
formation of vinegar during fabrication. 

Determination of the Alcohol by the Distilling Test. 

The content of alcohol in a fluid containing other bodies be- 
sides .alcohol and water cannot be directly determined by means 
of the alcoholometer, as the statement of the latter would be in- 
correct on account of the foreign bodies exerting a considerable 
influence upon the specific gravity. Hence, the content of alcohol 
in alcoholic liquid containing a certain quantity of acetic acid, or 
of fermented whiskey-mash, beer, wine, etc., cannot be ascer- 
tained by immersing the alcoholometer in the respective fluid. In 
order to determine the content of alcohol in such a fluid a deter- 
mined volume of it is subjected to distillation and the latter con- 
tinued until it may be supposed that all the alcohol present is 
volatilized and again condensed in a suitable cooling apparatus. 
By diluting the fluid distilled over with sufficient water to restore 
it to the volume of the fluid originally used and immersing the 
alcoholometer the content of alcohol is determined. 

A rapid and at the same time accurate execution of all exami- 
nations being of great importance in practice, a suitable apparatus 
should be used for the distilling test. Such an apparatus is 
shown in Fig. 43. It consists of a glass boiling flask, K, having 
a capacity of J liter in which sits by means of a perforated 



erm 



200 



VINEGAR, CIDER, AND FRUIT-WINES. 



cork a glass tube, 7^, which is about f inch in diameter and 7} 
inches in length. On top this tube is closed by a perforated 
cork. From the latter a glass tube bent twice at a right angle 
leads to a cooling coil, which is placed in a vessel, F, filled with 
water, and ends over a graduated cylindrical glass vessel, G. 




Distilliug Apparatus for the Determination of Alcohol. 

The uppermost mark on G indicates the height to which the 
vessel must be filled to contain J liter = 500 cubic centimeters. 
Generally vessels are used which are so graduated that the dis- 
tance between two marks is equal to -$ liter or 50 cubic centi- 
meters. The boiling flask stands upon a plate of thin sheet-iron 
(to prevent bursting from an immediate contact with the flame), 
and together with the cooling vessel is screwed to a suitable sup- 
port. 

In distilling a fluid containing acetic acid the vapors of the 
latter pass over together with those of alcohol and water, and, 
consequently, the statement of the alcoholometer would be in- 
correct. This evil is overcome by placing a few pieces of chalk 
the size of a hazel nut in the tube R. By the vapors coming in 
contact with the chalk the acetic acid is fixed to the lime con- 
tained in it, not a trace reaching the cooling vessel. 

The manner of executing the test with this apparatus is as fol- 



CHEMICAL EXAMINATION OF RAW MATERIALS. 201 

lows : Fill- the vessel G to the uppermost mark with the fluid 
whose content of alcohol is to be examined, then pour it into the 
boiling flask K, rinse out G with water, and after pouring the 
rinsing water into K put the apparatus together as shown in the 
illustration. The contents of K are then heated to boiling by a 
spirit or gas flame under the sheet-iron plate upon which K rests, 
the flame being so regulated that the distillate flows in drops into 
G. By too strong heating the contents of K might foam up and 
pass into G, which would necessitate a repetition of the experi- 
ment with another quantity of fluid. Wine, beer, and whiskey- 
mashes frequently foam up on heating, which can, however, be 
almost completely overcome by the addition of a small quantity 
of tannin solution to the contents in K. 

The heating of the boiling flask is continued until sufficient 
fluid is distilled over into G to fill it from J to J, this being a sure 
indication of all the alcohol present in the fluid having passed 
over. The flame is then removed, the vessel G filled to the 
uppermost mark with distilled water, and the fluids intimately 
mixed by shaking, the mouth of G being closed by the hand. 
The fluid now contained in G consists only of water and 
alcohol, and its volume is equal to that of the fluid originally 
used. By testing the fluid with an alcoholometer the content 
of alcohol found corresponds exactly to that possessed by the 
fluid examined (alcoholic liquid, beer, fermented whiskey-mash, 
etc.). 

Determination of the Alcohol by Means of the EbulUoscope. 

Many determinations of the content of alcohol in the alcoholic 
fluid having to be made in a well-conducted vinegar factory, the 
above-described distilling test is objectionable on account of the 
time (about twenty minutes) required for its execution. Good 
results are, however, obtained by the use of the ebullioscope, and 
but a few minutes being required for the test with this apparatus 
it can be frequently repeated, and thus even a more accurate idea 
of the working of the generators obtained than is possible with a 
single determination by the distilling test. The apparatus is very 
simple, is easily managed, and allows of the direct reading off, 



202 



VINEGAR, CIDER, AND FRUIT- WINES. 



without the use of an aerometer or table, of the content of alcohol 
in a fluid containing not much over 12 per cent. It is much 
used in France for the examination of wine. The principle of 
the apparatus is based upon the initial boiling point of the fluid 
to be examined, an alcoholic fluid boiling at a lower temperature 
the more alcohol it contains. For instance, wine with 

12 per cent, by volume of alcohol boils at 196.7 F. 

10 " " " " " 198.3 " 

8 " " " " 201.0 " 

5 it u 203.3 " 

Fig. 44 shows Vidal-Malligaud's ebullioscope. To a round 
cast-iron stand is screwed a thick-walled brass cup which expands 

Fig. 44. 




Vidal-Malligaud's Ebullioscope. 

somewhat towards the top ; a screw-thread is cut in the upper 
edge. A hollow-brass ring is soldered into the cup near its base, 



CHEMICAL EXAMINATION OF RAW MATERIALS. 203 

one end of the ring entering it somewhat higher than the other. 
On filling the cup with the fluid to be examined this hollow ring 
also becomes filled. On the one side the ring carries -a small 
sheet-iron chimney, and by placing a small spirit-lamp under this 
the fluid in the cup is heated, this arrangement securing a quick 
circulation of the fluid during heating. Upon the upper edge 
of the cup, a lid is screwed, in which a thermometer is inserted 
air-tight. The mercury bulb of the thermometer is on the lower 
side of the lid, and in determining the boiling point dips into the 
fluid. The tube of the thermometer is bent at a right angle out- 
side the lid, the latter carrying the scale, which is divided not 
into degrees but in per cent, by volume of alcohol. The scale 
can be shifted upon a supporting plate so that it can be fixed at 
any desired place, and, consequently, also so that the thermometer 
when dipped into boiling water indicates 0. The scale is secured 
by small screws. Into a second aperture in the lid is screwed the 
cooling pipe which is surrounded by a wide-brass tube for the 
reception of the cooling water. During the determination of the 
alcohol, which requires about ten minutes, the cooling water need 
not be renewed, the boiling point remaining constant during the 
short time (one to two minutes) necessary for making the obser- 
vation. In heating wine the gases and besides a few light 
volatile varieties of ether, as acetic ether, aldehyde, ethylamine, 
propylamine, and similar combinations escape through the cooling 
pipe which is open on top, and in heating beer, carbonic acid. 
For the determination of the alcohol in sacchariferous wines, the 
ebullioscope is less adapted, nor does it give accurate results with 
the use of dilute wines. 

It has been ascertained by the French Academy that the state- 
ments of the ebullioscope as regards the quantity of alcohol in 
the wine differ on an average ^ per cent, from those found by 
accurate distillation. The entire apparatus with the exception of 
the thermometer being of metal, it is not liable to breakage. 
The mercury bulb of the thermometer is comparatively large. 
For the vinegar manufacturer the ebullioscope is a very valu- 
able instrument, as it enables him to accurately determine to with- 
in 1 per cent, the content of alcohol in a fluid in a shorter time 
than is possible with any other instrument. Its use is especially 



204 VINEGAR, CIDER, AND FRUIT-WINES. 

recommended when the working of one or more generators is to 
be ascertained in a short time, perfectly reliable results being ob- 
tained in connection with the determination of the acid by titra- 
tiou. 

Determination of the Content of Acetic Anhydride in Vinegar, or 

Acetometry. 

The content of acetic acid in vinegar is sometimes ascertained 
by a species of hydrometer termed an acetometer. The statements 
of these instruments are, however, very unreliable. Vinegar 
made from dilute alcohol or ripe wines in which no great excess 
of albuminous or other matter is present might to a certain limit 
be tested with sufficient accuracy by the acetometer, but vinegars 
made from malt, poor wines, and such liquids as contain au ex- 
cess of organic matters, do not admit of being tested with the 
required degree of accuracy by this method, since the apparent 
quantity of real acetic acid is increased by the presence of foreign 
bodies which add to the density of the liquid. In some cases the 
vinegar is saturated with chalk or milk of lime, the solution fil- 
tered, and the specific gravity of the acetate of lime liquor ascer- 
tained, by which a nearer approximation is arrived at than by 
the direct testing of the vinegar, yet implicit reliance cannot be 
placed on either of these two methods. 

The best method of ascertaining the percentage of acetic acid 
in vinegar is by titration or volumetric analysis. For the execu- 
cutiou of the test a few instruments are required, which shall be 
briefly described as follows : For measuring off small quantities 
of liquids, serve a burette and pipette, the latter a glass tube of 
the form shown in Fig. 45. It is filled by dipping the lower 
end into the liquid and sucking on the upper with the mouth 
until the liquid has ascended nearly to the top. The upper end 
is then quickly closed with the index finger of the right hand. 
By slightly lifting the finger, the liquid is then allowed to flow 
off by drops until its level has reached a mark above the convex 
expansion, when it will contain exactly the number of cubic cen- 
timeters indicated opposite to the mark. 

The burette is a cylindrical glass tube open on the top, gradu- 



CHEMICAL EXAMINATION OF RAW MATERIALS. 



205 



ated, commencing from the top, into whole, one-tenth, and one- 
fifth cubic centimeters. The lower end of the tube is drawn out 



Fig. 45. 



Fig. 46. 




to a somewhat distended point, so as to allow a rubber tube to be 
drawn over it and securely fastened. In the lower end a glass 



200 



VINEGAR, CIDER, AND FRUIT-WINES. 




tube drawn out to a fine point is inserted. The rubber tube is 
compressed in the centre by a pinch-cock or clip, whereby the 

lower end is closed. Fig. 46 
shows a burette secured in a 
stand and Fig. 47 the lower 
part, with the clip on a larger 
scale. The burette is filled 
with liquid from above by 
means of a small funnel. By 
a quick, strong pressure upon 
the handle-joint of the clip, 
some liquid is then allowed 
to flow in a jet into a vessel. 
By this the tube below the 
clip is filled with liquid -and 
the air contained in it ex- 
pelled. By a slight or stronger 
pressure the liquid can, after 
some experience, be ejected in 
drops or in a stronger jet. 
The number of cubic centi- 
meters which have been al- 
lowed to flow out can be 
readily read off by keeping 
the surface of the fluid in the 
tube on a level with the eye. 
The test liquor generally used 
is normal caustic soda solu- 
tion, one cubic centimeter of it 
corresponding to 0.06 gramme 

of acetic anhydride, and for especially accurate determinations de- 
cinormal solution, one cubic centimeter of it corresponding to 
0.006 gramme of acetic anhydride and y 1 ^ cubic centimeter to 
0.0006 gramme. 

For determining the acetic acid the burette is filled to the O 
point with soda solution ; a corresponding quantity of vinegar is 
then accurately measured off by means of the pipette, and after 
bringing it into a beaker, colored red by the addition of one or 




CHEMICAL EXAMINATION OF RAW MATERIALS. 207 

two drops of litmus tincture and diluted with four to six times 
its quantity of distilled water. The beaker is placed upon a 
Avhite support under the burette and the soda solution in the 
latter ejected in a strong jet by pressing with the right hand the 
handle-joint of the clip, the fluid being constantly agitated by 
gently swinging the beaker with the left. The influx of soda 
solution is interrupted as soon as a blue coloration on the point 
where it runs in is observed. After thoroughly stirring the fluid 
with a glass rod, the soda solution is again allowed to run in, but 
now drop by drop, the fluid being stirred after the addition of 
each drop. This is continued until the fluid has acquired a violet 
color with a strong reddish shade, and the addition of one drop 
more of soda solution changes the color to blue. The appearance 
of the violet coloration is called the neutralizing point, while the 
change of color from violet to blue indicates that the fluid is now 
neutral, i. e., contains neither free acetic acid nor an excess of 
caustic soda. The determination is based upon the coloring sub- 
stance of litmus appearing red in acid, violet in neutral, and blue 
in alkaline solutions. 

Instead of soda test liquor a solution of ammonia is sometimes 
used to saturate the acid. The solution is prepared by adding 
water to concentrated ammonia till the specific gravity is 0.992 ; 
1000 grains of this dilute ammonia contain one equivalent of am- 
monia, which is capable of saturating one equivalent of acetic 
acid. The application of this test is similar to that already de- 
scribed. 

There is some difficulty in preserving the dilute ammonia of 
the same strength, which is an objection to its use ; but a uni- 
formity of concentration may be insured by introducing into the 
bottle two glass hydrometer bulbs so adjusted that one remains 
barely touching at the bottom, and the other floats just under the 
surface of the liquid as long as the test liquor retains the proper 
strength. If a part of the ammonia volatilizes, the specific 
gravity of the liquor will become proportionally greater, and the 
glass bulbs rise ; the lower one higher from the bottom, and the 
upper one partly above the surface. When this happens, more 
strong ammonia is added, till the hydrostatic drops are properly 
readjusted. 



208 



VINEGAR, CIDER, AND FRUIT- WINES. 



Fig. 48. 



Determinations of acetic acid by titration having to be fre- 
quently executed in a vinegar factory it is advisable to use an 
apparatus which will facilitate the operation. Such an ap- 
paratus is shown in Fig. 48. Upon a table stands a two-liter 
flask holding the normal soda solution. The 
flask is closed air-tight by a cork provided 
with three perforations. In one of these per- 
forations is inserted a glass-tube, A, in the 
lower end of which is a stopper of cotton upon 
which are placed small pieces of burnt lime. 
On top, the tube is closed by a glass-tube drawn 
out to a fine point. Through another of these 
perforations passes a glass-tube, jR, bent twice 
at a right angle and reaching to the bottom of 
the flask ; the portion of this tube outside of 
the flask, as will be seen in the illustration, is 
somewhat longer than that in the flask, and, 
consequently, the tube forms a siphon. The 
outside portion of this tube is connected by a 
short rubber tube with the upper portion of 
the burette B. The latter is secured in a ver- 
tical position by two rods placed on the stand 
holding the flask. Below the burette is con- 
nected with a short rubber tube in which is in- 
serted a glass-tube drawn out to a fine point. 
On the side near the top of the burette is a small tube bent at a 
right angle, which is connected by a short rubber tube with the 
tube L, the latter reaching only to below the edge of the cork. 
Above and below the burette is closed by the clips Q and Q L . 

For working with the apparatus the flask is filled with normal 
soda solution and the cork inserted air-tight after removing from 
it the tube A and substituting for it a small glass-tube. Now 
open the upper clip Q and blow vigorously through the glass- 
tube substituted for A, whereby the fluid is forced through the 
tube R into the burette. This being done cease to press upon Q, 
whereby the latter closes and stops a further discharge of the 
fluid. The tube, A, is then placed in position. By now pressing 
on the clip Q the fluid passes into the burette, the air contained 




EXAMINATION OF VINEGAE. 209 

in the latter entering the flask through the tube L. The burette 
being emptied by the discharge of the fluid through Q 19 it is re- 
filled for another determination of acid by simply pressing on Q, 
and this can be repeated as long as the flask contains soda solu- 
tion. 

In discharging the fluid from the burette by opening Q v air 
from the outside passes into the apparatus through A. In doing 
so it must, however, pass through the line which fixes the car- 
bonic acid contained in it, so that the fluid in the flask remains 
free from carbonic acid even after standing for months. 

The calculation of the quantity of acetic acid present in 
the vinegar examined is made as shown by the following ex- 
ample : 

For 10 cubic centimetres of vinegar were consumed 70 cubic 
centimetres of decinormal soda solution. 

One cubic centimetre of decinormal soda solution being equal 
to 0.006 gramme of acetic acid, hence 70 cubic centimetres 
0.42 gramme. 

Now, as 10 cubic centimetres contain 0.42 gramme of acetic 
acid, 100 cubic centimetres contain 10 times 0.42 gramme 4.2 
grammes of acetic acid; or the vinegar examined contains 4.2 per 
cent, by weight of acetic acid. 



CHAPTER XX. 

EXAMINATION OF VINEGAR AS TO THE PRESENCE OF FOR- 
EIGN ACIDS AND OF METALS, AS WELL AS TO ITS DERIVA- 
TION. 

Detection of Acids. 

SOME unscrupulous manufacturers, in order to pass off weak 
or inferior vinegars, adulterate them with mineral acids. Such 
adulteration is not only a fraud, but dangerous to health, and it 
is necessary to indicate the means by which such additions can 
be detected. 
14 



210 VINEGAR, CIDER, AND FRUIT-WINES. 

Sulphuric acid Add to a sample of the vinegar a few drops 
of a solution of barium chloride. If the vinegar becomes slightly 
cloudy, the impurities are due to sulphates naturally present in 
the water or in the substances from which the vinegar has been 
made. A heavy white cloud slow in subsiding will indicate free 
sulphuric acid in small proportion. If the quantity of sulphuric 
acid is more than a thousandth, the sulphate of baryta produces a 
precipitate and falls rapidly to the bottom of the test-glass. 

The presence of free sulphuric acid in vinegar can also be de- 
termined by coating a porcelain plate with strong sugar solution 
and allowing the latter to dry up. By bringing a few drops of 
vinegar to be examined upon the plate and placing the latter in 
a moderately warm place, pure vinegar evaporates, leaving a 
slightly brownish stain ; vinegar containing free sulphuric acid 
leaves a dark-brown stain which on heating the plate turns 
black. 

The presence of free sulphuric acid in vinegar can be deter- 
mined with still greater sharpness by the following test : Divide 
a piece of starch the size of a grain of wheat in 50 cubic centi- 
metres of vinegar and reduce the fluid one-half by boiling. To 
the clear fluid cooled to the ordinary temperature add a drop of a 
solution of iodine in spirits of wine. Vinegar containing no free 
sulphuric acid at once acquires a blue coloration ; if free sulphuric- 
acid be present, the fluid remains colorless. This test is based 
upon the fact that starch by continued boiling with sulphuric acid 
is converted into dextrin and finally into sugar. Neither of these 
bodies reacts upon iodine, while a very small quantity of starch 
gives with iodine the characteristic blue coloration. 

Hydrochloric acid. Take about 100 cubic centimetres of the 
vinegar to be tested and distill off one-half by means of the ap- 
paratus Fig. 43, p. 200. Compound the fluid distilled off with a 
few drops of solution of nitrate of silver. In the presence of 
hydrochloric acid a white, caseous precipitate is immediately 
formed which consists of chloride of silver and dissolves in liquid 
ammonia added in excess. 

Nitric acid is not a frequent adulteration. It is detected by 
saturating with carbonate of sodium or of potassium several 
ounces of vinegar and evaporating the whole to dryness. The 



EXAMINATION OF VINEGAR. 211 

addition of sulphuric acid and copper turnings will cause the 
evolution of nitrous vapors if nitric acid be present. 

Lactic acid. In many varieties of vinegar small quantities of 
lactic acid occur, which can be detected by slowly evaporating 
1 00 cubic centimetres of vinegar in a porcelain dish until but a 
few drops remain. If these drops show a very strong pure acid 
taste, the vinegar examined contains lactic acid. The presence of 
lactic acid is, however, not due to an intentional addition, but to 
the material used in the manufacture of the vinegar, that prepared 
from grain^ malt, or beer always containing it. 

Sulphurous acid. This acid occurs only in vinegar prepared 
by fermentation when stored in freshly sulphured barrels. It 
may, however, occur in vinegar whose content of acetic acid has 
been increased by the addition of high graded acetic acid prepared 
from wood-vinegar. The most simple method of detecting the 
presence of sulphurous acid is by placing 100 cubic centimetres 
of the vinegar to be examined in a glass-distilling apparatus, and 
connecting the latter by a gas-tube with a vessel containing 50 
cubic centimetres of pure water compounded with about 10 drops 
of nitric acid. After distilling over ^ of the vinegar the acidu- 
lated water is heated to boiling for a few minutes and solution of 
barium chloride added. If the vinegar contains sulphurous acid, 
a heavy white precipitate is formed. 

Detection of Petals. 

The occurrence of metals in vinegar is due to the vessels em- 
ployed in the manufacture or the storage, and, hence, the use of 
metallic utensils, such as stop-cocks, pumps, etc., should be avoided 
as much as possible. Besides iron, copper, zinc, and tin are occa- 
sionally found in vinegar. 

Iron. The presence of this metal imparts a black color to the 
vinegar, which is increased by a few drops of tincture of gall-nuts. 
If the color of vinegar compounded w T ith a few drops of solution 
of tannin is not changed after standing a few hours, the vinegar 
contains no iron, or only so small a quantity as to be of no im- 
portance. 

Copper. While the presence of a small quantity of iron is of 



212 VINEGAR, CIDER, AND FRUIT-WINES. 

little importance in a hygienic respect, that of copper, zinc, or tin 
is more serious, the combinations of these metals having a poison- 
ous effect upon the organism. Copper can be detected in vinegar 
by evaporating to dry ness about 1 quart of the vinegar to be 
examined and dissolving the residue in a few drops of nitric acid. 
By compounding a portion of this solution with ammonia in 
excess the fluid acquires a perceptible blue coloration in the 
presence of copper; the latter can be shown with still greater 
sharpness by dipping polished iron into another portion of the 
fluid. If the iron becomes coated with a perceptible red film 
(consisting of actual copper), the presence of this metal is shown. 
Tin. Evaporate to dryness at least 2 or 3 quarts of the vine- 
gar ; dissolve the residue in hydrochloric acid, and conduct sul- 
phuretted hydrogen through it until the fluid has acquired a 
strong odor of the latter. If a precipitate is formed, it is filtered 
off, dissolved in strong hydrochloric acid, and the solution divided 
into several portions. Compound one of these portions with 
dilute solution of chloride of gold ; if after some time it becomes 
rod and precipitates red flakes, the vinegar contains tin. The 
presence of tin is also indicated if another portion of the solution 
of the precipitate in hydrochloric acid does not acquire a blue 
color after the addition of potassium ferrocyanide. The behavior 
of the fluid towards solution of potassium permanganate may 
serve as a controlling test ; if the fluid contains tin, the solution 
of potassium permanganate becomes discolored. 

Determination of the Derivation of a Vinegar. 

The examination of a vinegar as regards the materials used in 
its preparation is generally effected by the senses of odor and taste ; 
there are, however, many easily executed tests which assist the 
judgment of the tongue and nose. 

Vinegar prepared from dilute spirits of wine is colorless or only 
colored slightly yellowish. If such vinegar has a dark yellow 
color resembling that of wine, it is generally due to the addition 
of sugar color, the addition being chiefly made on account of the 
erroneous opinion prevailing among the public that vinegar clear 
as water or only slightly colored lacks strength. 



EXAMINATION OF VINEGAK. 213 

Vinegar prepared from spirits of wine leaves, when carefully 
evaporated in a porcelain dish, a very small residue of a whitish 
or very slight yellow color, which chiefly consists of the salts 
contained in the water used for the preparation of the alcoholic 
liquid, an accurate examination showing it to consist of calcium 
acetate, gypsum, and a very small quantity of sodium chloride. 
If the residue is of a dark brown color, swells up when heated, 
and leaves a lustrous black coal, the vinegar has been colored 
with sugar color. 

Beer and malt vinegars are dark yellow, generally with a red- 
dish shade. On account of their content of dextrin they foam 
when shaken, and, when carefully evaporated, leave a brown, gum- 
like residue. The latter consists chiefly of dextrin, and contains, 
besides, the other extractive substances occurring in beer and 
malt vinegar, such as salts of ashes, especially much phosphoric 
acid. On heating strongly an odor calling to mind that of 
toasted bread is evolved. At a still higher temperature the resi- 
due turns black and finally acts like caramel : it evolves pungent 
vapors and leaves a lustrous coal. 

The great content of phosphoric acid characteristic of malt or 
beer- vinegar may also serve for the determination of the deriva- 
tion of such vinegar. By compounding beer or malt- vinegar 
with some nitric acid and a solution of ammonium molybdate 
and heating, the fluid, after standing, separates a yellow precipi- 
tate, which contains the phosphoric acid present in the fluid. 

Wine-vinegar is best recognized by its characteristic odor, the 
latter becoming especially perceptible by rinsing out a large tum- 
bler with the vinegar, and after allowing it to stand for a few hours 
examining the odor of the few drops remaining in the tumbler. 
The greater portion of the acetic acid having then volatilized 
the vinous odor becomes more prominent. Cider-vinegar, the 
odor of which is somewhat similar to that of wine-vinegar, can 
in this manner be plainly distinguished from the latter, the residue 
in the tumbler having an entirely different odor. 

The presence of potassium bitartrate is a characteristic sign 
of wine-vinegar. By evaporating wine-vinegar to a brownish 
syrupy mass, boiling the latter with some water, rapidly filter- 
ing the boiling fluid into a test tube, and adding double its volume 



214 VINEGAR, CIDER, AND FRUIT-WINES. 

of strong spirits of wine, a sand-like precipitate falls to the bottom 
of the test-tube, which consists of very small crystals of tartar. 
This, however, does not prove the sample to be genuine wine- 
vinegar, tartar also being contained in imitations. With a suffi- 
ciently sharp sense of smell this is, however, the surest means of 
distinguishing genuine wine-vinegar from a spurious article. 

In case the derivation of a vinegar is to be established with 
absolute certainty it has to be subjected to an accurate chemical 
analysis, and this being better made by an analytical chemist 
onlv a few hints are here given which may serve as a guide for 
such analyses. 

In a vinegar prepared from a fermented fluid a certain quantity 
of glycerin and succinic acid will, as a rule, be present, these bodies 
being ahvavs formed bv the fermentation of a sacchariferous 

* 

fluid, and, consequently, when found, the respective vinegar can- 
not have been prepared from an alcoholic liquid consisting only of 
spirits of wine and water. If they are found only in very small 
quantities, the alcoholic liquid used for the fabrication of the vine- 
gar consisted very likely of spirits of wine and water with the 
addition of beer or fermented whiskey-mash, and in this case 
small quantities of dextrin and of phosphates will also be found. 
The total absence of tartaric acid and the presence of malic acid 
indicate the derivation of the vinegar under examination from 
fruit, though not necessarily from apples or pears, other saccha- 
riferous fruits also containing malic acid. A content of tartaric 
acid is, however, no proof of genuine wine-vinegar, as its presence 
may be due to an intentional addition, and it is very difficult to 
arrive at a certain conclusion about the genuineness of a pre- 
tended wine-vinegar, especially in the case of cider-vinegar to 
which tartaric acid has been added. 

Should pepper, chillies, etc., be added to vinegar for the pur- 
pose of conferring more pungency, they may be detected by neu- 
tralizing the acid with carbonate of soda and tasting the liquor; 
if these bodies be present, the solution will still retain the sharp- 
ness peculiar to such spices. 



MANUFACTURE OF WOOD-VINEGAR. 215 



CHAPTER XXI. 

MANUFACTURE OF WOOD-VINEGAR. 

AMONG the numerous organic substances which by distillation 
in -closed vessels give rise to acid products, wood is employed in 
the arts for the manufacture of acetic acid. "Wood-vinegar, or 
acetic acid from wood, is also known when impure under the 
name of pyroligneous acid. 

Wood essentially consists of woody fibre, small quantities of 
salts and sap, and a variable quantity of hygroscopic water. 
Woody fibre or cellulose constitutes about 96 per cent, of dry 
wood, and is composed of C 6 H 10 O 5 ; in 100 parts, of carbon 
44.45; hydrogen 6.17; oxygen 49.38. The vegetable sap con- 
sists chiefly of water, but contains organic as well as inorganic 
matters, partly in solution and partly suspended. The inorganic 
constituents (the ash left after the incineration of the wood) arc 
the same in all kinds of wood. The quantity of water contained 
in wood is generally larger in soft than in hard woods. One 
hundred parts of wood recently felled contain, according to 
Schubler and Xeuffer, the following quantities of water : 



Beech .... 18.6 
Birch . . . .30.8 
Oak .... 34.7 

Oak (quercus pedunculata) 35.4 
White fir 37.1 



Common fir . . .39.7 
Red beech . . .39.7 
Alder .... 41.6 
Elm .... 44.5 

Red fir , 45.2 



The branches always contain more water than the trunk. 

Wood is called air-dry when its weight no longer changes at 
an ordinary temperature ; in this state it contains still 1 7 to 20 
per cent, of water. The latter can be expelled by continued 
heating at 212 F., but wood thus dried re-absorbs about 20 per 
cent, of water from the air. 

When felled nearly all kinds of wood are lighter than water ; 
a few are, however, heavier, but these are the harder kinds in which 



216 VINEGAR, CIDER, AND FRUIT-WINES. 

the cellulose is so closely packed that very little room is left for 
the retention of air. The following table exhibits approximately 
the specific gravity of various woods : 



T 1 


47 


Ash . 


. 0.64 


Fir and pine . 
Beech 
Birch 


. 0.55 
. 0.59 
. 0.62 


Oak 
Hornbeam 


. 0.70 
. 0.76 



The content of ash is not the same in all woods; it varies 
considerably in different parts of the same tree and also with its 
age. According to Violet, in the cherry tree the content of ash 
is greatest in the leaves (about 7 per cent.), next in the lower 
parts of the roots (5 per cent.) ; considerably greater in the bark 
than in the Wood, in the former from 1.1 to 3.7 per cent., and in 
the latter 0.1 to 0.3 per cent. Saussure found in the bark of the 
oak 6 per cent., in the branches 0.4 per cent., and in the trunk 
0.2 per cent, of ash. The ash consists chiefly of carbonates of 
calcium, potassium, and sodium, further of magnesia and the 
phosphates of different bases. 

The average composition of 100 parts of air-dry wood is : car- 
bon 39.6 parts, hydrogen 4.8, oxygen and nitrogen 34.8, ash 0.8, 
hygroscopic water 20 ; and that of artificially dried wood : car- 
bon 49.5, hydrogen 6, oxygen and nitrogen 43.5, ash 1. 

Decomposition of u-ood. Cellulose when carefully treated re- 
mains unchanged for a long time, even thousands of years. Wood 
is, however, subject to greater changes, though under especially 
favorable circumstances it may last for several centuries. In the 
presence of sufficient moisture and air the nitrogenous bodies of 
the sap are, no doubt, first decomposed, and the decomposition 
being next transferred to the woody fibre, the latter gradually 
loses its coherence, becomes gray, then brown, and finally decays ; 
hence, wood rich in water decays more rapidly than dry wood. 

Wood to be preserved should, therefore, be as dry as possible, 
and the nitrogenous bodies, which can be but incompletely re- 
moved by lixiviatiou, be converted into insoluble combinations ; 
tar and one of its most effective constituents creasote mercuric 
chloride, blue vitriol, chloride of zinc, and many other substances 
having been recommended for this purpose. Moreover, it has been 
successfully attempted to produce certain insoluble bodies, such 



MANUFACTURE OF WOOD- VINEGAR. 217 

as aluminium and copper soaps, in the interior of the wood by 
saturating it with soda soap and then with aluminium chloride or 
blue vitriol, or such as barium phosphate by saturating with 
sodium phosphate and then with barium chloride,, etc. 

By heating to 212 F. the wood remains unchanged; it 
yields up only sap constituents. If, however, the temperature be 
increased, for instance to 392 F., a small quantity of sugar is, 
according to Mulder, formed from cellulose in a closed vessel, 
and from wood, according to G. Williams, an acid not yet 
thoroughly known, methyl alcohol (see further on), an oil boiling 
between 277 and 421 F. and a small quantity of furfurol. 

In the presence of water, wood in a closed vessel is, however 
already decomposed at about 293 F., if this temperature be 
kept up for a long time, for instance, a month, the wood, accord- 
ing to Sorby, being converted into a lustrous black mass with 
the formation of acetic acid and gases. 

According to Daubree, pine, when heated for some time with 
water in an entirely closed vessel to 752 F., is converted into a 
mass having the appearance of stone-coal and approaching an- 
thracite in its behavior. Baroulier made similar observations, 
masses resembling stone-coal being formed by pressing sawdust, 
stems, and leaves together in moist clay and heating continuously 
to from 392 to 572 F., so that the vapors and gases could 
escape only very slowly. 

By avoiding all heating concentrated sulphuric acid converts 
cellulose into a gum-like body, dextrin, which by diluting with 
water and long digesting is converted into sugar (starch sugar) ; 
when heated the wood, however, turns black with development of 
sulphurous acid and complete destruction. By dilute sulphuric 
acid cellulose is converted into starch, or at least a starch-like 
body colored blue by iodine and dextrin. Wood is, however, but 
little affected by it at an ordinary temperature, while at a higher 
temperature a certain quantity of sugar (starch sugar) is formed, 
water being absorbed at the same time. This behavior has been 
utilized for obtaining alcohol by fermenting the sugar with yeast 
after neutralizing the acid by calcium carbonate, for instance, 
chalk. The unattacked woody fibre can be used as material for 
paper. 



218 VINEGAR, CIDER, AND FRUIT- WINES. 

Concentrated hydrochloric acid colors wood rose color to violet 
red and then rapidly destroys it. Dilute hydrochloric acid, on 
heating, forms sugar ; but, according to Zetterlund, the quantity 
of absolute alcohol obtainable in this manner is very small, 
amounting to about 2.3 per cent, of the weight of the wood.* 
By macerating wood with dilute hydrochloric acid at an ordinary 
temperature, the cellulose is not changed, but the so-called lignin 
seems to be dissolved. By forcing dilute hydrochloric acid by a 
pressure of two atmospheres into trunks provided with the bark, 
and subsequent washing out in the same manner with water, and 
drying by means of a current of air at 98.6 F., wood acquires 
great plasticity. In a moist state wood thus treated can be 
pressed together to one-tenth of its original volume. 

Hydriodic acid reduces the wood to several hydrocarbons, 
water being formed and iodine liberated. 

Concentrated nitric acid, or, still better, a mixture of it and 
sulphuric acid, converts cellulose, for instance, cotton, into gun- 
cotton ; wood is colored yellow and partially dissolved. Dilute 
nitric acid, for instance, of 1.20 specific gravity, has no effect in 
the cold, and but little when heated. 

By bringing cellulose in contact with dilute aqueous solutions 
of alkalies, it is colored blue by iodine, and consequently a starch- 
like substance is formed, but no humus-like bodies ; from wood 
only the lignin is extracted, the woody fibre remaining unchanged. 
By heating with strong alkaline lyes, or, still better, by fusing 
with solid caustic alkalies, acetic acid is, according to Braconnot, 
first formed and then oxalic acid. The latter acid is frequently 
obtained by this process. 

On heating shavings with sodium sulphide an abundant quan- 
tity of acetic acid (sodium acetate) is formed ; the addition of 
sulphur to caustic soda seems to have the effect of preventing the 
formation of oxalic acid. 

< According to prior experiments by Bachet, it is, however, claimed that 
up to 23 per cent, of sugar can be obtained from wood by boiling 10 to 12 
hours with water containing one-tenth of hydrochloric acid. 



MANUFACTUKE OF WOOD- VINEGAR. 219 

Decomposition of Wood at a Higher Temperature. 

All organic bodies, except those which sublime without change, 
are decomposed when exposed to heat in closed vessels, their con- 
stituents interchanging with one another and forming new com- 
pounds, which are of sufficient stability to resist the particular 
temperature employed. Thus, the elementary components of 
wood, after a certain amount of heat is applied, arrange them- 
selves into combinations quite distinct from those in which they 
originally were. Some of them are gaseous, but at moderate 
temperatures by far the greater part are liquid, the quantity of 
the latter depending entirely upon the greater or less degree of 
heat applied in this distillation. 

The main cause of decomposition of such an organic body as 
wood by heat is that the strong affinity of its contained oxygen 
for carbon and hydrogen and the comparatively greater stability 
of the more simple compounds of these bodies, cause their for- 
mation the moment there is a sufficient amount of commo- 
tion amongst the atoms of the original body to allow them to 
commingle freely. Heat sets up the necessary vibration, and 
those compounds are at once formed which can resist without 
rupture of their constituents from each other, the multitude or 
amplitude of the vibrations corresponding to the temperature at 
which they are evolved. 

As a general rule, those bodies containing much oxygen are 
decomposed at comparatively low temperatures. Acetic acid is 
an exception ; a dull red heat does not cause its constituents to fly 
sufficiently apart from each other to cause their total separation, 
and the compound, therefore, remains unchanged. To this cir- 
cumstance is due the large amount of acetic acid which is pro- 
duced during the destructive distillation of wood. As previously 
stated, the composition of cellulose is C 6 H 10 O 5 . The hydrogen 
and oxygen being in the proportions to form water, the with- 
drawal of carbon would form acetic acid thus : 2C 6 A 10 O 3 2C 
= 4C 2 H 4 O 2 . As might be anticipated, acetic acid is amongst 
the earliest and most abundant products of the distillation of 
wood, and, being volatile, escapes decomposition at the higher 
temperatures employed later. As the distillation progresses, 



220 VINEGAR, CIDER, AND FRUIT-WINES. 

marsh gas (CH 4 ), olefiant gas (C 2 H 4 ), tetrylene (C 4 H 8 ), and 
volatile oils, such as benzol (C 6 H 6 ), toluol (C 7 H 8 ), naphthalin 
(C 10 H 8 ), paraffin (C 20 H 42 ), phenol (C 6 H 6 O), etc., are given off. 
The actual facts which are observed in the distillation of wood 
are as follows : 1. The water passes off which is extraneous to 
the wood ; 2. The wood itself is decomposed and gives rise to 
water and the crude acetic acid, which is next eliminated; 3. 
Condensable matters containing an excess of carbon forming the 
tar and oily substance pass over ; 4. Toward the close of the 
operation, carbonic oxide and marsh gas are evolved, leaving in 
the retort a charcoal similar in form to the wood introduced. 



Distillation of Wood. 

The distillation of wood is carried on in retorts made of cast- 
iron or wrought-iron, and sometimes of clay. The latter have 
the advantage of not burning through, but it is difficult to keep 
them entirely tight, a number of small cracks being formed 
through which a portion of the vapors escapes. Cast-iron re- 
torts do not readily burn through, and are but little affected by 
the vapors of the acid, but they frequently burst, and defective 
places are difficult to repair. Wrought-iron retorts gradually 
burn through on the bottom, where they come in contact with the 
fire ; they can, however, be repaired by riveting strong boiler- 
plate upon the defective place, and are less affected by the acetic 
acid vapors than might be supposed, because some protection is 
afforded to them by the deposition of a layer of coal from de- 
composed tar vapors and gases upon their interior surface. Ex- 
perience having shown that wrought-iron is more strongly 
attacked on the less hot places than on the hottest, it is customary 
to provide wrought-iron retorts with cast-iron doors and discharge 
apertures. To retard burning through, the exterior of the re- 
torts is coated with a thick layer of lime or clay, or with a mix- 
ture of lime, iron-filings, and water glass. The riveting must 
be carefully executed, and the joints luted with clay or trass- 
mortar. 

Form of the retorts. Clay-retorts are mostly Q -shaped like 
those for the manufacture of coal-gas. 



MANUFACTURE OF WOOD-VINEGAR. 221 

Cast-iron retorts are either cast in one piece, having in this case 
a cylindrical form with a circular cross section, or flat pieces 
are connected together by screws to parallelepiped boxes ; the lat- 
ter form is preferable for the distillation of birch bark, which fills 
up the room to the best advantage by placing it in flat, even pieces. 

Dimensions of the retorts. The size of the retorts varies greatly, 
but the most suitable for horizontal cast-iron or wrought-iron re- 
torts is a length of from 5J to 6 J feet with a diameter of from 2 J 
to 3J feet. In England retorts of a still greater size are in use, 
for instance, wrought-iron ones, which with a length of 6-J feet 
have a diameter of 4J feet, and cast-iron ones with a length 
of from 8f to 9J feet and a diameter of 3 feet. AVrought-iron 
retorts are generally from 0.27 to 0.31 inch thick. 

For vertical wrought-iron retorts Vincent recommends a height 
of 6 feet and a diameter of 4 feet, and Gillot, as well as Rothe, a 
diameter of from 4 to 5 feet and a height of 7 \ feet. 

For rectangular wrought-iron boxes : length 4J feet, width 
2.62 feet, height 3.28 feet. For rectangular cast-iron boxes : 
length 8.85 to 9.18 feet, width 3.28 to 4 feet, height 4 to 4j- 
feet. 

Position of the retorts. In France vertical wrought-iron cylin- 
drical or rectangular boxes are most frequently used. This 
arrangement allows of the vessel, when distillation is finished, 
being lifted from its position by means of a crane and inserting a 
new one in its place, so that the high temperature which the brick 
work has acquired is utilized almost without loss. The disadvan- 
tage is the inconvenient filling and emptying of such vessels, both 
operations having to be executed from above. To facilitate the 
emptying, an aperture is occasionally provided near the bottom, 
but in this case it is difficult, on account of the high temperature, 
to make the aperture tight by a clay luting. Further, the va- 
pors escaping from the lower portion of the wood to be distilled, 
especially those specifically heavier than tar, rise only with diffi- 
culty to the discharge aperture, and having consequently to re- 
main an unnecessarily long time in the hot space are partially 
decomposed to permanent gases. Even with the best condensing 
apparatus they carry along a certain quantity of acetic acid and 
especially of wood spirit, and the non-condensing portion is then 



222 



VINEGAR, CIDER, AND FRUIT-WINES. 



only used as fuel. This evil could be overcome by providing a 
discharge aperture for the heavier vapors on the lower half of 
the retort ; but this has again the disadvantage that the exchange 
of the hot vessels cannot be effected as rapidly. 

In England and Germany horizontal retorts, which are uni- 
formly surrounded by the flame, are in general use. To prevent 
a disadvantage similar to the one mentioned above, the retorts, 
however, must not be too long, as the vapors from the front have 
to pass over the glowing back portion to reach the discharge 
aperture. 

Vertical retorts. Fig. 49 shows Kestner's apparatus, which is in 
extensive use in France. The retort a has a capacity of 3 cubic me- 
ters (105.94 cubic feet). It is surrounded by flues which lead to the 
chimney t. Large sticks are set upright in the retorts ; those too 
thick should be split, and small wood packed close. The retort 
is closed at the top by an iron cover secured by screws or clamps. 

Fig. 49. 




The products of distillation are condensed in the copper pipes b, 
which are inclosed in wider cast-iron or copper pipes d. In the 
latter a current of water passes from e through the connecting pipe 
/ from below to above, and effects the cooling off of the vapors. 
The non-condensed vapors and gases are conducted through c 



MANUFACTURE OF WOOD-VINEGAR. 



223 



into the fire-place. The pipe conducting the wood-vinegar and 
the tar into the vats h dips somewhat into the fluid. From the 
vats the fluids are pumped into large reservoirs placed at a, 
higher level, so that they can be readily discharged into the stills. 

The apparatus is not movable, i. e., the retort remains fixed in 
its place. 

Movable retorts, as shown in Fig. 50, were first introduced in 
France. They are entirely surrounded by the fire gases, the fire- 
place being closed on the top by a brick cover held together by 
means of iron hoops. The vapors and gases pass out through 
the pipe a which is placed on the side immediately below the 
cover. When no more volatile products appear the lid is removed, 

Fig. 50. 




and, after interrupting the connection with the condenser, and 
closing the pipe a with clay, the glowing retort is lifted out by 
means of a crane. A new retort already filled with wood is then 
immediately placed in the hot furnace and distillation recom- 
menced. The pipe b conducts the non-condensed vapors and 
gases into the fire-place. 

In modern times this apparatus has been modified, as shown in 
Fig. 51, and in this form is in general use in France. The de- 
veloping pipe for the volatile products has been transferred to the 



VINEGAR, CIDER, AND FRUIT-WINES. 

lid. The fire-place has the form of a truncated cone, and the 
retort is surrounded by it only to about five-sixths of its height, 
while the upper end projects about one foot. The movable cover 
being omitted the exchange of the retorts is facilitated. The 
brick work of refractory material is held together at the top by 
a strong iron ring. The bottom of the fire-place is formed by an 
arch below which is the hearth whose flames surround the curved 
surface as well as the bottom of the retort. At the top the fire- 
Fig. 51. 




place is terminated by an iron ring placed on the retort. To save 
fuel the fire-place serves for two retorts, as shown in the illustra- 
tion. 

The fire burns constantly upon the hearth ; it is regulated by 
means of two registers placed in the upper end of the fire-place 
in the draught apertures. The four rectangular apertures below 
the vault introduce the gases from the condenser. 

When a retort, for instance, that at the left of the figure, is dis- 
tilled off, the register and gas conducting channel belonging to 
this retort are closed. The retort is then lifted out, placed upon 
an iron wagon running upon a track, and taken away to cool. 
Another retort filled with wood, and made tight by a clay luting, 
is then inserted by means of a crane, and the register and gas 



MANUFACTURE OF WOOD- VINEGAR. 



225 



conducting channel are reopened. When after about one hour 
the water is expelled from the wood, and acid vapors appear, a 
copper pipe is connected with the condenser, and the joints made 
tight by a clay luting. The gases appearing in constantly in- 
creasing abundance during distillation, are now conducted under 
the second retort in order to heat it sufficiently towards the end 
of the distillation, as otherwise the charcoal will show " brands, " 
i. e. y pieces not entirely carbonized. 

A retort holding 2 cubic meters (70.63 cubic feet) of wood is 
distilled off in 8 hours. 

Horizontal retorts. Generally two wrought iron retorts are 
placed in one fire-place, for instance, 6 retorts in three fire-places 
with a common chimney, as shown in Fig. 52, one-third to two- 
thirds of their circumference being, as a rule, bricked in. In front 
and back they are closed by cast-iron disks, the front one being 

Fig. 52. 




movable so that, when an operation is finished, it can be readily 
removed, and replaced. From the back disk a pipe leads to the 
condensing apparatus. For the back disk is sometimes substi- 
tuted a conical shoulder which ends in a pipe about 8 inches in 
diameter to which the discharge pipe is secured (Fig. 54). 

Each cast-iron retort has a special fire-place, and the cylindrical, 
as well as the rectangular retorts, are bricked in only at the bot- 
tom. The brickwork is held together by several iron clamps. 
The retorts rest upon the arch above the fire-place in such a man- 
ner that they are not directly struck below by the flame but only 
surrounded by it from the side and above. It is also advisable 
to expose, not only the cylindrical space holding the retorts to the 
fire, but also the annexed conical one. The narrow pipe projects 
about one foot above the wall. 
15 



226 



VINEGAR, CIDER, AND FRUIT-WINES. 



In Figs. 53 and 54 a a a are the wrought-iron retorts, b the 
hearth, cc the flues, d the chimney. Over the somewhat conical 
neck of the retort is pushed an elbow pipe e which dips into the 
receiver F. The latter is a cast-iron pipe 1 to 2 'feet in diameter 

Fig. 53. 




(according to the number of the retorts) and extending the 
entire length of the oven. For the neck of each retort it carries 
a tubnlure 5} to 7| inches long. The object of the receiver 
is to receive the products of distillation from all the retorts 



Fig. 54. 




and at the same time to hydraulically close the elbow-pipe of 
each receiver. Hence the vapors not precipitated in the receiver 
can continue their way through g to the other condensing appa- 



MANUFACTURE OF WOOD- VINEGAR. 227 

ratus h, but cannot re-enter the retorts. This is of no slight im- 
portance, for if there were no water joint and the vapors should 
from any cause suddenly cool off, the external air might penetrate 
into the retort and the latter being filled with inflammable gases 
and vapors of a high temperature an explosion would necessarily 
follow. For making the water-joint it suffices for the elbow- 
pipes to dip f to 1 inch into the fluid in the receiver. But as the 
fluid constantly increases provision must be made for its discharge 
through a pipe, placed below or on the side, into a collecting vessel 
located in another apartment. The charcoal is at the end of the 
operation raked into sheet-iron boxes or square pits sunk in the 
floor and lined with fire brick ; both chests and pits are fitted 
with close fitting covers, since if air is not excluded the charcoal 
from its power of condensing gases in its pores, becomes so much 
heated as to take fire spontaneously. By shutting the charcoal 
in, the absorption is so far retarded as to keep the heat below the 
point of ignition. 

In many factories the charcoal is abstracted from the carbon- 
izing cylinders by means of the following apparatus : An iron 
diaphragm about the size of the interior of the retort is placed 
near the mouth of the latter, having a chain attached to it which 
runs through the whole length of the carbouizer. The workman 
by seizing this chain with a suitable instrument draws out nearly 
the whole of the charcoal at once, and with less risk of breaking 
it than when rakes are employed. 

Condensers. ^Yood ? as will be shown later on, yields more 
than half its weight of condensable fluids and among them some 
with a low boiling point. The necessity for good condensation is, 
therefore, evident, and the more so as the quantity of non-con- 
densable gaseous bodies is very large and with incomplete cool- 
ing would carry away a considerable portion of valuable bodies. 
Kestner's apparatus, Fig. 55, answers all demands. In a long, nar- 
row trough of wrought-iron or wood lies a series of straight, wide 
copper pipes, with a gradually decreasing diameter. The pipes 
are slightly inclined, so that the fluid running in at the highest 
point flows out at the lowest. Outside the trough the pipes are 
connected by movable elbow-joints. One end of each pipe is 
firmly fixed to the wall of the trough, while the other, to permit 



228 



VINEGAR, CIDER, AND FRUIT-WINES. 



free expansion, sits loosely in a slightly conical socket. The 
lower end of the last pipe divides into two branches, one of 
them leading downward and dipping into the receiver, while the 
other, as a rule, conducts the gases directly under the fire-place. 
There should be but a small space between the collecting pipe , 



Fig. 55. 




which conducts the vapors to the condenser, and the first conden- 
sing pipe, as otherwise obstructions might readily be formed by 
the deposit of tar dried by the hot vapors. A constant stream of 
water is conducted through 6, along the bottom of the trough, 
the heated water running off at c. 

The development of gas from the wood being very irregular 
and by no means in the proportion desirable for the heating of 
the retorts, it is preferable to collect it in a gasometer and distrib- 
ute it from there as may be necessary, instead of conducting it 
directly into the fire. But little gas is developed in the beginning 
of the operation, and much towards the end, while the reverse 
proportion is desirable. 

In case condensation is not very complete, the pipe leading to 
the hearth or gasometer is more or less attacked by acetic acid 
precipitated in it by the access of air. To prevent this evil it is 
advisable to place on the pipe small receptacles provided with 
cocks for the collection and discharge of any fluid deposited. 
These receptacles may also be filled with quick lime, which at 
least fixes the acetic acid, thus rendering it harmless for the pipe. 
The lime is from time to time extracted with water to regain the 
soluble calcium acetate. 

To further cool off the current of gas and render the vapors of 
acetic acid carried along with it harmless for the pipe, Vincent 



MANUFACTURE OF WOOD-VINEGAR. 229 

uses a cylindrical copper receptacle, d, Fig. 55, provided with a 
false bottom, upon which is placed a layer of crystallized soda 
from 2J to 2J feet deep. The vapors of water and acetic acid 
dissolve the soda, and the temperature thereby being lowered, a 
further portion of the volatile bodies, especially wood spirit, is 
precipitated. By distilling the fluid thus obtained, the wood spirit 
is regained, and the residue in the still used for the preparation 
of sodium acetate. 

For a condenser for four retorts of a capacity of 4 cubic me- 
tres (141.26 cubic feet) each, Gillot gives the following approved 
dimensions, provided the period of distillation is 72 hours : The 
diameter of the pipe at its entrance into the water trough is 15| 
inches, and at its exit 5f inches ; its total length is 164 to 180 
feet, this length being divided between 6 straight pieces and their 
elbow-joints. The vat is 26 J feet long with a depth of 5J feet. 

The arrangements suitable for the carbonization of wood having 
been described in the preceding pages, the most important products 
will now be more closoly considered. Before doing this a few re- 
marks as to the most suitable varieties of wood, and their con- 
stitution, may be acceptable. 

Oak, beech, hornbeam, ash, and birch give the largest yield of 
wood vinegar, less being obtained from the conifers, poplar, 
willow, and aspen. On the other hand, the conifers as well as 
the bark of birch yield considerable quantities of volatile oils. 

Woods about 20 years old seem to be especially suitable for the 
purpose of distillation. The trees should be felled in the winter, 
and the wood allowed to lie for six months and not over two years. 
It should be protected from rain and snow. To facilitate drying, 
it is best to free the wood from the bark, this being of special 
importance in regard to birch, the bark of which yields about 
40 per cent, of tar and empyreumatic oil, and the wood only 2 
per cent., hence the removal of the bark essentially facilitates the 
purification of the wood-vinegar. The removal of the bark is 
best effected by the introduction of steam of about one atmospheric 
pressure into a wooden vat covered with felt, and provided with 
a perforated false bottom, upon which the pieces of wood rest. 
After allowing the steam to act for about three hours, the bark can 
be readily detached. By drying the air-dry wood in the semi- 



230 VINEGAR, CIDER, AND FRUIT-WINES. 

cylindrical space above the retorts (Fig. 54) the content of water 
can be reduced to 10 per cent., and consequently less water has 
later on to be removed by evaporation ; besides, the distilling 
time is shortened, and a larger yield of wood-vinegar obtained. 

Charcoal. 

The substance called charcoal is not pure carbon; it containing, 
besides this element, hydrogen, oxygen (together with traces of 
nitrogen), and ash. The composition of charcoal, and conse- 
quently its properties, vary very much according to the degree 
of temperature to which the retort has been exposed, the duration 
of heating, and the variety of wood. 

By heating the wood in the retorts the hygroscopic water 
escapes first; then, at a temperature somewhat above 212 F., 
wood-vinegar makes its appearance and gradually increases in 
strength until its maximum strength is reached at 424 F. ; it 
then again becomes weaker. Next the formation of tar begins, 
and inflammable gases now make their appearance. If the opera- 
tion be continued to the end, the products are : .black charcoal, 
wood-vinegar, tar, and gases. If distillation is, however, inter- 
rupted when the greater portion of the wood-vinegar is separated 
and the formation of tar would commence, charbon roux or torrified 
charcoal, i. e., a product containing the greater portion of the 
constituents of the tar and the gases, remains. Experience has 
shown that torrified charcoal is as well adapted for use in the 
blast-furnace as black charcoal. The yield is about forty per 
cent, of the wood used, and being firmer and harder than black 
charcoal it is better adapted for transport. 

To a product intermediate between wood and torrified charcoal 
the name red-wood (roasted wood, bois roux) has been given. It 
is brown, can be worked like wood, is but slightly hygroscopic, 
highly inflammable, and has nearly double the heating power of 
wood. Its average composition is : carbon 52.6 per cent., hy- 
drogen 5.8, oxygen (together with nitrogen) 36.6, ash 0.4, water 
(moisture or constitutional) 4.5. 

For technical purposes charcoals obtained at a temperature of 
above 51 8 F. are only available, those obtained at a lower tempera- 
ture containing the so-called brands with a content of carbon of, 



MANUFACTURE OF WOOD-VINEGAR. 231 

at the utmost, 68 per cent., of hydrogen about 5 per cent., and 
of oxygen more than 26 per cent. 

With a distilling temperature of 464 F. there remains, of 100 
parts of wood dried at 302 F., a residue of 50.8 parts of brands, 
and with a distilling temperature of 518 F. 37 parts. 

With a temperature above 644 F. the result is black coal, the 
quantity and composition of which vary according to the tempera- 
ture. Between 644 F. and 810 F. remains 31.5 to 19 per cent, 
of charcoal with a composition of from 75 to 81.6 per cent, of 
carbon, 4.4 to 2 of hydrogen, and 20 to 15 of oxygen, and 0.5 to 
1.1 of ash. 

At still higher temperatures the quantity of charcoal decreases 
but little ; it amounts, for instance, at the melting point of bar- 
iron, to 17.3 per cent., and at that of platinum, to 15. per cent. 
The content of carbon, however, constantly increases until at the 
last-mentioned temperature it reaches 96.5 per cent. 

Violette further confirmed the fact long known that the degree 
of carbonization exerts a great influence upon the result, slow 
carbonization yielding far more charcoal, than quick. 

The variety of wood also exerts an influence upon the yield of 
charcoal. At 572 F. there were, for instance, obtained from 



Oak . 
Fir . 





. 46 per cent. 
. 40.7 " 


Aspen 
Beech, alder, 
Ash . 


birch .... 


. 34.9 " 
. 34.4 " 
. 33.3 " 


Linden 




. 31.8 " 



Later on Violette found that the elementary composition of 
these charcoals varied. There are contained, for instance, in char- 
coal from 

Carbon. Hydrogen. Oxygen Ash. 

(and nitrogen). 

Oak .... 67.4 4.1 28.5 0.2 

Aspen .... 68.2 5.5 25.7 0.6 

Birch .... 71.1 4.5 23.5 0.7 

Ash .... 70.4 4.5 24.4 0.7 

These figures are, however, only correct for charcoal kept air- 
tight after its preparation and immediately analyzed. Ordinary 
charcoal contains at least 5 per cent, of hygroscopic water. 



232 VINEGAR, CIDER, AND FRUIT-WINES. 

The specific gravity of charcoal depends on the carbonizing 
temperature. The specific gravity of charcoal from bird-cherry 
carbonized at 590 F. is 1.42, at 810 F. 1.7.1, at 1873 F. 1.84, 
at 2732 F. 1.87, and at the fusing point of platinum 2.0. 

The power of charcoal of conducting heat and electricity also 
increases to a remarkable extent with the increase in the carboni- 
zing temperature. 

The inflammability of charcoal is the greater the lower the 
temperature at which it was prepared. 

Charcoal possesses the property of absorbing gases and of 
taking up liquid and solid bodies from fluids, for instance, fusel 
oil, coloring substances, and alkaloids. Lead salts, for instance, 
lead acetate and nitrate, are decomposed on boiling with charcoal, 
the latter absorbing the lead oxide and liberating a corresponding 
quantity of acid. 

Charcoal also absorbs aqueous vapor from the air, and the 
more the lower the temperature at which it was formed ; the 
quantity varies from 4 to 20 per cent. Hence the charcoal ex- 
posed to the air contains only about f of its weight of carbon. 

Wood- Vinegar. 

After standing for several days in the previously-mentioned 
reservoir, the greater portions of the wood-vinegar and tar sepa- 
rate and form two layers, less often three. In the latter case the 
upper layer, which amounts to but little and may be entirely 
wanting, consists of specifically light volatile oils holding tar and 
acetic acid in solution. The second layer forms the principal 
mass and is the actual wood-vinegar. The lowest layer is tar, 
rich in specifically heavy volatile oils, especially phenol (creasote), 
containing, however, also acetic acid ; it is of a yellow-brown to 
black color, of a syrupy consistency, and specific gravity 1.07 to 

The layers are drawn off separately by means of stop-cocks 
placed at different heights on the reservoir. 

Wood-vinegar is a strongly acid fluid, generally perfectly clear, 
of a brown-yellow to red-brown color, and a strong odor (par- 



MANUFACTURE OF WOOD-VINEGAR. 233 

tially of smoke). Its specific gravity varies between 1.018 and 
1.03. When mixed with water it frequently becomes turbid. 

Wood-vinegar is a mixture of very dissimilar bodies. Besides 
its principal constituent, acetic acid, it contains several other acids 
belonging to the series of fatty acids with the general formula 
CnH 2 nO 2 ; further wood-spirit, acetone (see below), metacetone 

C 6 H 10 O, methyl acetate C J?f?lo, aldehyde, dimethyl acetal 

^2 X1 S ) 

) Of^TT 
C 2 H 4 > oQjj 3 ? furfurol, allyl alcohol C 3 H G O, small quantities of 

ammonia and of methylamine CH 3 ,H 2 !N", and finally plenols and 
guaiacols ; besides empyreumatic resins. 

To carbolic acid, one of the plenols, is due the property of 
wood-vinegar to preserve meat and other organic substances. 

On mixing wood-vinegar with soda-lye it becomes turbid, but 
on a further addition of alkali soon clarifies again and acquires a 
dark brown color, a brown body being separated. On mixing it 
with 5 to 10 per cent, by volume of concentrated sulphuric acid 
it becomes turbid and after 24 hours the greater portion of the 
tar separates in fine drops. Potassium bichromate colors wood- 
vinegar brown, and nitrate of silver is reduced at an ordinary 
temperature, a silver mirror being produced (this reduction is due 
to the content of aldehyde and creasote). 

In the distillation the more volatile bodies, of course, pass over 
first; they form a yellowish fluid which contains wood-spirit, 
acetone, etc. Then follows a turbid slightly acid water of a 
yellowish color ; it gradually becomes richer in acid, but remains 
yellowish to the end. The wood-vinegar boiling in the retort 
constantly becomes darker, and finally a clear dark brown fluid of 
a syrupy consistency and of an acid, and at the same time bitter, 
taste remains. 

In order to understand what follows it will be necessary to give 
the more important properties of the most valuable constituents 
wood-spirit and acetone occurring, besides acetic acid, in crude 
wood- vinegar. 



234 VINEGAR, CIDER, AND FRUIT-WINES. 

Wood-Spirit (Methyl Alcohol), CH 4 O. 

Wood-spirit is a colorless, very mobile liquid, of specific gravity 
0.798 when chemically pure, and with a boiling point varying 
between 150 and 160 F. The specific gravity of its vapor is 
1.12. It is soluble in all proportions in water, ether, and alcohol 
and is a solvent for resins and gums, especially when it contains 
a small proportion of acetone. With calcium chloride and with 
anhydrous barium it combines with cry stall! zable bodies, which 
are, however, immediately decomposed by water. Potassium and 
sodium dissolve in wood-spirit with the evolution of hydrogen. 
On cooling the compounds CH 3 ,OK, or CH 3 ,OXa crystallize 
out which are decomposed by water, wood-spirit and caustic alkali 
being formed. 

Pure wood-spirit does not become turbid on being mixed with 
water ; in the crude article turbidity is however caused by the 
presence of various hydrocarbons. 

Wood-spirit is chiefly used for the preparation of methyl iodide 
and methyl nitrate, both these combinations being employed in 
the fabrication of aniline colors. It is further used for the 
manufacture of varnishes, for laboratory lamps, etc., and, in 
certain cases, in medicine. 

Acetone or Dimethyl Kctone (C 3 H 6 O). 

Acetone is formed when the vapor of acetic acid is passed 
through a red-hot tube, and further by the destructive distillation 
of sugar, tartaric, lactic and citric acids, etc. The best method, 
however, to obtain it in large quantities will be given later on in 
describing the acetates (see barium acetate). 

Acetone is a very mobile, colorless liquid, boiling at 132.8 F., 
and having a peculiarly strong but pleasant odor; its specific 
gravity is 0.814. It burns with a brilliant flame and is soluble 
in all proportions in water, alcohol, and ether; it is a solvent for 
fats, resins, camphor, and gun-cotton, and yields crystallizable 
combinations with the hyposulphites ; it does not, however, com- 
bine with calcium chloride. The combinations with the alkaline 
hyposulphites, for instance sodium hyposulphite, are insoluble in 



MANUFACTURE OF WOOD-VINEGAR. 235 

the excess of the saturated solutions of hyposulphites, but soluble 
in water and boiling alcohol. By boiling such a combination 
with an alkaline carbonate, for instance, soda, it is decomposed. 
If acetone is left standing over quicklime for some time, and 
afterwards distilled, mesityle oxide C 6 H 10 O and phorone C 9 H 14 O 
are formed ; the former is a colorless fluid smelling like pepper- 
mint and boiling at 262 F., and the latter a crystallizable body 
melting at 82.4 F. and boiling at 385 F. By heating acetone 
with a little iodine and then adding alkaline solution until dis- 
coloration takes place a lemon-color, crystalline precipitate of 
iodoform soon forms. Methyl alcohol not showing this behavior, 
this furnishes a means of recognizing a content of acetone in wood- 
spirit. 

Determination of the Strength of Wood- Vinegar. 

C. Mohr gives the following method : Weigh off 10 grammes 
of wood-vinegar, heat in a beaker with about 3 grammes of pure 
barium carbonate until effervescence ceases, and filter. The solu- 
tion of barium acetate is strongly colored, but the carbonate 
remaining undissolved, very little. The residue after washing is 
dried and weighed and the quantity of acetic acid present calcu- 
lated ; each gramme of dissolved carbonate corresponding to 0.609 
gramme of acetic anhydride or 10 grammes of wood- vinegar con- 
tain 6.09 per cent. 

The quantity of undissolved carbonate can, however, be deter- 
mined in a more simple manner by titration with normal nitric acid. 
The latter is prepared by diluting commercial, pure, colorless, 
nitric acid until an equal volume of it exactly saturates normal 
sodium. Bring, for instance, 5 cubic centimetres of the commer- 
cial acid into a beaker, add a few drops of litmus tincture, and 
then by means of a burette normal soda lye until the color just 
turns blue. If, for instance, 4 cubic centimetres have been 
consumed, the 5 cubic centimetres of acid must be diluted to 40 
cubic centimetres or 125 cubic centimetres to 1 liter. 

The undissolved residue of barium carbonate together with the 
filter is now brought into a porcelain dish or beaker and a meas- 
ured volume, for instance 20 cubic centimetres, together with 



236 VINEGAR, CIDER, AND FRUIT-WINES. 

some litmus tincture, added ; the whole is then heated until the 
precipitate is dissolved and effervescence has ceased, but the solu- 
tion retains a slight red coloration. Now add drop by drop nor- 
mal sodium until the color turns blue. If, for instance, 3 cubic 
centimetres of normal sodium have been used, 20 3 = 17 cubic 
centimeters of normal nitric acid have been required for the solu- 
tion of the barium carbonate. Since 1 equivalent of barium car- 
bonate saturates 1 liter of normal nitric acid, or 98.5 grammes 
of the former 1000 cubic centimetres of the latter, each cubic cen- 
timetre of normal nitric acid consumed indicates 0.0985 gramme 
of barium carbonate ; hence in our example 1.674 gramme of car- 
bonate has not been dissolved by the acid ; there was therefore 
dissolved 3 1.674 = 1.326 gramme. And finally, as, according 
to the above, each gramme of barium carbonate indicates 6.09 
per cent, of acetic anhydride, this wood-vinegar contains 1.326. 
6.09 =* 8 per cent. 

L. Kieffer's method is based upon the following : Dissolve 
sulphate of copper in water, and after taking a small portion 
(about 3-l-g-) of it away, gradually add to the remainder ammonia 
until the pale green precipitate at first formed is redissolved ; 
then add the retained portion of the solution, and, after shaking 
and corking the flask, allow it to stand for a few hours. The 
dark blue fluid is only fit for use when the ammonia is thoroughly 
saturated with oxide of copper, i. e., when some of the precipitate 
remains undissolved. The solution is now filtered and standard- 
ized to normal nitric acid. 

By gradually adding this solution to an acid, for instance nor- 
mal nitric acid, the oxide of copper as well as the ammonia is 
fixed by the acid and two soluble salts are formed, in this case 
nitrate of copper and of ammonia. If finally the acid is saturated 
and a drop of the blue solution be added, a pale blue precipitate 
is formed, because the ammonia contained in the drop combines 
with an equivalent quantity of nitric acid in the nitrate of copper 
so that not only the oxide of copper dissolved in the drop is pre- 
cipitated (as hydrate), but also the quantity combined with the 
nitric acid. 

Thus take, for instance, 5 cubic centimetres of normal nitric 
acid and add the blue solution drop by drop with shaking from a 



MANUFACTURE OF WOOD-VINEGAR. 237 

burette. If up to the appearance of the precipitate 3.5 cubic cen- 
timetres have been used, 3.5 cubic centimetres of the copper solu- 
tion must be diluted to 5 cubic centimetres or 700 cubic centi- 
metres to 1 liter. This forms the ammoniacal copper solution 
standardized to normal nitric acid. 

To determine the strength of the wood-vinegar with this fluid, 
dilute 10 grammes - of it with water, and add, with constant agita- 
tion, copper solution until turbidity appears. The copper solution 
being standardized to normal nitric acid and the latter to normal 
sodium, the quantity of copper solution consumed is evidently just 
as large as the quantity of normal sodium would have been if 
used for titration. 

Working up the Wood- Vinegar. 

Only a small quantity of wood-vinegar is used for antiseptic 
purposes and in medicine, the greater portion being manufactured 
into wood-spirit, acetone, and acetic acid, as well as into acetates. 

There are two methods by which this can be effected. By the 
first the acetic acid of the wood vinegar is directly converted into 
acetate by saturating with hydrate of lime (slaked lime) and the 
wood-spirit distilled off. This can be effected in a cast-iron still, 
distillation being continued as long as a fluid specifically lighter 
than water passes over. The distillate is crude wood-spirit, and 
the residue is the still impure calcium acetate. 

By the second method, which is in general use, the more vola- 
tile portion (about one-tenth) of the crude wood-vinegar is dis- 
tilled off in order to obtain wood-spirit as the distillate. 
This has to be effected in a copper still. If the crude wood- 
vinegar is not entirely clear, it is best for either method to first 
pass it through a sand or charcoal filter. 

By the second method the wood-vinegar is subjected to distil- 
lation in a copper still of about 106 cubic feet capacity, Fig. 56, 
over a free fire, or less often by means of steam. What passes 
over first contains, besides water, wood-spirit, methyl acetate, ace- 
tone, and acetic acid. The vapors are, however, not allowed to 
completely condense at once but are rectified on the way by being 
conducted, as shown in the figure, through two or three rectifying 
vessels arranged in the same manner as in Pistorius's alcohol 



238 



VINEGAR, CIDER, AND FRUIT-WINES, 



still. Fig. 57 shows the arrangement of the rectifying vessels. 
The stop-cock introduces a certain quantity of water which passes 

Fig. 56. 




Fig. 57. 



from the upper to the middle basin and then to the lower one 
where it runs off. By its passage through the basins the more 
condensable vapors, consequently also those of water and acetic 
acid, are condensed, so that the non-con- 
densed portion which is only condensed in 
the cooling apparatus 6, Fig. 56, possesses a 
certain strength, it generally showing a spe- 
cific gravity of 0.965. At c, Fig. 56, imme- 
diately at the end of the discharge-pipe, is 
placed a small accurate aerometer, so that 
the specific gravity of the distillate can at 
any time be read off. 

Distillation is continued until the specific 
gravity is 1, all the distillable bodies having 
then passed over. Before being brought into commerce the crude 
wood-spirit thus obtained is generally subjected to purification, 
which will be described later on. 

If distilled wood-vinegar is to be obtained, for instance, for 
the preparation of crude lead acetate, distillation is continued, 
after changing the receiver, until oily drops appear at c,this being 
an indication of portions of the tar now passing over. Firing is 
then interrupted, and after allowing the apparatus to cool off 
somewhat, the tar remaining in the still is drawn off into the vat 
(1, Fig. 56. 

The tar is then combined with the upper and lower layers of 




MANUFACTURE OF WOOD-VINEGAR. 239 

the crude product obtained by the distillation of the wood in the 
retorts, and either brought into commerce as wood tar, or further 
worked to obtain the substances occurring in it, such as illumina- 
ting oils, carbolic acid, etc., or it is used in the manufacture of 
wagon grease, lubricants, etc. 

Wood-vinegar can, however, not be entirely purified by distil- 
lation nor by passing it over freshly glowed charcoal. Although 
seven-eighths of it passes over entirely colorless, the product has 
a strong empyreumatic taste and odor, gradually turns brown in 
the air, and gives brown salts with bases. Stoltze has proposed 
several methods for the purification of the rectified acid, the most 
simple and cheapest being to add 5 pounds of finely pulverized 
pyrolusite to every 100 quarts of acid, keeping it at nearly a 
boiling heat for 6 hours, then digesting it in the same manner 
with 40 pounds of freshly glowed charcoal pulverized and sifted 
while hot, and finally distilling off to dryness in a shallow cast- 
iron still. But on account of its tediousness and the necessary 
large consumption of fuel this process, though frequently modi- 
fied, has been almost entirely abandoned. 

According to Terreil and Chateau, the wood-vinegar is purified 
by compounding it, according to its more or less dark color, with 
10 or 5 per cent, of concentrated sulphuric acid, whereby the 
greater portion of the tar separates in 24 hours. By distilling 
the decanted acid it is obtained almost colorless, but it darkens 
somewhat on exposure to the air, and by saturation with soda a 
slightly colored salt is obtained which can, however, be discol- 
ored with a small consumption of animal charcoal. 

Rothe employs a peculiar method for the purification of wood- 
vinegar. The greater portion of the tar being separated by stand- 
ing, the wood-vinegar with an addition of charcoal is rectified from 
a copper still The pale yellow watery wood-spirit is caught by 
itself, and the succeeding clear, but strongly empyreumatic, distil- 
late is pumped into a vat placed at a considerable height from which 
it runs into a purifying apparatus. The latter consists of a cylin- 
drical pipe of strong tin-plate ; it is about 26 feet high and 1J 
feet in diameter, and is filled with pieces of coke about 0.122 
cubic inch in size, which rest upon a strongly tinned iron grate 
placed about 1J feet above the bottom of the pipe. Over this 



240 VINEGAR, CIDERj 

column of coke the wood-vinegar is poured in an uninterrupted 
fine spray, while in the space between the bottom and the grate a 
slow current of air heated to 104 F. is constantly blown in 
through a nozzle. The empyreumatic oils mixed with the wood- 
vinegar are oxidized by the oxygen of the warm air, and, in con- 
sequence, the temperature in the interior of the column of coke rises 
to 122 F., and more. (The pipe is protected from cooling oif by 
a thick layer of felt.) The products of the oxidation of the 
empyreumatic oils are partially of a resinous nature and adhere 
to the coke, and partially volatile. The acetic acid running oif 
through an S -shaped pipe on the bottom of the pipe is clear, of a 
pure acid taste and suitable for the preparation of all the acetates 
as well as of acetic acid. The very slight empyreumatic odor 
completely disappears by forcing the product through a pipe filled 
with pieces of animal charcoal freed from lime. The vinegar thus 
obtained is used for the table. Though a quantity of acetic acid 
is carried off in the form of vapor by the warm dry current of 
air, this loss can be prevented by passing the air through another 
pipe filled with calcined soda or lime. 

For obtaining acetic acid for technical purposes, for instance, 
for the preparation of aniline, acetate of lead, white lead, verdi- 
gris, etc., where a slight empyreumatic odor and taste are of no 
consequence, it is best to prepare calcium acetate and to decom- 
pose the latter with crude hydrochloric acid. 

By saturating crude wood-vinegar with slaked lime a dark- 
brown turbid solution is obtained, and much tar is separated, 
especially with the use of an excess of lime. By evaporating the 
filtered solution dark-brown rust-like flakes are separated and a 
nearly black non-crystalline salt of a strong odor remains behind 
which cannot be freed of its color and odor even by re-dissolving 
it several times. Purification succeeds better with the use of 
calcined soda for saturating the crude wood-vinegar, because the 
sodium salt crystallizes readily and the greater portion of the im- 
purities remains in the mother-lye. But even here it is not pos- 
sible to obtain the salt pure by frequently repeated re-crystalliza- 
tion. The calcium salt as well as the sodium salt can, however, 
be obtained entirely colorless by boiling the solution with animal 
charcoal, though it will not be completely freed from odor. 



MANUFACTURE OF WOOD-VINEGAR. 241 

By saturating, however, at an ordinary temperature distilled 
wood-vinegar with slaked lime, the filtered clear yellowish solu- 
tion becomes turbid after standing for some time or by heating, 
and a yellow-brown substance is separated by evaporation ; if the 
salt solution is then sufficiently concentrated, a quite strongly col- 
ored salt is again obtained. 

By slightly acidulating the solution of the calcium salt during 
evaporation with hydrochloric acid, a small quantity of a yellow- 
brown substance is separated, the previously strongly-colored 
fluid becoming pale yellow ; by evaporating to dryness a calcium 
salt of a yellowish -gray color is obtained. By slightly roasting 
this salt and then distilling with hydrochloric acid, acetic acid of 8 
B. = 1 .06 specific gravity, i. e., with about 48 per cent, of acetic 
anhydride, is obtained. 

Preparation of Crude Calcium Acetate. 

When all bodies lighter than water have been distilled off from 
the crude wood-vinegar, the retorts are allowed to cool off, and 
after carefully opening the stop-cock, the tarry Deposit is first 
drawn off; the wood-vinegar is then conducted into a large vat 
in which the saturation is to be effected. When the point of 
neutralization is reached, the solution is allowed to stand several 
hours for the impurities of the lime to separate on the bottom and 
the tarry substances dissolved in the wood-vinegar on the surface ; 
the latter are then removed. 

The fluid is now slightly acidulated with hydrochloric acid (at 
the utmost 4 pounds of crude hydrochloric acid to 22 imp. gallons) 
and allowed to rest, whereby a deposit consisting chiefly of phenol 
and other slightly acid substances is formed. The clear fluid is 
then drawn off and evaporated in a cast-iron boiler over a free 
fire. The tarry substances oxidized by the action of the air and 
separating on the surface are constantly removed. When the 
specific gravity (measured hot) has increased to 1.116, the separa- 
tion of calcium salt in the form of crusts begins ; these crusts are 
removed with an iron spatula. From this time on heating is 
carefully continued until the contents of the boiler are converted 
into a thick paste. The fire is then extinguished, the calcium 
16 



242 VINEGAR, CIDER, AND FRUIT-WINES. 

salt decomposing very readily at too high a temperature. As it 
is, however, impossible, on the one hand, to properly observe the 
temperature in the semi-cylindrical boiler, and, on the other, the 
complete dryness of the salt is required so that as many of the 
tarry substances as possible remain undissolved during the subse- 
quent re-dissolving, the paste is removed in small portions and 
spread out in flat cast-iron pans several of which are heated by 
one fire-place. During the drying the salt must be thoroughly 
stirred with iron shovels to prevent overheating. By careful 
treatment a salt containing 75 to 78 per cent, of pure acetate is 
obtained. 

By heating the calcium acetate in small cast-iron cylinders pro- 
vided with a good cooling apparatus crude acetone is obtained 
which can be purified by rectifying in a water-bath, shaking the 
distillate with saturated solution of sodium hyposulphite, and dis- 
tilling the separated crystalline body with soda solution and 
dephlegmated by rectifying over calcium chloride. 

Calcium acetate is readily prepared, can be sent long distances 
in a dry form from which the acetic acid can be readily separated 
by a process to be described later on. Entirely pure acetic acid, 
however, is not obtained from this salt, and it cannot be used for 
household or medicinal purposes, nor in the fabrication of valuable 
chemical products, for instance, certain aniline colors. Sodium 
salt will have to be taken for the preparation of acid to be used 
for these purposes. 

Preparation of Crude and Pure Sodium Acetate. 

a. The wood-vinegar freed from wood-spirit, acetone, etc., is 
saturated in a vat with calcined soda (sodium carbonate), which is 
gradually added, as otherwise the escaping carbonic acid causes 
strong foaming up. The tarry substances appearing on the sur- 
face are removed, and the brown fluid, after clarifying by standing, 
is drawn off into flat cast-iron pans which are heated by the fire- 
gases escaping from the carbonizing retorts. The concentration 
of the fluid and skimming off of the tarry substances are continued 
until the aerometer in the pan nearest the oven shows 27 B. = 
1.23 specific gravity. The register is then closed so that the fire- 



MANUFACTURE OF WOOD-VINEGAR. 243 

gases escape directly into the chimney, and the first pan is 
emptied into the crystallizing boxes. The latter are oblong sheet- 
iron vessels placed alongside each other and slightly inclined 
towards one of the narrow sides. The emptied pan being filled 
from the next, and the latter Avith fresh solution, the register is 
re-opened and evaporation commenced anew. 

When crystallization is finished the mother-lye is drawn off 
into a vat, and, after draining oif, the salt is freed from the still 
adhering mother-lye by means of a centrifugal. The crystals are 
then brought into an iron pan heated by steam and re-dissolved 
with just sufficient water to at once yiejd a hot solution of 28 
B., which is again brought into the crystallizing boxes. 

The crystals now obtained are larger and of a pale brown 
color, and moist with mother-lye. After draining off they are 
moistened with a saturated solution of pure acetate and separated 
from the mother-lye by means of a centrifugal. The crystals 
while in the centrifugal may be again moistened with a small 
quantity of the pure acetate solution, and are then obtained suf- 
ficiently pure to be at once distilled with sulphuric acid. The 
acid thus obtained, though not entirely pure, is much better than 
that from calcium salt. 

To obtain entirely pure sodium acetate, the pale brown salt 
obtained from the second crystallization is calcined, or, what is 
more simple and better, its hot solution filtered through animal 
charcoal. The salt is dissolved in water by means of steam, so 
that a nearly boiling solution of 15 to 16 B. is obtained, which 
is then slowly filtered through a layer of animal charcoal the size 
of a pea in an iron cylinder, which is covered with thick felt in 
order to retain the heat. When the charcoal ceases to act it is 
washed with water and the washwater used for dissolving a fresh 
quantity of salt. The charcoal is revived by drying and glowing 
in closed cast-iron pots and re-used. The aqueous solution of 
the pale brown acetate, together with 10 per cent, of its weight 
of bone-black, can also be heated for a few hours with constant 
stirring in an iron or copper boiler, and, after settling, decanted. 
The solution is treated with animal charcoal, and after crystal- 
lizing and passing through the centrifugal, yields an entirely pure 
salt, 



244 



VINEGAR, CIDER, AND FRUIT-WINES. 



According to an older process, the pale brown salt is melted in 
its water of crystallization, and then roasted in not too large 
portions and with constant stirring in another boiler heated to 
716 or 752 F., to destroy the remnants of tarry bodies. The 
sodium salt will stand this temperature without being decom- 
posed, but a few degrees above it, it will be decomposed and 
charred so that only a mixture of sodium carbonate and coal re- 
mains behind. The stirring which has to be kept up constantly 
in order to prevent the temperature from getting too high in some 
places, can be done by hand, but being laborious work it is better 
to provide the boiler with a lid through the centre of which runs 
a mechanical stirrer. When after roasting for 1 J hours the tar is 
destroyed, the fused salt is thrown by means of an iron shovel 
into water in a hemispherical iron boiler provided with a lid (Fig. 
58). The salt is thrown into the gutter a, from which it runs 
into the boiler b. The lid is necessary on account of explosions 
which are unavoidable in throwing in the hot salt. 

Fig. 58. 




By dissolving the roasted acetate in water, the carbonaceous 
portions remain undissolved ; the solution is, therefore, filtered 
through linen bags c, and the filtrate collected in the pit d. If 
necessary, the solution is further filtered through bone-black and 
then evaporated to 24 B. By disturbing the crystallization 
small crystals which are scarcely colored are obtained. This is 
effected by the use of round copper crystallizing vessels with a 
diameter of 5.72 feet, and a depth of about 10 inches (Fig. 59) 
and the use of a mechanical stirrer. When crystallization is fin- 
ished, the entire mass is brought into a copper boiler provided 
with a large number of apertures about 0.11 inch in diameter, 



MANUFACTURE OF WOOD-VINEGAR. 



245 



Fig. 59. 




through which the mother-lye drains off. The crystals are finally 
washed Avith a saturated solution of pure salt and passed through 
a centrifugal. The salt thus obtained 
is entirely pure ; but its preparation 
requires very careful and skilled work- 
men. 

b. Since the reduction in the price 
of soda the method of saturation de- 
scribed under a has been generally 
introduced. Formerly the sodium 
acetate was prepared by means of 
Glauber's salt (sodium sulphate) and 
lime. Notwithstanding its many de- 
fects, this method, which was introduced by Mollerat, is still in use 
in some factories. 

The wood-vinegar is saturated with slaked lime and the 
calcium salt decomposed with Glauber's salt ; gypsum (calcium 
sulphate) is precipitated while sodium acetate remains in solu- 
tion. Or, a mixture of Glauber's salt and lime (for 5 parts 
of crystallized Glauber's salt 1 part of burnt lime) is employed 
for saturation and constantly stirred while the wood- vinegar is 
added. 

Crude wood- vinegar can be used instead of the product freed 
from wood-spirit, the distilling off of the wood-spirit and acetone, 
together with the saturation, being executed in one operation, as 
follows : 

The crude wood-vinegar is distilled in a large copper boiler hold- 
ing about 106 cubic feet over an open fire or by means of steam. 
The vapors pass through a pipe into a similar boiler which is 
heated by the heat escaping from the first. In this boiler the 
mixture of Glauber's salt and milk of lime is kept in constant 
agitation by a stirring apparatus making about 25 revolutions 
per minute. The wood-spirit, etc., which is not fixed in the 
second boiler, passes into the condensing apparatus. 

In order to see whether the point of saturation is reached, 
samples are from time to time taken by means of a stop-cock 
on the bottom of the second boiler ; litmus paper being first col- 
ored blue and finally red. When this is the case, the flue 



246 VINEGAR, CIDER, AND FRUIT-WINES. 

under the second boiler is closed by a register, and the con- 
tents of the boiler being emptied into a large iron trough, 
the boiler is at once refilled with a new mixture of Glauber's 
salt and milk of lime, while a fresh portion of wood-vinegar 
is brought into the first boiler, etc. 

In the trough an abundant precipitate is formed from which 
the fluid is drawn off by means of several cocks placed at dif- 
ferent heights. The wash-waters serve for mixing fresh quanti- 
ties of Glauber's salt and lime. The solution of sodium acetate 
is evaporated, and further worked, as given under a. 

This method is, however, inferior to the one described under 
, because much fuel is required for the complete distilling over 
of the wood-vinegar, which is not the case in a, and further be- 
cause the substitution between Glauber's salt and calcium acetate 
is not as smooth as above supposed for the sake of simplicity/ the 
precipitate consisting not only of gypsum, but of a double salt of 
gypsum and sodium sulphate which dissolves with difficulty. 
The actual process is expressed by the equation : 

2(Xa 2 So 4 ) + (C 2 H 3 2 ) 2 Ca - 2(C 2 H 3 O 2 Xa) + 
Na,Ca(S0 4 ) 2 , 

which shows that only half of the sodium contained in the Glau- 
ber's salt is converted into acetate, the other half being lost. 
Moreover, there is a large quantity of insoluble precipitate which 
has to be thoroughly washed in order to avoid considerable 
loss ; and, finally, the solution of the acetate constantly deposits 
gypsum during evaporation, necessitating cleansing of the pans. 

The mother-lye from which the sodium acetate has crystallized 
out contains a considerable quantity of the latter. It is therefore 
again evaporated to 27 B. and on cooling yields crystals. By 
repeating this concentrating and cooling finally nothing more crys- 
tallizes out, the whole forming a crystalline mass, which, by absorp- 
tion of water from the air, becomes semi-fluid, and consists of very 
little sodium acetate mixed with the sodium salts of the other 
fatty acids previously mentioned. 

Barre, in 1869, showed that besides acetic acid the following 
acids occur in wood-vinegar : formic acid, CH 2 O 2 , propionic acid, 



MANUFACTURE OF WOOD-VINEGAR. 247 

C 3 H 6 O 2 , butyric acid, C 4 H 8 O 2 , valerianic acid, C 5 H 10 O 2 , and caproic 
acid, C 6 H ]2 O 2 . 

By decomposing the above-mentioned salt-mass with concen- 
trated sulphuric acid, a black oily layer consisting of a mixture of 
the above acids separates on the surface. They are but incom- 
pletely separated by fractional distillation, the separation, however, 
succeeding better by converting them into compound ethers and 
subjecting the mixture of these to fractional distillation. 

According to Vincent, 100 parts of syrupy mother-lye are 
mixed with 20 of 95 per cent, alcohol, and after gradually adding 
70 parts of concentrated sulphuric acid, the whole is allowed to 
cool. After some time a black layer separates on the surface, 
which is taken off, and after shaking with weak soda solution 
until it shows no acid reaction, and dephlegmating over calcium 
chloride, is carefully distilled, the distillates passing over between 
131 and 136.4 F., 165 and 170.6, 203 and 208.4, 237.2 
and 246.2, 271.4 and 276.8, and 323.6 and 329 being 
collected by themselves. By decomposing these products with 
barium-water alcohol is formed, which is removed by evaporation, 
and the barium salts of the fatty acids. The latter are crystallized, 
and then the acids separated by sulphuric acid. The first 
distillate yields formic acid, the second propionic acid, etc. 

Manner of Obtaining Wood Spirit (Methyl Alcohol). 

Crude wood spirit is a mixture of methyl alcohol with methyl 
acetate, dimethylacetal, acetone, inetacetone, aldehyde, various 
hydrocarbons, acetates of ammonium and methylamiue, and free 
acetic acid. 

These substances cannot be separated by fractional distillation 
alone, because the boiling point of some of them is nearly the 
same (methyl alcohol 152.6 F., dimethylacetal 147.2, acetone 
132.8, methyl acetate 131). The crude wood spirit is digested 
in a still with slaked lime, whereby, with the development of 
considerable heat, the free acetic acid always present combines 
with the lime ; ammonia and methylamine are also evolved, and 
the methyl acetate is gradually decomposed into calcium acetate 
and methyl alcohol. (By the action of the 




Ot 



248 VINEGAR, CIDER, AND FRUIT-WINES, 

with a boiling point above 212 F. are gradually formed from the 

acetone.) 

After several hours' digestion the mixture is distilled by means 
of steam. In Fig. 60, a represents the copper still, b an ellipsoidal 



Fig. 60. 




or egg-shaped vessel which serves as a receiver, and c the rectify- 
ing apparatus, consisting of a series of Pistorius's basins (see Fig. 
57, p. 238), into the uppermost of which a moderate current of 
water is conducted ; d is the condenser. 

The still a has a capacity of 1000 to 1200 quarts ; the steam 
pipe placed in it is 2 inches in diameter and 32 feet long. The 
vapors pass out through the wide pipe in the cover, and what is 
condensed in b runs back through a narrower pipe into a. In 
the rectifying vessel or rather dephlegmator, the rising vapors are 
forced to pass around a copper disk placed in each basin and thus 
to come in contact with the surface of the basin cooled by water. 
From this it is evident that the less volatile bodies are condensed 
in the basins and run back into b and from there into a, while 
the more volatile vapors pass through the swan-neck and are con- 
densed in d. Much, of course, depends on the quantity (and 
temperature) of the water running into the rectifying vessel. 

With a rectifying vessel consisting of seven basins, each 1.64 



MANUFACTURE OF WOOD-VINEGAR. 249 

feet in diameter, and with a correctly conducted influx of water, 
a product of 0.816 specific gravity is obtained by one operation 
from crude wood spirit of 0.965 specific gravity. 

This product can be used for many purposes, for instance in the 
preparation of varnishes. It is, however, not entirely pure, it 
being rendered turbid by water which is due to a content of the 
previously-mentioned hydrocarbons ; it further contains some 
acetone, methyl acetate, aldehyde, ammonia, methylamine, and 
is not fit for the fabrication of aniline colors. 

For further purification this rectified wood-spirit is diluted 
with water until it shows a specific gravity of 0.934 and is then 
allowed to rest a few days, when the greater portion of the hydro- 
carbons has separated as an oily layer on the top. The clear fluid 
is now again rectified with an addition of 2 to 3 per cent, of lime, 
whereby a distillate is obtained which does not become turbid 
with water but turns yellow in time. 

But neither this twice-rectified Avood-spirit is suitable for all 
purposes, for instance, not for the preparation of methyl iodide. 
To remove traces of ammonia and methylamine and to precipitate 
the last particles of tarry substances, it is again rectified after 
adding some sulphuric acid, this time, however, in a distilling 
apparatus standing in a water-bath, whereby a temperature of 
147.2 to 152.6 is sought to be maintained. One cubic metre 
(35.31 cubic feet) of wood yields 2 to 3 quarts of methyl alcohol 
which is not rendered turbid by water. 

For the purification of wood-spirit on a small scale, the above- 
mentioned property of methyl alcohol to form a solid crystalliz- 
able combination with calcium chloride can be utilized. Mix 
the wood-spirit once rectified over lime with dry powdered cal- 
cium chloride, pour oif the oily layer of foreign substances, which 
separates, after some standing, upon the surface of the solid com- 
bination formed, aud heat the solid body in a water-bath to 
212 F. It is not decomposed at this temperature, while the 
still-adhering impurities at least partially volatilize. Mix the dry 
residue with water, whereby the combination is broken np, and 
distill in a water-bath ; the distillate is quite pure methyl alcohol. 

The examination of commercial wood-spirit extends chiefly to 
the presence or absence of the previously-mentioned hydro- 



250 VINEGAR, CIDER, AND FRUIT- WINES. 

carbons, which can be readily ascertained by mixing the sample 
with water ; further to the presence of acetone, methyl acetate, 
and ordinary alcohol, the latter being sometimes found as an 
adulteration. The presence of acetone is recognized by the 
colorless crystalline precipitate formed on shaking with a satu- 
rated solution of sodium hyposulphite. The presence of methyl 
acetate is shown when, by boiling the wood-spirit with soda lye 
and subsequent distilling off, a residue remains in which acetic 
acid can be found. Ordinary alcohol can be detected by distill- 
ing the wood-spirit with double to four times its volume of con- 
centrated sulphuric acid. By the action of the latter upon the 
wood spirit dimethyl ether (CH^O is formed ; but by the action of 
the excess of sulphuric acid upon alcohol, cthene C 2 H 4 . The 
first is readily soluble in water, 1 volume of the latter dissolving 
37 volumes of the gas ; the latter, however, dissolves with diffi- 
culty, 7 volumes of water absorbing only about 1 volume of it. 
Hence, if alcohol be present in the wood-spirit, ethene will remain 
by shaking the gas mixture with its equal volume of water. By 
adding bromide ethene dibromide, C 2 H 4 Br 2 , a colorless oily liquid, 
having a sweetish smell and taste, is formed. 

Yield of Charcoal, Wood- Vinegar, and Wood-Spirit, as well as of 

'Tar. 

The statements as to the obtainable yield of products resulting 
from the distillation of wood vary very much, which is but 
natural, as the yield depends on many factors : on the variety of 
the wood, its age, even on the soil upon which it is grown, the 
time it has been stored, on the degree of dryness, the dimensions, 
the position of the retorts, the degrees of temperature, and espe- 
cially on the duration of carbonization. 

Stoltze, in 1820, published experiments, made with the greatest 
care, to show the amount and strength of the products obtained 
from the distillation of several varieties of wood. The quantity of 
each kind of wood submitted to destructive distillation was one 
pound, a quantity suitable, in the generality of cases, to form a 
precedent for the manufacturer on the large scale. The woods 
were all collected at the same time of the year (towards the end 



MANUFACTURE OF WOOD-VINEGAR. 251 

of January) and only those of nearly the same growth were 
chosen. From Stoltze's table the following figures for the most 
important varieties of wood have been calculated : 





Wood 
vinegar, 


Therein 
acetic Tar, 


Char- 


Gases, 


anhydride, 


coal, 


cubic 




pounds. 


pounds. pounds. 


pounds. 


metres. 


100 pounds of birch 


44.9 


O Q 


further 8.6 


24.4 


9.8 


" " beech 


44 


8.6 


9.5 


24.6 


10.8 


" " hornbeam 42.5 


7.6 


" 11.1 


23.9 


10 


" " oak 


43 


7.7 


9.1 


26.1 


10 


" " fir 


42.3 


4.2 


" 11.9 


26.6 


12.5 



or, 

1 cubic metre (35.31 cubic feet) = 750 pounds of birch, yields 
333 pounds of wood- vinegar of 20 per cent. = 66.6 pounds of 
acetic anhydride; further, 64 pounds of tar, 181 pounds of char- 
coal, and 73 cubic metres (2578.06 cubic feet) of gases. 

1 cubic metre (35.31 cubic feet) = 850 pounds of beech, yields 
371 pounds of wood-vinegar of 19.6 per cent. = 72.7 pounds of 
acetic anhydride, 80.7 pounds, 207.4 pounds of charcoal, and 85 
cubic metres (3001.86 cubic feet) of gases. 

1 cubic metre (35.31 cubic feet) = 950 pounds of hornbeam, 
yields 402 pounds of wood-vinegar of 18 per cent. = 72.3 pounds 
of acetic anhydride, 105 pounds of tar, 225 pounds of charcoal, 
and 94 cubic metres (3311.8 cubic feet) of gases. 

1 cubic metre (35.31 cubic feet) = 850 pounds of oak, yields 
367 pounds of wood-vinegar of 18 per cent, = 66 pounds of 
acetic anhydride, 77.8 pounds of tar, 223 pounds of charcoal, and 
86 cubic metres (3037.17 cubic feet) of gases. 

1 cubic metre (35.31 cubic feet) = 650 pounds of fir, yields 271 
pounds of wood-vinegar of 10.1 per cent. = 27.4 pounds of acetic 
anhydride, 72.6 pounds of tar, 138.5 pounds of charcoal, and 80 
cubic metres (2825.28 cubic feet) of gases. 

Gillot has confirmed Stoltze's statements in so far as he found 
that, in manufacturing on a large scale, with slow and carefully- 
conducted carbonization and a distilling period of 72 hours, 7 to 
8 per cent, of the (hard) wood of acetic anhydride can be ob- 
tained. 



252 



VINEGAR, CIDER, AND FRUIT-WINES. 



The results obtained by Assmus in manufacturing on a. large 
scale are as follows : 







Which 


Or 












Yield 


yield 


acetic 




Char- 


Crude 


Crude 


100 pounds of 


wood 
vinegar, 


calcium 
acetate, 


an- 
hvdride, 


Tar, 


coal, 


light 
oil, 


heavy 
oil, 




pounds. 


pounds. 


pounds. 


pounds. 


pounds. 


pounds. 


pounds. 


Birch 25 to 40 years old 
Birch-bark, first extract 


46 
22 


5.2 
0.6 


3.9 

0.4 


8 
30 


23.5 
18.5 


1.2 
21.6 


4.5 
3.0 


" second " 


20 


0.7 


0.5 


20 


22 


12 


4.7 


Oak 


42 


6.0 


4.5 


8.8 


27.5(?) 


0.8 


3.3 


Fir 


42 


3.2 


2.4 


10.5 


22 


1.3 


5.7 


Pine 


44.5 


3.0 


2.3 


9.5 


22.6 


0.6 


3.5 



















According to Rothe's experience, the trunk-wood of birch 
from 60 to 80 years old and grown upon a high dry soil with a 
limestone sub-soil surpasses the best red beech in the yield of 
acetic acid. He obtained from 100 pounds of this kind of wood 
dried at 140 to 158 F., with heating for 48 hours, at a final 
temperature not exceeding 750 F., 40 pounds of wood-vinegar 
of 25 per cent, acetic anhydride, further 2 or 3 per cent, of tar, 
and 30 per cent, of red charcoal suitable for the manufacture of 
powder. 

The yield of salable, though not entirely pure methyl alcohol, 
is J Ib. and at the utmost 1J Ibs. from 110 Ibs. of wood ; accord- 
ing to Vincent, 2 to 3 quarts from 35.31 cubic feet. This higher 
yield is said to be obtained by moistening the wood with soda 
solution and drying. In case this statement is correct, it would 
be advisable to saturate saw-dust with soda solution, and after 
drying distill in Halliday's apparatus.* It consists of a hori- 
zontal, cast-iron cylinder. The saw-dust, spent dye-wood, etc. 
are introduced through a hopper placed above the front end. In 
the cylinder a vertical screw or worm revolves at such a speed as 
to convey the material in the proper quantities to the cylinder 
placed in a horizontal position and heated by means of a furnace. 
Another revolving screw or worm keeps the saw-dust, etc., in- 
troduced in the retort in constant motion and at the same time 
moves it forward to the opposite end of the retort. During their 



Muspratt's Chemistry, Vol. I. p. 23. 



PREPARATION OF PURE CONCENTRATED ACETIC ACID. 253 

progress through the retort the materials are completely carbon- 
ized and all the volatile products disengaged. Two pipes branch 
off from the extremity of the retort, one of which passes down- 
wards and dips into an air-tight vessel of cast-iron or a cistern of 
water into which the carbonized substance falls ; the other is an 
ascending pipe and carries off' the volatile products of the distil- 
lation into the condenser, which consists of copper or iron pipes 
immersed in or surrounded by water. 

According to statements by Hargreaves and others, saw-dust 
from resinous woods gives as much wood-vinegar in 24 hours 
with 8 or 10 retorts 14 inches in diameter, as with 16 retorts 3 
feet in diameter. 

In another comparison of the two systems, 8 Halliday retorts 
consuming 22 tons of saw-dust weekly produce : 

Wood-vinegar of specific gravity 1.05 . . 2494 gallons. 
Tar 240 

While a ton of oak (2240 Ibs.) carbonized in large retorts 
gives : 

Wood-vinegar of specific gravity 1.03 . . 1277 pounds. 
Charcoal 600 " 

To make the comparison more satisfactory it would have been 
necessary to state the kind of gallon employed and the percentage 
of real acid in the wood- vinegar, since hydrometers and specific 
gravities give indications of very little value in this case. 



CHAPTER XXII. 

PREPARATION OF PURE CONCENTRATED ACETIC ACID. 

THE strongest vinegar which can be prepared by the process 
of fermentation contains somewhat above 13 per cent, of acetic 
acid, and it is difficult, even with the greatest care, to continu- 
ously obtain a product of this strength. The difficulties encoun- 
tered are due to the fact that the vinegar ferment is incapable of 
vigorous vegetation in a fluid containing, besides 10 per cent, of 



254 VINEGAR, CIDER, AND FRUIT-WINES. 

acetic acid, a sufficient quantity of alcohol for the further forma- 
tion of 3 per cent, of acetic acid, and it requires the greatest vigi- 
lance and utmost care as regards the maintenance of the correct 
temperature and ventilation in the factory to convert, under these 
conditions, alcohol into acetic acid. 

It has frequently been asked whether it is advisable to increase 
the content of acetic acid in vinegar prepared from alcohol, which 
contains only 7 or 8 per cent., to 12 or 14 per cent, by the addi- 
tion of concentrated acetic acid obtained from wood. This ques- 
tion may be answered in the affirmative, provided absolutely pure 
acetic acid, free from all empyreumatic substances, be used, and it 
is advisable in all cases to test the acetic acid as to a content of 
these substances as well as to the presence of sulphurous acid and 
of metals (copper, tin, etc.). 

To establish the presence of empyreumatic substances, dilute 
the concentrated acetic acid with twice or three times its volume 
of distilled water, and add a few drops of a solution of potassium 
permanganate. In the presence of empyreumatic substances or 
sulphurous acid the red coloration of the fluid disappears at once. 
The manner of detecting the presence of sulphurous acid and of 
copper and other metals has already been given on p. 211. 

Acetic acid which gives negative results with these tests may 
be considered as chemically pure, and can without hesitation be 
used for increasing the strength of vinegar prepared from alcohol ; 
in fact, the employment of the so-called vinegar essence for this 
purpose is constantly increasing. The fluid occurring in com- 
merce under this name is highly concentrated acetic acid with a 
content of acid varying between 60 and 80 per cent. By diluting 
this fluid with water so that its content of acetic acid is equal to 
that of ordinary table vinegar, a product is obtained which, as re- 
gards taste, can be scarcely distinguished from ordinary vinegar 
prepared from alcohol. Chemically there is also but little differ- 
ence, the vinegar prepared from alcohol containing a small quan- 
tity of acetic ether and of extractive substances which do not 
occur in vinegar essence obtained by distillation. 

For the preservation of fruit, cucumbers, and the so-called 
mixed pickles, and, in fact, for all purposes where only a fluid 
containing acetic acid and water is required, acetic acid obtained 



PREPARATION OF PURE CONCENTRATED ACETIC ACID. 255 

from wood can be advantageously used. For seasoning food, 
vinegar prepared from malt, beer, or wine is, however, prefer- 
able, it being more 'agreeable to the senses of taste and smell on 
account of its content of other substances besides pure dilute 
acetic acid. 

From strong vinegar acetic acid is obtained by distillation, the 
separation from the non-volatile substances being only possible 
by these means. If the acid is to be entirely pure, the vinegar 
is subjected to distillation in a copper still with a head and worm 
of silver or silver-plated, though this costly apparatus is now 
generally replaced by a head and worm of stone-ware. If abso- 
lute purity is not required, the head and worm may be of copper, 
or the head of copper and the worm of lead. Tin or tinned 
copper is less suitable, since a trace of tin which may be dis- 
solved causes opalescence in the distilled vinegar, and, besides, 
imparts to it a peculiar disagreeable odor. By using pure cop- 
per, distilling quickly and without interruption and cleaning the 
apparatus immediately after finishing the operation, some traces 
of copper will only be found in the first portion of the distillate. 
With the use of a leaden worm a content of lead can be almost 
entirely avoided by allowing the end of the worm to dip in water 
or vinegar, or by inserting in the end of the worm a perforated 
cork provided with a U-shaped tube, the latter preventing the 
access of air. The first portion of the distillate only contains 
lead ; it is removed and can be used, for instance, for acetate of 
lead. The distillate is from time to time tested with solution of 
sulphuretted hydrogen ; the distillate is free from lead when it 
no longer acquires a brown coloration. 

The distilled acid is, however, always weaker than the vinegar ; 
the boiling point of acetic acid being higher than 212 F., an acid 
rich in water will evidently at first pass over. Distillation, how- 
ever, cannot be carried on to dryness, as, on account of the foreign 
substances in the vinegar, the contents of the still would inevitably 
burn and the distillate acquire a disagreeable odor. Hence distil- 
lation must cease just at the time when the strongest acid would 
pass over. Stein has, therefore, recommended to increase the 
boiling point of the vinegar by the addition of one-third of its 
weight of rock salt. Though all the acetic acid is not obtained 



256 VINEGAR, CIDER, AND FRUIT-WINES. 

by these means, the amount is considerably larger than without 
such an addition. The rock salt remaining unchanged, the resi- 
due can be repeatedly used. Comparatively weak acetic acid 
can, however, only be obtained by this method. For a stronger 
product it is necessary to use an acetate and decompose it by a 
mineral acid. 

The cheapest way is to fix the acetic acid on lime and to distill 
the calcium acetate with crude hydrochloric acid. After neutra- 
lizing the vinegar with milk of lime and bringing the solution of 
the acetate to dryness, 100 Ibs. of the salt are dissolved in 110 to 
120 Ibs. of crude hydrochloric acid of 1.16 specific gravity and 
the whole is subjected to distillation. The acetic acid obtained 
by this method is not entirely free from hydrochloric acid, but 
can be readily purified by rectification over acetate of sodium or 
of calcium. 

Preparation of Acetic Acid from Commercial Acetates and 
from those obtained from Wood- Vinegar. - 

The most highly concentrated acetic acid, known as glacial 
acetic acid, was formerly exclusively obtained by the dry distilla- 
tion of crystallized verdigris (normal cupric acetate). By drying 
this salt at between 320 and 356 F. and heating, a mixture of 
acetone and glacial acetic acid is obtained which only requires 
rectification. The yield of acetic acid amounts to J of the verdi- 
gris used (see Acetates). This process has, however, been almost 
entirely abandoned, cheaper methods having been introduced. 

The principal acetates now used for the purpose are those of 
lead, barium, calcium, and sodium ; the latter two, being the 
cheapest, are exclusively used for the manufacture on a large scale, 
though the former are very suitable for the production on a small 
scale. 

By decomposing normal lead acetate, frequently called sugar of 
lead, with one equivalent of sulphuric acid (4.9 Ibs. of sulphuric 
acid to 1 9 Ibs. of the salt) sulphate of lead remains in the retort 
while acetic acid distills over. The sulphate of lead adheres, 
however, very tightly to the retort, and, being insoluble in water, 
it can, as a rule, not be removed without injury to the retort, 



PREPARATION OF PURE CONCENTRATED ACETIC ACID. 257 

Hence it is better to use 2 parts of sodium bisulphate and 1 part 
of crystallized lead acetate, a mixture of lead sulphate and neutral 
sodium sulphate then remaining in the retort, which can be 
softened with water and readily removed. Instead of bisulphate 
any desired quantity of Glauber's salt may be added to the lead 
acetate and the whole distilled with the above-mentioned quantity 
of sulphuric acid. An excess of the latter is to be avoided, the 
acetic acid being decomposed at a high temperature by concen- 
trated sulphuric acid. Distillation is carried on in a sand-bath. 
For very concentrated acetic acid lead acetate dephlegmated 
by gentle heating is used instead of the crystallized acetate and 
decomposed with one-third of its weight of concentrated sulphuric 
acid. 

The acetic acid is, however, not entirely pure in either case, as it 
contains a small quantity of sulphurous acid formed by the action 
of the sulphuric acid upon the acetic acid. This impurity can be 
readily removed by rectification over brown lead oxide (Pbo 2 ) or 
finely powdered peroxide of manganese (MnO 2 ), sulphate of lead 
remaining in the retort in the first case, and in the latter a mix- 
ture of manganous sulphate and hyposulphate. 

Bucholz gives the following direction which saves rectification, 
the required quantity of peroxide of manganese being at once added 
to the mixture of lead acetate and sulphuric acid : 192 parts of 
lead acetate, 24 of Glauber's salt, 6 of peroxide of manganese, 56 
of sulphuric acid, and 72 of water; the yield is 178 parts of 
entirely pure acetic acid of 1.045 specific gravity. 

By decomposing solution of lead acetate or of barium acetate 
with sulphuric acid, pure acetic acid which has, however, but 
little strength, can be prepared without distillation, as it is only 
necessary not to use an excess of the salts or of sulphuric acid. 
Completely anhydrous barium acetate should be used, the crystal- 
lized product being less suitable for the purpose as it readily loses 
its water of crystallization. For 100 parts of barium acetate, 
38.4 parts of concentrated sulphuric acid are required and for 
100 parts of normal lead acetate 25.9 parts of sulphuric acid. The 
solution of barium acetate should not be too concentrated, as other- 
wise the barium sulphate does not appear in the ordinary form of 
17 



258 VINEGAR, CIDER, AND FRUIT-WINES. 

a fine dense powder, but as a gelatinous precipitate which settles 
with difficulty and pertinaciously retains acetic acid. 

Finally, the lead acetate can also be decomposed by nitric acid, 
this method having the advantage of yielding a valuable by-pro- 
duct, lead nitrate. Christ! obtained from 100 parts of lead 
acetate and 53 of nitric acid of 1.38 specific gravity, 65 parts of 
acetic acid of 1.06 specific gravity and 80 parts of crystallized 
lead nitrate. A weaker acid, for instance of 1.04 specific gravity, 
can be obtained by dissolving the lead acetate in hot water, adding 
the above-mentioned quantity of nitric acid, and after allowing the 
greater portion of the lead nitrate to crystallize out, distilling the 
mother-lye. To see whether the acid thus obtained is free from 
nitric acid, compound a sample with a drop of very dilute solu- 
tion of indigo and boil for some time : discoloration proves the 
presence of nitric acid. 

Calcium acetate and sodium acetate form the basis for the 
preparation of acetic acid on a large scale ; the former, if the 
acid is to be used for ordinary technical purposes, where absolute 
purity is not required, as, for instance, in the fabrication of lead 
acetate, crystallized verdigris, aniline (from nitrobenzole and 
metallic iron), etc., and the latter, if the acid is to be free from 
empyreumatic odor and taste and suitable for use in the fabrica- 
tion of aniline colors, for photographical, pharmaceutical, and 
household purposes, etc. 

According to VolckePs method, for 100 pounds of dry yel- 
lowish gray calcium .acetate 90 to 95 pounds of crude hydrochlo- 
ric acid of 1.16 specific gravity are used, the acid obtained show- 
ing a specific gravity of 1.058 to 1.061. By adding to the above 
mixture 25 pounds of water distillation proceeds with greater 
ease. 95 to 100 pounds of acid of 1.050 specific gravity being ob- 
tained. In order to ascertain the required quantity of hydrochlo- 
ric acid more accurately than is possible from the above-men- 
tioned approximate statements, it is necessary to distill two small 
samples of the thoroughly mixed acetate, for instance, 100 
grammes, with 95 or 90 grammes of hydrochloric acid, and* to 
test the distillate for hydrochloric acid. This is readily effected 
by adding a few drops of dilute solution of nitrate of silver, a 
white precipitate or white turbidity indicating hydrochloric acid. 



PREPARATION OF PURE CONCENTRATED ACETIC ACID. 259 

The mixture of acetate and hydrochloric acid is not distilled at 
once, but allowed to stand 12 hours for the substances to act upon 
each other, and for the removal of the tarry bodies which sepa- 
rate on the surface. It is then brought into a copper still and heated 
over an open fire. , At first weak, and later on, stronger acid 
passes over. What remains is calcium chloride contaminated by 
tarry substances which have, however, become almost entirely 
insoluble. The thin pasty mixture is drawn off through a pipe 
on the bottom of the still, and, as a rule, thrown away. By evap- 
orating it, however, to dryness and roasting it for some time with 
access of air, or dissolving it in water, filtering and evaporating- 
to dryness in an iron boiler, it may serve for the preparation of 
glacial acetic acid (see below). 

Cast-iron stills can also be used and are quite durable as far as 
moistened by the acid mixture. The places exposed to the vapors 
of acetic acid are, however, quickly attacked, and it is, therefore, 
recommended to provide the upper portion of the still with a 
lining of sheet-copper. 

The acid thus obtained has a strong empyreumatic odor, is not 
entirely colorless, and sometimes contains traces of hydrochloric 
acid. By rectifying it over 1 to. 1 J per cent, of potassium bi- 
chromate the odor, coloration, and content of hydrochloric acid 
disappear, but a slight empyreumatic taste remains. 

When, however, the empyreumatic odor is not objectionable 
and only the hydrochloric acid is to be removed, the latter object 
can be attained at less cost by rectification over some calcium 
acetate or over burnt lime. A test on a small scale is also made 
in this case to ascertain the required quantity of salt or lime. 
Or the acid is titrated with solution of nitrate of silver and the 
quantity of lime or calcium acetate found by calculation added. 
The process with the use of decinormal solution of nitrate of 
silver, i. e., such as contains in 1 liter 17 grammes of crystallized 
nitrate of silver, is as follows : Mix 100 cubic centimetres of the 
acetic acid in a beaker or porcelain dish with a drop of saturated 
solution of bichromate, and add from a burette, with constant 
stirring with a glass rod, drop by drop of the decinormal solution 
of nitrate of silver until the white precipitate just commences to 
acquire a red coloration. Now read off and multiply the nura- 



260 



VINEGAR, CIDER, AND FRUIT- WINES. 



her of cubic centimetres of nitrate of silver solution consumed 
by 0.028, or, still better, as the lime is seldom pure, by 0.03. 
The product gives the quantity of lime in grammes required for 
1 liter of acetic acid. If calcium aetate is to be used, multiply 
by 0.079, or by 0.08 if the calcium acetate is not absolutely pure. 
' Rectification is executed with steam. In Fig. 61 the steam 
enters through the vertical pipe near the bottom of the still and 

Fig. 61. 




circulates in a coil ; the condensed water can be discharged through 
a pipe near the influx aperture. 

The first and last portions are not entirely clear ; they are col- 
lected by themselves, and, after mixing, allowed to clear by stand- 
ing, when the greater portion can be siphoned off. The turbid 
residue is added to a fresh mixture of acetate and hydrochloric 
acid to be subjected to distillation. 

Volckel has further found that it is not necessary to use the 
roasted gray calcium acetate, but that, with a slight modification 
of the process, the acetate prepared from crude wood-vinegar 
answers nearly as well. The crude wood-vinegar is filtered 
through charcoal and being freed from wood-spirit and acetone 
by distillation, is saturated or even slightly supersaturated in an 
iron boiler with slaked lime (litmus paper should be colored 
slightly blue). The solution is boiled for some time, and, after 
clarifying, is evaporated in an iron pan to about one-half its vol- 
ume, the resinous and sooty impurities appearing upon the surface 
being constantly removed. 



PREPARATION OF PURE CONCENTRATED ACETIC ACID. 261 

The purpose of the excess of lime is to expel the volatile basic 
bodies, ammonia and methylamine, and to decompose the volatile 
oils. The non-volatile bodies dissolved in the crude wood-vine- 
gar separate partially in saturating with lime and partially in 
boiling and evaporating. A portion of these foreign substances 
remains, however, in solution, combined with the lime so that the 
clear fluid obtained by decantation or filtration has a brown red 
color. 

It is now slightly acidulated with crude hydrochloric acid, 4 
pounds of the latter being at the utmost required for 22 impe- 
rial gallons of wood-vinegir. A considerable quantity of tarry 
substances is separated and after their removal the solution ap- 
pears less highly colored. By now evaporating to dryness and 
roasting in the previously described manner, or sharply drying 
upon heated iron plates, the salt is obtained as a dirty gray- 
brown mass. The acetic acid separated from it is, however, 
scarcely more impure than that obtained from gray salt, and by 
using somewhat more potassium bichromate, about 2 or 3 per 
cent., in the rectification, there is no difference in the quality of 
the acid. 

Reichenbach destroys the empyreumatic bodies in crude cal- 
cium acetate by distilling with an excess of concentrated sulphuric 
acid. According to his statements, a clear colorless acetic acid of 
great strength and showing no empyreumatic odor is obtained. 
The crude distillate, however, contains sulphurous acid, so that 
it has to be rectified over pyrolusite and sulphuric acid or over 
minium or potassium bichromate. 

According to Schnedermann, the wood-vinegar freed from 
wood-spirit is exposed with an excess of quicklime to the air for 
24 hours, whereby the separation of the tarry substances is claimed 
to be promoted. The clear dark-brown solution of the calcium 
salt is drawn off and after heating to boiling mixed with calcium 
chloride solution as long as the latter produces a discoloring effect. 
The now yellowish brown solution is evaporated and finally 
decomposed with sulphuric acid (or hydrochloric acid). The 
acetic acid obtained by distillation is claimed to possess only a 
slightly yellow color and to be suitable for many technical pur- 



262 VINEGAR, CIDEK, AND FRUIT-WINES. 

poses. The acid thus obtained, however, undoubtedly contains 
hydrochloric acid and has to be rectified over sodium acetate. 

Acetic acid of a pure taste suitable for household use as well as 
for technical purposes is, as previously mentioned, exclusively 
obtained from sodium acetate either by distillation or without it. 

Sodium acetate is, to be sure, completely decomposed by 1 
equivalent of sulphuric acid (36 Ibs. of acid to 100 Ibs. of crys- 
tallized salt) and, on a small scale in glass retorts, it is effected 
without difficulty, because a strong heat can finally be applied 
without injury. On a large scale, however, where the distillation 
is executed by means of steam* of two atmospheres, 1 equivalent 
of sulphuric acid is not advantageous, because the remaining solid 
neutral sodium sulphate retains much strong acetic acid. It is, 
therefore, recommended to gradually pour 2 equivalents of sul- 
phuric acid (72 Ibs. of acid to 100 Ibs. of the salt) upon the 
crystallized salt in a copper still and introduce steam after allow- 
ing the whole to rest several hours. The residue remaining in 
this process is sodium bisulphate, which remains entirely fluid at 
the distilling temperature and from which all the acetic acid can 
be expelled. A further advantage of this method is that at first 
very strong acetic acid passes over, which can be collected by 
itself and worked into glacial acetic acid (see below). Later on 
comes more dilute acid, because the water of crystallization of the 
acetate, which was at first retained by the bisulphate, also passes 
over. 

The bisulphate while still hot is poured into slightly conical 
shallow copper pans in which it congeals on cooling. It might 
thus be brought into commerce, but as the manufacturer would 
have to compete with large chemical works producing mineral 
acids, it is more advantageous to utilize it by distilling it with 
crude sodium acetate in the proportion of 3 : 2, whereby 2.5 parts 
of neutral anhydrous sodium sulphate remain behind, which, as 
previously mentioned, can be again used for the preparation of 
sodium acetate, while 2 parts of acetic acid with about 40 per 
cent, of acetic anhydride, which is pure enough for many pur- 
poses, pass over. 

* With the use of a free fire, the stills suffer very much. 



PREPARATION OF PURJE CONCENTRATED ACETIC ACID. 263 

From 100 Ibs. of crystallized sodium acetate 80 Ibs. of acetic 
acid with 55 per cent, of acetic anhydride (1.065 specific gravity) 
are obtained, or 100 Ibs. of acid with 44 per cent, of acetic 
anhydride. Asa rule, the acid is, however, not entirely pure ; 
it generally contains traces of hydrochloric acid, of sulphurous 
acid and of copper. It is, therefore, again distilled in the same 
apparatus, now provided, however, with a neck and worm of silver 
or of stoneware, some sodium acetate, or, still better, minium or 
potassium bichromate being added. In each case the hydrochloric 
acid remains behind as metallic chloride (chloride of sodium, 
lead, potassium and chromium). In the first case the first por- 
tions passing over contain some sulphurous acid and may have a 
slightly empyreumatic odor ; but the acid passing over later on is 
pure. In the second and third case the sulphurous acid is con- 
verted into sulphuric acid by the disposable oxygen of the 
minium of the bichromate and retained as sulphate, the empy- 
reumatic substances being also destroyed. 

The portion of acid of a pure taste, which passes over first in 
rectifying, being weakest, is used for household purposes ; later on 
comes a stronger acid up to 10 B. = 1.075 specific gravity. 

Although in thoroughly rectified acid no impurity can be 
established by the most sensitive reagent, for instance, potassium 
permanganate, its taste is not as pure as that of acid prepared with- 
out distillation. This imperfection can, however, be concealed by 
the addition of a small quantity of acetic ether or of alcohol 
(about 1 quart to 22 imp. gallons), which is converted into acetic 
ether. 

Mollerat's method renders, however, even this resort unneces- 
sary. According to it, pure sodium acetate obtained in small 
crystals by disturbing crystallization is decomposed with 1 equiv- 
alent of concentrated sulphuric acid (65 Ibs. of acid to 100 Ibs. 
of salt) in a large vat provided with a false bottom. The sub- 
stances being thoroughly mixed by means of a stirring apparatus, 
Fig. 62, the mixture is allowed to stand till the next day. De- 
composition is completely effected in this time at an ordinary 
temperature, the acetic acid being liberated and the greater portion 
of the neutral sodium sulphate, which dissolves but little in the 
acid, crystallized out. To prevent the perforations of the false 



264 VINEGAR, CIDER, AND FRUIT-WINES. 

bottom from being obstructed by the sulphate crystallizing out, 
sufficient pure acetic acid is previously poured into the vat to 
cover the perforated bottom. By opening the stop-cock the 
acetic acid runs off, which, however, contains a small quantity of 

Fig. 62. 




sodium sulphate in solution. The remaining sulphate is washed 
with water, and, after mixing the latter with the acid, the mixture 
is brought into stoneware-pots which are placed in cold water for 
about 8 days, whereby the greater portion of the sodium sulphate 
is crystallized out. The very small quantity remaining imparts, 
however, a laxative quality to the salt, and hence must be con- 
verted into a salt which does not possess this medicinal property. 
This is effected by mixing the acid siphoned off in a vat with 
pure calcium acetate, the required quantity of which has to be 
determined by a test on a small scale. The gypsum formed 
gradually settles to the bottom, while a corresponding quantity 
of newly-formed sodium acetate remains dissolved in the acid, 
which is, however, not injurious. 

The process may also be executed by bringing 100 pounds of 
the salt in very small crystals or finely pulverized into a stone- 
ware vessel, and adding at one time 35 or at the utmost 35.5 
pounds of concentrated sulphuric acid in such a manner that it 
lies on the bottom of the vessel below the salt. Mixing is then 
gradually effected so as to avoid heating as much as possible. 



PREPARATION OF PURE CONCENTRATED ACETIC ACID. 265 

Decomposition is complete in a few hours and the sodium sul- 
phate crystallized out on the bottom, the supernatant acetic acid 
being partially in a fluid and partially in a crystallized state. 
The acid is then siphoned off and pure calcium acetate added as 
above. The sodium sulphate is then regained and can be again 
used in the fabrication. 

The acid thus obtained need only be reduced to the strength 
desired by the consumer by diluting with water. 

Glacial Acetie Acid. 

Glacial acetic acid can be prepared by distilling 12 pounds ot 
pure anhydrous sodium acetate with 11 pounds of concentrated 
sulphuric acid. The last portion, which is frequently somewhat 
empyreumatic, is collected by itself and the portion first passed 
over rectified over sulphuric acid and pyrolusite to remove traces 
of sulphurous acid. 

A better method published by Melsens is based upon the prop- 
erty of neutral calcium acetate to absorb 1 equivalent of hydrated 
acetic acid and to form a solid acid salt which decomposes only, 
at 392 F., into hydrated acetic acid, which passes over, and into 
neutral acetate which remains behind. Hence, by decomposing 
sodium acetate with 2 equivalents of sulphuric acid and collecting 
the strong acid first passing over as long as it shows from 10 to 
8 B., it is only necessary to pour it into a copper still upon 
fused potassium acetate coarsely powdered after cooling, and after 
standing for several hours to distill over a free fire, the still 
being provided with a silver neck and a worm of the same 
material. When the temperature exceeds 248 F. all the weaker 
acid has passed over and the receiver is changed. At 392 F. 
glacial acetic acid passes over which is again rectified over fused 
potassium acetate and then exposed to a low temperature to 
freeze. 

Glacial acetic acid can also be prepared in the same manner 
from acetic acid of 1.061 specific gravity obtained by VolckePs 
method or by distilling it over anhydrous calcium chloride and 
cooling the distillate, whereby one portion crystallizes. The por- 
tion which remains liquid is poured off and again distilled over 



266 VINEGAR, CIDER, AND FRUIT-WINES. 

calcium chloride. The glacial acetic acid thus obtained contains 
considerable hydrochloric acid, but can be readily freed from this 
impurity by distilling over anhydrous sodium acetate, or, still 
better, over anhydrous potassium acetate. As by this method 
calcium chloride is obtained as a by-product (see p. 259), and 
can be freed from all organic substances by glowing with the ac- 
cess of air, the preparation of glacial acetic acid in this manner is 
just as readily executed as, though it has no advantage over, 
Melsen's process. 

Perfectly pure hydrated acetic acid dissolves oil of lemon in 
every proportion, but if one drop of water be added a portion of 
the oil immediately separates. This behavior may be utilized for 
ascertaining at what moment the strongest acid is to be collected 
at the last rectification. The pure but weaker acid obtained in 
the fabrication is used in the preparation of pure acetates. 

Below 59.9 F. glacial acetic acid forms large, colorless, trans- 
parent crystals, which above that temperature fuse to a thin color- 
less liquid, of exceedingly pungent and well-known odor; it 
raises blisters on the skin. It is miscible in all proportions with 
water, alcohol, and ether, and dissolves camphor and several 
resins. In a liquid state glacial acetic acid has a density of 1.063 
and boils at 248 F. ; its vapor is inflammable. 



CHAPTER XXIII. 

ACETATES AXD THEIR MANUFACTURE. 

A CONSIDERABLE quantity of the vinegar obtained from alcohol 
and wood (as well as the acetic acid prepared from it) is worked 
into acetates, there being, for instance, factories which use their 
entire product in the fabrication of lead acetate or sugar of lead. 
Only the more important technical acetates (combinations of 
acetic acid with metallic oxides, or, according to the view of 
modern chemists, acetic acid in which 1 molecule of hydrogen is 
replaced by a metal) will here be described. 

Acetic acid is a monobasic acid, i. c ., it contains 1 atom of 



ACETATES AND THEIR MANUFACTURE. 267 

hydrogen which can be replaced by a metal : C 2 H 4 O 2 = C 2 H 3 O 21 H. 
If this hydrogen is replaced by a univalent metal (for instance, K 
or Xa), a salt of the formula C 2 H 3 O 2 Xa or C 2 H 3 NaO 2 is formed. 
If, however, 2 atoms of hydrogen in 2 molecules of acetic acid 
be replaced by a bivalent metal, (C 2 H. s O 2 ) 2 Ba, etc., is formed, and 
finally with a trivalent metal, (Al) (C 2 H 3 O 2 ) 3 A1. 

Most of the acetates are readily soluble in water; the acetates 
of molybdenum are insoluble ; and those of argentic monoxide 
and of mercurous oxide dissolve with great difficulty. 

The preparation of the acetates is effected partially by dis- 
solving the oxides or carbonates in acetic acid, which must, how- 
ever, not be too concentrated for the barium and calcium salts, 
and partially by double decomposition, generally by means of 
the lead salt and a sulphate of another metal. 

The acetates of potassium, sodium, and ammonium show a 
slightly alkaline reaction and the readily soluble basic lead ace- 
tates .a strong alkaline one ; the remaining lead acetates react neu- 
tral or slightly acid. 

The acetates of the fixed alkalies and alkaline earths, submit- 
ted to dry distillation, yield water and acetone, while the oxide, 
and sometimes the reduced metal, remain in the distilling appa- 
ratus. The solutions of alkaline acetates become mouldy after a 
time. 

The acetic acid may be set free from its combinations by sul- 
phuric acid, and is easily recognized by its characteristic odor ; 
its salts, in common with those of organic acids, become black by 
the action of heat. 

Potassium neutral acetate, KC 2 H 3 O 2 . Acetic acid is present 
in the sap of many plants, and is generally combined with po- 
tassium, forming neutral potassium acetate. When wood is cal- 
cined the potassium acetate is decomposed, the acetic acid being 
replaced by carbonic acid. It is by this interchange that the 
carbonate of potassium found in wood ashes is formed. 

It is prepared by dissolving pure carbonate of potassium in a 
slight excess of acetic acid, evaporating and fusing. The excess 
of acid is necessary to replace that which is lost during evapora- 
tion ; without it the salt turns yellow or brown. 

Another method of obtaining it is by decomposing normal 



268 VINEGAR, CIDER, AND FRUIT- WINES. 

acetate of lead (sugar of lead) with pure carbonate or sulphate 
of potassium. To detect the presence of lead it should be 
tested with sulphuretted hydrogen, which in the presence of 
this metal produces a slightly brown precipitate. To obtain a 
pure product the decanted liquid is treated with sulphuretted 
hydrogen, and, after separating from the precipitate and adding 
a small quantity of acetic acid, is evaporated in a stone-ware 
vessel. 

Potassium acetate is readily soluble in water and ordinary 
alcohol ; it is quite soluble in absolute alcohol, but insoluble in 
ether. It is a very deliquescent salt and difficult to crystallize. 
The entirely pure salt in dilute aqueous solution should not give 
precipitates with potassium or with sulphuretted hydrogen, nor 
with barium chloride or nitrate of silver. 

At an ordinary temperature 100 parts of water dissolve 230 
parts of the salt ; a saturated solution, which boils at 336.2 F., 
contains for 100 parts of water 800 of the salt. From the alco- 
holic solution of the salt potassium carbonate is thrown down by 
a stream of carbon dioxide. 

Potassium acetate melts without decomposition at 482 F. to 
an oily liquid, and on cooling forms a crystalline, foliated mass ; 
at a red heat it is decomposed into acetone, hydrocarbons, empy- 
reumatic products, and a residue of carbon and potassium car- 
bonate. 

By the decomposition of acetate of potassium by electrolysis 
Kolbe first obtained free methyl. 

Potassium acetate, when treated with potassium hydrate in ex- 
cess, becomes converted into carbonate of potassium and marsh 
gas. When heated with arsenious acid, cacodyl (Cadet's fuming 
liquid) is produced. This reaction is so decided, and the allia- 
ceous odor evolved so strongly marked, that it forms one of the 
best tests for small quantities of acetic acid. 

Potassium acetate is an important medicine; it is employed 
as a diuretic; it is also recommended for the preservation of 
microscopic objects, .and it is occasionally used for the prepara- 
tion of pear ether (amyl acetate). 

Potassium acid acetate or potassium diacetate, KC 2 H 3 O 2 C 2 H 4 O 2 , 
is formed by evaporating a solution of the neutral salt in excess 



ACETATES AXD THEIR MANUFACTURE. 269 

of acetic acid ; it crystallizes by slow evaporation in long, flat- 
tened prisms. It is very deliquescent and decomposes at 392 F., 
giving off crystallizable acetic acid. 

Sodium acetate, NaC 2 H.,O 2 . The manner of preparing this salt 
in the fabrication of wood-vinegar has already been described. It- 
can be obtained in a manner similar to that of the potassium salt 
by dissolving carbonate of soda in acetic acid, evaporating the solu- 
tion, and setting the liquor aside to crystallize. The crystals form 
large, colorless, oblique rhombic prisms. Their composition is 
NaC 2 H 3 O 2 + 3H 2 O ; they are soluble in 3 parts of cold, in a less 
quantity of boiling water, and in 5 of alcohol. 

The taste of sodium acetate is cooling and saline. When ex- 
posed to dry air it loses its three equivalents of water, but regains 
them in a moist atmosphere. After being melted it is deliques- 
cent and takes up 7 equivalents of water ; it then becomes a liquid, 
supersaturated solution which crystallizes, with evolution of heat, 
immediately after a fragment of dry or crystallized sodium ace- 
tate is thrown into it. 

Sodium acetate is used for the preparation of acetic acid, acetic 
ether, and in medicine. Sacc recommends it for the preservation 
of animal and vegetable substances. His method consists in the 
use of powdered acetate of sodium instead of common salt. To 
keep meat fresh it is placed in a barrel with layers of acetate of 
sodium interposed between the layers of meat in the proportion 
of one-fourth of the weight of the meat. In summer the action 
of the salt is immediate ; in winter it is necessary to place the 
barrel in a heated room. As the salt abstracts the water from 
the meat, the barrel is turned about. The operation is complete 
in about 48 hours, and the meat may then be packed with its 
pickle or it may be dried in the air. If the barrels are not full, 
they may be filled up with a fresh pickle made by dissolving 1 
part of sodium acetate in 3 of water. When the pickle is drawn 
off from the meat half the salt is deposited in crystals and may 
be again used. 

Meat which has been thus treated is prepared for cooking by 
steeping for at least 12 and not more than 24 hours, according 
to the size of the piece, in tepid water, to which a small quantity 
of sal ammoniac has previously been added. This salt decom- 



"270 VINEGAR, CIDER, AND FRUIT- WINES. 

poses the acetate of sodium which remains in the meat, forming- 
sodium chloride or common salt, and ammonium acetate. The 
meat swells and resumes the color and reactions of fresh meat. 
Animals, particularly fish and poultry, may be preserved entire 
for market purposes in a pickle of sodium acetate, the only pre- 
caution necessary being the removal of the intestines. Under 
the influence of the pickle the meat loses about one-fourth of its 
weight and another quarter disappears when it is dried. The 
process is also said to be very well adapted to the preservation 
of vegetables. These generally lose thereby five-sixths of their 
weight. When needed for use, it is only necessary to soak them 
for twelve hours in water and then cook them as if entirely fresh. 

A mixture of dephlegmated sodium acetate with saltpetre ex- 
plodes with great violence on heating. According to Violette, a 
mixture of saltpetre 75 parts, sulphur 12.5, and sodium acetate 
25, acts more vigorously than gunpowder and can be granulated. 

Ammonium acetate, neutral acetate of ammonia, XH,,C,HoO . 

*/ 4/ * o 2 

This substance is obtained by neutralizing acetic acid with carbo- 
nate of ammonia, or, better, by saturating glacial acetic acid with 
dry ammonia gas. It is very difficult to obtain in the crystalline 
form on account of its aqueous solution giving off ammonia when 
evaporated, thus becoming converted into the acid salt. When 
subjected to dry distillation ammonia gas escapes first ; above 320 
F. there is formed, besides water, chiefly acetamide (C 2 H 5 1S T O), a 
white crystalline body which is also formed, besides alcohol, on 
heating acetic ether with liquid ammonia in a closed vessel to 
about 266 F. 

In medicine ammonium acetate has long been used as a 
diaphoretic. 

Calcium acetate Ca(C 2 H 3 O 2 ) 2 is prepared from burnt lime or 
calcium carbonate (marble, chalk) and dilute acetic acid. The 
preparation of the crude calcium acetate (brown salt) has been 
previously described under wood-vinegar. To obtain the pure 
salt crystallized, add to a concentrated aqueous solution several 
.times its volume of ordinary alcohol ; the salt deposits in the 
course of 24 hours. 

The crystals of the pure salt form white acicular prisms which 
effloresce in the air and are soluble in water and in alcohol ; they 



ACETATES AND THEIR MANUFACTURE. 271 

have a bitter, salty taste. They are decomposed by heat into 
acetone and calcium carbonate. A mixture of this salt and of 
potassium oxalate gives, on heating, propylene (C 3 H 6 ), while a 
mixture of carbonates remains behind. By the dry distillation 
of equal equivalents of acetate and benzoate of calcium aceto- 
phenone (C 8 H 8 O) is obtained, which by treatment with nitric acid 
is converted into nitro-acephotenone (C 8 H 7 NO 3 ). By heating the 
latter with zinc-dust and soda-lime, Emmerling and Engler claim 
to have obtained artificial indigo-blue. But the quantity of the 
latter thus obtained is always very small, and it appears to be 
very difficult to ascertain the precise condition under which the 
transformation takes place. 

With calcium chloride calcium acetate enters into a crystal- 
lizable combination ; it also dissolves some sulphate of lead. 

Barium acetate (C 2 H 3 O 2 ) 2 Ba+lJH 2 O. This substance is pre- 
pared from barium carbonate or barium sulphide and dilute acetic 
acid. Since barium carbonate, which is found native as witherite, 
and barium sulphide, which is prepared by heating barium sul- 
phate with bituminous coal, always contain iron and this iron 
passes into solution, it is separated by adding some barium water 
after the point of neutralization is reached. The solution is then 
filtered and the filtrate again neutralized with acetic acid. 

At a low temperature the solution yields colorless crystals 
derived from a rhombic prism ; they are extremely deliquescent, 
readily soluble in water, but with difficulty in ordinary alcohol 
and almost insoluble in absolute alcohol. They show a slight 
alkaline reaction, contain 3 equivalents (17.5 per cent.) of water, 
and are isomorphous with normal acetate of lead (lead sugar), to 
be described later on. By allowing the concentrated solution to 
crystallize at a somewhat higher temperature the salt absorbs, 
however, only 1 equivalent (6.5 per cent.) of water. 

By mixing a concentrated solution of the salt with sulphuric 
acid, the barium sulphate does not separate in the ordinary form 
of a fine white powder, but as a semi-transparent, gelatinous mass 
which retains acetic acid ; for this reason barium acetate is not 
suitable for obtaining strong acetic acid. 

When subjected to dry distillation barium acetate does not 
yield acetic acid, but only acetone (and very little empyreumatic 



272 VINEGAR, CIDER, AND FRUIT-WINES. 

oil) while barium carbonate remains behind. It is the best 
material for the preparation of acetone. The decomposition is 
best effected in a cast-iron vessel. With barium nitrate it gives a 
well crystallizing double salt. 

Strontium acetate. This salt is prepared in a manner similar 
to that of the preceding. The crystals obtained at 32 F. contain 
5 equivalents of water and those at 59 F. 1 equivalent. 

With strontium nitrate it gives a double salt forming beautiful 
crystals which contain 3 equivalents of water. On heating they 
first yield their water of crystallization and then detonate, a 
beautiful purple flame being formed. 

Magnesium acetate is prepared by dissolving magnesia alba or 
usta in acetic acid. It crystallizes with difficulty and is readily 
soluble in water and spirits of wine. Only a very small portion 
of the solution is decomposed by ammonia. By dry distillation 
it yields acetic acid, while magnesia remains behind. 

Aluminium acetate. The neutral salt A1 2 (C 2 H 3 O 2 ) 6 has never 
been obtained in the dry state, it being only known in solution. 
The pure combination can be prepared by introducing freshly 
precipitated and thoroughly washed aluminium hydrate into 
heated acetic acid. 

Aluminium acetate is of great importance in calico printing 
and is used as a mordant under the name of red liquw. It is 
manufactured for the use of the calico printer by adding to every 
gallon of calcium acetate liquor 2{ Ibs. of alum, agitating the 
mixture briskly and then leaving it to rest, in order that the 
calcium sulphate may settle down. The decomposition of the 
acetate is known by testing a small portion of the filtered liquid 
in a tube with a concentrated solution of alum ; if a precipitate 
of calcium sulphate falls, more alum must be added, till the acetate 
of lime is completely decomposed. The liquor is next filtered 
off, and the solution concentrated by evaporation till it acquires a 
specific gravity of 1.087 to 1.1 ; it is then allowed to repose for 
some time to deposit any sulphate of lime and finally drawn off 
for use. The quality of this liquid as a mordant is inferior on 
account of the imperfect decomposition of the lime-salt, and the 
presence of a small portion of lime still retained in the red liquor 



ACETATES AND THEIR MANUFACTURE. 273 

which impairs very much the beauty and gloss of the color given 
to the cloth. 

A better mordant is made by decomposing alum by lead acetate. 
Since lead sulphate is insoluble the decomposition of the alum 
solution is more perfect than when it is acted upon by acetate of 
lime ; nevertheless, red liquor is not a true acetate, but a mixture 
of aluminium acetate, sulphate and hydrate, with potassium sul- 
phate, as will be seen from the receipts in general use for its 
manufacture. In practice it is found advantageous to employ 
equal parts of alum and sugar of lead, or even a rather less 
quantity of the latter. The alum is dissolved in boiling water, 
and the powdered lead acetate added to the solution. About 
one-tenth of crystallized carbonate of soda, or a little carbonate 
of lime, is added to the alum to combine with the free acid. 
The three following receipts serve to indicate the proportions 
employed : 

I. Dissolve 100 pounds of alum in 50 gallons of boiling water, 
and add 10 pounds of acetate of lead in fine powder, stirring the 
mixture well at first, and likewise several times during cooling. 

II. Dissolve 100 pounds of alum in 50 gallons of boiling 
water, add slowly 10 pounds of crystallized carbonate of soda, 
and then stir in 50 pounds of acetate of lead in powder. 

III. Dissolve 100 pounds of alum in 50 gallons of boiling 
water, and add in small portions 6 pounds of crystallized carbon- 
ate of soda, and then stir in 50 pounds of acetate of lead, in 
powder, as before. 

When used by the calico printer the red liquor is thickened 
with gum or some other suitable material, and with it the design 
is impressed upon the cloth by a wood block, or by any other 
means; on subsequently submitting the goods to the drying-bath, 
acetic acid is partly volatilized, and the aluminous basic compound 
remains perfectly combined with the cloth. 

Grace Calvert states, from practical observations, that a sulpli- 
acetate of alumina is to be preferred as giving the most satisfac- 
tory results. He considers that a mordant of such a composition 
is best adapted for fixing the colors, on account of the excess of 
alumina in such a solution above those which contain, besides the 
.18 



274 VINEGAR, CIDER, AND FRUIT-WINES. 

aluminous salts, salts of the alkalies, which are inert in the uses 
for which red liquor is manufactured. 

He recommends the following formulae : 

I. Ammonia alum, 453 pounds ; lead acetate, 379 ; water, 1132. 

II. Aluminium sulphate, 383 pounds ; lead acetate, 379 ; water, 
1132. 

III. Alum, 453 pounds, and a quantity of solution of acetate of 
lime, amounting to 158 pounds. 

IV. Aluminium sulphate, 333 pounds, with the same amount of 
acetate of lime solution. 

On agitating the foregoing mixtures, decomposition takes place ; 
sulphate of lead or of lime is thrown down and a sulphacetate 
remains with an equivalent of ammonium sulphate from the am- 
monia alum. 

In 1872, Messrs. Storck & Co., of Asnieres, France, patented 
a process for the manufacture of aluminium acetate from the 
phosphate. Aluminium phosphate is converted into acid phos- 
phate by dissolving it in phosphoric acid. Soluble aluminium 
acetate and insoluble lead sulphate are thus formed. The alum- 
inium acetate is then separated by filtration, and subsequently 
treated in a manner similar to that obtained for industrial pur- 
poses by the double decomposition with aluminium sulphate. 
The phosphate of lead is either used to produce pure phosphoric 
acid by decomposing it by sulphuric acid, or sulphuretted hydro- 
gen, or an alkaline phosphate is formed thereof by treating it 
with an alkaline sulphide. It may likewise be used for the pro- 
duction of phosphorus ; in this case it is mixed with charcoal and 
subjected to distillation. 

Manganese acetate, Mn(C 2 H 3 O 2 ) 2 . This substance is prepared 
by dissolving freshly precipitated manganous carbonate (MnCO 3 ) 
in heated acetic acid, evaporating the solution and crystallizing. 
The crystals are of the rhombic prism, and occasionally in plates 
of an amethystine color; they are permanent in air, soluble in 
alcohol, and in about three times their weight of water. 

On a large scale this salt is manufactured by precipitating a 
solution of manganous sulphate* by one of lime acetate and 

* Manganous sulphate is prepared by mixing the dioxide (pyrolusite) with 
half its weight of concentrated sulphuric acid and heating in a Hessian cru- 



ACETATES AND THEIR MANUFACTURE. 275 

agitating the liquor to decompose the whole of the manganese 
salt. 

It sometimes happens that a portion of the manganese salt is 
not acted upon by the acetate of lime ; in this case a concentrated 
solution of acetate of lead is employed towards the end of the 
process to effect the complete decomposition. The mixed precip- 
itate of sulphate of lime and lead is filtered off, and the filtrate 
evaporated and crystallized. The best acetate of manganese is 
made by adding to 4 parts of manganous sulphate dissolved in 
3 parts of water, 7 parts of crystallized acetate of lead dissolved 
in 3 parts of water, agitating the solution, and drawing off the 
clear liquor for use. 

Acetate of manganese is used in dyeing and calico printing to 
give a brown color to fabrics. Its principle of action depends 
upon the further oxidation of the manganese. 

Iron acetates. Acetic acid combines with ferrous oxide (FeO) 
as well as with ferric oxide (Fe 2 O 3 ), but only the ferrous acetate 
crystallizes in small greenish white needles, very prone to oxi- 
dation ; ferric acetate is a dark, brownish red, uucrystallizable 
liquid, of powerful and astringent taste. Both salts dissolve 
freely in water, and are of importance for dyeing and calico 
printing. 

Ferrous acetate, Fe(C 2 H 3 O 2 ) 2 . For dyeing purposes this salt is 
prepared by dissolving wrought-iron turnings in wood-vinegar, 
care being had that some iron remains undissolved, as otherwise 
the salt, on exposure to the air, is gradually partly converted into 
the ferric salt. This oxidation proceeds, however, but slowly, 
the empyreumatic substances contained in the wood-vinegar ren- 
dering the conversion rather difficult ; the pure salt oxidizes with 
greater rapidity. For commercial purposes this compound is 
manufactured as follows : Into a large wooden vat or into barrels 
a quantity of iron turnings, hoops, or nails are introduced, and hot 
crude wood-vinegar, freed by distillation from wood-spirit, is poured 
upon them. During the solution of the iron much tarry matter 
separates which is skimmed off, and the solution is frequently 

cible until no more vapors escape. The residue is dissolved in water, filtered, 
and allowed to crystallize at an ordinary temperature. The solution of the 
salt when decomposed with crystallized soda gives a precipitate of manganous 
carbonate. 



276 VINEGAR, CIDER, AND FRUIT-WINES. 

agitated to free it as much as possible from the tar. After 24 
hours the solution is drawn off. The iron being entirely coated 
with tar so that it is not again attacked by the wood- vinegar, it 
is taken from the vat and the tar ignited. The iron being freed 
from the oxide formed by sifting can be again used. The solu- 
tion thus obtained shows 13 or 14 B. 

The pure salt is obtained by dissolving iron in acetic acid or by 
double decomposition from ferrous sulphate (14 parts) and lead 
acetate (19 parts); and cheaper, but less pure, from ferrous sul- 
phate and calcium acetate. 

If crude calcium acetate instead of wood- vinegar is to be used 
in the preparation of this salt, a solution of the calcium acetate 
of specific gravity 1.08 is mixed with half its weight of ferrous 
sulphate dissolved in 2J times its weight of water. On agitating 
the mixture the decomposition is rendered complete, the clear 
liquor which is siphoned off after the subsidence of the sulphate 
of lime showing 13 B. It is kept in a closed barrel in which is 
hung a bag containing a quantity of iron turnings. 

In some factories the ferrous acetate is manufactured by de- 
composing the carbonate of iron (FeCO 3 ) with lead acetate ; lead 
carbonate precipitates, and the blackish supernatant liquor is the 
acetate of iron in a very pure state. It is kept from oxidizing 
by immersing in it some bright iron filings. The lead salt 
formed repays the cost of the manufacture of the acetate. 

Solution of ferrous acetate is used as a mordant by dyers, for 
staining wood and leather and in the manufacture of ink. The 
commercial article generally shows a specific gravity of 1.10 
(12 B.). 

On account of the avidity with which ferrous acetate absorbs 
oxygen, it is of great value as a reducing agent. It is, for instance, 
used in the preparation of aniline from nitrobenzole and for 
similar reducing processes. 

Neutral ferric acetate or sesquiacetate of iron, Fe(C 2 H 3 O 2 ) 3 . 
For technical use this combination is obtained by dissolving 
wrought-irou in wood-vinegar so that it has a chance to oxidize 
in the air. For this purpose wood-vinegar is poured over iron 
turnings in a vat, and after drawing off the solution, in a few days 
the iron is for some time left to the action of the oxygen of the 



ACETATES AND THEIK MANUFACTURE. 277 

air. It quickly oxidizes and by pouring back the solution and 
several times repeating the drawing off and pouring back, a quite 
concentrated solution of a dark red brown, nearly black color is 
in a short time obtained. Heat must not be employed in the 
preparation of this salt, as in such case it readily decomposes. 

Neutral ferric acetate may be obtained in the pure state by 
decomposing a solution of lead acetate by addition of ferric sul- 
phate in slight excess. In the course of 24 hours the excess of 
ferric sulphate precipitates as a basic salt. It is also produced, 
though more slowly, by dissolving ferric hydrate or ferric car- 
bonate obtained by precipitation, in strong acetic acid. This 
method occupies more time, but affords better guarantees for the 
purity of the compound. 

By dissolving one part of nitric acid or aqua regia, precipitating 
the solution with ammonia and dissolving the washed ferric 
hydrate in 10 parts of acetic acid of 1.042 specific gravity and 
evaporating the solution at from 140 to 176 F. an amorphous 
salt soluble in water and alcohol remains, which is, however, not 
neutral, as it contains only 2 instead of 3 equivalents of acetic 
acid for 1 equivalent of ferric oxide. By dissolving this amor- 
phous salt in acetic acid and exposing the dark red solution to a 
low temperature, the neutral salt crystallizes out in hydrated, lus- 
trous, dark red laminae. 

On heating the strongly diluted solution of this salt nearly to 
the boiling point its color becomes more intense and it evolves 
a distinct odor of acetic acid without, however, producing a precipi- 
tate. The salt has nevertheless become more basic, and an addi- 
tion of any soluble sulphate or even of free sulphuric acid immedi- 
ately precipitates the whole of the iron as insoluble basic ferrous 
sulphate. By heating, however, the dilute solution of the pure 
acetate to boiling it disengages acetic acid and separates a basic 
salt, which, if boiling be continued, also loses its acid so that ferric 
hydrate remains behind. The properties of this hydrate differ, 
however, from those of ordinary ferric hydrate, it being only 
dissolved in concentrated hydrochloric acid by long-continued 
digestion or boiling and scarcely attacked by boiling concentrated 
sulphuric acid. In acetic acid or dilute nitric acid it dissolves, 
however, to a red fluid, transparent to transmitted, but opaque to 



278 VINEGAR, CIDER, AND FRUIT-WINES. 

reflected, light. By adding the slightest quantity of a sulphate or 
of concentrated nitric or hydrochloric acid, a granular precipitate 
is formed, which, however, redissolves on diluting the fluid with 
water. If a solution of ferric acetate is heated in a closed vessel 
to 212 F. for a few hours, the fluid seen by reflected light appears 
opaque and opalescent ; it lias also lost its metallic taste and no 
longer shows the other reactions of ferric salts, i. <?., addition of 
ferrocyanide produces no precipitate nor does the sulphcyanide 
augment its red color. A trace of sulphuric acid or any alkaline 
salt suffices to precipitate the whole of the iron in solution as 
ferric hydrate of red color, which is totally insoluble in all acids at 
an ordinary temperature ; dilute mineral acids do not, however, 
produce a similar precipitate. It is remarkable that this ferric 
hydrate dissolves in water to a dark red fluid which can be again 
precipitated by concentrated acids or alkaline salts (Pean de 
St. Giles). 

From the iron acetates the iron is precipitated as black ferrous 
sulphide by sulphuretted hydrogen. 

With ferric nitrate ferric acetate yields a crystallizable double 
salt, Fe (C 2 H 3 O 2 ) 2 NO 3 + 3H 2 O, the solution of which decomposes 
on boiling, nitric and acetic acids being disengaged. A similar 
combination exists between the acetate and ferric chloride. 

The acetates of iron are employed in woollen dyeing to produce 
blue with potassium ferrocyanide and ferricyanidc ; in cotton 
dyeing and printing, and in silk dyeing they are used for blacks, 
russets, etc. Ferrous acetate is used with madder, for violet ; or 
together with red liquor, for brown ; it is also used for dyeing 
hats and furs black and for blackening leather, wood, etc. Some 
dyers prefer the ferrous acetate, because, by the oxidation of the 
iron subsequently to dyeing, the colors are more resistant ; but 
greater uniformity of the ground is insured by the use of ferric 
acetate. For the preparation of ink ferrous acetate is to be pre- 
ferred. 

A mixture of ferric acetate with alcohol and acetic ether forms 
Klaproth's tincture of iron, which is used in medicine. 

Chromium acetate*. Acetic acid enters into combination with 
chromous (CrO) as well as with chromic oxide (Cr 2 O 3 ). The salts 
are not used in the industries and are only of scientific interest. 



ACETATES AND THEIR MANUFACTURE. 279 



Chromous acetate, (C 2 H 3 O 2 ) 2 Cr -f H 2 O, is prepared by mixing a 
solution of chromous chloride with sodium acetate. The salt- 
separates out in small, lustrous red crystals which are sparingly 
soluble in water and alcohol and quickly oxidize to a greater 
degree on exposure to the air, the succeeding salt being formed. 

Chromic acetate. A neutral salt is known and there are very 
likely several basic ones. The solution of the neutral salt, which 
is obtained by dissolving chromic hydrate in heated acetic acid, 
forms a red fluid, green in a reflected and red in a transmitted 
light. It is not decomposed by boiling, but by ammonia. The 
precipitate, however, redissolves, on adding ammonia in excess, to 
a violet-red fluid because the hydrate is soluble in ammonium 
acetate. Hence, a solution of the salt acidulated with acetic acid 
is not precipitated by ammonia. 

There are also known crystallized combinations of this salt 
with chromic chloride and sulphate and nitrate of chromium. 

If the solution of the neutral salt is for some time digested 
with chromic hydrate, it acquires a darker color, the acid re-action 
disappears, and on evaporating a green powder soluble in water 
remains behind. Ordway has described a purple basic salt. 

Nickel acetate forms small green crystals soluble in water, but 
not in alcohol. 

Cobalt acetate forms small red crystals, the concentrated solution 
of which turns blue on heating but again red on cooling, and can, 
therefore, be used as sympathetic ink. 

Zinc acetate, Fn(C 2 H 3 O 2 ) 2 . This salt may be prepared by 
dissolving metallic zinc, zinc oxide or zinc carbonate in acetic 
acid, or by the decomposition of zinc sulphate by acetates of lime 
or lead similar to the acetate of manganese. The acetate is 
in the first three instances simply obtained by evaporation, and 
in the latter, after agitating the mixture, filtering and evaporating 
the filtrate. The salt crystallizes in flexible, opalescent, six-sided 
tables which effloresce slightly in the air. Technically the best 
receipt is to dissolve 4 parts of the sulphate of zinc and 7 J parts 
of acetate of lead each in 3 parts of hot water, mixing the solutions, 
agitating, and after the sulphate of lead has deposited, drawing 
the clear liquid off to crystallize. 



280 VINEGAR, CIDER, AND FRUIT-WINES. 

Acetates of copper. Cuprous acetate, Cu 2 (C 2 H 3 O 2 ) 2 . This salt 
is produced by subjecting crystallized verdigris to dry distillation. 
It is a white substance crystallizing in fine needles, which are 
decomposed by water into yellow cuprous hydrate and cupric 
acetate. 

With cupric oxide acetic acid forms a normal and several basic 
salts. 

Neutral cupric acetate ; crystallized verdigris, Cu(C 2 H 3 O 2 ) 2 . The 
normal cupric acetate may be prepared by dissolving pure cupric 
oxide or cupric hydrate in pure acetic acid or by employing, instead 
of the pure oxide, copper scales whose content of metallic copper 
and of cuprous oxide is converted into cupric oxide by moistening 
with nitric acid and gentle glowing ; the cupric oxide thus obtained 
is washed to remove foreign substances. The conversion of the 
cuprous oxide into cupric oxide is especially essential when the 
acetic acid is not entirely free from hydrochloric acid, as other- 
wise cuprous chloride is formed which dissolves with difficulty. 

If copper scales cannot be obtained, hydrated basic carbonate 
of copper can be prepared by precipitating sulphate of copper 
with soda, and, after washing and pressing, dissolving in acetic 
acid. Sulphate of soda remains dissolved in the water, and this 
solution can eventually be utilized for the conversion of crude 
calcium acetate into sodium salt. Instead of soda, milk of lime 
can also be used for the decomposition of the sulphate of copper : 
a mixture of calcium sulphate and cupric hydrate is precipitated. 
By adding acetic acid the latter is redissolved while the calcium 
sulphate remains suspended. When the latter has settled the 
solution is drawn off and evaporated. The calcium sulphate is 
repeatedly washed with small portions of water, and the wash- 
waters used for dissolving fresh quantities of sulphate of copper. 

In case the sulphate of copper contains iron the latter is re- 
moved by digesting the solution for several days with basic car- 
bonate of copper. The presence of iron is recognized by the sul- 
phate not dissolving entirely in ammonia in excess, but leaving 
behind a red-brown residue (ferric hydrate). 

The neutral acetate can also be prepared by dissolving the 
basic salt, verdigris (described below), in acetic acid. The solu- 



ACETATES AND THEIR MANUFACTURE. 281 

tion is filtered and evaporated until a crystalline film is formed. 
This method is, however, expensive. 

The method by double decomposition may be recommended 
for preparing the neutral acetate on a small scale, but not for 
manufacturing purposes. Sulphate of copper (125 parts) and 
sodium acetate (136 parts) decompose each other, neutral cupric 
acetate crystallizing out while sodium sulphate remains in solution. 
The yield is, however, somewhat smaller than theoretically might 
be expected, because the sulphate of copper is not entirely insolu- 
ble in sodium sulphate solution. By this process the object is 
quickly accomplished and for this reason is decidedly to be pre- 
ferred to the following : Sulphate of copper (125 parts) and nor- 
mal lead acetate (190 parts) decompose completely only in dilute 
but not in concentrated solutions. Hence strong evaporation is 
required whereby acetic acid is lost. Further, with the use of 
lead acetate some of the newly formed lead sulphate is obtained in 
solution ; but the lead cannot be separated with sulphuretted 
hydrogen because the latter would decompose also the copper salt. 
The disadvantage of substituting calcium acetate for the lead 
acetate is that it is not crystallized and hence furnishes no ex- 
ternal criterion of purity ; in fact it always has a slightly varying 
composition. If a small excess of calcium salt has been used, the 
latter, after the calcium sulphate is filtered off and the solution 
evaporated, does not remain in the mother lye, but crystallizes 
out as double salt (see below), together with the copper salt. 
Since these acetates create difficulties, and as each of them must 
first be prepared by the manufacturer by means of acetic acid, it 
would seem more rational to directly use this acetic acid for dis- 
solving the cupric oxide, whereby no by-products of little value, 
such as sulphate of lead, calcium and sodium, are formed. 

The evaporation of the solution of cupric acetate obtained by 
any of the above methods is effected in a copper boiler over an 
open fire, or, still better, by steam. It is recommended to close 
the boiler so that the escaping vapors of water and acetic acid 
are condensed in a worm. Independently of the fact that by these 
means the escaping acetic acid is regained and can be used for 
other purposes, a great advantage is that the air of the workroom 
is thereby not contaminated by flying particles of salt. 



282 VINEGAR, CIDER, AND FRUIT-WINES. 

Crystallization is generally effected in stone-ware pots into 
which dip a number of slender wooden rods. The pots are 
placed in a warm room. Crystallization is finished in about 14 
days. The crystals turn out especially beautiful when the acid 
somewhat preponderates and the cooling of the solution is effected 
very slowly. 

The salt forms dark green* rhombic prisms of a nauseous 
metallic taste, which dissolve in 14 parts of cold and 5 parts of 
boiling water, and are also soluble in alcohol. Heated in the 
air the crystals burn with a green flame. 

Neutral cupric acetate contains in 100 parts, cupric oxide 
39.8, anhydrous acetic acid 51.1, water 9. 

On heating, the dilute solution of the neutral salt yields acetic 

O/ 

acid and deposits a basic salt ; hence the use of strongly diluted 
acetic acid or even distilled vinegar is not suitable for the prepa- 
ration of crystallized verdigris. By long-continued digestion with 
freshly glowed charcoal the dilute solution yields its entire con- 
tent of copper to the latter ; hence vinegar containing copper can 
be purified in this manner (2 or 3 per cent, of charcoal being suffi- 
cient). The crystals of normal cupric acetate, after drying in 
vacuo, lose no more water at 212 F., but give off 9 per cent, of 
their water between 230 and 284 F. By destructive distilla- 
tion cupric acetate yields strong acetic acid which contains acetone 
and is contaminated with copper. Cuprous oxide (Cu 2 O) is obtained 
111 red octahedral crystals when the neutral salt is heated with or- 
ganic substances, such as sugar, honey, starch, etc. With the 
acetates of potassium, sodium, and calcium, normal cupric acetate 
gives double salts of a vivid blue color, which form fine crystals. 
The chief use of normal cupric acetate in the arts is in making 
pigments and for resisting the blue color which the indigo would 
communicate in the indigo bath of the calico printer. In the 
latter case its mode of action depends on the readiness with which 
it parts with oxygen, whereby the indigo is oxidized before it 
can exert any action on the cloth, being itself reduced to the 

* There is also another salt of a beautiful blue color, which contains, how- 
ever, 5 equivalents of water (Wohler). It is prepared by exposing a solu- 
tion of the salt mixed with free acetic acid to a low temperature. At 95O F. 
it passes into the ordinary green salt. 



ACETATES AND THEIR MANUFACTURE. 283 

state of acetate of suboxide of copper. Crystallized verdigris is 
occasionally employed as a transparent green water color or wash 
for tinting maps. In medicine it is used for external application. 
It is poisonous like all soluble copper salts. 

Basic cupric acetates. Sesquibasic cupric acetate (Cu(C 2 H 3 O 2 ) 2 ) 2 
CuO + 6H 2 O. This compound is obtained pure by gradually 
adding ammonia to a boiling concentrated solution of the normal 
acetate until the precipitate, which is at first formed, is redis- 
solved. As the liquor cools the new salt then crystallizes out in 
beautiful blue-green scales, which at 212 F. lose 10.8 per cent, 
of their water. Their aqueous solution is decomposed by boiling, 
acetic acid being given off and the black oxide of copper pre- 
cipitated. 

Dibasic cupric acetate, Cu(C 2 H 3 O 2 ) 2 CuO 4- 6H 2 O, constitutes 
the greater part of the blue variety of verdigris. It forms beau- 
tiful, delicate, blue, crystalline needles and scales, which when 
ground form a fine blue powder. When heated to 140 F. they 
lose 23.45 per cent, of water and become transformed into a 
beautiful green, a mixture composed of the neutral and tribasic 
acetates. By repeated exhaustion with water the dibasic is re- 
solved into the insoluble tribasic salt, and a solution of the nor- 
mal and sesquibasic cupric acetates. 

Tribasic cupric acetate, Cu(C 2 H 3 O 2 ) 2 2CuO -f 3H 2 O. This 
compound is the most stable of any of the acetates of copper. It 
is prepared by boiling the aqueous solution of the neutral acetate, 
by heating it with alcohol, by digesting its aqueous solution with 
cupric hydrate, or by exhausting blue verdigris with water, as 
mentioned above. The first methods yield the salt in the form 
of a bluish powder composed of needles and scales, the last as a 
bright green powder. This salt gives off all its water at 352 
F. ; at a higher temperature it decomposes and evolves acetic 
acid. Boiling water decomposes the solid tribasic acetate into a 
brown mixture of the same salt with cupric oxide. 

Under the name of verdigris two varieties of basic cupric 
acetate are found in commerce : French verdigris which occurs 
in globular, bluish-green, crystalline masses, but also in amor- 
phous masses, and English verdigris of a pure green color and 



284 VINEGAR, CIDER, AND FRUIT-WINES. 

crystalline structure, which is, however, also manufactured in 
Germany and Sweden. 

The first variety is chiefly manufactured in the region around 
Montpellier, France. The refuse of grapes, after the extraction 
of the juice, is placed in casks until acetous fermentation takes 
place. The casks or vessels are covered with matting to protect 
them from dirt, At the end of two or three days the fermenting 
materials are removed to other vessels in order to check the pro- 
cess, to prevent putrefaction. The limit to which fermentation 
should be carried is known by introducing a test-sheet of copper 
into the mass for 24 hours ; if, on withdrawing it at the end of 
that time, it is found covered with a uniform green coating, the 
proper degree of fermentation is reached. 

Sheets of copper are prepared by hammering bars of the metal 
to the thickness of about -^ of an inch (the more compact the 
copper sheets the better), and they are then cut into pieces of 6 
or 8 inches long by 3 to 4 broad. Sometimes old ship-sheathing 
is used and cut into pieces of the required size. The sheets are 
immersed in a concentrated solution of verdigris and allowed to 
dry. When the materials are all found to be in proper condition, 
the copper sheets are laid on a horizontal wooden grating in the 
middle of a vat, on the bottom of which is placed a pan of burn- 
ing charcoal, which heats them to about 200 F. In this state 
they are put into large stoneware jars with alternate layers of the 
fermenting grape lees ; the vessels are covered with straw mats 
and left at rest. At the end of 10 to 20 days they are opened to 
ascertain if the operation is complete. If the upper layer of the 
lees appears whitish and the whole has worked favorably, the 
sheets will be covered with silky crystals of a green color. The 
sheets are then taken from the jars and placed upright in a cellar, 
one against the other. At the end of two or three days they are 
moistened with water and again placed to dry. This moistening 
with water is continued at regular intervals of a week for six or 
eight times. This treatment causes the sheets to swell and 
become incrusted with increased coatings of the copper salt, 
which are detached from the remainder of the sheets by a copper 
knife. The scraped plates are submitted to a fresh treatment till 
the whole of the copper is converted into verdigris. The salt 



ACETATES AND THEIK MANUFACTURE. 285 

scraped off is made into a consistent paste by kneading with a 
little water, and in this state is packed into leathern bags which 
are placed in the sun to dry until the mass hardens and forms 
the tough substance which constitutes the commercial article. 

In England, Germany, and Sweden copper sheets are moistened 
with a solution of verdigris in vinegar and placed in a warm 
room, or woollen cloths moistened with the above solution are 
used, which are placed alternately with the copper sheets in a 
square wooden box. 1 The woollen cloths are moistened with the 
solution every three days for 12 or 15 days when small crystals 
commence to form on the sheets. The sheets are then drawn 
every six days through water and replaced in the box, but not in 
direct contact with the woollen cloths, small disks of copper or 
small pieces of wood being placed between each cloth and sheet. 
The woollen cloths are now more thoroughly saturated than 
before, but with a weaker solution. With a temperature of from 
54 to 59 F., 6 to 8 weeks are required before the verdigris can 
be scraped off. The product is not identical with that obtained 
by the French method, it being somewhat poorer in acetic acid, 
and hence its color is not bluish-green but almost pure green. 

According to Philipps the composition of the two varieties of 
verdigris is as follows : 

English 

French crystallized 

verdigris. verdigris. 

Cupric oxide 43.5 43.25 

Anhydrous acetic acid .... 29.3 28.3 

Water . .' 25.2 28.45 

Impurities ....... 2. 

On account of having more body the globular verdigris is pre- 
ferred by painters, notwithstanding its being more expensive and 
less pure than the green article. It is frequently adulterated 
with gypsum or chalk and also with heavy spar. If efferves- 
cence is produced by pouring pure hydrochloric or nitric acid 
over the verdigris and the filtrate precipitated by sulphuric acid, 
chalk is present. If a white residue remains on digesting the 
verdigris with an equal weight of acetic acid of 1.045 specific 
gravity, gypsum or heavy spar has been added. In case this 
residue, after washing with a mixture of acetic acid and spirits of 



286 VINEGAR, CIDER, AND FRUIT-WINES. 

wine until a sample of the filtrate is no longer colored blue by 
ammonia, and then treating with distilled water, yields a fluid 
which produces precipitates with barium chloride as well as with 
ammonium oxalate, it consists of or contains gypsum; in the 
other case heavy spar is present. 

Considerable quantities of the neutral as well as of the basic 
cupric acetate arc used in calico printing, for painting in oil, and 
for the manufacture of paints, especially of the so-called Schwein- 
furth green, which is a crystalline combination of copper acetate 
and arsenite. 

By gradually adding through a fine brass sieve a thin paste of 
5 parts of verdigris rubbed up in 5 parts of lukewarm water 
to a boiling solution of 4 parts of arsenious acid in 50 parts of 
water, an amorphous yellowish-green precipitate is formed which 
consists of copper arsenite and is called Scheele's green. By con- 
tinuing the heating and adding acetic acid to the boiling mixture 
it gradually becomes crystalline and acquires a very beautiful 
green color; it is then known as Schweinfurth green, and only 
requires washing with a little water and drying. The same com- 
bination can also be obtained from cupric sulphate and sodium 
arsenate and acetate. 

Schweinfurth green as found in commerce is a fine crystalline 
powder of a lustrous green color, which, however, becomes paler 
and loses some of its beauty by rubbing. It is insoluble in 
water, but is decomposed by long-continued boiling in water and 
then becomes brown. Like all copper salts it dissolves with a 
blue color in ammonia and is decomposed by alkalies and alka- 
line earths, pale-blue cupric hydrate being separated. By boiling 
the mixture the cupric hydrate is first converted into black oxide 
and then reduced by the arsenious acid to red oxide, the solution 
now containing alkaline arsenate. Mineral acids and even glacial 
acetic acid decompose the pigment by taking away the cupric 
oxide and liberating the arsenious acid. 

Schweinfurth green is much used, especially in the manufacture 
of colored .paper, wall-paper, artificial flowers, and light fabrics. 
It is, however, very poisonous, and the use of articles dyed with 
it has frequently caused sickness and even death by the dust 
reaching the respiratory organs. 



ACETATES AND THEIR MANUFACTURE. 287 

Dibasic cupric acetate and mercuric chloride (corrosive subli- 
mate) combine to a blue crystallizable combination which dis- 
solves with difficulty in water it is decomposed by boiling with 
water. 

Lead Acetates. 

With plumbic oxide acetic acid gives a neutral as well as sev- 
eral basic salts. The most important of these combinations are 
the neutral salt, known in commerce as sugar of lead, and a basic 
salt by means of which white lead is obtained. 

Neutral acetate of lead (sugar of lead), Pb(C 2 H 3 O 2 ) 2 + 3 HO. 
According to VolckePs method, acetic acid prepared from wood- 
vinegar and rectified over potassium bichromate is saturated with 
litharge, filtered or decanted, and after a further addition of acetic 
acid until a slightly acid reaction takes place, evaporated to the 
crystallizing point. 

By saturating acetic acid with litharge, a solution of basic salt 
is obtained, which is later on converted into neutral salt by the 
addition of acetic acid. This is more suitable than using only as 
much litharge as the acetic acid requires for the formation of the 
neutral salt, because the litharge dissolves with greater ease in 
solution of sugar of lead than in acetic acid. 

Solution of sugar of lead, like solution of neutral cupric acetate, 
permits the evaporation of acetic acid in boiling ; and, hence, it is 
best to use strong acetic acid, because less will have to be evapo- 
rated and the loss of acetic acid be consequently smaller. By 
taking, for instance, acetic acid of 1.057 specific gravity, for 100 
Ibs. of it 82 Ibs. of litharge are required for the formation of the 
neutral salt. A larger quantity is, however, taken (from 100 to 
180 Ibs.), so that a basic salt is formed, or, with 100 Ibs., a mix- 
ture of neutral and basic salts. To recognize the point of neu- 
tralization in the subsequent addition of acetic acid, litmus paper 
is used, or, still better, dilute solution of corrosive sublimate (1 
part of corrosive sublimate in 100 of water), which does not 
change the neutral salt, but produces turbidity' in the basic 
(Biichner). Hence, by from time to time testing the lead solu- 
tion with this reagent, the point of neutralization is reached the 



288 VINEGAR, CIDER, AND FRUIT-WINES. 

moment turbidity ceases. This test is better than with litmus, 
considerable experience being required to hit the right point with 
the latter on account of solution of sugar of lead showing a slight, 
but perceptible, acid reaction. 

The solution of litharge in acetic acid is promoted by heat and 
is effected either in a copper pan, the bottom and sides of which 
are brought in contact with a few bright sheets of lead (to pre- 
vent the copper from being attacked), or in a lead pan over an 
open fire, or in a wooden vat into which steam is introduced. 
The clear solution is evaporated. If this is to be done over an 
open fire, it is recommended to have a preparatory heating pan for 
each evaporating pan, as described in the preparation of calcium 
acetate, the preparatory heating pan, which is heated by the es- 
caping gases, being used for the solution of the litharge in acetic 
acid. Lead pans, if used, should rest upon strong cast-iron plates. 
The dimensions of the pans vary very much ; according to 
Assmus, they are 6J feet long, 4 feet wide, and from 12 to 14 inches 
deep, while the depth of the preparatory heating pans is from 24 
to 28 inches. From the latter, which stand at a higher level, 
the clear solution is discharged, through a stop-cock just above 
the bottom, into the evaporating pans. Evaporation should be 
effected at a moderate heat ; actual boiling must be strictly 
avoided, as otherwise large losses of acetic acid are unavoidable 
and the solution readily acquires a yellow coloration. 

According to the degree of evaporation (to 36 B. or to 46 B. 
or more) of the sugar of lead solution, distinct crystals are ob- 
tained or only a radiated crystalline mass. With a perfectly 
pure solution, the first method is the best, since crystals bring a 
better price. The mother-lye, after being again acidulated, is 
once more evaporated and acidulated, and yields more crystals. 

Stein recommends the conducting of the vapors of acetic acid or 
of vinegar into litharge mixed with a very small quantity of water. 
This method is in general use in Germany. But as the extract 
remaining in the still retains a considerable quantity of acetic 
acid, especially if beer had been added to the liquid used in the 
preparation of the vinegar, it is advisable to increase the boiling 
point of the latter by the addition of one-third of its weight of 
common or rock salt. At first the water condenses in the receiver 



ACETATES AND THEIR MANUFACTURE. 



289 



and the volume of the fluid containing the litharge increases, but, 
when the boiling point is reached, in the condensing vessels, only 
the acetic acid is retained, while the litharge is first converted 
into sexbasic and then into tribasic acetate. To obtain, however, 
neutral salt, either the vapors must be somewhat expanded or 
several condensing vessels placed one after the other. 

Fig. 63 shows the distilling apparatus, consisting of a boiler, a, 
of strong sheet-copper. The vapors pass through a copper-pi pe, 
6, into the wooden vat c, lined with lead, and about 35 inches in 
diameter and 67 inches deep. In this vat are four bottoms, <7, 
of thick lead provided with fine perforations. Short lead pipes, 
soldered into these bottoms and arranged as shown in the figure, 
serve to conduct the vinegar vapors in the vat to and fro in the 
interspaces between the lead bottoms. For each still at least 
three of such vats are connected with each other. Upon the 
lead bottoms is first placed a layer of linen or of flannel, and 
next a layer of litharge 2 to 4 inches deep. To prevent the 
litharge from packing, it is mixed with an equal volume of 

Fig. 63. 




pebbles about the size of a pea. The vats are provided with 
lids of sheet-copper coated with lead. From the lid of the last 
vat a pipe leads to a worm surrounded with cold water. The 
stop-cocks on the bottoms of the vats permit the discharge of the 
19 



290 VINEGAR, CIDER, AND FRUIT-WINES. 

collected lead solution, which is effected (with the use of acetic 
acid) when it shows a specific gravity of at least 36 B. The 
solution being, however, basic, it is acidulated with strong acetic 
acid and brought into the crystallizing vessels. 

This method is decidedly the best, because the evaporation" of 
the solution is entirely or almost entirely omitted and the air of 
the workroom is not contaminated by particles of sugar of lead, 
which is very injurious to the health of the workmen. Further- 
more, this method does not require the use of pure acetic acid, 
since the impurities remain in the still. This, however, holds 
good only for non-volatile impurities. For the production of 
colorless salt, the crude acetic acid from wood-vinegar must 
necessarily be purified, as above mentioned, by potassium chro- 
matc and sulphuric acid. 

The crystallizing pans are either of stone- ware or of wood 
lined with lead or thin copper, to which is soldered a strip of lead 
down the sides and across the bottom, with the idea of rendering 
the metal more electro-negative so as to prevent the acetic acid 
from acting on it. The wooden crystallizing pans are about 4 
feet long by 2 feet wide and from 6 to 8 inches deep, sloping 
inwards at the edges. Shallow, slightly conical copper vessels 6 
inches deep with a diameter of 29 J inches at the bottom and 31 J 
inches at the top are also used. The stone- ware pans are placed 
upon a slightly inclined level covered with lead. In these small 
pans crystallization is complete in 24 hours, while from 48 to 72 
hours are required with the use of the larger wooden vessels. 
Crystallization being complete, the mother-lye is removed and 
the vessels placed upon a wooden frame over a gutter of sheet- 
lead to drain off, as. shown in Figs. 64 and 65. 

If especially beautiful crystals are to be obtained, the first 
crystals, which are not very distinct, are again dissolved in 
the water obtained by the condensation of the vapors escaping 
from the still. The solution being evaporated to the proper 
density is again allowed to crystallize. The crystals after suffi- 
cient draining are placed upon linen spread over wooden hurdles 
and dried at a moderate heat, not exceeding 75 F. In some 
factories the heated air of a stove, placed outside the drying 
house, is conveyed through pipes passing round the interior ; at 



ACETATES AND THEIR MANUFACTURE. 



291 



other places steam heat is employed for this purpose, which is 
much to be preferred on account of its being more easily regu- 
lated. 



Fig. 64. 



Fig. 65. 




When working on a large scale a centrifugal is advantageously 
employed for the separation of the niother-lye in the same manner 
as recommended for the preparation of sodium acetate (p. 243). 

Litharge being quite impure plumbic oxide never dissolves 
entirely, and frequently contains over 10 per cent, of impurities, 
consisting of sand, clay, red lead or minium (Pb 3 O 4 ), metallic lead, 
traces of silver, cupric, and ferric oxides. The cupric oxide 
passes into the sugar of lead solution and colors it slightly blue. 
To separate the copper bright sheets of lead are dipped into the 
solution, the copper separating upon them in the form of a dark 
slime. The sheets of lead must be frequently cleansed (scraped), 
as otherwise they lose their effect. When there is a large accu- 
mulation of litharge residue, it can be worked for silver. 

Sugar of lead can also be prepared from metallic lead, the pro- 
cess having been recommended first by Berard, and is said, by 
Rtmge, to yield a good product with great economy. Granulated 
lead, the tailings in the white lead manufacture, etc., are put in 
several vessels, say eight, one above the other, upon steps, so 
that the liquid may be run from one to the other. The upper 
one is filled with acetic acid, and after half an hour let off into 
the second, after another half an hour into the third, and so on 
to the last or eighth vessel. The acid causes the lead to absorb 
oxygen so rapidly from the air as to become hot. When the acid 
runs off from the lowest, it is thrown on the uppermost vessel a 
second time and carries off the acetate of lead formed ; after pass- 



292 VINEGAR, CIDER, AND FRUIT-WINES. 

ing through the whole series the solution is so strong that it may 
be evaporated at once so as to crystallize. 

Apparently this method has a considerable advantage over that 
with litharge, metallic lead being cheaper and producing more 
sugar of lead (entirely free from copper) than litharge, because 
103.5 Ibs. of pure lead yield 189.5 Ibs. of sugar of lead, while 
the same quantity is only obtained from 111.5 Ibs. of pure litharge. 
Furthermore, commercial lead is always purer than litharge. On 
the other hand, this process has the disadvantage of a consider- 
able quantity of acetic acid being lost by evaporation on account 
of it having to pass through several vessels. The manufacture 
of sugar of lead is most suitably combined with that of white 
lead, it being thus possible to utilize the tailings, etc. to greater 
advantage than, as is frequently done, by melting them together 
and remelting, which always cause considerable loss. 

Sugar of lead is further formed by boiling lead sulphate with 
a very concentrated solution of barium acetate, barium sulphate 
(permanent white) being thereby precipitated. For 100 parts of 
lead sulphate 84 parts of anhydrous or 100 of crystallized barium 
acetate are required, the yield being 125 parts of sugar of lead. 
Sulphate of lead is obtained in large quantities as a by-product 
in the preparation of aluminium acetate. 

For many purposes of dyeing and printing the use of pure 
sugar of lead is not necessary, the brown acetate of lead answer- 
ing all requirements. For its preparation ground litharge is 
introduced in small portions, and with constant stirring into dis- 
tilled pyroligneous acid in a vat until red litmus paper is colored 
blue, and, hence, a basic salt is formed. The impurities separat- 
ing on the surface are removed and the clear fluid is then trans- 
ferred to a copper pan provided with strips of lead, and evaporated 
to about two-thirds its volume, the brown smeary substances 
rising to the surface during evaporation being constantly removed. 
By again diluting and slightly acidulating the concentrated fluid 
a further portion of the foreign substances can be removed. 
Finally evaporation is carried to the crystallizing point, i. e., 
until a few drops congeal when allowed to fall upon a cold 
metal plate. An addition of animal charcoal for the purpose of 
discoloration is of no advantage ; the coloration is not completely 



ACETATES AND THEIR MANUFACTURE. 293 

removed,, and the little effect produced is attained by a considerable 
loss of salt which is absorbed by the animal charcoal. 

By disturbing crystallization by constant stirring during cooling 
a nearly amorphous mass having the appearance of yellow wax is 
obtained, which is much liked by many consumers. The product 
thus obtained is not always a neutral salt, but sometimes a mix- 
ture of neutral and basic salt (besides empyreumatic substances). 
After cooling it must, therefore, be quickly and well packed in 
order to protect it from the moisture and the carbonic acid of the 
air. The sugar of lead solution may, however, also be evapo- 
rated only so far that some mother-lye remains after cooling ; the 
crystallized mass is then allowed to stand in a moderately warm 
room for some time. In consequence of capillarity the impurities, 
which occur chiefly in the inother-lye, gradually rise up between 
the crystals, a slight coating of a yellow, or brown, smeary sub- 
stance being finally formed upon the mass of crystals and can 
be readily removed. 

The linen upon which the crystals are dried must be carefully 
protected from fire, as it ignites from the slightest spark and burns 
like tinder. 

If the hot solution be set aside to cool rapidly, the sugar of lead 
crystallizes in clusters of fine needles ; but if the evaporation be 
conducted slowly the crystals are truncated and flattened, quad- 
rangular and hexahedral prisms derived from a right rhombic 
prism. Acetate of lead has a sweet astringent taste, is soluble in 
1J parts of water and in 8 parts of ordinary alcohol. The crys- 
tals are permanent in the air, but are apt to effloresce and become 
anhydrous if the temperature ranges between 70 and 100 F. 

Acetate of lead consists of 

Plumbic oxide ........ 58.9 

Anhydrous acetic acid . . . . . . ' 26.9 

Water ......... 14.2 

100.00 

Aqueous solution of sugar of lead slightly reddens litmus 
paper, but shows an alkaline reaction upon turmeric, browning 
this coloring substance. 

At 167 F. the crystals of acetate of lead melt, and but slowly 
yield up their water ; by heating the entirely dephlegmated salt 



OF TH2 

7BR 

V C'jt _ *>* ^ W Ji 



294 VINEGAR, CIDER, AND FRUIT- WINES. 

more strongly it fuses at 536 F. to a clear, oil-like, colorless 
fluid and decomposes above this temperature, evolving all the 
compounds usually obtained in the destructive distillation of the 
acetates of the heavy metals, leaving a residue of metallic lead in 
a very minute state of division with some charcoal. When this 
distillation is conducted in a glass tube closed at one end and 
having the other drawn out for convenience of sealing, at the end 
of the operation, the well-known lead pyrophorus is made. The 
particles of metallic lead are so small that, when thrown into the 
air, oxygen molecules come into such intimate contact with them 
that ignition is effected from the rapidity with which lead oxide 
is formed. 

A slight decomposition occurs when the neutral salt is exposed 
to an atmosphere of carbonic acid, carbonate of lead being formed ; 
the portion of acetic acid thus liberated protects the remainder 
from further change. 

Cold solution of sugar of lead is not immediately changed by 
ammonia ; by adding, however, a strong excess, sexbasic acetate 
of lead is gradually separated ; on boiling yellow-red crystalline 
lead oxide is precipitated. 

The introduction of chlorine gas into a solution of sugar of 
lead produces in a short time a brown precipitate of plumbic di- 
oxide ; bromine acts in a similar manner, but on account of its 
insolubility iodine produces scarcely any effect. 

Solution of calcium chloride at once produces a yellow pre- 
cipitate, which gradually becomes brown. 

Sugar of lead containing considerable copper has a bluish ap- 
pearance ; if the content of copper is small, it is recognized by the 
solution acquiring a blue coloration with ammonia, or, still better, 
by mixing the solution of sugar of lead with an excess of solution 
of Glauber's salt and testing the filtrate with potassium ferro- 
cyanide ; a dark red precipitate indicates copper. 

Sugar of lead, as well as the basic lead salts to be mentioned 
further on, possesses poisonous properties. 

Sugar of lead is chiefly used for the preparation of aluminium 
acetate as well as of other acetates. Large quantities of it are 
also consumed in the manufacture of colors, for instance, of neu- 
tral and basic lead chromate, chrome yellow, chrome orange, and 



ACETATES AND THEIR MANUFACTURE. 295 

chrome red. Upon the cloth-fibre (especially wool) chrome yel- 
low and chrome orange are produced by means of sugar of lead, 
especially with the brown variety ; the latter product being also 
very suitable for the production of the so-called chrome green, 
which is obtained by the joint precipitation of chrome yellow and 
Berlin blue. 

Xeutral lead acetate gives crystallizable double salts with 
potassium acetate and sodium acetate as well as with lead nitrate, 
lead chloride, lead bromide, etc. 

Basic lead acetates. Several of these compounds are known. 
Those with 2 and 3 equivalents of plumbic oxide to 1 equivalent 
of acetic acid are soluble in water, show a strong alkaline reac- 
tion, and with carbonic acid the solutions yield at once and in 
every degree of concentration abundant precipitates of white lead 
(basic carbonate of lead), while, when the operation is at a suita- 
ble moment interrupted, neutral salt remains in solution. In this 
manner white lead is manufactured according to the so-called 
French method (of Thenard and Hoard) at Clichy and other 
places in France as well as in different German factories. If, 
however, the introduction of carbonic acid be continued until no 
more precipitate is formed, a part of the lead of the neutral salt 
is also precipitated as carbonate, which, however, is neutral, and 
an acid solution remains behind. 

The soluble salt known as lead-vinegar or extract of lead is pre- 
pared by digesting 2 parts of sugar of lead dissolved in 5 of 
water with 1 of finely powdered litharge. The proportional 
quantities of sugar of lead, litharge, and water prescribed by the 
Pharmacopoeias of the different countries vary very much, and, 
consequently, also, the compositions and specific gravities (from 
1.20 to 1.36) of the solutions of lead prepared in accordance witli 
them. The litharge dissolves very readily in the sugar of lead 
solution, in fact with greater ease than in acetic acid, and espe- 
cially with greater rapidity if the sugar of lead solution be heated 
in a silver dish to the boiling point and the litharge gradually 
introduced. For the manufacture on a large scale, the sugar of 
lead solution and the litharge may be brought into a barrel revolv- 
ing around its axis. If the operation is to be conducted at the 
ordinary temperature, the barrel must be closed to prevent the 



296 VINEGAR, CIDER, AND FRUIT-WINES. 

access of the carbonic acid of the air. Very remarkable is the 
behavior of the tribasic acetate towards hydrogen dioxide; plum- 
bic dioxide is first formed, but in a short time this exerts a de- 
composing influence upon the hydrogen dioxide which may be 
present in excess, so that both dioxides now lose one-half of their 
oxygen, which evolves in the form of gas, and water and plumbic 
oxide are formed.* Now, as freshly precipitated plumbic di- 
oxide possesses the further property of decomposing solution of 
potassium iodide, Schoenbein recommends tribasic acetate of lead 
together with paper coated with paste prepared with potassium 
iodide as the most sensitive re-agent for hydrogen dioxide. 

Lead sesquibasic acetate, triphimbic tetracetate. This salt is ob- 
tained by heating the diacetate until it becomes a white, porous 
mass; this is re-dissolved in water and set aside to crystallize. 
Sesquibasic acetate is soluble in both water and alcohol ; its solu- 
tions are alkaline. 

Tribasic acetate of lead is prepared by digesting 189.5 Ibs. of 
sugar of lead with 223 Ibs. of plumbic oxide (pure) or 3 Ibs. of 
sugar of lead to 4 Ibs. of litharge ; or, according to Payen, into 
100 volumes of boiling waiter are poured 100 volumes of aqueous 
solution of sugar of lead saturated at 86 F., and afterwards a 
mixture of pure water at 140 F., with 20 volumes of ammonia 
liquor free from carbonate. The vessel is then immediately 
closed, and in a short time an abundance of the tribasic acetate 
crystallizes out. This salt presents itself under the form of long 
needles. It is insoluble in alcohol, very soluble in water, its so- 
lution being alkaline. Tribasic acetate is the most stable of all 
the subacetates of lead. It takes a leading part in the manufac- 
ture of white-lead by the Clichy process ; it is, in point of fact, a 
solution of this salt which is decomposed by the carbonic acid, 
and gives rise to the carbonate of lead, being itself at the same 
time converted into lead diacetate. In the Dutch process the 
formation of lead carbonate is, according to Pelouze, also due to 
the formation of tribasic acetate on the surface of the sheets of 
lead, which is, in its turn, decomposed by the carbonic acid. 

Sexbasic acetate of lead. This body is prepared by digesting 

* Schoenbein in Wagner's Jahresbericht, 1862. 



ACETATES AND THEIR MANUFACTURE. 297 

any of the preceding salts with lead oxide. It is a white powder 
slightly soluble in boiling water, from which it crystallizes out in 
silky needles which consist of 2 equivalents of the salt combined 
with three equivalents of water. 

Uranium acetate. With uranous oxide acetic acid combines 
to a dark green crystallizable salt, and with uranic oxide to a 
yellow basic salt, which, combined with water, appears in two 
different forms of crystals. It is remarkable for giving, with 
many other acetates, well crystallizing salts, of a beautiful color 
and partly showing magnificent dichroism (Wertheim and 
Weselsky). 

Tin acetate is prepared by dissolving stannous hydrate* in 
heated strong acetic acid, or by mixing stannous chloride (SnCl 2 ) 
with acetate of sodium or calcium. It forms small colorless 
needles which have a strong metallic taste and readily decompose 
in the air. The salt is sometimes used as a mordant in calico 
printing. 

Bismuth acetate. Bismuth nitrate prepared by gradually in- 
troducing pulverized metallic bismuth into cold dilute nitric acid 
is mixed with pure concentrated sugar of lead solution. The 
salt separates in small, colorless needles. 

Mercurous acetate can be prepared by dissolving pure mercu- 
rous oxide or its carbonate in acetic acid, or by mingling hot solu- 
tions of mercurous nitrate and acetate of sodium or of potas- 
sium. The pure mercurons carbonate is heated to boiling with 8 
parts of water, and concentrated acetic acid added until all is dis- 
solved ; the hot, filtered liquid free from oxide being allowed to 
cool. Or, acidulated nitrate is diluted with 6 to 8 parts of water, 
heated and mixed with one equivalent of acetate of sodium or 
potassium, dissolved in 8 parts of hot water containing a little 
free acid and cooled. The salt, when separated, is washed with 
a little cold water, dried in the dark at a gentle heat, and kept 
from the light in covered bottles. 

It crystallizes in fine, white, silvery scales, flexible and unctuous 
to the touch, with a nauseous metallic taste, easily decomposed by 

* The hydrate is obtained by precipitating stannous chloride with soda lye 
and washing the precipitate. 



298 VINEGAR, CIDER, AND FRUIT-WINES. 

light ; it is dissolved with difficulty in cold water, requiring 33 
parts at the ordinary temperature. It is partially decomposed 
by boiling water into acid and basic salts of both oxides and me- 
tallic mercury. It is used in pharmacy. 

Mercuric acetate. Dissolve red oxide of mercury in concen- 
trated acetic acid with a gentle heat and evaporate to dry ness, or 
partially to crystallization, or by spontaneous evaporation. By 
the first process, it is a white saline mass ; by the second, it forms 
crystalline scales ; and by the third, four-sided plates, which are 
partly transparent, partly pearly and translucent ; anhydrous, of 
a nauseous metallic taste, fusible without decomposition, solidify- 
ing to a granular mass, but its point of decomposition is near 
that of fusion. It dissolves in 4 parts of water at 50 F., in 2.75 
at 66.2 F., and in 1 at 212 F., but by boiling it is partly de- 
composed, with separation of red oxide ; even in the air its solu- 
tion suffers the latter change and contains a basic salt. With 
free acetic acid it is not decomposed ; 1 00 parts of alcohol dis- 
solve 5-| of this salt, and this solution behaves like the aqueous 
one. It generally contains, except when carefully crystallized, 
some mercurous oxide. 

Silver acetate. This salt is obtained by precipitating a concen- 
trated solution of silver nitrate with a concentrated solution of 
sodium acetate. It forms a white crystalline precipitate. It dis- 
solves in about 100 parts of cold, but readily in hot water, and 
only sparingly in alcohol. On exposure to light it acquires a 
dark color, being partially reduced. On heating, it yields acetic 
acid, metallic silver remaining behind. 

If the salt be heated with bisulphide of carbon in a closed 
glass tube to 329 F., silver sulphide, carbonic acid, and anhy- 
drous acetic acid are formed (Broughton). 

On treating the dry salt with iodine, lively decomposition takes 
place, whereby silver iodide, some metallic silver, and coal re- 
main behind, while methyl oxide, acetic acid, acetylene, and hy- 
drogpn appear. With iodine a solution of this salt yields acetic 
acid, silver iodide, and iodate of silver (Birnbaum). 



PART II. 

MANUFACTURE OF CIDERS, FRUIT-WINES, ETC. 
CHAPTER XXIV. 

INTRODUCTION. 

THE term wine in general is applied to alcoholic fluids which 
are formed by the fermentation of fruit juices and serve as beve- 
rages. According to this definition, there may be actually as many 
kinds of wine as there are fruits whose juices, in consequence of 
their content of sugar, are capable of vinous fermentation ; and, in 
fact, besides the apple and pear, there are many other fruits 
which are likewise applicable to wine-making. Among these 
may be named currants, gooseberries, mulberries, elderberries, 
cherries, oranges, dates, pine-apples, raspberries, strawberries, 
etc. But, in order to make the product from such fruits re- 
semble the standard wine made from grapes, various ingredients 
have to be added, as, for instance, an acid, spices, coloring, and 
an astringent, to replace the extractive matter. The acid gene- 
rally used is the tartaric, and elderberry and whortleberry juice are 
used for the coloring, while the water used in the manufacture of 
wine should in all cases be pure and soft. 

Ripening of fruits. In order to form a clear idea of the pro- 
cesses which take place during the growth, ripening, and final 
decomposition of a fruit, it is necessary to refer to the constitu- 
ents which are already found in an unripe fruit at its first appear- 
ance. 

Besides water, the quantity of which varies between 90 and 45 
per cent., fruits contain partly soluble and partly insoluble sub- 
stances. The juice obtained by pressure contains the soluble con- 
stituents, such as sugar, gum, tannin, acids, salts, etc., while the 



300 VINEGAR, CIDER, AND FRUIT-WINES. 

remaining insoluble portion consists chiefly of cellulose, starch, 
a gum-like body, a few inorganic substances, and, further, the 
characteristic constituent of unripe fruits, to which the term pec- 
to#e has been applied. It forms the initial point for the phe- 
nomena observed during the growth and ripening of fruits, and, 
therefore, requires a somewhat closer examination. 

In regard to its behavior, pectose approaches cellulose and 
starch ; it is chiefly found in the pulp of unripe fruits, but also 
in certain roots, especially in carrots, beets, and others. It is 
insoluble in water, spirits of wine, and ether, but during the 
ripening of the fruit it undergoes a change, induced by the acids 
and heat, and is converted into pectine, which is readily soluble 
in water. To pectose are due the hardness of unripe fruits and 
also the property of many fruits and roots of boiling hard in 
water containing lime, the pectose combining with the lime. 

The formation of pectine commences as soon as the fruits are 
exposed to the action of heat, and then depends on the influence 
of the vegetable acid present upon he pectose. To be convinced 
of this it suffices to express the pulp of an unripe apple. The 
juice thus obtained contains scarcely a trace of pectine, but, by 
boiling it for a few minutes with the pulp of the fruit, the fluid, 
in consequence of the formation of pectine, acquires a viscous 
quality, like the juice obtained from ripe fruits. 

Pectine, nearly pure, is white, soluble in water, non-crystal- 
lizable, and without effect upon vegetable colors. From its 
dilute solution it is separated as a jelly by alcohol, and from its 
more concentrated solution, in long threads. Brought into con- 
tact with alkalies or alkaline earths, pectine is transformed into 
pectic acid. Under the influence of a peculiar ferment called 
pectase, which will be described later on, pectine is transformed 
into pectosic acid, and by dilute acids into metapectic acid. 

By boiling a solution of pectine in water for a few hours, it 
partially loses its viscous condition and separates a substance 
called parapectine, which shows the same behavior as pectine, 
except that it is not precipitated by neutral lead acetate. When 
treated with dilute acids the parapectine is transformed into meta- 
pectine, which might be called metapectous acid, as it shows a 
decidedly acid reaction and colors litmus paper strongly red. 



RIPENING OF FRUITS. 301 

Metapectine is soluble in water, non-crystallizable, and, like 
pectine and parapectine, insoluble in alcohol, which precipitates 
it from its solutions in the form of a jelly. On being brought 
into contact with bases it is also transformed into pectic acid. It 
differs from pectine and parapectine in that the solution is pre- 
cipitated by barium chloride. 

Pectase, the peculiar ferment previously referred to, is similar 
in its mode of action to diastase and emulsin. It can be obtained 
by precipitating the juice of young carrots with alcohol, whereby 
the pectose, which was at first soluble in water, becomes insoluble, 
without, however, losing its effect upon the pectous substances. 

By adding pectase to a solution of pectine, the latter is imme- 
diately converted into a jelly-like body, insoluble in water. This 
phenomenon is the pectous fermentation, which may be compared 
with lactic acid fermentation. It is not accompanied by an evo- 
lution of gas, and may take place with the air excluded, a tem- 
perature of 86 F. being most favorable for its progress. 

Pectase is an amorphous substance ; by allowing it to stand in 
contact with water for a few days, it decomposes, becomes cov- 
ered with mold-formations, and loses its action as a ferment, the 
latter being also destroyed by continued boiling. In the vege- 
table organism it occurs in a soluble as well as insoluble state. 

Roots such as carrots, beets, etc. contain soluble pectase, and 
their juice added to a fluid containing pectine in solution imme- 
diately induces pectous fermentation, while the juice of apples 
and other acid fruits produces no effect upon pectine, the latter 
being present in them in the modified insoluble form and accom- 
panying the insoluble portion of the pulp. On adding the pulp 
of unripe apples to a pectine solution it gelatinizes in a short 
time in consequence of the formation of pectosic and pectine 
acids. 

Pectosic acid is the result of the first effect of the pectase upon 
pectine ; it is, however, also formed by bringing dilute solutions of 
potash, soda, ammonia, or alkaline carbonates in contact with 
pectine. In all these cases salts are formed which, when treated 
with acids, yield pectosic acid. The latter is jelly-like and dissolves 
with difficulty in water ; in the presence of acids it is entirely 



302 VINEGAR, CIDER, AND FRUIT-WINES. 

insoluble ; by long boiling in water, by pectase, or by an excess 
of alcohol it is soon transformed into pectic acid. 

By allowing pectase to act for some time upon pectine, pectic 
acid is formed ; the same conversion taking place almost instan- 
taneously by dilute solution of potash, soda, ammonia, alkaline 
carbonates, as well as by barium, lime, and strontium water. Its 
formation in the above-described manner is preceded by that of 
pectosic acid, which, as previously mentioned, is converted by the 
same agents into pectic acid. 

Pectic acid is insoluble in cold, and scarcely soluble in hot, 
water; by boiling it, however, for a certain time in water, and 
constantly replacing the water lost by evaporation, it disappears 
entirely, and is converted into a new acid soluble in water. By 
nitric acid it is transformed into oxalic acid and muric acid ; 
alkalies decompose it very rapidly, the final result being metapec- 
tic acid, which is soluble in water, but non-crystallizable ; on 
boiling in hot water, the solution forms a jelly after cooling. 

Pectic acid further possesses the special property of dissolving 
in a large number of alkaline salts and forming with them true 
double salts which always show a decidedly acid reaction, dissolve 
in water, and on cooling form consistent jellies. 

By boiling for a few hours a solution of a pectous salt, the latter 
is transformed into a parapectous salt which, when decomposed 
by a dilute acid, yields parapectic acid. It is non-crystallizable, 
shows a strong acid reaction, and forms soluble salts with alkalies ; 
it is precipitated by barium water in excess. 

Metapectic acid is formed in various ways, among others by 
leaving an aqueous solution of parapectic acid to itself for some 
time, but also by the action of the lime contained in the cell-tissue 
of roots and fruits upon pectose. It is insoluble in water, does not 
crystallize, and gives soluble salts with all bases. With an excess 
of bases the salts acquire a yellow coloration ; they are precipi- 
tated by basic lead acetate. 

What has been said in the preceding may be briefly condensed 
as follows : 

1. By the influence of heat upon pectose pectine is formed. 

2. Pectine is transformed into parapectine by boiling its aque- 
ous solution for several hours. 



RIPENING OF FRUITS. 303 

3. Parapecti rie/when treated at a boiling heat with dilute acids, 
is converted into metapectine. 

4. Pectase converts pectine into pectic acid. 

5. By long-continued action of pectase upon pectine pectic 
acid is formed. 

6. Pectic acid is transformed by boiling water into parapectic 
acid. 

7. An aqueous solution of parapectic acid is quickly converted 
into metapectic acid. 

All these bodies are derived from pectose, which through all 
these transformations has not even suffered a change in the pro- 
portion of weight of its constituents (carbon, hydrogen, and 
oxygen ) ; hence all have the same qualitative and quantitative 
composition. This may, perhaps, sound odd, but chemistry pre- 
sents numerous analogies for such cases, and hence the term 
isomeric has been applied to bodies which with the same quanti- 
tative composition exhibit very different chemical properties. 

The changes pectose undergoes by the influence of heat, a 
peculiar ferment, acids and alkalies, and the resulting combina- 
tions mentioned above, have of course been artificially effected by 
chemical means. They resemble, however, so closely the state of 
fruits in the course of their growth and ripening, and the influ- 
ences and conditions to which fruits are exposed in nature are 
sufficiently similar to those artificially induced, that their action 
may be reasonably supposed to be the same. We know from 
daily experience that heat promotes the development and ripening 
of fruit ; fruits contain pectose and acids, and alkalies or bases are 
conducted to them from the soil ; hence in fruit in a normal state 
of development none of the chemical agents are wanting which the 
chemist uses for the production of derivatives of pectose. 

If the transformation of substances under the influence of others 
be considered as dependent on chemical processes, the develop- 
ment of a fruit from its first formation to complete ripeness, and 
even to its decomposition, rotting, and putrefaction, is a chemical 
process in the widest sense of the word. This is evident, not 
only from what has been said in the preceding, but has also 
been plainly shown by special chemical researches into the changes 



304 VINEGAR, CIDER, AND FRUIT- WINES. 

fruits undergo during their development and perfection. The 
results of these researches are briefly as follows : 

1. The quantity of water contained in the pulp of a fruit is con- 
siderable ; it varies between 45 and 90 per cent. In many fruits 
the content of water remains unchanged during the different 
periods of ripening, but, as a rule, it is somewhat greater in the 
commencement. 

2. Fruits of the same kind examined at the same season of the 
year alwavs contain the same quantity of water ; the same holding 
good as regards the various parts of the pulp of a fruit. 

3. The solid constituents in the pulp of fruits amount to be- 
tween 10 and 25 per cent.; they consist of soluble substances, 
which dissolved in the water form the juice of the fruits ; and of 
insoluble bodies which compose the membranes of the cells. 

4. The quantity of soluble substances always increases with 
increasing ripeness, while the weight of the insoluble decreases ; 
hence it may be said the soluble substances contained in the juice 
of a fruit are formed at the expense of the insoluble portion of 
the pulp. The bodies which become soluble are starch, pectose, 
and a gum-like substance capable of being converted into gum. 

On this modification of the solid portion of the pulp of a fruit 
depend also the changes a fruit undergoes in regard to hard- 
ness and transparency during ripening. 

According to the mode of action of the pectase and acids upon 
the pectose, all ripe fruits contain pectine. 

5. Various acid fruits, such as plums, cherries etc., are fre- 
quently observed to secrete a neutral juice which, in consequence 
of the evaporation of the water, leaves a gum-like substance upon 
the exterior of the fruit. This phenomenon throws some light 
upon the separation of gum as it appears in many trees, and which, 
when it occurs very abundantly, is an actual disease. 

In fruits becoming thus covered with gum a transparent, 
neutral substance insoluble in water occurs stored in the cells of 
the pulp. Under the influence of nitrogenous substances, which 
act as a ferment, and perhaps also of acids, this gum-like substance 
is modified and transformed into actual gum, which is then con- 
verted into sugar in the interior of the pulp of the fruit ; an ex- 



RIPENING OF FRUITS. 305 

cess of this gum-like substance is secreted and forms a firm 
coating upon the exterior of the fruit. 

6. The sugar occurring in ripe fruits is evidently derived from 
various sources. The occurrence of a large quantity of starch in 
many unripe fruits, especially in apples, and its complete disap- 
pearance at the time of ripeness, allow of no other explanation 
than that the sugar occurring in fruits is formed by the conversion 
of the starch under the influence of the acids present ; other in- 
different substances, such as gum, vegetable mucus, etc., undergo 
similar transformations and yield in this manner a certain portion 
of sugar. Even tannin, which occurs in all unripe, but not in 
ripe fruits, can be changed by acids and ferments so as to form 
sugar. 

Thus far nothing justifies the supposition that the acids in 
fruits, such as tartaric, citric, malic acids, are converted into 
fruit-sugar. To entertain such an opinion it would have to be 
supposed that the molecules of these acids, which are far more 
simple than those of fruit-sugar, become more complex and are 
converted into sugar ; in such natural transformations the reverse 
is, however, generally the case, the molecules always endeavoring 
to become the more simple the farther they withdraw from organ- 
ized structures. 

7. It has been attempted to explain in various ways the very 
remarkable phenomenon of the gradual disappearance of the 
acids in ripening fruits. It might not be impossible that the acid 
of a fruit is neutralized by the bases conducted to it through the 
juice ; or that it is covered by the sugar or the mucous substances 
formed in the juice ; or, finally, that it disappears at the moment 
of ripeness by suffering actual combustion. An examination of 
these various opinions leads to the conclusion that the acid is 
neither neutralized nor covered by the sugar or the mucous sub- 
stances, but that it actually undergoes slow combustion. 

During development and ripening a fruit passes through two 
different stages sharply separated from each other by definite 
chemical phenomena. In the first stage, which may be desig- 
nated as that of growth, whilst the fruit remains green, its rela- 
tion to the atmosphere appears the same as that of leaves, for it 
absorbs carbonic acid and evolves oxygen. During this epoch it 
20 



306 VINEGAR, CIDER, AND FRUIT-WINES. 

increases rapidly in size, and receives through the stem the inor- 
ganic substances indispensable for its development, and water. If, 
at this stage, it is taken from the tree, it soon commences to 
wither and decay. But in the second period, when it fairly 
begins to ripen, its green color is, as a rule, replaced by a yellow, 
brown-red, or red. Oxygen is now absorbed from the air and 
carbonic acid is evolved, whilst the starch and cellulose are con- 
verted into sugar under the influence of the vegetable acids, and 
the fruit becomes sweet. When the sugar has reached the maxi- 
mum the ripening is completed ; if the fruit be kept longer, the 
oxidation takes the form of ordinary decay. 



CHAPTER XXV. 

FRUITS AND THEIR COMPOSITION. 

FOR the preparation of fruit-wines, not only the fruits culti- 
vated in our gardens and orchards on account of their fine flavor 
are used, but sometimes also others which do not by any means 
possess an agreeable taste, and whose juices after fermentation 
yield a product which has at least only a very doubtful claim to 
the name of " wine." The utilization of such material for wine- 
making can only be explained by special fancy, and hence here 
only such fruits will be considered as, on account of the nature 
of their juices, will yield with rational treatment a beverage of 
a sufficiently agreeable taste to be liked. 

For the fabrication of fruit-wine, sugar not only by itself but 
also in its proportion to the free acid present, is undoubtedly the 
most important constituent of the fruit. The following compila- 
tion from Fresenius gives the average percentage of sugar in 
different varieties of fruit. 



FRUITS AND THEIR COMPOSITION. 



307 



Peaches 
Apricots 
Plums . 
Reine Claudes 
Greengages . 
Raspberries 
Blackberries 
Strawberries 
Whortleberries 



1.57 p. c. 


Currants 


. 6.10 p. c. 


1.80' " 


German prunes . 


. 6.25 " 


2.12 " 


Gooseberries 


. 7.15 " 


3.12 " 




7 45 " 


3.58 " 


Apples 


. 8.37' " 


4.00 " 


Sour cherries 


. 8.77 " 


4.44 " 


Mulberries . 


. 9.19 < 


5.73 " 


Sweet cherries 


. 10.79 " 


5.78 " 


Grapes 


. 14.93 " 



II. Compilation according to average percentage of free acid 
expressed in malic acid. 



Pears . 

Greengages . 
Sweet cherries 
Peaches 
Grapes 
Apples 

German prunes 
Reine Claudes 
Apricots 



0.07 p. c. 


Blackberries 


0.58 " 


Sour cherries 


0.62 " 


Plums 


0.67 " 


Whortleberries 


0.74 " 


Strawberries 


0.75 " 


Gooseberries 


0.89 " 


Raspberries 


0.91 " 


Mulberries . 


1.09 " 


Currants 



1.19 p. c. 

1.28 " 

1.30 " 

1.34 " 

1.37 " 

1.45 " 

1.48 " 

1.86 " 

2.04 " 



III. Compilation according to the proportion between acid, 
sugar, pectine, gum, etc. 









Pectine, 




Acid. 


Sugar. 


gum, etc 


Plums 


. I 


1.63 


3.14 


Apricots 


. 1 


1.65 


6.35 


Peaches 


. 1 


2.34 


11.94 


Raspberries 


. 1 


2.70 


0.96 


Currants 


. 1 


3.00 


0.07 


Reine Claudes 


. 1 


3.43 


11.83 


Blackberries 


. 1 


3.73 


1.21 


Whortleberries . 


. 1 


4.31 


0.41 


Strawberries 


. 1 


4.37 


0.08 


Gooseberries 


. 1 


4.93 


0.76 




. 1 


4.94 


1.10 


Greengages 


. 1 


6.20 


9.92 


Sour cherries 


. 1 


6.85 


1.43 


German prunes . 


. 1 


7.03 


4.35 


Sweet cherries 


. 1 


11.16 


5.60 


Grapes 


. 1 


20.18 


2.03 


Pears 


1 


94.60 


44.40 



TV. Compilation according to the proportion between water, 
soluble and insoluble substances. 



308 



VINEGAR, CIDER, AND FRUIT-WISES. 



Raspberries 

Blackberries 

Strawberries 

Plums 

Currants 

Whortleberries 

Gooseberries 

Greengages 

Apricots 

Pears . 

Peaches 

German prunes 

Sour cherries 

Mulberries . 

Apples 

Reine Claudes 

Sweet cherries 

Grapes 



Composition of the juice, 
in 100 parts, without the 


insoluble substances. 




Soluble 


Insoluble 




Soluble 


Water. 


substances. 


substances. 


Water. 


substances. 


100 


9.12 


6.88 


91.64 


8.36 


100 


9.26 


6.46 


91.53 


8.47 


100 


3.39 


5.15 


91.42 


8.58 


100 


9.94 


0.87 


91.13 


8.87 


100 


11.00 


6.62 


90.09 


9.91 


100 


12.05 


16.91 


89.25 


10.75 


100 


1218 


3.57 


89.14 


10.86' 


100 


13.04 


1.53 


88.46 


11.54 


100 


13.31 


2.07 


88.25 


11.75 


100 


14.25 


5.54 


87.52 


12.48 


100 


14.64 


2.10 


87.23 


12.77 


100 


15.32 


3.15 


86.71 


13.29 


100 


16.48 


1.31 


85.85 


14.15 


100 


16.57 


1.47 


85.79 


14.21 


100 


16.89 


3.61 


85.46 


14.54 


100 


18.52 


1.22 


84.37 


15.63 


100 


18.61 


1.53 


84.30 


15.70 


100 


22.81 


5.81 


81.42 


18.58 



V. Composition of the juice according to its content of sugar, 
peetine, etc., in 100 parts. 







Peetine, 






Peetine 




Sugar, 


etc., 




Sugar, 


etc., 




p. c. 


p. c. v 




p. c. 


p. c. 


Peaches 


. 1.99 


10.05 


German prunes 


. 7.56 


4.70 


Reine Claudes 


. 2.04 


6.98 


Gooseberries 


. 8.00 


1.24 


Apricots 


. 2.13 


8.19 


Whortleberries 


. 8.12 


0.77 


Plums . 


. 2.80 


5.40 


Pears . 


. 8.43 


4.02 


Greengages . 


. 4.18 


6.45 


Apples 


. 9.14 


4.59 


Raspberries 


. 4.84 


1.73 


Mulberries . 


. 10.00 


2.22 


Blackberries 


. 5.32 


1.72 


Sour cherries 


. 10.44 


2.17 


Strawberries 


. 6.89 


0.13 


Sweet cherries 


. 15.30 


2.43 


Currants 


. 7.30 


0.16 


Grapes 


. 16.15 


2.07 



VI. Content of free acid in 100 parts of juice. 



Pears . 
Reine Claudes 
Greengages . 
Grapes 
Apples 
Peaches 
Sweet cherries 
German prunes 
Apricots 



0.09 p. c. 


Blackberries 


0.59 " 


Sour cherries 


0.67 " 


Strawberries 


0.80 " 


Gooseberries 


0.82 " 


Plums 


0.85 " 


Raspberries . 


0.88 " 


Whortleberries 


1.08 " 


Mulberries . 


1.29 " 


Currants 



1.42 p. c. 
1.52 " 
1.57 " 
1.63 " 
1.72 " 
1.80 " 
1.88 " 
2.02 " 

2.43 " 



FRUITS AND THEIR COMPOSITION. 309 

Tables V. and VI. represent the proportion in which the solu- 
ble constituents of the fruits are found in the juice or must ob- 
tained from them ; in the practical execution of the fabrication of 
fruit wines we will have occasion to refer to these tables. 

For the preparation of wine only the soluble substances, which 
pass into the must and from which the wine is formed, are chiefly 
of interest, and it will be necessary to consider them somewhat 
more closely. 

Grape-sugar or glucose. This sugar is widely diffused through- 
out the vegetable kingdom, occurring in most kinds of sweet fruits, 
in honey, etc. Artificially it can be readily obtained by heating a 
solution of cane sugar with a dilute acid ; it is also formed by 
dissolving cane sugar in wine. On a large scale it is prepared 
by boiling starch with very dilute sulphuric acid for several 
hours, neutralizing the liquid with chalk and evaporating the 
solution. 

Grape-sugar is much less sweet than cane-sugar ; in alcohol of 
90 per Tr. it is sparingly soluble ; in hot water it dissolves in 
every proportion; of cold water it requires, however, about 1J 
parts for solution. It crystallizes from an aqueous solution with 
one molecule of water in cauliflower-like masses and from hot 
alcohol in warty, anhydrous needles. A solution of crystallized 
grape-sugar turns the plane of polarization to the right, but one 
of anhydrous grape-sugar to the left. 

Acids. The acid reaction of fruit juices is partly due to 
malic acid and partly to citric acid, and also, as in the case of 
grapes, to tartaric acid. As a rule all these acids are present ; in 
currants citric acid predominates; in apples, etc., malic acid. 

The presence of potassium in grape-must gives rise to the for- 
mation of potassium bitartrate or crude tartar. Tartar requires 
for its solution 240 parts of cold water; in alcoholic fluids it is less 
soluble, and hence it is found as a crystalline deposit in wine 
casks. Fruit-musts contain no tartaric acid, and, consequently, 
the wines prepared from them cannot deposit tartar. The salts 
formed by malic and citric acids with potassium being readily 
soluble and even deliquescent form no deposit in the wine. 

Albuminous substances. By this general term are designated 
several nitrogenous vegetable substances which have the same 



310 VINEGAR, CIDER, AND FRUIT-WINES. 

composition ; they are vegetable albumen, fibrin, and glue. The 
quantities of these substances in the different musts are, on the 
one hand, too small, and the difficulty of accurately distinguishing 
them from each other is, on the other, so great that it is scarcely 
possible to definitely determine the kind present in the fruit juice ; 
most likely all three are present at the same time. 

For the preparation of wine these bodies are of importance ; 
they furnish the material for the development of the yeast-fungus 
during fermentation. 

Pedous substances. In the paragraph " ripening of fruits," the 
pectous substances have been sufficiently discussed; they are 
scarcely ever wanting in a fruit juice, but being insoluble in alco- 
holic fluids they are entirely separated with the yeast, and hence 
are not present in fruit-wines. 

Gum and vegetable mucilage. Our knowledge as regards gum 
is still limited. Gum-arabic, which may be studied as a repre- 
sentative of this class, is an exudation from certain species of 
acacia and consists essentially of arabin. It is generally supposed 
to be soluble in water, but on endeavoring to filter a somewhat 
concentrated solution not a drop will be found to run off, and the 
little which possibly may pass through the filter is by no means 
clear. 

Closely related to gum-arabic is bassorine, the gum which 
exudes from the cherry, plum, almond, and apricot trees. It 
does not give a slime with water, but merely swells up to a 
gelatinous mass. 

Wine brought in contact with the smallest quantity of gum- 
arabic remains permanently turbid and cannot be clarified by 
filtering or long standing. From this behavior of gum it may 
be concluded that, though it may occur dissolved in the must, it is 
not present in the wine. 

The various kinds of vegetable mucilage have also not yet 
been accurately examined; it is only known that there are 
quite a number of them. It is, however, likely that only a 
few of them are actually soluble in water. Though the muci- 
lage ^df certain seeds, such as linseed and quince-seed, may be 
considered as readily soluble in water as gum-arabic, and perhaps 
more so, because it is a perfectly clear fluid drawing threads, 



FRUITS AND THEIR COMPOSITION. 311 

yet on filtering it will be found that what passes through above 
contains scarcely a trace of a mucilaginous substance. Hence, 
it is doubtful whether mucilages exist which are actually solu- 
ble in water, and whether they occur in wine. Artificial dex- 
trin is, however, an exception, as it forms with water a perfectly 
clear fluid, which can be filtered. We will here call attention to 
an easy method of distinguishing between solution of gum- 
arabic and of dextrin ; the first cannot be heated, even for a 
minute, over an open fire without scorching, while the latter can 
be completely boiled down without fear of burning. 

Tannin. Several kinds of tannin occur in plants, which can ; how- 
ever, be finally reduced to two modifications, viz : pathological and 
physiological tannin. The first occurs in large quantity in nut- 
galls, especially in the Chinese variety, also in sumach (the twigs 
of Rhus Coraria) and in many other plants. Pathological tan- 
nin is characterized by splitting under the influence of dilute 
acids as well as by fermentation into gallic acid and grape-sugar. 
Furthermore, it completely precipitates glue from its solutions, but 
is not suitable for the conversion of the animal skin into techni- 
cally serviceable leather which will withstand putrefaction. Be- 
sides, only the gallic acid obtained from pathological tannin 
yields pyrogallic acid by dry distillation. 

Physiological tannin is chiefly found in materials used for tan- 
ning ; it cannot be split by dilute acids or fermentation, does not 
yield gallic acid, and the product of dry distillation is not pyro- 
gallic acid, but pyrocatechin or oxyphenic acid ; it converts the 
animal skin into perfect leather. 

There can be but little doubt that physiological tannin is the 
variety found in fruits or fruit-juices. Generally speaking, a 
content of tannin in wine is not exactly a desirable feature, as 
it is readily decomposed. It can only have an advantageous 
effect when the wine contains an excess of albuminous substances 
which the tannin removes by entering into insoluble combinations 
with them. This may be the reason why wine containing tannin 
is considered more durable, because if it contained albuminous sub- 
stances in large quantity it would be still more readily subjected 
to changes. Under such circumstances a small addition of tan- 
nin to the wine may be of advantage, though instead of tannin it 



312 VINEGAR, CIDER, AND FRUIT-WINES. 

is advisable to use an alcoholic extract of grape-stones, which are 
uncommonly rich in tannin. 

Inorganic constituents. The inorganic constituents of the dif- 
ferent varieties of fruit are very likely the same, namely, potash, 
lime, magnesia, sulphuric and phosphoric acids; they vary only 
in the proportions towards one another and in the total quantity 
of all the substances. Moreover, their quantity is too small to 
exert an influence upon the quantity of the wine to be produced, 
being of interest only in regard to the exhaustion of the soil. 
Though lime and sulphuric acid in sufficient quantity occur 
almost everywhere in the soil, this cannot be said of potash and 
phosphoric acid. Unfortunately there are no accurate statements 
regarding the amount of these substances which is withdrawn 
from the soil by the crop of one year, but there can be no doubt 
that it is very large, and that consequently fruit-trees from time to 
time require a certain amount of manure in order to return to the 
soil what has been taken from it. 

Fermentation. Fermentation is a chemical process which is 
always caused by the presence of a ferment or a substance in a 
peculiar state of decomposition. Although to induce fermentation 
the presence of a ferment is necessary, it does not take part in the 
decomposition of the fermenting substance. The products of fer- 
mentation vary according to the nature of the fermenting body, 
as well as according to the nature of the ferment. Each peculiar 
kind of fermentation requires a certain temperature, and it is 
nearly always accompanied by the development of certain living 
bodies (infusoria or fungi). 

When yeast is added to a dilute solution of dextrose or another 
glucose, vinous fermentation speedily sets in; whilst a solution of 
cane-sugar undergoes fermentation but slowly, the cause being 
that this sugar must first be converted into inverted sugar before 
fermentation can commence. Vinous fermentation proceeds most 
rapidly at 77 to 86 F., and does not take place below 32 or 
above 95 F. The presence of a large quantity of acids or alkalies 
prevents fermentation, while if the liquid has a faint acid reaction, 
fermentation proceeds best. 

The yeast which is formed in the fermentation of the juice of 
grape and other kinds of fruit is produced from soluble albuminous 



FRUITS AND THEIR COMPOSITION. 313 

bodies contained in fruit. It consists of one of the lowest members 
of the vegetable kingdom (Torula cerevisice), and under the micro- 
scope is seen to be made up of little oval transparent globules, 
having a diameter of not more than 0.1 millimetre and often 
adhering in clusters and strings. They are propagated by bud- 
ding, and die as soon as they have reached their highest state 
of development. In contact with air and water yeast soon un- 
dergoes putrefaction. 

The chief products of vinous fermentation are alcohol and car- 
bon dioxide ; a small quantity of sugar is at the same time con- 
verted into other products, about 2.5 per cent, being transformed 
into glycerin and 0.6 to 0.7 per cent, into succinic acid. A 
further portion of the sugar, about one per cent., is assimilated in 
the form of cellulose by the yeast and separated. By the simul- 
taneous formation of these different secondary products about 
5.5 to 6.5 per cent, of sugar is lost in the formation of alcohol. 
As they are not always formed in equally large quantity no con- 
clusion can be arrived at from the content of sugar in the must as 
to the quantity of alcohol corresponding to theory in the finished 
wine ; it is, as a rule, supposed that the sugar yields one : half its 
weight of alcohol, which is sufficiently correct for all practical pur- 
poses. 

Absolute alcohol, L e., alcohol entirely free from water, is a very 
mobile fluid, clear as water and almost odorless ; it boils at 173 F., 
and when it is cooled down to 148 F. it becomes viscid, but 
does not solidify. Its specific gravity at 32 F. is 0.80625, and 
at 59 F. 0.79367. It is very inflammable, and burns with a 
blue, non-luminous flame. It absorbs moisture with great avidity, 
and is miscible with water in all proportions, the mixture evolv- 
ing heat and undergoing contraction. 

The methods for determining the content of alcohol in a fluid 
have already been given on p. 198. 

Succinic acid. No accurate researches have as yet been made 
in regard to the quantity of this acid in wine, its influence upon 
the quality of the wine, and the conditions under which more or 
less of it is formed during fermentation. According to Pasteur, 
the more succinic acid is formed the slower fermentation pro- 
gresses; the weaker the development of yeast and the less nour- 



314 VINEGAR, CIDER, AND FRUIT- WINES. 

ishment offered to the latter. In acid fluid more succinic acid is 
formed than in neutral. 

Succinic acid is quite readily soluble in a mixture of alcohol 
and water, and consequently also in wine ; its taste is not very sour, 
but disagreeable, and adheres for some time to the tongue ; hence 
its presence can scarcely be expected to give an agreeable taste to 
the wine. 

Glycerin. Glycerin being found in grape-wines, in which it is 
formed from the sugar by fermentation, there can scarcely be any 
doubt of its formation under the same conditions in fruit-wines. 
According to Pasteur, the quantity of glycerin in wine is in a 
definite proportion to the succinic acid formed, and, hence, more 
glycerin would be produced with slow fermentation and in an acid 
fluid. In red wines Pasteur found 4 to 7 per cent, of glycerin. 

Pure glycerin is a colorless, very viscid liquid having a specific 
gravity of 1.27. It can be mixed with water and alcohol in all 
proportions and possesses a very sweet taste. It is very likely 
that the mild sweet taste of many ripe wines is due to a certain 
content of glycerin. 

A solution of 7 parts of glycerin in 1000 of water (the pro- 
portion in which Pasteur found glycerin in wine) does not possess 
a sweet taste and differs from water only in being more insipid. 
By adding to such a solution 100 parts of alcohol the mixture 
shows a taste different from that of alcohol alone diluted in the 
same proportion, the predominant taste of the latter being de- 
creased by the glycerin and that of the mixture becoming milder. 
Hence a certain importance has to be ascribed to the glycerin. 

Carbonic acid. The greater portion of the carbonic acid formed 
by fermentation escapes as a gaseous body during the process, but 
a certain portion remains dissolved in the wine as long as the tem- 
perature of the latter is not raised. The temperature of cellars 
generally increases, however, towards the end of spring, which 
causes anew a slight development of carbonic acid in consequence 
of which the wine again becomes turbid. The presence of car- 
bonic acid is of advantage only in young wine, as it protects it 
from the direct action of the air by forming a layer upon the 
surface; in old wines it conceals, however, the fine aroma and 
taste, making them appear younger than they actually are. 



FRUITS AND THEIR COMPOSITION. 315 

Though it cannot be said that carbonic acid plays an essential 
part in the preparation of wine, it deserves attention on account 
of its deleterious influence upon the workmen. To avoid all 
injurious consequences provision should be made for a thorough 
ventilation of the cellar by means of windows and doors. If 
fermentation is carried on in barrels, the carbonic acid developed 
in a number of them should be conducted by means of tubes 
secured air-tight in the bungs to a zinc-pipe which passes through 
a suitable aperture into the open air. 

How large the quantity of carbonic acid is which is developed 
during the fermentation of a barrel holding 1200 liters of must 
at 10 per cent. = 240 kilogrammes of sugar is shown by the 
following calculation : 180 grammes of grape-sugar yield 88 
grammes of carbonic acid at 32 F. 1 gramme of carbonic acid 
occupies a volume of 0.50848 liter, which, with a cellar tempera- 
ture of 50 F., corresponds to 0.527294 liter. Hence we have 
for the calculation of the total quantity of carbonic acid developed 
88 x 0.527294 X 4000* or ^ much ag 



o 

the contents of 52 barrels containing each 1200 liters. 

Alkaloid in wine. It has been frequently asserted that an alka- 
loid exists in young wine, which not being contained in the must 
or the yeast must have been formed from the nitrogenous consti- 
tuents of the yeast or of the fluid during fermentation. It has 
not been found in old wine, and it is therefore concluded that it 
in time decomposes. Should this observation be confirmed, it 
would explain the difference in the effects of the very intoxicating 
young wines and of old wines. 



reduced 



316 VINEGAR, CIDER, AND FRUIT- WINES. 



CHAPTER XXVI. 

PRACTICE OF THE PREPARATION OF CIDER AND FRUIT- 
WINES. 

THE first step in the preparation of fruit-wines is the gaining 
of the juice or must from the fruit. Stamping or grinding and 
subsequent expressing of the paste thus formed by means of strong 
pressure suffice in most cases for berries and other small fruits. 
With apples, etc., this manner of reduction is not only difficult, 
but also connected with considerable loss caused by larger and 
smaller pieces jumping from the trough. 

The earliest appliance known was simply a trough in which 
the apples were reduced to an imperfect pomace by rolling them 
with a heavy cylindrical stone or by pounding them as in a 
mortar. An improvement was the production of the English 
cider-mill. This consisted of a pair of coarsely corrugated iron 
cylinders from which the apples fell to a second pair close together 
and finer in their surfaces and passed through finely mashed to 
the pomace vessel underneath. In 1852, Mr. W. O. Hickock, of 
Harrisburg, Pa., invented a portable cider-mill which consisted of 
a pair of small horizontal cylinders armed with small spirally 
arranged teeth or spikes revolving close together, one at a higher 
velocity than the other. The apples were first broken by the 
action of a coarsely-fluted roller which revolved against a table 
under the hopper, and after passing between the cylinders the 
apples were not only bruised but also grated into the required 
pomace. This machine was capable of grinding 100 bushels of 
apples per day. Numerous modifications have been made in the 
plan of Mr. Hickock's mill, some being simply spiked cylinders 
against which the apples were carried and held till grated by 
reciprocating plungers. 

Our limits will not permit us to notice all the various styles 
of portable mills before the public or the multitude of graters or 



PREPARATION OF CIDER AND FRUIT-WINES. 



317 



apple-grinders, many of which possess excellent points and are 
worthy of commendation. An excellent apparatus for crushing 
apples is the crushing-mill shown in Figs. 66 and 67, B C (Fig. 
67) representing the cylinders provided with teeth. A hopper, A, 
receives the apples, which pass between the cylinders, where they 
are crushed and fall into the receiver F placed underneath. Two 



Fig. 66. 



Fig. 67. 





men operate this mill by means of cranks. Larger and stronger 
mills are used when the quality of apples seems to require them, 
and in that case horse-power is applied. 

Fig. 68 shows Davis's star apple-grinder, several sizes of which 
are manufactured by the G. H. Bushnell Co., of Thompsonville, 
Conn. The grinder shown in the illustration is a heavy machine 
weighing 340 Ibs. The cylinder is 12 inches in diameter and 12 
inches long, is turned and carefully balanced, has grooves planed 
in to receive the knives, six in number, which are finely made 
and tempered. Each knife furnished is made of steel-plated iron, 
the steel being very thin and having a back of iron ; there is no 
danger of breaking, although made very hard. The end of the 
cylinder is banded with wrought-iron bands and the knives are 
set with set-screws. The shaft is of steel and runs in anti-friction 
metal. The concaves are hung at top, so they can swing back at the 
bottom to allow stone, pieces of iron, etc. to pass through without 
injuring the knives. The concaves are held to their place by a 



318 VINEGAR, CIDER, AND FRUIT-WINES. 

holt which allows the concave to be set as close as desired to the 
cylinder, and is held to its place by coil-springs which will give 
enough to allow stones to pass and yet hold rigid in grinding 
even frozen apples. The frame is one casting, and as the concaves 
are fast to the frame they cannot get out of line or be displaced, as 
is the case when the concave is fast to the hopper. The hopper 



Fig. 68. 




can be readily removed to adjust knives and all parts are adjust- 
able and easy to get at. This machine can be gauged to grind 
from 200 to 400 bushels per hour. Power required to grind six 
bushels per minute about six horse-power or about as many horse- 
power as desired to grind bushels per minute. 

Presses. For obtaining the juice from berries, etc. a press is 
generally not required, or at least only a slight pressure ; the 
greater portion of it runs out from the must by placing the latter 
upon a cloth spread over a perforated bottom in a vat. The juice 
retained by the lees, which is, as a rule, very sour and has to be 
diluted with water, can be extracted with the latter more completely 
than is possible with the strongest press. 

For obtaining the juice from apple pomace, etc. a good press 
is, however, an important auxiliary. Before the introduction of 
screws the method of extracting the juice of the apple was by 
the use of heavy weights, wedges, and leverage. Until within a 
late period a large wooden screw was used and is even now T 
employed in some sections of the country. Of these screws two 



PREPARATION OF CIDER AND FRUIT-WINES. 



319 



Fig. 69. 



and frequently three and four, set in a strong frame-work of 
double timbers, were found no more than sufficient to separate the 
cider from the pomace. In order to operate these screws a long 
heavy wooden lever became necessary, which required the united 
services, of four or five men to handle, and not ^infrequently the 
strength of a yoke of oxen was called into requisition before the 
work could be accomplished. An improvement upon the wooden 
screw was made by the substitution of the iron screw and iron 
nut. But the objectionable feature 
of having to handle heavy and 
cumbersome levers still remained, 
making labor irksome and ex- 
pensive. In modern presses this 
difficulty has been entirely over- 
come, and the juice is extracted 
from the pomace with great ease 
and completeness. 

Of the many presses before the 
public we illustrate a hand-press 
and a power-press manufactured 
by the G. H. Bushnell Co., of 
Thompsonville, Conn., the same 
concern furnishing presses of all 
sizes between these two. Fig. 69 

shows the " Farmer's cider-press." It is 7 feet 1 inch high with 
a width between the rods of 3 feet If inches. It will hold 15 to 
16 bushels of apples at a pressing and is especially designed for 
individual use. It is also admirably adapted for squeezing the 
juice from small fruits, berries, etc. 

Fig. 70 shows the " Extra power cider-press," with revolving 
platform. It is 13 feet 4 inches high, 6 feet 4 inches wide be- 
tween the rods, and has a platform 13 feet 3 inches long. It 
gives a pressure of 250 tons. The press is always loaded in one 
place, and consequently the grater can be located immediately 
over the middle of the cheese, avoiding the necessity of convey- 
ing the pomace from one end of the press to the other. This 
press can easily make a pressing of 12 barrels of cider each hour. 




320 VINEGAR, CIDER, AND FRUIT-WINES. 

Fig. 71 shows the revolving platform belonging to the above 
press, for which the manufacturers claim the following ad van- 
Fig. 70. 




tages : 1. Both ends of the platform are loaded and unloaded in 
the same place. 2. It is so geared that one man can easily and 
quickly revolve it. 3. The grinder can be directly over the 
centre of the cheese, thus avoiding all the labor of shovelling the 
pomace. 4. The pomace being dropped in the centre of the 
cheese, it is an easy matter to spread it with equal density over 
the entire surface, thus building a cheese that is not liable to tilt 
or slide. The cider runs into a copper basin in the centre of the 
platform between the two cheeses. The basin is so arranged that 
it receives the cider while the platform is being revolved as well 
as while the press is working. 



PREPARATION OF CIDER AND FRUIT-WINES. 321 

A is the copper basin to receive the cider from platforms, and 
has an outlet through the bottom, about 6 inches in diameter, 
for the cider to pass off into the tank below. B is a copper tube 




encasing the rods. (7, (7, C, C are four posts fastened to the plat- 
form to hold guide-pieces for racks. D, D are rack guides. 

Ferguson's improved racks. The single racks are made of some 
light and tough wood bass-wood or spruce seems best cut into 
strips about \ x J inch and placed about \ inch apart, with four ? 
five, or more elm strips, 2 inches wide and about f inch thick, 
placed across and nailed to the narrow slats. The 2-inch slats 
extend beyond the narrow ones on each side about 4 inches. 
This is to support the wings, which are fastened to the rack by 
3 or more bronze hinges. These wings, with the aid of 2 re- 
taining bars, make the box to form the pomace in. The slats 
are rounded on the edges so as not to injure the press-cloth. 
Steel wire nails or wire staples are used of sufficient length to 
clinch. 

Double racks are made by using slats j^-x-J- inch. The slats 
on one side are laid directly across the slats on the other side. 
.Four wide slats are put at the outer edges, then these are all fast- 
ened together by steel wire nails or staples. These racks have 
the advantage of having an even surface on each side. The 
press-cloth will last much longer than when used on single racks, 
where it is strained over 4 to 9 elm slats. 

To lay up a cheese with the Ferguson improved rack, com- 
mence on the platform of the press and lay a rack ; then turn up 
21 



322 VINEGAR, CIDER, AND FRUIT-WINES. 

the wings on each side of the rack and place the retaining bars 
on each end, with the hooks on the outside of the wings, so as to 
hold them up. Over this box spread the cloth, fill the box evenly 
full of pomace, then turn in the sides and ends of the cloth over 
the pomace, the cloth being of sufficient size to cover it. The re- 
taining bars are then removed, allowing the wings to fall in 
place. Another rack is placed on the cheese just made, the re- 
taining bars placed in position to hold up the wings, another 
cloth placed on the box, etc., and this operation is continued 
until there is the right number of layers in the press. A rack 
should be placed on the top of the last layer. A guide should be 
used in laying up the cheese, so as to bring each rack directly 
above the other. 

Plain racks. These are made, either single or double, of slats 
of the same description and dimensions as are used in the Fer- 
guson racks, but in the place of wings and retaining bars, a form 
square in size and 4 inches deep is used to form the sides of a 
box for the pomace. In laying up a cheese commence by placing 
a rack on the platform, and upon this place the form, spread a 
cloth over the form and fill even up with pomace ; then fold the 
ends and sides of the cloth over on to the pomace, as described 
with the other style of rack, and remove the form. Place an- 
other rack on the layer just formed, and put the form on that 
and proceed as before until the cheese is complete. It will re- 
quire one cloth less than the number of racks used for a cheese. 
Care must be exercised in laying a cheese to have the racks come 
evenly, as they are liable to tilt if they overhang. The best way 
to avoid the liability to slide or tilt is to lay the racks alternately 
the length and breadth of the press. 

Fig. 72 shows Willson's telegraph wine and cider mill. The 
upper roller is furnished with sharp projecting ribs, which cut 
the apples into pieces sufficiently small to be readily received be- 
tween the lower rollers. The two lower crushing rollers are cast 
with ribs and grooves, and these draw in the pieces prepared 
by the upper roller, and by this means the fruit is thoroughly 
mashed between the smooth segments, which breaks all the cells 
of the apples and makes the subsequent labor of pressing much 



PREPARATION OF CIDER AND FRUIT-WINES. 323 

easier ; and should the pomace be allowed to stand a short time a 
large portion of the cider will run off without pressing. Both 
the upper and lower rollers are adjustable, and can be set to mash 
grapes for wine without breaking the seeds. It is peculiarly 
adapted to grinding the wine plant, mashing it without sepa- 

Fig. 72. 




rating the fibre. The hopper is adjustable, and can be removed 
in an instant for cleaning the mill. The follower is brought up 
out of the tub by simply raising the screw. Several sizes of this 
mill are manufactured. 

In the equipment of a first-class modern cider mill nothing gives 
better satisfaction for the money expended than an apple ele- 
vator. The expense is a small matter compared with the con- 
venience of having the mill so arranged that apples may be 
brought from any part by a perfect working elevator and carrier. 
Fig. 73 shows a section of an elevator manufactured by the G. 
H. Bushnell Company, of Thompsonville, Connecticut. The 
chain runs over and is operated by a sprocket gear at the head 
with fast and loose pulleys. The scrapers are of wood, 3 inches 



324 VINEGAR, CIDER, AND FRUIT- WINES. 

wide and 11 J inches long, bolted to lugs or projections on the 
chain. When run at from 50 to 70 revolutions per minute it 



Fig. 73. 




will elevate from 5 to 10 bushels per minute. It works at an 
inclination or carries on a level. 

Testing the Must as to its Content of Acid and Sugar. 

With the exception of the grape but few varieties of fruit con- 
tain acid and sugar in such proportion and in such quantity 
(generally too much acid and too little sugar) as that the must 
obtained from them will yield, when subjected to fermentation, a 
drinkable and durable wine. Wine whose content of acid ex- 
ceeds 1 per cent, is too sour to the taste, and one containing less 
than 5 per cent, of alcohol cannot be kept for a long time. Now 
as all fruit wines may be called artificial wines, and a natural 
product has consequently to be improved in order to make it 
more agreeable and wholesome, it is necessary to find ways and 
means by which the object can be accomplished in a manner 
most conformable to nature. For this purpose a knowledge of 
the content of acid and sugar in the fruit-must is required. 

To find the quantity of acid, compound a determined quantity, 
about 50 cubic centimetres, of must with about 5 grammes of 



PREPARATION OF CIDER AND FRUIT-WINES. 325 

purified animal charcoal,* boil the mixture about five minutes, 
and after cooling replace the exact quantity of water lost by 
evaporation. After shaking bring the whole upon a coarse 
paper, filter in a glass funnel, and let it run off. Of the clear 
and generally colorless filtrate bring 6.7 cubic centimetres into a 
small beaker, add sufficient distilled water to form a layer of 
fluid 2 to 3 centimetres deep, and color red with 5 to 10 drops of 
litmus tincture. While holding the beaker in the left hand and 
constantly moving it slowly in a horizontal direction alloAV to 
run or drop in from a pipette graduated in ^ cubic centimetres 
and filled to the O mark, decinormal liquid ammonia until 
the last drop no longer changes the color of the fluid and the 
place where the drop falls appears as if made clear by a drop of 
water. Now prevent a further flow of the ammonia by closing 
the pipette with the index finger of the right hand, and read off 
the quantity of ammonia consumed. The must examined con- 
tains as many thousandths of malic acid as cubic centimetres of 
liquid ammonia were required to color the fluid blue. 

Now if the examination shows that a must contains more than 
8 parts of acid per thousand, it is evidently too sour for the 
preparation of a palatable and wholesome fruit wine, and hence 
must be diluted to such degree as to reduce the content of acid to 
6 or at the utmost to 8 parts per thousand. The calculation for 
this dilution is very simple, and consists in multiplying the acid 
per thousand parts present by 100 and dividing with the content 
of acid the wine is to have, the entire volume containing the de- 
sired acid per thousand being thus obtained. If, for instance, 18 
parts per thousand of acid have been found in currant-must and 

-j rj/"i vIS 

the wine is only to show 6J parts per thousand, then 

= 276.923, in round numbers == 277, i. e., 277 parts by measure 
of water have to be added to every 100 parts by measure of 
must. 

The content of acid in the must thus forms the initial point 
for the dilution in order to obtain, after fermentation, wine with 

* Bone-black which is first boiled with solution of sodium carbonate for 
some time, and then after washing and extracting with hydrochloric acid is 
again washed and dried. 



326 VINEGAR, CIDER, AND FRUIT-WINES. 

a determined quantity of acid. To be sure the content of acid is 
sometimes increased by fermentation, some succinic acid, as pre- 
viously mentioned, being formed and perhaps also some acetic 
acid ; sometimes, however, the content of acid decreases, which is 
very likely partially due to the water used for the dilution of the 
must containing earthy carbonates (lime, magnesia). It is, there- 
fore, best not to have too much acid in the must, since, if the 
finished wine should be lacking in acid, it can be readily reme- 
died by a suitable addition of tartaric acid, which is, however, 
not the case when it contains too much free acid. 

The determination of the sugar in must is less difficult and has 
already been fully described on p. 197, hence there remains only 
the question how much sugar has to be added to the must in 
order to obtain a durable wine. 

Numerous analyses have shown that there is scarcely any 
grape-wine which contains less than 7 per cent, by weight of 
alcohol, while in more generous wines the content rises to 12 per 
cent, and more. Fruit-wines in order to possess good keeping 
properties should never show less than 7 per cent, by weight of 
alcohol, but there is no reason why they should not contain as 
much as 10 per cent. The advantage of the latter content is 
evident, the wines being thereby almost absolutely protected from 
spoiling while they improve in aroma and taste, the various kinds 
of ether being only formed in wine rich in alcohol. 

The manner of calculating the quantity of sugar which has to 
be added to the must to give the wine the desired content of 
alcohol will be best shown by the following example : Suppose 
135 liters of must which contains 4 per cent, of sugar are to be 
changed into must with 15 per cent, of sugar. 

For this purpose deduct from the weight of the must (which 
for the sake of simplicity we will consider equal to its volume) the 
weight of the sugar contained therein, multiply by the difference 
the per cent, of sugar the must is to contain, divide the product 
by 100 less the per cent, of sugar and deduct from the quotient 
the per cent, of sugar already present in the must. For instance : 
135 liters of must with 4 per cent, of sugar are to be changed 
into must with 15 per cent, of sugar. In 135 liters are contained 
5.4 kilogrammes of sugar, 1355.4 = 129.6, which multiplied by 



PREPARATION OF CIDER AND FRUIT-WIXES. 327 

15 1944 ; this number divided by 100 15 = 85 gives 22.87. 
Deduct from this 5.4, and there remain 17.47 kilogrammes of 
sugar which have to be added to the must to give it 15 per cent, 
of sugar. 

For 325 liters of must with 3J per cent, of sugar to be changed 
into must with 20 per cent, of sugar the calculation Avould be as 
follows : 

(325 11.375)20 ^ 313.625 x 20 _ 
10020 80 

o-| q #9 re 

p 1 = 78.406 11.375 = 67.03 kilogrammes of sugar to 

be added. 

600 liters of must with 6 per cent, of sugar are to be changed 

into must with 22 per cent, of sugar : : X U 36 = 117.4 

O\J 

kilogrammes of sugar. 

The above examples will suffice to enable any one to execute 
the calculations as required. 

The above calculations are based upon pure, anhydrous grape 
sugar, an article which does not exist in commerce, and hence has 
to be replaced either by commercial grape-sugar (glucose) or cane- 
sugar. Glucose, however, containing as a rule only 67 per cent, 
of anhydrous grape-sugar, 1J times the quantity calculated above 
must be used, thus in the last example 176 kilogrammes instead of 
117.4. With cane-sugar the proportion is the reverse, 171 parts 
by weight of cane-sugar being equal to 180 parts by weight of 
anhydrous grape-sugar ; hence the per cent, of anhydrous grape- 
sugar calculated according to the above method must be multi- 
plied by the fraction -j-|- T or the factor 0.95. According to this, 
instead of the 117.4 kilogrammes of grape-sugar in the last 
example, 111.73 kilogrammes of cane-sugar will have to be used. 

Glucose. Pure glucose being identical with the sugar in sweet 
fruits its use for sweetening fruit-juices intended for the prepara- 
tion of wine is perfectly justifiable. With the dispute still carried 
on with honest weapons, whether it is permissible to assist nature 
with glucose when it fails to succeed in its labor of forming sugar 
in abundance, we have here nothing to do, since we know that 
the principal product alcohol or spirits of wine and almost the 



328 VINEGAR, CIDER, AND FRUIT-WINES. 

only one which passes into the wine by the fermentation of sugar, 
possesses the same properties whether it is formed from fruit-sugar 
or from glucose, and that neither one nor the other can be injurious 
to health in the state of dilution in which it presents itself in the 
wine, provided the latter be used in moderation. The must might 
be sweetened, as is frequently done, with cane-sugar which occurs 
in sugar-cane, in beet-root, in sugar-maple, etc. But with the use 
of glucose we are one step in advance, since cane-sugar before 
fermenting is first resolved into a mixture of dextrose (glucose) 
and levulose. 

Commercial glucose is never pure, as it contains, besides about 
15 per cent, of water, of which about 6 per cent, is water of 
crystallization, about 1 8 per cent, of dextrin or similar substances, 
and some gypsum. It has a white color and is found in commerce 
packed in boxes into which it is poured while in a fluid state 
and gradually congeals to a hard mass. It is odorless and has a 
faint sweet taste. On heating it becomes smeary and finally 
melts to a yellowish syrup. Its content of anhydrous fruit- 
sugar varies between 62 and 67 per cent. Inferior qualities con- 
tain either less sugar or have a more or less dark color and a 
disagreeable odor and taste. Independently of the content of 
sugar, glucose to be suitable for the preparation of wine should 
show no odor or by-taste. 

The accurate determination of the content of pure sugar in 
glucose is connected with some difficulty. But few manufacturers 
are provided with the necessary materials for making the analysis 
with Fehling's solution, and besides a certain amount of skill is 
required for obtaining accurate results by chemical tests. In 
consideration of this, Anthon of Prague has devised tables which 
are^ based upon the varying specific gravity of different saturated 
solutions of glucose, or rather upon its solubility in water. While 
1 part of anhydrous grape-sugar requires for its solution 1.224 
parts of water at 53.6 F., the foreign admixtures accompanying 
it dissolve in every proportion in water. Hence a saturated 
solution of glucose will show a greater specific gravity the more 
foreign substances it contains. In Authon's tables is found the 
specific gravity and from this the content of anhydrous grape- 
sugar or glucose in the solution. In preparing a solution of 



CIDER FROM APPLES AND PEARS. 



329 



starch-sugar for examination care must be had that it is completely 
saturated. Heat must not be used for eifecting the solution, but 
a certain quantity of the glucose to be examined is rubbed in a 
mortar with one-half its weight of water at 53.6 F., and after 
pouring the thickish, turbid fluid into a tall beaker it is allowed 
to stand until clear. Anthon's table is as follows : 



Specific gravity 




Specific gravity 




of the solution 




of the solution 




saturated at 


Contains of foreign 


saturated at 


Contains of foreign 


53.6 F. 


substances. 


53.6 F. 


substances. 


1.2066 


per cent. 


1.2522 


25 per cent. 


1.2115 


2.5 " 


1.2555 


27.5 ' " 


1.2169 


5.0 " 


1.2587 


30.0 " 


1.2218 


7.5 " 


1.2631 


32.5 " 


1.2267 


10.0 " 


1.2665 


35.0 " 


1.2309 


12.5 " 


1.2703 


37.5 " 


1.2350 


15.0 " 


1.2740 


40.0 " 


1.2395 


17.5 " 


1.2778 


42.5 " 


1.2439 


20.0 " 


1.2815 


45.0 " 


1.2461 


22.5 " 







CHAPTER XXVII. 

CIDER FROM APPLES AND PEARS. 

Cider from apples. The expressed juice of well-selected apples, 
properly prepared, forms a lively, sparkling liquor far superior to 
many wines. It is quite a favorite article of home production, 
nearly every farmer in regions where apples are grown making 
his barrel of cider for use through the winter, but a large amount 
finds its way into the city markets. A considerable quantity is 
also consumed in the shape of bottled cider, " champagne cider," 
" sparkling cider," and similar substances for, or imitations of, 
champagne wines; large quantities of this clarified cider being 
produced in some parts of the country, notably New Jersey. 
Most of the cheaper kinds of champagne (American champagne) 
are made in this way. 

In England and France considerable quantities of cider find 



330 



VINEGAR, CIDER, AND FRUIT-WINES. 



their way into the markets, though it is there, as here, largely an 
article of home consumption. Certain parts of those countries 
are famous for the quality of their ciders, notably Normandy, in 
France, and Herefordshire and Devonshire, in England. France 
produced in 1883, 23,493,000 hectoliters (620,211,200 gallons) of 
cider, or one-half of the quantity of wine produced or three times 
as much as the total quantity of malt liquors. 

Rousseau has published the mean of twenty analyses of Brit- 
tany cider, but his results are so low that it is thought by French 
authorities that his samples had been watered : 



Alcohol, per cent, by volume 
Extract grammes per liter . 
Sugar .... 

Total ash .... 
Ash soluble in water 



2.5 
19.3 
2.5 
1.52 
1.17 



The following are analyses of pure ciders from different parts 
of France made in the Paris municipal laboratory ; the figures 
are in grammes per liter : 





- 







T 


0) 

1 






o 




c 3 


^ ** 




t-- 


be . 




cc 


SB 




r- * 


c > 




PH 


- o 




06 


i % 




c5 


^>H 




u - 


u'0> 


d 


*3 


,00 

- r-i 'A 




o a 


0> - 
















2C 

'3 * 




13 


2 o 

O> 


5 <B" 


o 
fe 


*. 


'. S^ ? 




0-3 


- a 


2 




s'S 


13 


2 


|1 




^ 


PH 


o 


PH 


PH 


5 


5 


DH 


Alcohol, in weight, per 


















liter .... 47.40 


41.08 


37.92 


34.76 


23.70 


7.90 


25.30 


19.75 


Extract dried at 212 F. ; 57.60 


30.90 


20.90 


61.30 


53.20 


69.70 


81.20 


'63.80 


Extract dried in vacua 


60.10 


37.60 


27.00 


72.70 


60.80 


82.00 


92.60 75.00 


Total ash 


3.50 


2.50 


2.50 


3.00 


2.60 


2.54 


2.30 


2.80 


Analysis of the Ash. 


















Phosphates insoluble in 


















water .... 
Carbonate of potash 
Other alkaline salts 


0.38 
2.23 
0.89 





0.25 
1.40 
0.85 


0.30 
2.00 
0.70 


0.45 
1.80 
0.35 


0.62 
1.51 
0.41 


0.17 


20.55 


Reducing sugar 
Acidity expressed as 


20.00 


7.50 


4.40 


3.70 


16.50 


36.00 


39.00 


25.00 


H 2 S0 4 
Acidity of the cider dried 


3.60 


4.07 


5.36 


4.54 


3.23 


2.68 





2.08 


in vacua . . . 


2.50 


2.40 


2.59 


2.31 


2.68 


1.11 





1.48 



CIDER FROM APPLES AND PEARS. 331 

Of these samples the first four had undergone a good fermen- 
tation. They furnish the following average composition for the 
principal constituents : 

Alcohol, per cent, by volume ..... 5.2 

Extract, per liter, at 212 F 41.18 

Sugar 8.90 

Asli 2.87 

The other four samples were partially unferrnented, or sweet, 
ciders. Their average composition was as follows : 

Alcohol, per cent, by volume ..... 1.70 

Extract, per liter, at 212 F 66.98 

Ash 2.56 

From these means the municipal laboratory deduces the fol- 
lowing as a type of composition for pure ciders : 



Alcohol, per cent, by volume 
Extract, per liter, at 212 F. 

A ~1. 



. 5.66 
. 30.00 
Ash . 2.80 



Recent analyses of pure ciders, from different parts of France, 
published by M. G. Lechtartier, have shown great variations 
from this type, and show the necessity for the examination of 
large numbers of samples from various parts of the country for 
the establishment of a proper standard of analysis. 

Analyses of ciders by the United States Agricultural Department. 
The samples for the investigation were purchased in the city in 
the same manner as samples of wine and beer : 



332 



VINEGAR, CIDER, AND FRUIT-WINES. 



1 


"7. 


'> 








9J 


$ 




OD 


2 


gS 






















eg 




Designation. j ^ 


a 

A 


g 


31 


if = 


a 


-3 
&- 


8* . 




fl 


'a 


te -r. . 


I 5* 





'3 








y> oj 


si O 


. 


3 





S2 g 


i 


O 


a, 


^ 






f 5 






^ 


g 


"Q CO 




85 


co 


< 


*" 


H 


ta 


03 


* 


< 


u 





Well fermented ciders. 
Draft cider ("extra dry") 4S30 


1 


1.0132 


p.ct. 
4. IS 


p.ct. 
5.23 


p.ct. 
3.31 


p.ct. 

.602 


p ,ct 


p.ct. 
.396 


p.ct. 
.038 


p.ct. 


O 

195 


Bottled cider, known to 4852 


2 


1.0003 


8 09 10 05 


1.88 


.456 





.279 


.063 trace 


7 


be pure 
Bottled cider . . . 4S33 


3 


1.0007 


6.28 7. S3 


1.80 


.376 





.340 


.044J _ 


6.1 


Bottled "extra dry rus- 4S34 


4 


1.0264 


4.48 5.61 


5 52 


.339 





.393 


.031 





35.2 


set" cider 






















"Champagne cider," bot- 48 >5 


5 


1.0223 


4.08 5.10 


502 


.567 





.310 


.050 


.161 


23.4 


tied 
' Champagne cider," bot- 4836 | 6 


1.0143 


545 6.79 


3.69 


.361 





.415 


.038 


.120 


20.4 


tl'>d 




















"Sparkling cider," bot- 4927 


7 


1.0306 


3.63 454 


5.92 


.113 





.506 





(2) 


33.8 


tied 






















Average ... 


- 


1.0154 


5.17 


6.45 


3.88 


.402 


- 


.377 


.Oi4 


- 


- 


"Sweet" or incompletely 
























fermented ciders. 
























Draft cider . . . 4829 1 


1.0537 


! 0.65 O.S1 


9.34 


.565 


- 


.315 


.069 





41.6 


"Sweet" cider . . 4S31 2 


1.0516 


0.61 77 


9.59 


.302 





.270 


.063 


3i.2 


















I 




"Sweet" cider (draft) .4837 3 


1.0567 


0.20' 25 


9.53J .375 


.283 


.075 





18.4 


Do 4838 4 
Do 4839| 5 


1.0203 
1.0552 


343 4.33 3.84 
0.55! 0.67 9.75 


.302 
.409 





.374 
.336 


014 
.031 





24.2 
4S.5 


Do i 4841 


6 1.0355 


! 2.96 | 3.71 

1 


6.98 


.478 


-' 


.348 


.069 


39.1 


Average ... 


- 


1.0455 


1.40 1.76 8.17 


.405 


- 


.321 


.059 

1 


- 



1 A circumstance arising after the samples had been thrown away seemed to throw con- 
siderable doubt upon the determinations of sugar, which were made by an assistant, and 
the entire set had to be thrown out. 

2 Determinations of the carbonic acid in three different bottles gave the following 
results: .728, .634, .482. 



The choice of the varieties of apples is of great importance in 
the manufacture of cider. All apple juice will not make equally 
good cider, even if it is equally well handled. It is not always 
the best flavored apple or the best tasting juice that will make 
the best cider. Indeed, as a rule, the best cider is made from 
apples which are inferior for table use, such as the crab-apple 
and the russet. But it is a pretty general rule that the most as- 
tringent apple will make the best cider. This astringeucy is due 
to an excess of tannin. While a portion of this tannin is changed 



CIDER FROM APPLES AND PEARS. 333 

to sweetness a considerable portion remains, which serves to render 
the cider more easily and thoroughly clarified and to make it keep 
better. The tongue alone being, however, not sufficient to detect 
the tannin in apples, the following will serve as a reliable test : 
Express the juice of a few apples and add a few drops of isinglass, 
which combines with the tannin and forms a precipitate. From 
the greater or smaller quantity of this precipitate a conclusion 
can be drawn as to the quantity of tannin present. The specific 
gravity of the juice, which may vary between 1.05 and 1.08, 
should be determined. The greater the specific gravity of the 
juice the better the respective variety of apple is for the fabri- 
cation of cider. According to these directions, the raw material 
should be selected, though in most cases it will be necessary to 
use a mixture of different varieties. In France, for a quality of 
cider w r hich will keep well, the apples are mixed in the following 
proportions : f bitter-sweet and J sweet apples. If a sweet cider 
is wanted not intended to be kept for a long while, J bitter-sweet 
and f sweet apples are used. 

The most noted varieties of apples said to possess peculiar and 
natural properties for the manufacture of refined cider or apple- 
wine are the " Harrison" and " Canfield" of New Jersey, from 
which the celebrated New Jersey cider is almost exclusively 
manufactured. Of the Harrison 600 Ibs. suffice for the manu- 
facture of 30 gallons of cider. Another variety is the " Hagloe 
crab,' 7 which is also excellent for cooking. Other varieties re- 
commended by P. Barry* are the Dartmouth, Hyslop, and 
Hewe's Virginia crab. The Siberian crab (Pyrus baccate.) is 
also highly recommended for the fabrication of cider as well as 
for jelly. 

The following is a select list of apples recommended by P. 
Barry for cultivation in the Eastern and Middle States.f 

Summer. Early Harvest, Early Strawberry, Golden Sweet, 
Large yellow Bough, Primate, Red Astrachan, Williams's Favo- 
rite. 

* Barry's Fruit Garden, New York, 1883. 

t The name given to each fruit is the recognized name of the American 
Pomological Society as far as recorded in their catalogue. 



334 VINEGAR, CIDER, AND FRUIT-WINES. 

Autumn. Chenango Strawberry, Duchess of Oldenburgh, Fall 
Pippin, Gravenstein, Hawthoruden, Jefferis, Jersey Sweet, Kes- 
wick Cadlin, Lowell, Lyman's Pumpkin Sweet, Porter, St. Law- 
rence, Stump. 

Winter. Baldwin, Esopus, Spitzenburgh, Fameuse, Golden 
Russet of Western New York, Hubbardston, Nonsuch, Jonathan, 
King of Tompkins County, Lady Apple, Monmouth Pippin, 
Mother, Northern Spy, Peck's Pleasant, Pomme Grise, Red 
Canada, Rhode Island Greening, Roxbury Russet, Sutton Beauty, 
Talman's Sweet, Twenty-ounce, Wagener, Yellow Bellflower. 

For the West and South. Nearly all the summer and fall 
varieties succeed well at the West and South. In California and 
Oregon our best northern sorts generally succeed, but the winter 
varieties of the South will be better adapted to the warmer dis- 
tricts of California than our Northern winter sorts. 

The apples intended for the preparation of cider should be 
allowed to attain complete maturity, which is recognized by their 
color, the dark hue of the pips, little specks covering the skin, 
and by the sharp and agreeable ethereal odor emanating from 
them. In fact they should be allowed to remain on the trees as 
long as vegetation is active or until frosts are apprehended, for 
thus the conversion of the starch into sugar is best effected and 
their keeping better secured than by storing. They should be 
gathered by the hand to prevent bruising and coming in contact 
with dirt. They are then placed in piles and allowed to sweat. 
This sweating process has a tendency to ripen the fruit and make 
it uniform, thereby improving the flavor as well as the quality 
and strength of the cider in consequence of the apples having 
parted with six or eight per cent, of w r ater. The strongest cider 
is made from apples containing the smallest percentage of juice, 
and, in its aqueous solution, the largest proportion of saccharine 
matter. If the weather be fine, the piles may be exposed in the 
open air upon clean sod or where this is wanting upon boards or 
linen cloths, but under no circumstances should the apples be 
placed upon the bare ground or upon straw, as they contract an 
earthy or musty taste which is afterwards found in the cider. 

After sweating and before being ground the apples should be 
wiped with a cloth to free them from exudations and adhering 



CIDER FROM APPLES AND PEARS. 335 

particles of dirt, and if any are found bruised or rotten they 
should be thrown out. Ripe, sound fruit is the only basis for a 
good article of cider, and the practice of mixing rotten apples 
with the sound, as is frequently done and even advocated by 
some, cannot be too strongly condemned. Mellow or decaying 
apples have lost almost all their perfume, a certain quantity of 
water by evaporation, and a large portion of their sugar. Rotten 
apples yield a watery liquid of an abominable taste, which pre- 
vents the cider from clarifying and accelerates its acetification. 

The apples being wiped, sorted, and, if necessary, mixed in the 
desired proportions, are now brought into the grinder and reduced 
to an impalpable pulp. By this operation the numerous infini- 
tesimal cells of the apple should be thoroughly broken up so as 
to permit the free escape of the juice when under pressure, and 
the machine which accomplishes this most effectually is the best 
for the purpose. If the cells are not thoroughly torn asunder, 
their tendency is to restrain and hold, as it were, in a sack much 
that otherwise would escape. As regards the crushing of the 
seeds there is a diversity of opinion, some holding that they 
communicate to the cider a disagreeable bitterness and acidity, 
while others consider them as rendering the cider more alcoholic 
and making it keep better. 

According to M. Bergot, for cider of superior quality it is pre- 
ferable not to crush the seeds, because the diffused odor of the 
essential oil would undoubtedly injure the fine taste of certain 
notable products. For ordinary cider the crushing of the seeds 
will, on the other hand, be of advantage, because their essential 
oil helps to give to the cider the bouquet which it otherwise 
lacks. For cider intended to be converted into brandy the seeds 
must, however, be crushed. The grinder should be cleansed with 
hot water every evening or at least every third day. 

The treatment to which the pulp obtained by grinding is sub- 
jected varies according to the color the cider is to have. Where 
the consumer prefers a pale-yellow color the pulp must at once 
be pressed, while for a darker color it is allowed to stand 1 2 to 
18 hours. 

The next step in the operation is pressing. The various kinds 
of presses, racks, and manner of laying up the cheese have 



336 VINEGAR, CIDER, AND FRUIT-WINES. 

already been described. The primitive custom of laying the 
cheese was to lay upon the platform of the press a quantity of 
straw, upon which a quantity of pomace was placed, and the 
edges secured by laps of straw, thus alternating straw and 
pomace until the pile was complete. The object of using the 
straw was to hold the mass together while it was being submitted 
to pressure, and also to serve as a means of exit for the cider. 
An improvement was in the substitution of hair-cloths, and 
within the past few years the adoption of the cotton press-cloth 
and racks to hold the pomace in laying up the cheese for the 
press. The racks have already been described ; the press-cloth is 
woven from yarn made expressly for the purpose and is of equal 
strength in warp and filling. The G. H. Bushnell Company, of 
Thompson ville, Connecticut, furnishes several grades of cotton 
press-cloth, medium, heavy, and extra heavy. The use of straw 
in laying up the cheese should be entirely discarded, as the 
slightest mustiness imparts an unpleasant odor to the cider. 

The pressure applied to the cheese should be slow at starting 
and then gradually increased until finally the full force is applied. 
The juice as it comes from the press runs through a fine hair-sieve 
into a receiver. With a good press about 65 to 75 per cent, of 
the juice will be obtained. 

After the cider has been extracted and the cheese removed from 
the press the pomace may be utilized for the manufacture of vine- 
gar, as described on p. 168. In France it is, however, used for 
the manufacture of the small cider. The method is as follows : 
After the extraction of the pure cider by the first pressing, the 
pomace is taken from the press, and after adding 15 liters of 
water for every hectoliter of apples used, the mass is allowed to 
macerate 15 to 20 hours, care being had to stir every two or 
three hours. Then this pulp is put a second time under pressure 
and a quantity of juice extracted equivalent to the amount of 
water added. 

Extraction of the juice by diffusion. Diffusion, which gives such 
excellent results in the extraction of sugar-beets, has also been 
applied to extract the soluble constituents of the apple, but in 
Huch a primitive manner that the juice thus obtained produces 



CIDER FROM APPLES AND PEARS. 



337 



after fermentation a beverage very deficient in alcohol and diffi- 
cult to keep. 

M. Jules Nanot, of Paris, France, proposes the following im- 
proved method : 

Suppose we take 150 kilogrammes of apples reduced to pulp, 
divide them in 3 lots of 50 kilogrammes each and put each lot 
in a vat or tub. These tubs are then placed on steps one above 
the other as shown in Fig. 74. They communicate with each 
other by means of spigots provided in the interior with small 
convex screens. Care must be had to keep the tubs covered not 



Fig. 74. 



Nol 




only to prevent the pulp from floating but also to prevent oxida- 
tion, as otherwise, on account of the mass remaining exposed to 
the air for a long time (3 times 24 hours), would yield cider 
which afterwards would turn black. 

First manipulation. Pour 50 liters of water into tub No. 1, 
and macerate 24 hours. 

Second manipulation. Draw off the liquid in No. 1, by opening 
the spigot into No. 2, and pour again 50 liters of water into 
No. 1, and macerate for 24 hours. 

Third manipulation. Draw off the liquid from No. 2 into No. 
3 and the liquid from No. 1 into No. 2. Pour 50 liters of water 
into No. 1 and macerate for 24 hours. 

Fourth manipulation. Draw off the liquid from No. 3. Then 
draw off the liquid from No. 2 into No. 3, and from No. 1 into 
No. 2. Now remove No. 1 and replace its exhausted pulp with 
22 



338 VINEGAR, CIDER, AND FRUIT-WINES. 

freshly ground apples ; then instead of putting it in the highest 
place, place it at the bottom and shift Xos. 2 and 3 one step 
higher up, so that No. 2 becomes 1, Xo. 3, 2, and Xo. 1, 3. Then 
draw off the liquid in Xo. 2 into Xo. 3 and that of Xo. 1 into 
Xo. 2. 

Xow pour 50 liters of water into the upper tub X"o. 1 and repeat 
this every 24 hours. The liquid which is drawn off every 24 
hours from the lowest tub is poured into the barrel in which it is 
to ferment. 

At first this fourth manipulation seems complicated, but after 
having done it once there will be found no difficulty in its 
execution. What seems to complicate it somewhat is the indis- 
pensable placing of the tub with the freshly crushed apples on 
the base of the steps in order to have the richest juice discharged 
into it. To briefly recapitulate : the most exhausted apples are 
always placed at the top of the steps and the less dense liquid 
added to them and the freshest apples on the bottom to receive 
the richest juices. 

By this disposition the apples are thoroughly exhausted, and 
after having passed through the operation the liquid obtained 
will show an alcoholic strength equal to f of the alcohol contained 
in the pure juice, and is at all events greatly superior to the juice 
obtained by the old methods of diffusion. 

The use of this method Avould be suitable for persons having 
no cider press and only a small quantity of apples to manipulate- 

The quantity of cider is nearly equal to that obtained by three 
pressures and the juice obtained by diffusion is almost as rich as 
jthe juice yielded by the press. 

After one or two manipulations it is quite easy to operate sue- 
eessfnlly without weighing the apples and also the water to be 
used. It is sufficient for that purpose to mark on the inner side 
of the tub the height to which a certain quantity of crushed 
apples come, and measure the water in the same manner. In 
order to pass the liquid into the next lower tub and draw it off 
finally from the last tub, it is sufficient to open the spigots and 
allow the liquid to run off naturally. The quantity of liquid 
thus drawn off is less by about T \ the amount poured in at the 



CIDER FROM APPLES AXD PEARS. 339 

commencement of the operation. It is impossible to extract all as 
that would require the use of a press. 

Unfortunately this process of diffusion is very slow on account 
of the necessarily small size of the tubs, and their capacity can 
scarcely be increased as in that case two men would have consid- 
erable difficulty in raising them from one step to the other. 

In order to accelerate this method and apply it to the produc- 
tion of large quantities of cider large tubs would be required, and 
instead of disposing them on steps they would have to be placed 
on the floor of the room and the passage of the liquids from one 
tub to the other be effected by a system of pumps. The number 
of tubs might then be increased to five or six ; and by the appli- 
cation of heat a more complete exhaustion of the apples could be 
reached. 

Recent successful experiments in expressing the juice of the 
grape by means of the centrifugal would indicate that the same 
method might also be applied to apples. 

The juice of the apples obtained by either of the preceding 
methods is now tested with the must areometer as to its saccharine 
content. If it is too low it will be useless to try to make cider 
of it unless that quality is strengthened. Generally good juice 
will range from 10 to 14 per cent. If it is any less than 10 per 
cent, it will not make a cider which will keep, though, if the 
flavor in other respects is all right, a very light cider for immedi- 
ate use may be produced from it. 

The juice having been tested and, if found wanting in saccharine 
strength, corrected by the method given on p. 326, the next step in 
the operation is fermentation. For this purpose the juice is brought 
into clean, sound barrels or into large vats. After a few hours 
an active fermentation will commence, which is usually permitted 
to continue, with the bung loose, until the hissing sound, so readily 
discernible when carbonic acid gas is escaping, shall cease. The 
cider is then drawn off into clean barrels, separating it from the 
sediment. The barrels are placed in a cellar or a cool room 
having a uniform temperature, one of 57 to 64 F. being most 
suitable. Abrupt variations in temperature should be carefully 
avoided and provided against. The barrels must be carefully 
watched, and as soon as white bubbles are perceived rising at the 



340 VINEGAR, CIDER, AND FRUIT-WINES. 

bung-hole, the cider is again racked off into other barrels whereby 
fermentation is, of coarse, interrupted. The distinguishing char- 
acteristic between the fermentation of wine and cider may here be 
referred to. Wine is allowed to completely ferment without 
interruption, but the fermentation of cider must be checked at a 
certain time as otherwise acetic acid commences to form, the pro- 
gressive development of which would in a year render the cider 
unfit to drink. For the preparation of cider on a large scale 
skill in handling the must areometer is absolutely necessary, and 
care should be had not to allow the entire content of sugar to be 
converted into alcohol. Generally speaking cider must be racked 
three times, but each time only when the previously mentioned 
white bubbles appear at the bung-hole. Where the barrels can 
be placed in a cellar having a temperature of 32 F., or not much 
above it, fermentation can be readily checked. Such cellars 
being, however, rare, recourse must be had to artificial means to 
effectually prevent any further fermentation. Various methods 
have been practised with a view to accomplish that object, one of 
which was to thrust a lighted sulphur match into the bung-hole 
of the barrel. This method is, however, but little used at the 
present time. Another plan which can be recommended is to 
submerge in the barrel ground brown mustard-seed tied in a bag. 
But the most effectual method, and which is generally used by 
professional cider makers, is to add from J to J oz. of sulphite of 
lime to each gallon of cider in the barrel, first mixing the powder 
in about a quart of the cider, then pouring it back into the barrel 
and giving it a thorough shaking or rolling. The sulphite of 
lime must be used, and not the sulphate. It will preserve the 
sweetness of cider for many years, but care must be had not to 
use too much, as otherwise it will impart a taste of sulphur to the 
cider. 

For the preparation of very fine cider throw J Ib. of white 
sugar into the barrel and suspend a bag of raisins in it by 
squeezing one corner between the bung and bung-hole. 

The oiling process is another method of checking fermenta- 
tion. It consists in pouring into the bung-hole of a barrel about 
half a pint of sweet oil. The oil should be warm when poured 
in to enable it to spread in a thin coat over the surface and keep 



CIDER FROM APPLES AND PEARS. 341 

spreading as the cider is drawn down, thereby preventing the air 
from coming in contact with the surface of the cider and con- 
verting it into acetic acid. 

We will here call attention to salicylic acid, which as an agent 
for checking fermentation might be even more effective than sul- 
phite of lime or powdered mustard-seed. The " salicylic acid 
question," as it is called, has received a great deal of attention 
for several years in Europe, and much has been written pro and 
con on the question of the propriety of its use as a preserving 
agent in articles of food and drink. In France its use as a pre- 
servative in any form of food or drink was forbidden by minis- 
terial decree on the 7th of February, 1881. This decree was 
based upon the decision of the consulting committee of hygiene 
that its constant use was dangerous to health. 

In Germany its use is prohibited except in beers intended for 
export to other countries where its use is allowed. 

Its prohibition in France called forth a great deal of opposition, 
and experiments were made and published indicating that its con- 
stant use in small doses exerted no injurious influence upon the sys- 
tem. In this country but little attention seems to have been given 
to the use of salicylic acid as a preservative, and, as far as we know, 
no experiments have been made with it in checking fermentation 
in cider. Whether its use for many years and without regard to 
age, sex, or personal idiosyncrasy is harmless or not, is at least 
still an open question. Moreover, the quantity used is so ex- 
ceedingly small that its injurious effect upon the health of 
moderate drinkers of beer, wine or cider would seem rather 
doubtful. For wine the limits of its addition lie between 0.02 
and 0.1 gramme per liter. For use dissolve the salicylic acid to 
a concentrated solution best in pure spirits of wine free from fusel 
oil or in the wine itself and add the determined quantity. To 
find the latter dissolve 5 grammes of crystallized salicylic acid in 
100 cubic centimetres of spirits of wine or of wine and add a 
series of quantities of this solution, commencing with 1 cubic 
centimetre and gradually increasing to 2 cubic centimetres, to the 
wine. These quantities represent 0.5 to 0.1 gramme of salicylic 
acid per liter. A larger content of sugar in proportion to the 
content of alcohol requires somewhat more salicylic acid. 



342 VINEGAR, CIDER, AND FRUIT-WINES. 

The cider being protected from further fermentation by either 
one of the above-mentioned methods is allowed to lay undisturbed 
until April, when it can be bottled or for quick consumption 
tapped from the barrel. But before being offered for sale it has 
to be clarified like other wine. According to the old method 
this was done with isinglass, 30 grammes of which were allowed 
for each barrel. This quantity was dissolved in J liter of cider 
over a moderate fire and the solution when cold poured with con- 
stant agitation into the barrel. Drawing off can be commenced 
after eight days. 

A better mode of clarification, Avhich at the same time increases 
the purity of the taste of the cider, is as follows : For each barrel 
of 30 gallons take 4 Ibs. of fresh wheat bran, and after washing 
it twice in hot water to remove all soluble substances, press out 
thoroughly. Now dissolve about 2 drachms of alum in a bucket- 
ful of hot water and pour the solution upon the bran. After 6 
to 8 hours take the latter from the alum water and press as be- 
fore. The bran is best used before the cider is racked off for the 
third and last time. Stir it into the cider and then draw off the 
latter through a fine strainer into the actual storage barrel. The 
cider first passing through the strainer is generally somewhat 
turbid, and must be poured back until it runs off clear. 

In France the cider is generally clarified by dissolving 60 
grammes of catechu in 1 liter of cider and adding the solution to 
1 hectoliter of cider, with constant stirring. The tannin thus 
added precipitates the albuminous matters, the result being a 
clear cider which will not blacken in the air. 

Cider intended for export must be made somewhat richer in 
alcohol, which is generally done by adding sufficient French 
brandy to increase its content of alcohol 2 per cent. Sometimes, 
also, i Ib. of sugar for every 2 quarts of juice is added during 
fermentation. For shipping to tropical countries experiments 
might be made with salicylic acid, adding it in the same propor- 
tion as to beer, which is for beer sent in barrels 20 grammes per 
hectoliter, and for bottled beer 15 grammes. 

There are several methods of improving the taste of cider, but 
they are rather questionable, because tastes differ, and what 
might be considered an improvement by one would be declared 



CIDER FROM APPLES AND PEARS. 343 

a defect by another. , A favorite means of improvement is as' 
follows : For 45 gallons of cider measure oif 3 quarts of French 
brandy and mix it with the following substances, all finely pow- 
dered : 0.7 drachm of bitter almonds, 0.7 drachm of mace, and 
7J drachms of mustard-seed, and finally 3J drachms of catechu, 
previously dissolved in water. Pour this mixture into the cider 
and shake the barrel frequently during the next 14 days. Then 
allow it to rest three or four months, and should it then not run 
oif clear, when tapped, clarify it with 1J oz. of isinglass or the 
whites of a dozen eggs. If the color of the cider is to remain 
pale yellow, catechu cannot be used, and instead of isinglass or 
white of egg, skimmed milk is to be used for clarification. For 
a reddish color which is sometimes desired use If drachms of 
powdered cochineal in place of the catechu. 

Sometimes cider is prepared in the same manner as other -fruit- 
wines. In this case J Ib. of sugar is added to every liter of juice, 
and the latter is allowed to completely ferment in the same man- 
ner as grape-wine. According to another direction, add to every 
2 quarts of juice 2 Ibs. of white sugar and boil as long as scum 
is formed; then strain through a fine hair-sieve and allow to cool. 
Now add a small quantity of yeast, stir thoroughly, let the whole 
ferment three weeks, and after clarifying rack oif into bottles. 

Red apple-wine, or, as it is frequently called, red wine from 
cider, is prepared as follows : Boil for 2 hours 50 quarts of apple 
juice, 27 Ibs. of honey, 1 oz. of tartar, 6 Ibs. of comminuted red 
beets, and 3 Ibs. of brown sugar. Let the fluid completely fer- 
ment, and if no apple juice is on hand to fill up the barrel during 
this process use solution of sugar. When fermentation is fin- 
ished pour a mixture of 1 quart of French brandy and about 1 
drachm each of pulverized cinnamon and ginger into the barrel. 
After three months clarify the wine and rack oif. 

Sweet dder can be prepared in the following simple manner : 
Boil the juice as soon as it comes from the press for two hours, 
removing the scum which arises. Then pour the hot fluid into 
bottles previously placed in warm water, cork and seal with a 
mixture of resin and tallow, in the proportion of 1 Ib. to 4 
drachms, kept in a fluid state. After sealing hold the neck of 



344 VINEGAR, CIDER, AND FRUIT-WINES. 

the bottle in cold water for one minute. Thus treated the sweet 
cider will keep seven or eight months. 

In his treatise on Cider, Dr. Denis-Dumont gives the following 
directions for bottling cider. The cider is to be bottled at three 
distinct periods. It should never be bottled before the tumul- 
tuous stage of fermentation is entirely completed and the liquid 
clarified. 

First period. At the termination of the tumultuous fermenta- 
tion the cider still contains considerable sugar; fermentation con- 
tinues in the bottle and produces in a few weeks a large quantity 
of carbonic acid. In order to prevent the bottles from being 
broken by the pressure, champagne bottles should be selected 
and care taken to have them stand upright until about the 
month of July, i. <?., until the development is considerably re- 
duced. The bottles are then laid on their side, as otherwise the 
cider would cease to be sparkling. This cider has to be kept for 
a number of years, it being good to drink only when old. 

Second period, when fermentation is more advanced, about six 
weeks or two months after the first period. Mineral water 
bottles are strong enough to hold this cider, it liberating less car- 
bonic acid than the preceding. The bottles are left in an upright 
position for a few weeks only. 

This cider has a good flavor and is fit to drink much sooner 
than the preceding. It keeps for a long time. 

Third period, when fermentation is complete or almost so, any 
quality of bottles may be used, a great deal less of carbonic acid 
being developed than in the preceding cases. The bottles should 
be laid down immediately after filling, in order to retain the car- 
bonic acid which will still be developed. 

This cider is not sparkling ; it is, however, lively, strong, and 
lias a fine flavor. 

The bottles should in every instance be well corked and the 
corks,^for the sake of safety, tied. The cider is very good when 
kept in small bottles, better in quart bottles, and best in jars 
holding two quarts. A few moments before opening a bottle of 
sparkling cider it is advisable to provide a minute opening for 
the escape of the gas by piercing the cork with a fine punch. As 
soon as the tension of the gas has become sufficiently weak the 



CIDER FROM APPLES AND PEARS. 345 

cork is allowed to blow out in the same manner as with cham- 
pagne. Without this precaution most of the cider might be 
thrown up to the ceiling. 

In the Island of Jersey, where the manufacture of cider is car- 
ried on in a very rational manner, the juice as it comes from the 
press is allowed to ferment in large open vats placed in a cellar 
having a uniform temperature of from 53 to 59 F. On ac- 
count of the large surface presented to the air tumultuous fer- 
mentation soon sets in and in about four or five days, or at the 
utmost a week, fermentation is over. The liquid is then drawn 
off in barrels, thoroughly cleansed and sulphured, in which fer- 
mentation continues slowly. These barrels are not entirely 
filled, and when the development of carbonic gas has proceeded 
so far that the flame of a lighted candle introduced by the bung- 
hole is extinguished, the liquid is drawn off into other barrels 
sulphured like the first. This transfer from one set of barrels to 
another is continued until no escape of gas is perceptible, i. e., 
until fermentation is quite complete. 

Prepared in this manner the cider will keep perfectly good for 
several years, and stand transportation by sea without any diffi- 
culty. 

Devonshire-cider is made from a mixture of one-third of bitter- 
sweet apples with a mild sour. These being gathered when thor- 
oughly ripe are allowed to undergo the sweating process before 
grinding ; the cider is then pressed in the usual manner and strained 
through a hair-sieve into hogsheads, where it remains for two or 
three days previous to fermenting. It is then drawn off into clean 
casks to stop the fermentation, but if this is very strong only two or 
three gallons are first put in, and, after burning cotton or linen rags 
saturated with sulphur in the cask, thoroughly agitated. This com- 
pletely stops fermentation in that quantity and usually checks it in 
the other portion with which the cask is then filled up. In a few 
weeks the cider becomes very fine. If this be not satisfactorily 
accomplished by the first operation it is repeated until fermenta- 
tion is completely checked and the cider is in a quiet state and in 
a proper condition for drinking and bottling. 

Heating of cider. G. Lechartier has made numerous experi- 
ments to preserve cider by heating in bottles or in barrels holding 
from 25 to 230 quarts. The experiments showed that a tempera- 



346 VINEGAR, CIDER, AND FRUIT-WINES. 

ttire of 140 F. suffices to suppress every kind of fermentation in 
cider which contained only 3 to 6 per cent, of alcohol. But in all 
cases the cider thus treated acquired a peculiar taste calling to mind 
that of dried fruit. The following experiments show how this evil 
can be removed : On April 16, 1888, barrels holding from 25 to 50 
quarts were filled with cider previously heated to from 140 to 
149 F. ; on June 14, of the same year, the peculiar taste, re- 
ferred to above, was noticed, though no change in the composi- 
tion by alcoholic or acetous fermentation had taken place. To 
the content of every barrel was now added a bottle of the same 
cider not previously heated, whereupon regular alcoholic fermen- 
tation set in anew. On July 9, of the same year, the cider had 
lost the taste of dried fruit and re-acquired its original taste. On 
July 11, of the same year, it was drawn off into bottles, was spark- 
ling in September, and retained its normal taste. The process hav- 
ing been tested by experts, the Congress of the "Association pomolo- 
gique de 1'Ouest," held at Havre, expressed a favorable opinion of 
it and declared the problem of keeping cider sweet as solved. 

Freezing of cider. G. Lech artier also made experiments in 
this direction, his object being to answer the following questions: 

1. Are the aroma, taste, and clearness of cider changed by cold? 

2. Of what nature are the products obtained by freezing, and 
does the latter take place without sensible loss of substance? 3. 
Are the ferments killed by sufficiently long cooling, and is cider 
thus treated protected from external influences? 

For all the experiments the cider was subjected to a tempera- 
ture of from 0.4 to 4 F. A portion of the fluid congeals, 
and the temperature rises to from 26.6 to 24.8 F. As soon as 
a sufficient quantity has become solid the fluid portion is poured 
off, which has a higher specific gravity than the original cider. 
The ice crystals melt to a nearly colorless fluid, which has a 
specific gravity of 1 and contains only 0.3 per cent, of alcohol. 
From ciders with 4 to 5 per cent, of alcohol were obtained by 
freezing concentrated ciders with 7 to 8 per cent, of alcohol, and 
60 to 80 grammes of dry extract per liter, which corresponds 
with the composition of the richest Normandy cider. These 
ciders, after remaining for several months in bottles, differed but 
little as regards color, content, and taste from the best products 



CIDER FROM APPLES AND PEARS. 347 

of Normandy as certified to by the Congresses of the "Associa- 
tion pomologique de 1'Ouest," held in Versailles and Havre. 
The results thus obtained are entirely different from those by an 
addition of sugar to the must. While the addition of sugar only 
increases the content of alcohol, by freezing all the constituents 
derived from the apple are concentrated, and the same time also 
the taste and aroma. For this reason, ciders having a slight 
by-taste cannot be improved by freezing. The value of light 
ciders of a pure and agreeable taste is, however, greatly enhanced 
by the treatment. As regards the third question, G. Lechartier 
arrives at the conclusion that must and cider in various stages of 
fermentation are not sterilized even by cooling for 212 hours, 
the process of fermentation only being retarded during the time of 
cooling. 

Champagne-cider. The manufacture of this beverage has 
recently become quite important it resembling the ordinary but 
more expensive champagne-wine, and being frequently sold as 
such. Since the devastation of the vineyards by the phylloxera, 
a large trade in this spurious champagne-wine is carried on in 
France. Champagne-cider, manufactured in New Jersey, is 
exported to France, where it is repacked and provided with 
genuine champagne labels. It is then re-shipped to New York 
as genuine champagne. This champagne-cider if sold under its 
right name is an excellent beverage. It is prepared as follows: 
To 50 gallons of apple-juice add 12 quarts of brandy and 14 
Ibs. of sugar or honey. Mix the whole thoroughly, and allow 
it to ferment for one month in a cool place. Then add about 4 
drachms of orange-blossom water, and clarify with 2 quarts of 
skimmed milk. The champagne is now ready and is racked off 
into bottles, into which a small piece of white sugar is thrown, 
and the corks of which are wired. The duration of fermentation 
has been stated as one month ; it may, however, last a few days 
more or less, it being entirely a matter of observation when the 
most suitable time for racking off has arrived. No more rising 
of bubbles of gas should be observed, but fermentation must not 
be completely finished. 

According to another direction, 40 quarts of fermented apple- 
juice are mixed with 2 quarts of solution of sugar, J quart of 



348 VINEGAR, CIDER, AND FRUIT-WINES. 

rectified alcohol, and 2 ounces and 4 drachms of pulverized 
tartar. The mixture is allowed to stand 24 hours and then 
racked off into bottles, each bottle receiving a drachm of bicar- 
bonate of soda. Cork and wire. 

Another process consists in bringing into a vat of 40 quarts 
of apple-juice, 5 pounds of white sugar, J pound of tartar, 1 
pint of rectified alcohol, J pint of yeast, and 1 ounce, 2J drachms 
of 'acetic ether. The mixture shortly before fermentation is 
finished is drawn off into bottles, each of which has been pre- 
viously provided with a small piece of sugar. Clarification with 
isinglass, white of egg, or skimmed milk must, of course, precede 
the drawing off into bottles. The bottles must be thoroughly 
corked and wired in the same manner as genuine champagne, 
and laid in a cool cellar. 

Cider serves frequently as a basis for artificial wines, genuine 
Burgundy, sherry, or port- wine, prepared from cider mixed with 
suitable substances, being frequently served even in first-class 
hotels. Nothing could be said against these beverages if they 
were sold under their proper names, because they consist of harm- 
less substances, which cannot always be said of the genuine wines, 
they being only too frequently adulterated with substances injuri- 
ous to health. 

Burgundy. Bring into a barrel 40 quarts of apple-juice, 5 
pounds of bruised raisins, \ pound of tartar, 1 quart of bilberry 
juice, and 3 pounds of sugar. Allow the whole to ferment, fill- 
ing constantly up with cider. Then clarify with isinglass, add 
about 1 ounce of essence of bitter almonds, and after a few weeks 
draw off into bottles. 

Malaga-wine. Apple-juice, 40 quarts; crushed raisins, 10 
pounds; rectified alcohol, 2 quarts; sugar solution, 2 quarts; 
elderberry flowers, 1 quart; acetic ether, 1 ounce, 2 drachms. 
The desired coloration is effected by the addition of bilberry or 
elderberry -juice; otherwise, the process is the same as given for 
Burgundy. 

Sherry-mne. Apple-juice, 50 quarts; orange flower water, 
about 2 drachms; tartar, 2 ounces, 4 drachms; rectified alcohol, 
3 quarts; crushed raisins, 10 pounds; acetic ether, 1 ounce, 2 
drachms. The process is the same as for Burgundy. 



CIDER FROM APPLES AND PEARS. 349 

Claret-wine. Apple-juice, 50 quarts ; rectified alcohol, 4 quarts ; 
black currant-juice, 2 quarts ; tartar, 2 ounces, 4 drachms. Color 
with bilberry-juice. The further process is the same as for 
Burgundy. 

Diseases of cider. Ciders are subject to diseases which may be 
due to the bad quality of the apples used, a faulty method of 
fabrication, or bad management in the cellar. 

Badly fermented cider, especially such as has merely passed 
through the stage of tumultuous fermentation, or has been acidi- 
fied by contact with the air, is liable to produce serious disorders. 
The first, says Dr. E. Decaisne, being heavy and indigestible, 
inflates the intestines and produces diarrhoea ; the second, though 
of a sweet taste and a piquant and agreeable flavor, does not 
quench the thirst, but excites the nervous system and produces 
flatulency ; the third, which is really spoiled cider, causes inflam- 
mation of the intestines by the large amount of malic and acetic 
acids it contains. When in the fabrication of cider, water con- 
taining organic matter has been used, putrid fermentation is 
produced in the mass, the products of which impart some very 
deleterious properties to the cider. 

Acidity in cider may be due either to an excess of malic acid 
or of acetic acid. 

Some ciders contain too much malic acid when manufactured 
from apples not sufficiently ripe, or when, in mixing the apples, 
too large a proportion of sour apples has been taken. In both 
these cases the acidity may be neutralized by adding to the apple- 
juice 3 ounces, 8 drachms of potassium tartrate per 22 gallons. 
Sometimes there is an excess of acetic acid, due to the oxidation 
of the alcohol by long contact with the air. This defect is diffi- 
cult to remedy; it might have been prevented by means of a thin 
coat of olive oil, as previously mentioned, or by hermetically 
closing the bungs. The acidity will, however, disappear by 
putting in the bottles a pinch of bicarbonate of soda. It must, 
however, be done immediately on detecting the defect. 

Viscosity or greasy appearance of cider is recognized by the 
cider becoming stringy, viscous, and greasy, and is due to too 
great an abundance of gummy substances in the fruit, a lack of 
tannin, and, finally, to defective fermentation. In order to check 



350 VINEGAR, CIDER, AND FRUIT-WINES. 

this malady from its first appearance, add to every 228 quarts 1 
pint of alcohol or 2 grammes of catechu dissolved in 3 quarts 
of water. Cider may also be prevented from turning viscous by 
the addition of sugar to the juice when it comes from the press, 
which promotes fermentation. 

The cause of cider turning black is an excess of oxide of iron 
which, on coming in contact with air, becomes a peroxide and 
gives the beverage a brown color. The oxide of iron has been 
introduced into the cider either by the water used in its fabrica- 
tion, or by fruit grown on ferruginous soil. By mixing such 
cider with 12 drachms of powdered oak-bark per 22 gallons, a 
quantity of tannin is introduced which combines with the iron 
salt to an insoluble product that settles on the bottom of the 
barrel. Tartaric acid may also be used. 

Turbidity or lack of clarification of cider is caused by too small 
a quantity of sugar in the juice, or by imperfect fermentation. 

In rainy seasons the apples ripen imperfectly and contain but 
little sugar. Cider prepared from such fruit generally remains 
turbid. During seasons in which abrupt changes of temperature 
take place, and also when cold weather sets in very early, fer- 
mentation does not progress well, and clarification is imperfect. 
When the cider remains turbid after the first racking off, add a 
solution of 2 pounds of sugar in 1 gallon of water to every 132 
gallons of the liquid ; this sugar becomes converted into alcohol 
and renders the cider limpid. The use of lead salt, formerly much 
employed in Normandy, is very dangerous; persons drinking the 
cider thus adulterated feel sharp pains in the abdominal region, 
which present all the symptoms of lead colic, and may prove fatal. 

An admixture of lead salt is readily recognized. Add to the 
cider a solution of potassium iodide, if lead salt be present a yel- 
low precipitate of iodide of lead will be formed. 

Adulteration of cider. Cider is but little subject to adultera- 
tion according to most of the authorities on food. Even Hassall, 
who generally enumerates under each article of food a list of 
every conceivable adulteration that has ever been found or sup- 
posed to have been used in such food, only speaks of the addition 
of water, of burnt sugar as a coloring matter, and of the use of 
antacids for the correction of the acidity of spoiled cider. On the 



CIDER FROM APPLES AND PEARS. 351 

other hand, in France, where, as previously mentioned, the con- 
sumption of cider is very large, its adulteration is by no means 
uncommon. Dr. Bremont, in his address at the inauguration 
banquet of the cider exhibition, at Paris, in 1888 said : " People 
in Paris who have never travelled do not know what good cider 
is. The stuff sold as such at the bars and wine-shops here is 
simply abominable. A few years ago, it is true, it was possible 
to obtain good cider in Paris, because the demand for it was very 
small. Since, however, the wine sold became, in consequence of 
the phylloxera and the greed of the wine dealers, both very dear 
and very bad, the poorer classes took to drinking cider instead of 
wine, because it was much cheaper and, at that time, pure. The 
demand set the adulterators at work and increased the price of 
the drink. Cider now costs 12 cents a quart in every wine-shop, 
and in one case out of twenty it is pure and unadulterated. In 
most cases it is a filthy effusion of water poured on apples, sweet- 
ened with glucose and strengthened with vile alcohol." 

The above statement is fully confirmed by the report of the 
Paris municipal laboratory. Besides the washings of the dregs 
or residue, and watering, which is almost generally practised, some 
coloring matters are added ; salicylic acid and sulphites are also 
used to insure its keeping while in course of transportation, and 
an excess of acidity is covered by means of lime or of carbonate 
of soda. Brandies of inferior quality are added in order to cor- 
rect the flavor, and, as already stated, \vhite lead has been used 
to overcome an excess of acidity. Finally a frequent falsification 
is the fabrication of cider from apples crushed and dried by heat 
and starch-syrup. Of 63 samples examined in 1881, in the 
municipal laboratory, 39 were pronounced " bad," among which 
were 26 artificially colored; in 1882, 59 samples were examined 
of which 30 were declared "bad," of which 7 samples were arti- 
ficially colored ; 2 samples contained salicylic acid. The follow- 
ing is considered in the municipal laboratory as a minimum limit 
for the composition of a pure cider and any sample which falls 
below it in any constituent is considered as watered : 

Alcohol, per cent, by volume ..... 3.00 
Extracts, in grammes per liter .... 18.00 

Ash . .1.7 



352 VINEGAR, CIDER, AND FRUIT-WINES. 

This is for 11 completely fermented cider ; in sweet eiders the 
content of sugar should exceed the limit sufficiently to make up 
for the deficiency of alcohol, to which it should be calculated. 

Tn the samples of American ciders investigated by the United 
States Agricultural Department (sec p. W2) it was fully expected 
to find a considerable number preserved with antiseptics. This 
supposition failed to be confirmed, however, for no salicylic acid 
was found, and in but one case was any test obtained for sul- 
phites. None of the samples fell below the standard proposed 
by the French chemists, given above, and no metallic or other 
adulteration was discovered. 

There was, however, a single exception, No. 4927 in the table 
of analyses (p. :i>2), which was an embodiment in itself of nearly 
all the adulterations which have been enumerated as possible in 
cider. It was handsomely put up in neatly capped bottles, and 
was of a clear, bright color. Its tremendous "head" of gas when 
uncorked gave rise at once to the suspicion that it had received 
some addition to produce an artificial pressure of gas. The low 
content of free acid, together with the large amount of ash and a 
very variable content of carbonic acid in different bottles, estab- 
lished the fact that bicarbonate of soda had been added, probably 
a varying quantity to each bottle, while the dose of sulphites 
added was so large that a bottle has stood open in the laboratory 
all through the summer without souring. 

Manufacture of brandy from, elder. Brandy is a mixture of 
water and alcohol produced by the distillation of a fermented 
liquor ; it owes its aroma to the essential oil peculiar to the sub- 
stances subjected to distillation. 

In Normandy the heavy ciders only are distilled, ?'. <?., those 
containing the most alcohol. 

In years when there is an abundant crop of apples, it will gen- 
erally be found of advantage to distill the eider made from fallen 
fruit and also from early apples. The cider yielded by them does 
not keep well and brings a very low price, especially when there 
is a large product from late apples. 

Sour ciders should not be distilled, they being better utilized 
for the manufacture of vinegar. Spoiled cider, as a rule, makes 
bad brandy. 

Different qualities of cider should be distilled separately ; a 



CIDER FROM APPLES AND PEARS. 353 

skilful distiller can classify them by the taste and separates them 
in order to obtain brandy of first and second qualities. 

The cider is distilled when it is completely fermented, /. e., 
when the largest possible quantity of sugar has been converted 
into alcohol. Cider from early apples generally ferments faster 
than that from late apples and can be distilled towards the end of 
December, i. e., from six weeks to two months after its fabrication. 
Cider from late apples, made during December and January, is 
ready for distillation three or four months later, i. e. t in March or 
April. 

Preparation of the juice for distillation. When there is an 
abundant crop of apples and barrels are scarce, the juice as it 
comes from the press is brought into large open vats in which 
fermentation progresses rapidly, but in this case some beer yeast 
previously mixed with a small quantity of cider is added to each 
vat and the temperature must be maintained between 59 and 
68 F. Under these conditions the juice ferments very promptly 
and may be distilled eight or ten days later. 

Sometimes the whole of the pulpy mass obtained by grinding 
the apples is submitted to distillation. In order to accelerate 
fermentation a small quantity of hot water containing some sugar 
in solution is added to the mass, also one or two thousandths of 
sulphuric acid, the latter regulating the progress of fermentation. 

Fermentation being finished the mass is subjected to distillation. 
In order to prevent the mass from adhering to the still and 
burning, distillation must be conducted as slowly as possible and 
a small quantity of straw placed upon the bottom of the still, or, 
better, a piece of cloth to prevent direct contact of the mass with 
the heating surface. 

Plums, damsons, etc., are also subjected to distillation and pro- 
duce good brandy ; they ferment more slowly than wild cherries 
which produce the well-known cherry-bounce. Attention may 
here be called to the distillation of wild plums, which should be 
gathered in the fall when the leaves begin to drop. Some con- 
noisseurs consider brandy made from plums equal to that from 
cherries. On a farm no fruit containing sugar should go to waste 
as it can be converted either into brandy or vinegar. 

Distillation. For distilling cider on a small scale no expensive 




^ V , li 



354 VINEGAR, CIDER, AND FRUIT-WINES. 

apparatus is necessary, an ordinary still answering all require- 
ments. Cider is distilled like wine. The still is filled about j full 
and after placing the head in position the joints are carefully luted 
by pasting strips of cloth or even paper over them. The tub hold- 
ing the worm is filled with cold water and the fire started. The 
vapors escaping from the boiling liquid condense in the worm and 
run into the receiver. Heating should be done slowly in order to 
vaporize as little water as possible and especially to avoid sudden 
ebullition as the boiling liquid, getting into the head, would pass 
through the worm and become mixed with the liquor already 
distilled ; in such an event it would be necessary to begin distilla- 
tion anew. The operation is continued until the liquid produced 
contains hardly any alcohol which can be ascertained by the use 
of the alcoholometer or by the taste. It is unnecessary to say 
that care must be had to constantly renew and keep cold the 
water in the tub holding the worm. 

Distillation being finished the boiler is emptied and after 
thorough cleansing is refilled for a second operation. 

The liquid produced by successive distillations is mixed together 
and brought into the still a second time, whereby a liquor richer in 
alcohol and of a better taste is produced. It would be desirable 
if this second distillation or rectification could be effected by 
means of steam. This would prevent the empyreumatic taste 
which is often noticed in apple-brandy. The first and last runs 
of the still being of inferior quality are collected separately and 
poured back into the still when refilling for the next operation. 

Calculations have been made to establish by means of figures 
the immense advantage offered in a financial point of view by 
the distillation of cider. These theoretical calculations are, how- 
ever, frequently very deceptive. If, on the one hand, the producer 
knows the content of alcohol of his cider and, on the other, the 
market value of the alcohol and of the cider, it will be easy for 
him to decide which product will pay him best. 

Pear-cider. The manufacture of pear-cider is very limited 
and no great future can be promised for it, as even when most 
carefully prepared, it is far inferior to cider and other fruit-wines. 
Its fabrication is best understood in England, and how 7 little it is 
appreciated there is shown by the fact that three-fourths of the 



CIDER FROM APPLES AND PEARS. 355 

quantity manufactured is consumed by the farm-laborers. But 
any one who has large pear crops at his disposal and wishes to 
use a portion of them for the manufacture of a beverage should 
add to the pear-must one-quarter its quantity of must of bitter- 
sweet apples or a few quarts of black currant juice, which will 
improve the taste of the cider and its keeping qualities. The 
mode of preparation is the same as for apple-cider, though still 
greater care must be exercised in the choice of the raw material. 
The pears must have a sufficient content of sugar as otherwise 
the cider would not be sufficiently rich in alcohol and at the same 
time they must contain a bitter substance to prevent the cider 
from turning sour as soon as the conversion of the sugar is 
effected. Hence the use of fine table pears for the preparation 
of cider would be simply a waste of material. The only varie- 
ties suitable for the purpose are those which when eaten from the 
tree produce a long continued sharp heat in the throat and lie 
half a day undigested in the stomach which, however, become 
sweet by long storing and lose enough of their acerbity to be no 
longer disagreeable to the palate. In England the wild pear 
grown in hedges is generally used for the purpose. They must 
be ripe but not soft or mellow. 

In the northern part of France pear-must is sometimes used 
for the preparation of " port-wine," the taste of which is very 
much praised. The process consists in heating 50 Ibs. of must to 
176 or 185 F. and adding 5 Ibs. of raisins. At this degree of 
heat must and raisins are brought into a barrel which is tightly 
bunged and placed in a cool place. When in the course of a day 
the must is cooled to 59 or 68 F., the raisins, which are gene- 
rally put in a bag, are taken from the barrel and after bruising 
returned (but not inclosed in the bag) to the must, which is then 
allowed to ferment for 14 days. The wine is then drawn off into 
stone jugs which are well corked and sealed. 

Quince-wine. A very spicy wine can be prepared from quinces 
in the following simple manner: Place the quinces for a few 
moments in hot water and then rub them with a cloth to remove 
the down. Next 'remove the cores by means of a knife or in 
any suitable manner. Now pour hot water over the quinces 
thus prepared and boil them slowly over a moderate fire until 



356 VINEGAR, CIDER, AND FRUIT-WINES. 

soft. Then press out the juice and add white sugar in the pro- 
portion of 1J Ibs. to every 20 Ibs. of fruit. Allow the whole to 
ferment in a cool room and from time to time add some sugar- 
water during the process. Clarification and racking off is effected 
in the same manner as with cider. 



CHAPTER XXVIII. 

FRUIT-WINES. 

a. From small fruits. 

ONE of the principal objections to wine from small fruits is 
that it easily turns; this can, however, be overcome by adding, 
after fermentation is finished, 5.64 drachms of salicylic acid to 
every 100 quarts. By increasing the dose to 8.46 drachms less 
sugar can be added to the must which, of course, makes the 
beverage poorer in alcohol. A saving of sugar can be further 
effected without injury to the keeping quality of the wine by a 
suitable mixing of juices. By working, for instance, the juices of 
currants, or of raspberries by themselves, a considerable addition 
of sugar, about 1 pound per quart, has to be made, which can, 
however, be reduced one-half by mixing with a juice containing 
some bitter principle, and later on treating the wine with salicylic 
acid. Thus a large field for experimenting is opened to all, and 
only a few hints will here be given. Raspberry -juice should be 
mixed with one-quarter its volume of blackberry-juice; and in 
the preparation of currant-wine it is especially recommended to 
use four-fifths of red to one-fifth of black currants, the w T ine 
obtained being far more spicy and possessing better keeping 
qualities. Moreover, black currants used within limits are an ex- 
cellent material for improving the flavor of almost all fruit-wines. 
The flavor and keeping qualities of fruit-wine are also improved 
by throwing a couple of handfuls of crushed hazel-nuts or walnuts 
into the barrel, and also by the addition of 2 ounces, 3 drachms 
of bitter almonds, the peels of 10 lemons, 3 ounces, 5 drachms 



FRUIT-WINES. 357 

of cassia, and a few handfuls of bruised wild plums. By these 
means wine with a moderate content of alcohol acquires a strong 
taste, while its keeping quality is at the same time improved ; 
the latter can also be effected by bringing 2 ounces, 3 drachms of 
tartar into the barrel during fermentation. A few other mixtures 
of juices may be mentioned. Black berry-j nice is better adapted 
to ferment by itself than any other juice from small fruits, but 
by the addition of J- to J- its weight or its volume of strawberry- 
juice the aroma of the wine is greatly improved. Strawberry- 
juice is least suitable for fermentation by itself, and should be 
mixed with must containing a bitter principle; the addition of 
^ of the volume of the juice of the Siberian crab-apple (Pyrus 
baccata) can be highly recommended for the purpose, it being 
especially suitable for improving the keeping quality of fruit- 
wine. The juice of rhubarb stems may be added to that of 
elderberries, while the juice of gooseberries is suitable for mixing 
with that of mulberries. Moreover, a combination of several 
juices may also be used, an excellent wine being, for instance, 
prepared from equal parts of blackberry, raspberry, currant, and 
strawberry-juice, with an addition of walnuts as given above. 
In the receipts for the different varieties given below, the cus- 
tomary addition of sugar for unmixed fermentation and the 
omission of salicylic acid is retained ; it may, however, be repeated 
that with the assistance of these means the cost may be reduced 
one-half. In order to avoid repetition the following general rules 
are here given which hold good not only for the preparation of 
wine from small fruits, but also from stone-fruits. 

The fruit to be used should be sound and ripe, though not 
over-ripe, and must be freed from adhering dirt by washing in 
warm water. Large quantities are best expressed by means of 
a press while for small quantities a bag of coarse linen is sufficient 
which is kneaded and squeezed until no more juice runs out. 
Over the residue pour as much hot water as juice is obtained and 
after allowing it to stand for two hours press again and mix the 
juice obtained with the first. Now add sugar in the proportion 
of one pound to a quart of juice and bring the whole into a 
thoroughly cleansed barrel previously rinsed out with salicylated 
water. Fermentation should take place in a room having a uni- 



358 VINEGAR, CIDER, AXD FRUIT-WINES. 

form temperature of from 59 to 64 F. During this process 
lav a piece of gauze upon the open bunghole and secure it by 
means of a stone, piece of iron, etc. ; this prevents the access of 
foreign substances to the must. Every other day the barrel is 
filled up to the bung-hole with sugar-water prepared in the pro- 
portion of J Ib. of sugar to 1 quart of water. As soon as the 
" hissing' 7 in the barrel ceases bung the barrel tightly and after 
14 days draw off the contents into another barrel placed in the 
same room. After 6 months the wine can be drawn off into 
bottles, being, however, 8 days previously clarified with the whites 
of a dozen eggs or 1 oz. of isinglass slowly dissolved over a 
moderate fire in 1 pint of wine. Whatever fining is used add it 
to the wine with constant stirring. If salicylic acid is to be used 
it is best done in the manner described for cider when the wine 
has acquired the desired degree of ripeness. The bottles should 
be rinsed with salicylated water and closed with corks previously 
soaked for a few hours in hot salicylated water. Sealing the 
bottles is not necessary but in order to be sure that the corks fit 
closely shake each bottle, with the neck downwards, with the right 
hand holding the left under the cork. If the slightest moisture is 
observed, the bottles must be recorked, as carelessness in this 
respect may cause a portion of the supply of wine to spoil. The 
corked bottles are laid in the cellar. 

This general method, according to which all kinds of wine from 
small fruits can be prepared, may be supplemented by the follow- 
ing receipts: 

Currant-wine. Among all varieties of berries the currant 
contains the largest quantity of free acid, about 2 per cent., and 
comparatively little sugar, about 6 per cent. The proportion 
between these two principal constituents -is very unfavorable for 
the manufacture of wine, and currant juice fermented by itself 
would yield a product which does not deserve that name. 

Free the thoroughly ripe currant from the stems and after 
crushing press out the juice. To the residue add twice or three 
times as much water as juice obtained and after again pressing 
add the juice obtained to the first. Now examine the juice as 
to its content of acid and if necessary dilute further with water. 
Then calculate the sugar in the manner given on p. 326. Sugar 




FRUIT- WINES. 359 

and acid having been brought to the right proportion, the juice is 
allowed to ferment. 

Currant-wine is frequently prepared as a sweet liqueur-wine, 
the following directions being much used for the purpose : Juice 
100 parts, water 200, sugar 100. According to an analysis by 
Fresenius, the wine thus prepared showed after two years the 
following composition : 

Alcohol ....... 

Free acid ....... 

Sugar ....... 

Water 

100.00 

According to another receipt, 17^ Ibs. of thoroughly ripe cur- 
rants freed from the stems are bruised in a wooden vessel Avith 
the addition of 3J quarts of water. The paste thus obtained is 
gradually brought into a bag of coarse linen, which is laid upon 
an oblique board, and pressed out by means of a rolling-pin. 
The press-residues are returned to the wooden vessel and, after 
adding 7 quarts of water, thoroughly worked with a pestle, and 
then again pressed in the above manner. The juice thus ob- 
tained is brought into a barrel having a capacity of 34J quarts, 
a solution of 12 Ibs. of sugar in 14 quarts of water is then added, 
and finally sufficient water to fill up the barrel to within 3 inches 
of the bung. After covering the bung-hole with a piece of 
gauze, the whole is allowed to ferment in a room having a tem- 
perature of from 59 to 64 F. When the principal fermenta- 
tion is over the barrel is entirely filled with water and closed 
with a cotton bung. The wine is then allowed to further fer- 
ment for 6 months in a cellar having a temperature of from 54 
to 59 F., when it is drawn off into another barrel or into bottles. 
By adding to the fermenting juice ^ Ib. of comminuted raisin 
stems a product closely resembling Tokay-wine is obtained. 

A very strong beverage is obtained by adding to the expressed 
juice of currants twice the quantity of water and stirring in 2 
tablespoonfuls of yeast. Allow the juice to ferment for 2 days, 
then strain it through a hair-sieve, and after adding 1 Ib. of sugar 
for every quart, allow it to ferment. When fermentation is nearly 
finished add French brandy in the proportion of 1 quart to 40 



3t>0 VINEGAR, CIDER, AND FRUIT- WINES. 

quarts of the juice, and bung up the barrel two days later. The 
wine is ripe in four months. 

According to another receipt the currants, separated from the 
stems, are pressed and the juice mixed with an equal quantity of 
water. Then add to each gallon of liquid 2 J Ibs. of sugar, 2 ozs. 
of cream of tartar, and 1 oz. of pulverized nutmegs, with 1 quart 
of alcohol. Allow the whole to ferment, then fine with isinglass, 
draw off and bottle. 

Another method is to express all the juice possible, then take 
an equal amount of boiling water, and pour on the pressed fruit ; 
let it stand for 2 hours, squeeze out as much as there is of juice 
and mix ; then add 4 Ibs. of brown sugar to each gallon of the 
mixture ; let it stand for 3 or 4 weeks, until fairly worked, with 
the bung out, and when it is done working, bung it up, then 
place it in a cool cellar. 

Strawberry-wine. For the preparation of wine very fragrant 
strawberries should be selected. The aroma of the strawberry is 
so delicate that it readily undergoes a change and soon disappears 
entirely. Hence to secure it and transfer it into the juice the 
strawberry requires special treatment, whereby neither the con- 
tent of acid nor that of sugar is taken into consideration. This 
treatment consists in mixing the sound, ripe berries, without pre- 
vious crushing or bruising, with the same weight of pulverized 
sugar and allowing the mixture to stand in a glass or stoneware 
vessel in a cool place until all the sugar is dissolved to a clear 
syrup in which the shrunk and tasteless berries float. To sepa- 
rate the latter, strain the juice through a woollen cloth previously 
rinsed with some lemon-juice or tartaric acid, dilute with the 
same quantity of water, bring the acid to 0.5 per cent., and sub- 
ject the whole to fermentation in the usual manner at a tempera- 
ture of from 50 to 59 F. 

Some allow the berries to ferment with the juice, but the wine 
obtained is somewhat harsh and not as delicate. 

By finally adding to the finished wine from 4 to 5 per cent, of 
rock-candy, a liqueur- wine is obtained which, as regards aroma, 
cannot be surpassed and is especially liked by ladies. 

Excellent strawberry-wine is also obtained according to the 
following directions : Press out 10 Ibs. of different varieties of 



FRUIT-WINES. 361 

small and large cultivated strawberries, which give about 2^- 
quarts of juice. Pour water over the residue and press again, so 
as to obtain about 3 quarts more of juice or a total of 5J quarts. 
Xext dissolve 4 pounds of rock-candy in 5 quarts of cold water, 
bring the solution, together with the 5J quarts of juice, into a 
small cask, and allow the whole to ferment in a cellar having a 
temperature of 61 F. In four weeks the wine is ready for draw- 
ing off into bottles. It is of a beautiful pale yellow color and 
possesses an excellent bouquet, and if made sparkling furnishes 
an excellent beverage. 

According to a receipt in the " Weinzeituug," 40 quarts of 
strawberries and 41 quarts of water, with an addition of 12 Ibs. 
of sugar, 3 J ozs. of tartar, and a gallon of whiskey free from fusel 
oil are allowed to ferment and the resulting wine is treated in the 
usual manner. 

Another method is to pour 1 quart of hot water upon 1 quart 
of crushed strawberries and pressing out after allowing the mass 
to stand for 2 days. Then add to every quart of juice 1 Ib. of 
sugar, and to every 40 quarts of juice the grated peel and juice 
of 2 lemons and 2 oranges and 4 quarts of French brandy. 
Allow the whole to ferment, and treat the resulting wine in the 
usual manner. 

Gooseberry-wine. The proportion between sugar and acid is 
somewhat more favorable in the gooseberry than in the currant, 
but not sufficiently so as that the pure juice would yield a good 
wine by fermentation. Hence the juice must be converted into 
suitable must, as regards sugar and acid, in accordance with the 
rules given on p. 325. The yellow varieties are preferable, they 
alone having a distinctly vinous taste ; the wine obtained from 
the red and green varieties is somewhat insipid. The juice is ob- 
tained in the same manner as from currants, the berries being 
bruised, the juice allowed to run off and the residue washed sev- 
eral times with water, so that each volume of juice receives an 
addition of 1 volume of water, though as the mixed juice has to 
be tested as to its content of acid, the direction in regard to the 
addition of water need not be accurately followed. The must 
may contain as much as 30 per cent., because the fermentation 
of gooseberry-must is generally carried on in the warmer season 



362 VINEGAR, CIDER, AND FRUIT- WINES. 

of the year, so that all or the greater portion of the sugar fer- 
ments and the wine, on account of the quantity of alcohol formed, 
Avill keep for an almost indefinite time. Gooseberry-wine made 
from must rich in sugar generally acquires by age an odor of 
Madeira-wine, which frequently deceives even connoisseurs. 

Gooseberry-wine like currant-wine being liked sweet, a larger 
quantity of sugar may be added to the must from the start though 
for a quicker progress of fermentation it is better to add the 
desired quantity of sugar to the fermented wine; if the must has 
been made quite sweet so that a wine rich in alcohol is formed no 
fear need be had of the wine fermenting anew on account of the 
addition of sugar. 

There are a number of receipts for the preparation of gooseberry- 
wine, but when more closely examined the products prepared 
according to them will be found either more or less rich in alcohol 
or to contain more or less free acid and be either sweet or not 
sweet, so that the proportion can evidently be changed in any 
manner desired. It is further evident that nothing is gained 
thereby as regards quality, because the type for all artificial wines 
is grape-wine obtained in a good season. In such wines the pro- 
portions between alcohol and free acid are well known and within 
such narrow limits that they cannot be essentially exceeded on 
either side, and they alone can serve as a basis for the rational prepa- 
ration of gooseberry-wine as well as of all artificial wines. With 
the aroma or bouquet which is to be imparted to such wine it 
is, of course, different, but no special directions are required as 
every one manages it according to his own taste or according 
to that of those who buy and drink the wine. Thus, it is also 
with the addition of sugar; one likes a sweet wine, the other one 
less sweet and the third one without any sugar. The principle 
aim is to prepare a wine which contains the necessary quantity of 
alcohol to insure its keeping properly, and the power of resistance 
against decomposing influences and from which the greater por- 
tion of the fermenting substances is removed by fermentation. 
In most cases the natural conditions are of great use in this respect, 
for in order to decrease the content of free acid it becomes neces- 
sary to dilute the fruit juices whereby the quantity of fermenting 
substances is also relatively decreased, and sometimes even to such 



FRUIT-WINES. 363 

an extent that they do not suffice for the complete fermentation of 
the sugar. Such wine, if not wanting in alcohol, will keep for an 
almost indefinite time and may be exposed to the access of air and 
a high temperature without the appearance of the formation of 
acetic acid. 

Gooseberry-champagne. The taste of this beverage closely 
resembles that of genuine champagne. There are several modes 
of its fabrication. In France a light wine which does not contain 
too many fermenting substances is used. Somewhat less than 2 
per cent, of sugar, or about 15 grammes to a bottle of 800 cubic 
centimetres 7 capacity, is dissolved in the wine and the latter drawn 
off into strong champagne bottles which are then hermetically 
corked and tied with twine. The wine is then allowed to fer- 
ment in a room having a temperature of from 77 to 99 F. 
When fermentation is finished, the bottles are brought into a cool 
cellar and placed first horizontally and then gradually bottom 
uppermost so that the yeast may collect on the cork and the wine 
become clear. When all the yeast is precipitated to the neck of the 
bottle, the sediment is carefully removed degorgie as it is termed 
by first raising the string securing the cork and then the latter, 
the bottle being held in a horizontal position. The cork being no 
longer held by the string is forced out together with the deposit 
of yeast while the clear wine impregnated with carbonic acid 
remains behind. To prevent the unavoidable loss of wine, the 
cork together with the yeast and wine forced out is collected in 
an upright barrel with a large aperture towards which the mouth 
of the bottle is held during the operation. 

The wine thus impregnated with carbonic acid, however, is not 
yet champagne ; it only becomes so after the addition of a solution 
of fine rock candy in brandy with which the bottle is filled up. 
Each bottle after receiving the necessary quantity of the solution, 
or liqueur as it is termed, is at once closed with a cork which is 
secured with twine or wire. Removing the deposit of yeast is the 
most difficult portion of this operation, long experience being 
required before the workman possesses the necessary skill. 

According to another method, which is also called the impreg- 
nating method, the sugar required for sweetening is dissolved in 
the wine, and after clarifying the solution by filtering through 



364 VINEGAR, CIDER, AND FRUIT-WINES. 

paper pulp in a bag, or, if necessary, with some isinglass, it is 
taken to the impregnating apparatus, one similar to that used for 
mineral water answering the purpose. The wine is then saturated 
under a pressure of 4J to 5 atmospheres with the desired quantity 
of carbonic acid and at once drawn off into bottles, which are 
corked and wired as above. 

The advantage of this method consists in the rapidity with 
which champagne can be made, 30 to 36 months being required 
for the first method before the champagne is ready for transporta- 
tion. 

The following method is the most simple of all, but does not 
yield as fine a product. Each bottle is finished by itself and no 
special apparatus is required. The wine is sweetened and clari- 
fied in the same manner as in the impregnating method and then 
drawn off into bottles. In case the wine is not rich enough in 
alcohol, the content of the latter may be increased by 10 per 
cent. 

After having filled the bottles about 1.52 cubic inches less 
than generally, add first to each bottle 11 drachms of pure crys- 
tallized bicarbonate of potash and immediately afterwards 1 oz. 
of pure crystallized tartaric acid in pieces. Then close the bottle 
with the cork and secure the latter by tying or wiring it cross- 
wise. The potash and acid are now brought to solution by gently 
swinging the bottle to and fro, the contents becoming at the same 
time turbid by the separation of bitartrate of potash. By 
placing the bottle bottom upwards the separated tartar is collected 
as much as possible upon the lower surface of the cork and after 
the wine is clear removed in the same manner as described in the 
first method. It is not absolutely necessary to remove all the tar- 
tar as it settles on the bottom and the champagne will pour out 
clear. 

According to any of these methods all fruit-wines can be con- 
verted into champagne or sparkling wines. 

Semler gives the following directions for the preparation of 
gooseberry-champagne. Pour 20 quarts of warm water over 20 
quarts of crushed gooseberries and add 6 Ibs. of sugar, 4J Ibs. of 
honey, 1 oz. of pulverized tartar, J oz. of dried lemon peel, and J 
oz. of dried orange peel. After standing for two days strain the 



FRUIT-WINES. 365 

mixture through a hair-sieve into a barrel and add 2 quarts of 
French brandy. When the " hissing" in the barrel ceases clarify 
the wine and after a few days draw it oif into bottles securing the 
corks with wire. Before filling the bottles throw a piece of sugar 
and J drachm of bicarbonate of soda into each. 

Raspberry-wine. Raspberries have such an agreeable and re- 
freshing taste and odor that while they are not very sweet and 
the proportion of acid to sugar is not very favorable they are 
great favorites. Their aroma passes into the wine and would be 
even too predominant if for the preparation of wine the juice had 
not to be strongly diluted with water in order to decrease the 
acid. 

As in all other fruit, the quality of the raspberry depends on 
the weather, and when this is favorable during the time of the de- 
velopment and maturing of the fruit, the latter is sweet and pala- 
table, but in cold and wet seasons sour and harsh. No other 
fruit suffers as much from such conditions as the raspberry. 

We have the wild and cultivated raspberry. The wild rasp- 
berry is smaller than the cultivated but possesses a stronger aroma ; 
unfortunately it is too frequently infested with the larva of many 
insects to render it always palatable. The cultivated raspberry 
is considerably larger, and is less attacked by worms, but pos- 
sesses less aroma and is frequently even watery. 

To obtain the juice for the preparation of wine the thoroughly 
ripe raspberries are crushed to a paste in a wooden tub by means 
of a wooden pestle. To separate the grains the paste is forced 
through a fine wire sieve, which, in order to protect it from the acid, 
is best provided with a coat of asphalt or shellac varnish. It is, 
however, no disadvantage to allow the grains to ferment with the 
pulp, some tannin being thereby introduced into the wine which 
under certain circumstances may be even desirable. 

The content of acid in the raspberry varying considerably in 
different years, a test of the juice in this respect becomes abso- 
lutely necessary in order to enable one to dilute it in the correct 
proportion with water. For this purpose press out a small 
quantity of the crushed raspberries and determine the acid in the 
manner given on p. 325. The sugar contained in the raspberry 
need not be taken into consideration, since by dilution it is 



366 VINEGAR, CIDER, AND FRUIT-WINES. 

reduced to 1 per cent, and still less. The must is simply brought 
up to 25 per cent, of fruit-sugar and allowed to ferment in the 
usual manner. The treatment of the wine after fermentation is 
the same as for other fruit-wines. 

Blackberry-wine is prepared in the same manner as raspberry- 
wine. Of the numerous directions for its preparation we give the 
following : Gather the berries on a dry day, crush them with the 
hand into a kettle, and add just enough hot water to cover the 
mass. Then add a handful of bruised raisins and a handful of 
strawberry leaves, from the heart of the mother plant, or, still 
better, from the suckers, and allow the mass to stand for four days, 
when a crust of yeast will have formed on the surface. The mass 
is now pressed out and sugar in the proportion of 1 pound to every 
4 quarts added. Fermentation is allowed to go on for two weeks ; 
the barrel is then bunged up and the wine drawn off after six 
months. During fermentation, and especially in the beginning 
of it, care must be had to fill up the barrel. 

To make from blackberries a beverage resembling port-wine 
the following method is recommended : Press out the juice and 
allow it to stand for 36 hours. While fermenting during this 
time remove all scum from the surface. Now add one-fourth the 
quantity of juice, of water, and 3 pounds of brown sugar to 
every 4 quarts of fluid and filter after 12 hours. Fermentation, 
which requires but a few days, being finished, bung up the barrel 
tightly and after six months draw off the wine. The latter im- 
proves by age. 

Mulberry-wine. Press the juice from the fruit, dilute with the 
same quantity of water, add 1 pound of sugar for every quart of 
liquid, and boil the whole J hour. Then add for every 100 
quarts 3 quarts of alcohol, 6 J ounces of tartar, 1 ounce of cassia, 
and \ ounce of bruised bitter almonds, and allow the whole to 
ferment. The further treatment of the wine is the same as for 
other fruit-wines. 

Elderberry-wine. Boil equal quantities of berries and water 
one-half hour, pour the whole into a hair-sieve, press the pulpy 
portion of the berries gently through with the hand and remove 
the residue. Compound the strained juice with sugar in the pro- 
portion of J pound to 1 quart and boil 20 minutes. As soon as 



FRUIT- WINES. 3G7 

cool bring it into a barrel to ferment. Fermentation being 
finished paste stiff brown paper over the bung-hole, and after 
eight weeks draw off the wine into bottles. 

Another method is to boil 50 quarts of water, 10 quarts of 
elderberries, 40 pounds of sugar, 5 ounces of pulverized ginger, 

and 2^ ounces of cloves for 1 hour, with constant skimming". 

- & 

Then bring the liquid together with 4 pounds of crushed raisins 
into a barrel and allow it to ferment. At the termination of the 
fermentation it will yield a wine similar to the Cypria or Greek- 
wine. 

Juniperberry-wine. 70 quarts of water, 35 pounds of crushed 
raisins, 10 quarts of juniperberries, 4 ounces of tartar, 1 quart of 
French brandy, and a handful of fresh marjoram leaves are 
brought into a barrel and the mixture is allowed to ferment for 
12 hours. 

Rhubarb-wine. Add to every 5 pounds of the thinly-sliced 
stalks 2| quarts of soft water and bring the whole into a clean 
wooden vessel. Cover the latter and stir the contents with a 
wooden stick three times daily for one week. Then pass the fluid 
through a wide-meshed sieve and add to every 3 quarts 4 pounds 
of white sugar, the juice of 2 lemons, and the peel of 1 lemon 
rubbed upon sugar. Allow the mixture to ferment in a barrel, 
and after clarifying draw the wine off into bottles in March. 

The variety of rhubarb, known as Victoria, is best adapted 
for the preparation of wine which can also be effected according 
to the following directions : Cut up the stalks and express the 
juice. To every gallon of juice add 1 gallon of soft water and 7 
pounds of brown sugar. Bring the mixture into a barrel and 
allow it to ferment until clear with the bung out, keeping the 
barrel filled with sweetened water as it works over, then bung 
the barrel tightly or draw the wine off into bottles. It makes an 
agreeable and healthful wine, affording a good profit, as nearly 
1800 gallons of wine may be obtained from each acre of well- 
cultivated plants. The stalks will furnish about three-fourths 
their weight in juice. 

Tomato-wine. Press out the juice from ripe tomatoes, add to 
each quart of it 1 pound of brown sugar, and allow the whole to 



368 VINEGAR, CIDER, AND FRUIT-WINES. 

ferment. After three months the wine can be drawn off into 
bottles. 

Parsnip-wine. Cut 12 pounds of parsnips into thin pieces, add 
15 quarts of water and boil until soft. Then press out the juice 
and after straining through a hair-sieve sweeten with f pound of 
sugar per quart. After again boiling for j hour it is brought, 
when cold, into a barrel and a tablespoonful of yeast is added. 
Stir the juice daily for 10 days then bung up the barrel tightly 
and after six months draw off the wine into bottles. 

In the same manner wine may be prepared from carrots, clover- 
heads, corn-stalks, etc. It is, however, recommended to add to the 
juice some aromatic substance such as a handful of marjoram, 
almonds, plum-kernels, currants, walnuts, ginger, or still better a 
few quarts of black currant juice. 

^ 
b. From Stone-Fruits. 

Cherry-wine. Stone sweet cherries and after crushing the pulp 
to a paste allow it to ferment in stoneware pots for 12 hours. 
Then press out the juice which is returned to the pots and allowed 
to stand until yeast fungi rise to the surface. Now add 1 pound 
of sugar to every 3 quarts of must, bring the latter into a barrel 
and allow it to ferment 8 days. Then rack the wine into bottles 
and keep in a cool place. The preceding is the method followed 
in England where pure cherry-wine is made. It may, however, 
be remarked that it is somewhat insipid. A mixture of the juice 
of cherries with that of the raspberry or currant can, however, 
be highly recommended, it yielding a beverage similar to port- 
wine. It is an American receipt and much preferable to the 
English. Press the freshly gathered cherries, black or red, but 
selecting those with the softest pulp, without crushing the stones. 
To the juice obtained add one-eighth of its quantity each of rasp- 
berry and black currant juice and sweeten with lump sugar in 
the proportion of 1 pound to 2J quarts of juice. The whole is 
then brought into a barrel to ferment. When fermentation is 
finished close the barrel tight and allow it to rest for three months. 
Then clarify the wine and draw it off into bottles. It is fit to 
drink in six weeks. 



FRUIT-WINES. 369 

Morello-wine. Press 60 pounds of morellos so as to crush the 
stones, mix the juice obtained with 20 quarts of sherry-wine and 
the same quantity of warm water, and bring the whole into a 
barrel to ferment. Suspend in the barrel a bag containing 1J 
ounce each of cinnamon, powdered nutmeg, and mace, allowing 
it to remain until drawing off the wine. The latter is very pala- 
table in two months after fermentation is finished. 

Plum-ivine. Not all varieties of plums are suitable for the 
preparation of wine, but the Reine Claude and Mirabelle can be 
highly recommended, the latter especially making as spicy and 
agreeable wine as any variety of fruit. With the almost innu- 
merable varieties of plums it is not possible to say which are suita- 
ble for the preparation of wine, and which are not. It can only 
be determined by experiment, though right sweet varieties only 
should be chosen. In this country the small sweet variety known 
as the wheat-plum, etc., is frequently used for the purpose. The 
process is as follows : Stone the plums, then bruise the pulp, and 
add to every 8 pounds of the latter 3 quarts of hot water. After 
2 days press out the juice and add to every 2 quarts of it one 
pound of sugar. Now bring the juice into a barrel in a cool room 
and add the crushed kernels of ^ of the stones. Allow the whole 
to ferment completely. After 12 months the wine is clarified and 
drawn oif into bottles, each of which receives a small piece of 
sugar, which improves the keeping quality of the wine. 

Apricot and peach-wines. Both these varieties are used when 
nearly ripe. Remove the stones and crush the pulp to a paste. 
For every 8 pounds of the latter add 1 quart of fresh soft water, 
and let the mass stand 24 hours. Then press out the juice, add 
for every 2 quarts of it 1 pound of sugar, and allow it to ferment. 
During fermentation it is recommended to throw a handful of the 
crushed stones into the barrel, which gives to the product a more 
spicy flavor. 

Sloe or wild plum-wine. This beverage is not to be despised if 
prepared in the manner given for plum-wine. The sloes must, 
however, remain on the bushes until after the first frost, which 
sweetens them. 
24 



PART III. 

CANNING AND EVAPORATING OF FRUIT, MANUFAC- 
TURE OF CATCHUPS, FRUIT-BUTTERS, MARMA- 
LADES, JELLIES, PICKLES, AND MUSTARDS. 



CHAPTER XXIX. 

PRESERVATION OF FRUIT. 

THE use of hermetically closed tin cans is the only method for 
preserving fruit which has become of commercial importance. 
Before discussing it, the various ways which have proved more 
or less satisfactory for household purposes will be briefly men- 
tioned. The following rules apply, however, to all methods : 

1. The fruit must be gathered in dry weather and when free 
from dew ; it is to be kept as free from dust as possible. 

2. Absolutely sound fruit, not over-ripe, should only be se- 
lected. 

3. The fruit should be preserved immediately after gathering. 

4. The utensils used must be kept scrupulously clean. 

5. The preserving vessels should not be placed directly upon 
the fire. 

6. A good quality of white sugar only should be used ; brown 
sugar injures the taste and color of the fruit. 

7. Copper or brass kettles alone should be used for boiling, if 
the latter is not effected in glass ; the spoons should be of wood or 
of bone. 

8. The jars or cans should be thoroughly rinsed best with sali- 
cylated water, and if corks are to be used they should be perfectly 
sound and scalded in hot water to which some salicylic acid has 
been added. 

9. Small jars or cans are preferable to large ones, and they 
should be kept in a dark, cool, dry place. 



372 VLNEGAR, CIDER, AND FRUIT-WINES. 

We will first mention the old French method, known as au 
Baine-Marie, which, on account of its simplicity, is still much 
used. Berries require no preparation, but peaches, apricots, and 
plums must be stoned and halved, and cherries and small plums 
stoned. Apples and pears are peeled and quartered and imme- 
diately thrown into boiling water for 4 minutes to bleach. They 
are then laid a few minutes upon a sieve to dry, and brought, like 
other fruit by means of a spoon into wide-necked glass jars which 
are filled to within 2 inches of the edge. In placing the fruit in 
the jar press it well together. The empty space is then filled up 
with hot syrup composed of 2 parts of sugar and 1 part of water, 
and the jars, after heating them somewhat upon a stove, are placed 
in boiling water for 8 minutes for kernel fruit and for 10 minutes 
for stone fruit or berries. The jars are then immediately corked 
and sealed. 

According to another French method, the flesh of the fruit is 
preserved without boiling. Stone-fruits and berries only can be 
used. The fruit is pressed through a hair-sieve and the pulp 
mixed with an equal weight of pulverized sugar. The mixture 
is then brought into glass bottles which are corked and sealed. 
This fruit-pulp keeps, however, only through the winter, or if 
kept in a cold place or in a refrigerator. 

The following method gives better satisfaction : The fruit, such 
as cherries, berries, plums, peaches, apricots, etc., is, without the 
addition of water, brought into wide-necked glass jars in such a 
manner that a layer of fruit alternates with a layer of sugar, the 
top layer being sugar. The jars are then tied up with salicylated 
parchment paper, placed in a water-bath, and the water kept 
boiling for 15 to 30 minutes, according to the variety of fruit, 
small fruit requiring less time than large, and berries only about 
15 minutes. The jars are then stored in a cool, dark place. 
For closing jars with narrow mouths corks are preferable. They 
are soaked in hot salicylated water and sealed. 

Fruit thus preserved retains its fresh, natural appearance and 
keeps for a considerable time. If appearance is, however, of 
secondary consideration, it is better to boil the fruit, as is done 
with kernel-fruit, melons, and all large varieties. The prepara- 
tion for this method varies according to the nature of the fruit. 



PRESERVATION OF FRUIT. 373 

Apples and pears must be peeled, and, if not too large, only cored, 
otherwise they have to be halved or quartered. Melons are 
peeled and cut into strips. Quinces are steamed until soft, then 
peeled as clean as possible, quartered, and the cores removed. 
After this preparation the fruit is brought into the preserving 
kettle and as much water as is necessary for boiling added. 
Boiling should be done very slowly and continued until the fruit 
commences to get soft. It should not be boiled too soft, but only 
sufficiently to enable it to absorb the sugar-liquor. When this is 
the case the fruit is taken from the fire and strained ; with the 
liquor a syrup of the following composition is prepared : For 
each pound of fruit take one pound of sugar and soak it in ^ 
pint of the liquor. It is then placed upon the fire and the re- 
sulting syrup skimmed. When it boils the fruit is introduced 
and slowly boiled, or rather simmered, because it must not fall to 
pieces, for five to ten minutes, according to its softer or harder 
nature. The fruit while still warm is then brought into the jars 
in which no vacuum must remain. Hence they must be filled up 
to the cork, or, if bladder or parchment paper is used, for closing 
them up to the rim. In the latter case it is advisable to place 
upon the surface a close-fitting piece of paper, previously satu- 
rated with a concentrated solution of salicylic acid in rum. Cur- 
rants, barberries, and grapes are sometimes preserved in their 
natural clusters. They are first washed in fresh water, then 
slowly boiled soft, and strained. With the liquor a syrup of the 
previously mentioned composition is prepared, which is boiled 
and skimmed and poured upon the fruit in the jars. 

Fine table pears are sometimes preserved in the following 
manner : 8 large pears are placed in a syrup prepared from 6 
ounces of sugar, 3 ounces each of cloves and allspice, J pint of 
water, and J pint of port-wine or other sweet red wine. In this 
syrup they are boiled very slowly as much as 3 hours until 
soft, and, while still warm, are brought together with the syrup 
into jars, which are treated in the manner previously described. 
By taking equal parts of pears and of fine plums a very beautiful 
product is obtained. 

The boiling down of fruit in large stoneware pots is frequently 
accompanied by mishaps, and is more and more superseded by 



374 VINEGAR, CIDER, AND FRUIT-WINES. ' 

other methods. It consists in dissolving J to J pound of sugar 
in water and boiling the resulting syrup together with the fruit 
until the whole forms a jelly-like mass. While still warm the 
pots, which must be full, are tied up with bladder. A piece of 
salicylated paper should be placed upon the surface of the fruit 
before tying up the pots. 

Preserving in Air- Tight Cans. 

This method, as previously mentioned, is the only one which 
has become of commercial importance ; for the United States 
and England it has even become of the same national import- 
ance as the fabrication of beet-sugar for France and Germany. 
The number of factories, briefly termed canneries, in both the 
countries named, has largely increased during the last few years, 
and not a few of them employ 1000 hands during the fall. Of 
course these factories do not limit themselves to the canning of 
fruit, as otherwise they would have to cease operations during 
the winter months, but that branch of the business preponderates 
over all others. The search after other suitable material is con- 
stantly more extended, and it is difficult to tell what may not be 
canned in the future. The trade-list of a large English factory 
now contains 200 different articles ; it includes, however, all 
Southern fruits, a portion of which is, singularly enough, returned 
in this state to the tropics. The American trade-lists embrace, 
as a rule, three groups, viz : 

1. Apples, pears, peaches, apricots, plums, strawberries, rasp- 
berries, blackberries, currants, cranberries, whortleberries, necta- 
rines, grapes, cherries, quinces, cocoanuts, pineapples, marmalade, 
jelly, green walnuts. 

2. Peas, beans, beans with pork, corn, tomatoes, asparagus, 
carrots, onions, pickles, cauliflower, horseradish, mushrooms, 
catchups, succotash, plum-pudding, sweet potatoes. 

3. All kinds of poultry, venison, salmon, lobster, crawfish, 
oysters, crabs, beef, mutton, pork, eels, salt-water fish, ham, pig's 
feet, beef tongue, lamb's tongue, frog legs, mussels, etc. 

All the varieties of fruit named in the first group being not 
equally well adapted for canning, the less suitable kinds are only 



PRESERVATION OF FRUIT. 375 

used in small quantities. Plums and cherries have up to the 
present time caused the greatest difficulty, because for economy's 
sake they were canned without removing the stones, in which the 
germ had to be destroyed by the application of a high degree of 
heat. When this was omitted the contents of the cans would 
spoil as soon as shipped to warm countries, in consequence of the 
germination of the stones. If, on the other hand, the cans were 
sufficiently heated, the plums or cherries would fall to pieces, and 
in this pasty condition were unsaleable in many markets, for in- 
stance in England. To overcome this evil the manufacturers 
have recently commenced to stone these varieties of fruit as well 
as peaches and apricots. It may here be remarked that both 
plums and cherries are comparatively dear in the United States, 
the cause of their not thriving well being partially due to the 
climate and partially to numerous enemies. Heart-cherries, 
black raspberries, and whortleberries are the worst varieties of 
fruit for canning, as they lose their agreeable taste by steaming. 
Strawberries also become somewhat insipid, but red raspberries 
are excellent provided they are canned as soon as possible after 
being gathered. Blackberries are not quite so good, though, if 
brought into the can immediately when plucked, they furnish an 
agreeable dish. Currants have too many seeds, and are better 
used for jelly. Black currants are well suited for canning, and 
in this state are much used by bakers for tarts. Gooseberries 
canned before entirely ripe are very good. Among the smaller 
stone fruit the Mazard cherry has few superiors ; if carefully 
canned, it retains its shape, color, and aroma as on the tree. 
Most. plums are suitable for canning, provided they are stoned. 
Among the kernel fruits the quince occupies the first rank, as 
it is the only variety of fruit which gains by steaming. Pears 
are very suitable for canning, as even the inferior qualities can 
be used for the purpose. Apples, however, must be carefully 
selected, and only sweet varieties with firm flesh should be used ; 
the Siberian crab-apples can be highly recommended for the pur- 
pose. 

As a general rule, fruit for canning should have a firm flesh 
and fine aroma. We find these conditions in all the varieties 
preferred by the North American factories, whose canned goods 
can be found in every large city of the world. The peaches are 



376 VINEGAR, CIDER, AND FRUIT-WINES. 

of the early and late Crawford* varieties, and the apricots Moor- 
parks. Among plums we find the following varieties : Washing- 
ton, Columbia, Reine Claude, Coe's golden drop, yellow gage. 
Royal Ann is the favorite variety of cherries, though the differ- 
ent varieties of Bigareans and the black Tartarian heart-cherry 
are also used. Muscat, Muscat Alexandria, and Malaga are the 
favorite varieties of grapes. Among apples the Newtown pippin 
is pre-eminent ; it is considered one of the finest apples in this 
country. Several varieties of pears are highly esteemed in the 
Eastern States for canning purposes, but in California the Bart- 
lett pear is almost exclusively used. With this pear the Califor- 
nian packers say they have conquered the foreign markets, and 
they will not risk their reputation by abandoning it. 

Next to the variety of fruit the cans are of the greatest import- 
ance. Much has been said and written in regard to them, and 
the discussion pro and con will very likely be continued until a 
new and important improvement is discovered. And it is actu- 
ally necessary that the inventors should set their wits to work 
for the production of a can which would overcome all complaints, 
as thereby they could create a beneficial revolution in the fruit 
industry. The well-known patent cans are excluded from use on 
a large scale on account of their high price. Glass jars have some 
advantages : they are comparatively cheap, allow of an inspection 
of their contents, and the ready recognition of a leak, and are not 
attacked by the vegetable acid. But, nevertheless, they have not 
been introduced into general use because they are liable to break, 
and, being heavy, increase the cost of transportation, and, finally, 
it is difficult to close them air-tight. The sealing of a bottle with 
a narrow mouth is quite a different thing from sealing one with an 
aperture three inches in diameter. It may do for pickles, marma- 
lade, or jelly, but for preserved fruits which are to be transported 
long distances it cannot be depended on. The same objections 
may be made to stoneware jars, which possess the further disad- 
vantage that their contents cannot be inspected and a leak is dif- 
ficult to discover. Nevertheless, they are used by some large 
English factories for the reason, it is claimed, of keeping their 

* The name given to each fruit is the recognized name of the American 
Pomological Society as far as recorded in their catalogue. 



PRESERVATION OF FRUIT. 377 

products free from influences deleterious to health. To facilitate 
sealing the jars are generally small of about one pound capacity. 
Tin cans have many defects, but their use is very extensive, and 
in the United States they are almost exclusively employed. In 
California they are manufactured of a size that, when filled, they 
weigh 2J Ibs., while in the Eastern States, as well as in England, 
they weigh, filled, only 2 Ibs. Complaint has been frequently 
made that the use of tin cans is deleterious to health because they 
contain lead, which is dissolved by the vegetable acid and trans- 
ferred to the fruit-syrup. In reply it has been said that only the 
inferior qualities of tin contain lead, and that only in an infini- 
tesimal quantity ; but it cannot be denied that the solder may 
readily become injurious to health, and in cases of poisoning ex- 
amined in the United States and in England, it could every time 
be shown that the respective cans were soldered on the inside. 
In England, if we are correctly informed, soldering the cans in- 
side is now prohibited, and the passage of a similar law in the 
United States is agitated. At any rate the time is very likely 
not very distant when such soldering will be entirely done away 
w T ith, if only for competitive reasons. To completely overcome 
all complaints against solder, as well as against a content of lead 
in the tin, cans are now manufactured in England which are pro- 
vided inside with a thin coating whereby the contents are pro- 
tected from contact with the metal. The insoluble constituent of" 
this coating consists of silicate of lime or glass-powder previously 
treated with hydrofluoric acid, while the soluble constituent is 
silicate of soda or of potash. Any silicate of earthy bases or 
metals may be used, or a precipitated gelatinous silicate. The 
alkali is fixed or removed by means of a bath containing a dilute 
solution of hydrofluosilicic acid, or a dilute solution with any other 
suitable acid. For preparing the composition mix the soluble 
with the insoluble silicate. The tin plates are coated with this 
mixture by means of a brush, or dipped in a bath of it and then 
dried by heat. The plates thus acquire a glass-like coating, 
which remains fixed no matter IIOAV the plates may be handled 
and worked.* 

* In this country some packers of lobsters, shrimps, etc., line the cans with 
parchment paper. 



378 VINEGAR, CIDER, AND FRUIT-WINES. 

In the canneries in the United States the cans are manufacured 
in a special department, and the division of labor is carried so far 
that every can passes through eight hands before it is finished ; 
but only with such a system is it possible to turn out large quan- 
tities in an incredibly short time. This far-reaching division of 
labor is, however, not limited to this department alone, but is the 
supreme law in the entire establishment. In the same department 
the solder is cut by a machine into small three-cornered pieces. 
Each workman receives a certain quantity by weight of solder 
and of charcoal with which he is expected to solder a certain 
number of cans. The workmen are paid by the piece, and each 
solderer has a number which is stamped in every can he solders, 
so that those which prove leaky may be returned to him for repair. 
By this system there is no waste of material, and the leaky cans 
do not exceed 5 in 1000. 

In another department the fruit is carefully inspected on long 
tables ; the unsound is thrown out, and the sound turned over to 
the peelers and stoners, who of course work with the most im- 
proved machines. There are carriers bringing uninterruptedly 
fresh fruit and off-bearers removing and sorting the waste. 
^Nothing is thrown away, the waste being used partially in the 
manufacture of jelly and partially in distilling ; even the stones 
are utilized, as they are sold either to nurserymen or to chemical 
factories. Other workmen are occupied in placing the peeled and 
stoned fruit in the cans, which are handed over to boys, who place 
them upon small trucks running upon rails and transport them 
to the department where the filling in takes place. In the same 
department the syrup of sugar and water is prepared, but if the 
proportion of composition were asked a different answer would 
be received in every cannery. In regard to this point every 
manufacturer has his own ideas, which also extend to modifications 
for the different varieties of fruit. One factory we know of did 
not use any syrup whatever. The fruit was simply pressed quite 
tight into the can, and had to depend on its own juice. The fruit 
retained its natural color, taste, and aroma better than with the 
use of syrup, but the important question whether its keeping 
quality was equally good we are unfortunately not able to answer. 
All manufacturers agree, however, that the best quality of white 



PRESERVATION OF FRUIT. 379 

sugar should be used for light-colored fruits, and light brown 
sugar for dark-colored, and that the syrup must be perfectly clear, 
and, hence, very carefully skimmed in boiling. In most factories 
the syrup used consists of 1 Ib. of sugar dissolved in 1 pint of 
water. The filling of the cans with the fruit and syrup, the latter 
being generally kept warm, is effected with the assistance of a 
scale, so that each can has exactly the weight upon which the 
selling price is based. The caps previously provided with a hole 
the size of a small pea are then soldered upon the cans. The hole 
in the cap serves for the escape of the air during the succeeding 
process. 

Different kinds of apparatus are used for the expulsion of the 
air by heating the cans. In large factories a steam retort is used 
which resembles in shape a ship's steam boiler. It is provided 
with a door closing air-tight, and is divided in the centre so that 
it can be filled either half or entirely with steam, as may be 
required. The cans to the number of from 400 to 600 are placed 
upon trucks which run upon rails leading into the retort. Eight 
such trucks can be introduced at one time, so that it is possible to 
steam from 30,000 to 40,000 cans per day. The retort being filled 
the door is closed and the pipe communicating with the steam 
boiler opened. The cans remain in the retort from 15 to 30 
minutes, according to the variety of the fruit : berries 1 5 minutes, 
stone-fruits 20, apples and pears 25, quinces and tomatoes 30. 
The door is then opened, and after the steam has some what dispersed 
the trucks are quickly pushed to the tin-shop, where the cap-holes 
are soldered up. To cleanse the cans and make them shiny they 
are next put in a bath of soda water and then rinsed off with 
cold fresh water. They are then transferred to the store room, 
where they remain standing quietly for one week, when they are 
tested by striking the cap of each a short sharp blow with a 
wooden hammer. If everything is in order, the cap sinks slowly 
down, but if it is elastic and jumps back the can is what is called 
a " swellhead," and is returned to the tin-shop for repairs and is 
then again steamed. The perfect cans are labelled and packed 
and are now ready for market. 

Another apparatus which can be highly recommended for small 
factories consists of a round iron plate resting upon a brick basis 



380 VINEGAR, CIDER, AND FRUIT- WINES. 

about one foot high. Two round iron rods run up opposite to 
each other from the edge of this plate and serve as a support for a 
movable iron cylinder open at the bottom and closed on top. 
Upon the iron plate the cans are placed in the form of a pyramid, 
and the cylinder is then drawn down and screwed air-tight to the 
plate. A pipe communicating with the steam-boiler enters the 
cylinder, and as soon as the latter is connected with the plate steam 
is admitted. After a certain time, which corresponds with that 
previously given, the steam is shut off, the cylinder pushed up, 
and the cans removed, the further treatment of which is the same 
as given above. 

In many factories the cans are still heated, according to the old 
method, in boiling water. For this purpose the cans 100 at a 
time are placed upon an iron plate attached to a steam-crane and 
submerged for 15 to 20 minutes in boiling water in a large shal- 
low kettle. In this case the caps are not perforated, but soldered 
down air-tight. A workman watches the cans while they remain 
in the water and by means of a tool removes those from which 
small bubbles arise ; such cans being not air-tight are returned to 
the tin-shop for repairs. The rest after being heated are also 
brought to the tinshop, where the caps are perforated with a hole 
the size of a small pea, which is again soldered up after the escape 
of the heated air. 

The canning of tomatoes, asparagus, and other vegetables is 
effected in a similar manner except that no syrup is used. For 
the following description of tomato canning, which may serve as 
a type for all the rest, we are indebted to Mr. Richard T. Starr, 
of Salem, N. J. 

The tomato was for many years found only in hot-houses and 
conservatories of the rich. It was known as the love-apple and 
considered a curiosity. Our ancestors had no idea that this small 
red berry, for such was about its size, would ever, even under 
careful cultivation, become of mammoth size and form one of 
our most important articles of food. But such is actually the 
case to-day. The exact time when the now great industry of can- 
ning this vegetable commenced cannot be established with any 
certainty. The taste for it seems to be an acquired one, and for 
years the industry struggled in its infancy until the breaking 



PRESERVATION OF FRUIT. 381 

out of the War of the Rebellion caused a demand that rapidly 
grew into gigantic proportions, and to-day finds the tomato-canning 
industry employing an army of men, women, and children, while 
millions of dollars are invested in the payment of labor and the 
erection of plants. 

In order that our readers may have a clear idea of the business 
we will commence with the beginning. Having made up his mind 
to engage in the business on an average scale, the packer will 
first find a suitable plot of ground, on a navigable stream, if pos- 
sible. Having secured this, the next thing is the erection of the 
buildings ; these are generally one story in height and as large and 
roomy as the capital will warrant. The next step is to secure the 
requisite supply of fruit, and for this purpose the farmers are 
drawn on and contracts entered into with them in which the 
packer agrees to take the entire marketable product of a certain 
number of acres or else to take so many tons. These contracts 
are generally made about the first of the year, and as soon as the 
sun drives the frost from the ground the farmer prepares his beds 
and sows his seed. While the latter is growing the land which 
is to be planted is heavily manured and plowed and carefully 
worked until it becomes mellow, and then hills about four feet 
apart are made, and into each one is put a small quantity of com- 
post or phosphates. The tomato plants, having by this time 
grown to the height of 6 or 8 inches, are taken from the beds, and 
on a cloudy day or the latter part of a bright day transplanted 
and tended about as other growing crops. With a favorable sea- 
son the farmer should commence delivering to the factory about 
the middle of August. 

The arrangement of a canning factory is, of course, a matter 
of taste, but the most complete, in our opinion, is one where every- 
thing moves in a straight line, and in which none of the help is 
obliged to interfere with one another. The first thing to be done 
with a load of tomatoes is, of course, to weigh them, and for this 
purpose platform scales are built at an end door and the wagons 
driven on them. After being weighed the tomatoes are handed 
over to the scalder. Tomatoes arriving in all kinds of weather 
and conditions must, of course, not only be washed but scalded, 
so as to thoroughly loosen the skin from the pulp, and to do this 



382 VINEGAR, CIDER, AND FRUIT-WINES. 

quickly and properly, a heavy box of white pine is fitted with 
both steam and water pipes and attached to it is an iron cradle 
swinging on hinges and raised and lowered by a wheel and pulley 
suspended above. On the back of this is placed a box, and as the 
farmer hands off his baskets they are emptied into this box, and 
at the command of the man at the rope, who is called the 
" scalder/' they are dumped into the boiling water beneath. A 
few seconds suffice to clean and scald them ; the cradle is then 
raised and the tomatoes are poured into kettles set in front of the 
scalder to receive them. 

While this has been going on a group of women and girls have 
been filing into the factory and seating themselves along the trays 
that are to receive the tomatoes from the scalder. These trays are 
of different construction, but are similar as regards length, breadth,- 
and depth, the only difference being in the various ways of get- 
ting rid of the water and juice. This is generally done by mak- 
ing a slat frame fit in the bottom and over a trough fastened under 
the tray. This leads to a drain, which carries it to the creek or 
wherever else it is to go. At each tray are from ten to twelve 
women, each of them furnished by the packer with a bowl and 
knife, and provided at their own expense with a neat water-proof 
apron. The tomatoes are dumped from the kettles in front of 
them, and they remove rapidly the already loosened skins and 
cores and deposit the prepared fruit in a bucket sitting beside 
them. They become so efficient that a smart active woman will 
frequently skin from 40 to 60 buckets a day, and as they receive 
4 cents per bucket it Avill be seen they make fair wages. Standing 
just beyond the women are the machines which fill the cans. To 
describe them would be impossible, there being so many shapes 
and many makes. Some are very good, some very poor, every 
man thinks his the best, and so it goes, but in one respect they all 
agree : they have a hopper into which the fruit is poured from the 
buckets, and all have the plunger which forces the fruit into the 
cans ; the treadles of some of them are moved by hand and some 
by steam. The machines rapidly fill can after can, which are then 
set on the " filling table" and receive " top them off/ 7 or in other 
words the fruit is cleared away from the top of the can so that the 
solder used in capping them will not become chilled. They are 



PRESERVATION OF FRUIT. 383 

then placed in trays each holding either 10 or 12 cans and re- 
moved to the " wiping table," where everything is cleared from 
the top, wiped dry with sponges, and the cap placed over the 
opening. The " cappers" stand directly in front of the wiping 
table, and each one has his own fire pot, irons, files, and everything 
he uses before him. Taking the tray, he rapidly applies by means 
of a small brush the acid or flux necessary to make the solder 
flow freely around the cap, and then with the iron melts the solder 
and puts it in the groove. The can is then vented and is ready 
for the " bath." The baths except in size are constructed simi- 
larly to the scalder and a thin cedar cover fits over each one. The 
cans are placed in wire or iron crates, lowered into the boiling 
water, and allowed to remain as long as necessary to cook them. 
The time of working varies in the different factories, but all the 
way from 30 to 50 minutes is required. They are then taken 
from the bath and placed on a slat-floor, where the air can pass 
through them, and when they are cold are "tested" generally by 
striking them with an awl. The testers become so expert that 
they can instantly detect by the sound an imperfect or leaking 
can ; these are thrown out, mended, re-pressed, and put back in 
the pile. The cans are now ready for the next thing, which is 
labelling. 

Labelling is done in different ways, and some canuers with an 
idea of saving labor employ devices which are not only hard on 
the young girls who do the work, but which often result in much 
confusion and poor work. The best method is to divide the help 
into parties of five, one girl sitting on one side of the table with 
paste-pan, brush, and labels and the other four opposite her. 
The one girl, if quick and active, will paste the ends of the labels 
as fast as the other four can put them on the cans. The table is 
of course alongside the pile of cans, and two smart boys will 
place the cans on the table. As a girl labels a can she pushes it 
from her, when it is taken by the boxer, put in the box, and 
nailed up. This mode is simple and effective, and as the gang 
will label from 700 to 900 cases in a day the work progresses 
rapidly. 

In many of the larger factories patent processing kettles, cap- 
ping irons, and improved machinery are used, but as the result 



384 VINEGAR, CIDER, AND FRUIT-WINES. 

is, of course, the same, and they do not affect the mode of pack- 
ing, it is not thought necessary to enter into any description of 
them. 

In the foregoing an outline of the packing process has been 
given, but nothing has been said of the many trials and vexa- 
tions of a canner's life. If everything went always smoothly, it 
would be as pleasant as any other business, but it does not. The 
canner will early in the season employ his hands and commence 
in a small way. He may start and run only two or three hours, 
and for that length of time boilers will have to be fired up, help 
got together, and at the close the factory cleansed the same as if 
he had run the day out. Then, as the crop rapidly matures, work 
becomes heavier, and at last the inevitable " glut" commences, 
and he finds the products of 400 or 500 acres of perishable fruit 
at his doors, may be 50 wagons, each owned by an impatient 
farmer standing in the street waiting his turn to unload. That 
is the time he has need of nerve ; help must be secured, every- 
thing and everybody pushed to their utmost endurance, and from 
early morning until way into the night, day after day, the work 
goes on, help succumbs, and machinery breaks, but the factory 
must move in storm and in sunshine. The work must go on, and 
at last the agony is over, and the crop coming in again gradually 
gives a little relief to the overworked people. And now the crop 
is in, the farmer has brought his "good-bye" load, the force 
places everything in winter-quarters, and with farewells and 
thoughts of the future they separate for their homes and the 
season in a tomato-canning factory is over. 

The taste for tomatoes being, as previously mentioned, an ac- 
quired one, and the people of European countries being slow to 
take hold of them, the principal market the canner has is in this 
country and the demands made by sea-going vessels. The min- 
ing regions of Pennsylvania and of other States use large quan- 
tities, and they have now become a necessity in many households, 
some of the working classes using them largely in place of meat. 
That they are a nutritious, healthy article of food has been 
clearly proved, and the low prices of the past few years have 
placed them within the reach of all. It would be an impossi- 
bility to correctly state the amount of capital invested or the 



PRESERVATION OF FRUIT. 385 

number of persons employed in the industry. The States of 
New Jersey, Maryland, and Delaware pack a large proportion of 
the goods, the late falls and the nature *6f the soil being particu- 
larly well adapted for raising tomatoes, and in every little village 
in these States factories have sprung up like mushrooms within 
the past few years. The business has been brought to a solid 
basis, and with careful handling and the opening of a prosperous 
business future it seems as if it ought to become one of the sub- 
stantial enterprises of this country. 

In connection with the canning of tomatoes it may be of 
interest to our readers to give the preparation of 

Catchups. 

Under the name of catchup or catsup a thickly-fluid sauce 
comes into commerce, which is used as a condiment with meat 
and the fabrication of which has become of some importance. 
Everywhere where Anglo-Saxons reside catchup is found, though 
it has also been introduced on the continent of Europe and in the 
tropics. The varieties most liked are tomato and walnut catch- 
ups, and immense quantities of them are manufactured in the 
American canning establishments. The mode of preparation is 
so simple that it can be introduced into every kitchen. 

Tomato catchup. The receipts for making this favorite catchup 
are innumerable, and should we take those of every packer and 
housewife in the land and put them together they would make a 
good-sized volume. We must therefore limit ourselves to giving 
a few approved receipts. 

Some factories will accumulate the skins and refuse of a 
tomato -canning season, storing the same in vaults and vats until 
the season is over, then cook the mass up and trust to a liberal 
supply of oils and condiments to impose it on an unsuspecting 
public as " fresh tomato catchup," but it is not fresh and should 
not be called so. The proper way to make a good sweet article is 
to place each day in vats or hogsheads the skins, etc., of the day. 
These will by the next morning have become slightly fermented, 
and the skin and pulp can be readily separated by rubbing them 
either with a steam rubber or by hand in a fine copper sieve. In 

25 



386 VINEGAR, CIDER, AND FRUIT- WINES. 

this marmer all seeds, etc. are removed, and the pure, sweet juice 
of the tomato alone remains. Take this, and, having your 
kettles perfectly clean, place it in them and bring it sloicly to 
a boil, carefully skimming off the scum that will rise to the 
top. When it has cooked down about one-half put in your 
cloves and allspice, which should be in bags, and let them remain 
boiling with the rest. Shortly afterwards put in your other 
spices, salt, pepper, etc. ; a small dash of ground cinnamon will 
add much to the flavor, although the person making it must be 
guided by his taste. From a third to half as much vinegar as 
(there is juice should be put in when it is about half cooked, and 
tthe mustard must be thoroughly mixed with vinegar before being 
rput in. Let all now boil until it gets thoroughly done, and if too 
thick, thin it while hot with vinegar and bottle or barrel as 
desired. There can be no receipt given that will suit all 
in regard to the amount of the different condiments to be used, 
as each person has ideas of his own, but all catchup should be 
'made liotter than desired, as it will undoubtedly lose some of its 
strength when it becomes cold. The best of spices and vinegar 
sliould always be used, and every vessel into which it is put 
should be perfectly clean and free from any mold or dust. Seal 
the bottles carefully, and if you have them thoroughly air-tight 
it will like wine improve with age. 

The following receipts can be recommended : 

I. 'Take 15 quarts of thoroughly ripe tomatoes, 4 tablespoon- 
fuls each of black pepper, salt, and allspice, 8 red peppers, and 3 
'teaspoonfuls of mustard. The pepper and allspice must be ground 
fine and the whole boiled slowly 3 to 4 hours; then pass all 
through .-a fine sieve and when cold put it in bottles, which must 
be immediately sealed. 

II. Boil 4 quarts of tomatoes together with 2 quarts of vine- 
gar, 2 tablespoonfuls of red pepper, 4 tablespoon fuls of black 
pepper, 1 tablespoonful of cloves, 1 teaspoonful of salt, and 1 
ground nutmeg to a thick paste. Strain through a coarse-meshed 
ieve and sweeten the sauce obtained with J Ib. of sugar. Fill 
in bottles and shake once every day for a week. 

III. Cut up perfectly ripe tomatoes and place them upon the 
fire until they commence to bubble. Then take them from the 



PRESERVATION OF FRUIT. 387 

fire, and when cool rub them with the hand through a hair-sieve 
and season according to the following proportions: For each 
quart of sauce add 1 teaspoonful of ground allspice, 1 teaspoonful 
of ground cloves, 1 tablespoonful of salt, and 1 quart of wine- 
vinegar. Stir the whole thoroughly together, replace it upon the 
fire, and boil for one hour, with constant stirring. When cool 
put the catchup in bottles and seal immediately. 

Walnut catchup. I. In June, when the walnuts are still soft, 
take 10 dozen of them, and after crushing pour over them 2 
quarts of wine-vinegar, add the following spices, all ground : 2 
tablespoonfuls of black pepper, 1J oz. of nutmeg, 40 cloves, J oz. 
of ginger, and J oz. of mace, and boil the whole J hour, stirring 
constantly. When cold strain through a hair-sieve and put the 
catchup in bottles. 

II. Crush about 10 dozen of young, soft walnuts, sprinkle 
f Ib. of salt over them, and then add 1 quart of vinegar. Let 
the whole stand six weeks, stirring frequently. Then strain 
through a bag, with constant pressing with the hand. Pour 1 
pint of vinegar over the residue, let it stand over night, and 
strain again through the bag. Combine the fluid with that pre- 
viously obtained and season with the following spices, all ground : 
1J oz. of black pepper, J oz. of nutmeg, J oz. of ginger, J oz. of 
mace, and 40 cloves. Then boil J hour, strain through a hair- 
sieve, and bottle. 

Cucumber catchup. Thoroughly ripe cucumbers, before turning 
yellow, are peeled and grated upon a coarse grater. This paste is 
brought into a colander to allow the juice to run off, then pressed 
through a coarse hair-sieve to remove the seeds, and finally brought 
into small, wide-mouthed bottles, which are filled f full. The re- 
maining space is filled up with good wine-vinegar. This catchup 
has the taste and odor of fresh cucumber, and is used as a condi- 
ment with meat. Before bringing it to the table it is seasoned 
to taste with salt and pepper. 

Horseradish catchup. The mode of preparation is the same as 
for the preceding, putting the grated mass in a colander and 
straining through a hair-sieve being, however, not necessary. 
Both varieties of catchup must be immediately corked, sealed, 
and kept in a cool place. Within the last few years both have 



388 VINEGAR, CIDER, AND FRUIT-WINES. 

been prepared on a large scale in the United States and in Eng- 
land, and have become an article of export. They are packed in 
small, wide-mouthed bottles, sealed, and provided with gayly- 
colored labels. Some English factories use small earthenware 
pots of a cream color, closed with corks over which is tied strong 
colored paper. The pots are very good, but the manner of 
closing them is not ; the corks should be sealed. 

Currant catchup. Heat nearly to the boiling point, with con- 
stant stirring, 4 Ibs. of thoroughly ripe currants together with 1 J 
Ib. of sugar. Then add 1 tablespoonful each of cinnamon, salt, 
cloves, and pepper all finely pulverized and 1 quart of vine- 
gar. Boil the mixture one hour and then treat in the same man- 
ner as tomato catchup. 

Gooseberry catchup. This product also comes into commerce 
under the name of "spiced gooseberries;" it is an excellent con- 
diment with roast fowl. Take 6 quarts of gooseberries, ripe or 
unripe as may be desired, and carefully remove the stems and 
pistils. Then bring them into a kettle, and after pouring some 
water and scattering 5 Ibs. of pulverized sugar over them, boil 
for 1J hour. After boiling for 1J hour add 4 Ibs. more of 
sugar and 1 tablespoonful each of allspice, cloves, and cinnamon. 
The catchup is not strained, but brought at once and while warm 
into wide-mouthed bottles or pots, which are immediately corked 
and sealed. It is advisable, before closing the bottles, to lay a 
closely-fitting piece of salicylated paper upon the surface of the 
catchup. The bottles should be kept in a cool place. 

It is scarcely necessary to remark that catchup can be prepared 
not only from the above, but from all varieties of fruit, as it is 
only necessary to take one of the above receipts as a type. But, 
with few exceptions, those given are the only catchups prepared 
on a large scale and brought into commerce. 

Another subject which may be referred to in connection with 
the preservation of fruit is the preparation of 

Fruit-butter , Marmalade, and Jelly. 

Fruit-butter. The manufacture of apple-butter, which may 
serve as a type of that of all other fruit-butters, is effected as 



PRESERVATION OF FRUIT. 389 

follows : Fill the boiler two-thirds full with the juice of sweet 
and bitter-sweet apples in about the same proportion as given 
for the manufacture of cider. The other third of the boiler is 
filled up with slices of ripe, juicy apples, and the mixture boiled, 
with frequent stirring. When the slices of apples are so soft that 
they commence to fall to pieces, they are carefully removed from 
the boiler by means of a skimmer, care being had to allow the 
juice to run oif. The same quantity of fresh slices of apples is 
then brought into the juice and boiled in the same manner as the 
preceding. When these have acquired the necessary degree of 
softness, the entire contents of the kettle, together with the slices 
of apples previously boiled, are brought into a stoneware pot and 
allowed to stand covered for 12 hours. The mass is then re- 
placed upon the fire and boiled, with constant stirring, until it 
has acquired the consistency of soft soap. If desired, it can at 
the same time be seasoned with cinnamon, nutmeg, etc. To pre- 
vent scorching the second boiling is effected in vessels standing 
in boiling water. 

In the same manner fruit-butter can be prepared from all 
varieties of fruit, pear or apple juice forming, however, always 
the boiling liquor. Apple and peach butters are commercially of 
the greatest importance, though butter of quinces, pears, black- 
berries, cherries, plums, and cranberries is also manufactured on 
a large scale. Whortleberries, which grow in enormous quantities 
in some parts of the country, might also form an excellent material 
for this product. In the foregoing only the varieties are mentioned 
which are manufactured on a large scale by American and English 
factories that chiefly control the trade in fruit-butters, but these do 
not by any means exhaust the list ; green gages can, for instance, 
be highly recommended for the purpose. 

The excellent product brought from France into commerce 
under the name of raisine is prepared in the above manner by 
slowly boiling sliced apples and pears in unfermented grape-juice. 

Fruit-butter is packed in wooden buckets of 5 or 10 Ibs. capa- 
city. Tin cans holding 2 Ibs. jire also sometimes used, but they are 
not liked. The buckets are slightly conical towards the top and 
are provided with a wire handle. Resinous wood should not be 
used in their construction, as it would impart an odor to the fruit- 



390 VINEGAR, CIDER, AND FRUIT-WINES. 

butter. The buckets are filled up to the edge, and a closely fitting 
round piece of paper previously saturated with concentrated 
solution of salicylic acid in whiskey is laid on top of the butter. 
The tight-fitting lid is placed upon the bucket without being 
sealed or otherwise closed. A large label occupying the space 
between the lower and upper hoops finishes the packing. 

Marmalade. The same product is sometimes called marmalade 
and sometimes jam. The French prepare only marmalade, while 
the Englishman brings the same product into commerce as jam 
or as marmalade, just as it may suit him best, and the German is 
not much better. The manufacturers, to be sure, would some- 
times like the public to believe that marmalade is a finer product 
containing more sugar and spices than jam, but such is not the 
case, because the raw material and the mode of preparation are 
the same. The term marmalade was originally applied to a jam 
prepared from quinces, it being derived from marmdo, the Portu- 
guese word for quince. The term was gradually given to all 
jams in order to give them a more distinguished character, and this 
has led to a confusion of terms which sometimes extends even to 
jelly. There is, however, a wide distinction : marmalade or jam 
is prepared from the pulp of fruit and jelly from the juice, while 
fruit-butter, as above indicated, is a blending of both with the 
omission of sugar. 

For the manufacture of marmalade on a large scale all the rules 
and receipts can be condensed as follows : The fruit must be of 
excellent quality, entirely free from blemishes and washed per- 
fectly clean. Kernel fruit is peeled, quartered, and freed from the 
cores ; peaches are also peeled, halved, and stoned ; other stone- 
fruit is only stoned and halved, while berries are carefully freed 
from the stems. Melons and pumpkins are peeled and cut into 
small pieces. Rhubarb should not be washed but rubbed with a 
moist cloth and be then cut into small pieces. Tomatoes are to be 
peeled, which is facilitated by previously placing them for one 
minute in hot water. Being thus prepared the fruit is brought 
into a copper kettle and as much water as is required for boiling 
added. While the fruit is boiling, weigh off as many pounds of 
white sugar as there is fruit, soak it in water, boil and skim care- 
fully. The fruit should be boiled quickly, and when perfectly 



PKESERVATION OF FRUIT. 391 

oft is allowed to cool off somewhat and then rubbed through a 
wide-meshed hair-sieve. The mass passing through the sieve is 
combined with the sugar and replaced upon the fire. The whole 
is then boiled, with constant stirring, to the required consistency. 
The latter is tested by taking a small sample with a wooden or 
bone spoon nothing else should be used and if it draws threads 
between the fingers the boiler is removed from the fire. The 
marmalade is then brought into straight jars, and after laying a 
piece of salicylated paper on top, the jars are tied up with white 
parchment paper or sometimes covered with a glass cover and 
labelled. It may be remarked that in the last stage of boiling 
the marmalade is sometimes flavored, which is generally effected 
by stirring in lemon juice, cinnamon, and nutmeg according to 
taste. The liquor obtained by boiling crushed kernels of plums 
or peaches is also frequently at the same time added as flavoring. 
Frequently the sugar is not treated as stated above, but added in 
the form of powder. 

The quantity of sugar has above been given in the proportion 
of 1 Ib. to 1 Ib. of fruit. Though this is the customary rule, many 
manufacturers use only J Ib. of sugar, a method which can be 
highly recommended. In fact there is frequently a perfect waste 
as regards the addition of sugar, some adding even 1J Ib. of it to 
the pound, whereby the taste of fruit is entirely lost and the pro- 
duct, on account of its sweetness, becomes repugnant to many. 
It may be laid down as a rule that in all fruit boiling no more 
sugar than is absolutely necessary should be used. The secret of 
the great reputation the products of the principal American fac- 
tories enjoy in all portions of the world is simply due to the fact 
that they use as little sugar as possible, whereby the products are 
rendered not only cheaper but they retain their natural fruit taste, 
and that is what the consumer desires and not a sugary paste 
having only the color of the preserved fruit. The durability of 
the product need not necessarily suffer if due care is exercised in 
its preparation. Marmalade should not be made, as it is only too 
frequently done, from fruit which has been gathered for several 
days and shows signs of decay. Fruit not over-ripe and freshly 
gathered should be used and the boiling finished as quickly as 
possible. By then rinsing the jars with salicylated water and 



392 VINEGAR, CIDER, AND FRUIT-WINES. 

covering the marmalade with a piece of paper saturated with con- 
centrated solution of salicylic acid or with alcohol, } Ib. of sugar 
to 1 Ib. of fruit will be ample, and even J ib. with sweet fruits 
such as pears, raspberries, etc. Independently of the saving of 
sugar, such marmalade will give better satisfaction than an article 
twice as sweet, and will keep well in a dark cool place. 

From France a very fine perfumed apple marmalade is brought 
into commerce. It is prepared from equal parts of Calvilles and 
Pippins, and after boiling is sprinkled with rose-water or violet 
essence. 

The term tutti-frutti is applied to marmalade prepared from a 
mixture of different kinds of fruit. As the name implies it is 
of Italian origin. The composition is made according to taste 
and the fruits at disposal. 

Jelly. This product is, unfortunately, often made expensive 
and at the same time spoiled by too large an addition of sugar. 
Many housekeepers do not like to prepare jellies under the pre- 
text that it requires too much sugar; but this is an error, because 
in France, in factories as well as in households, they use only J 
pound, or at the utmost f pound, of sugar to the pound of fruit, 
instead of 1 pound or even 1 J pound, as is customary in Eng- 
land, Germany, and parts of the United States. Moreover, the 
apple-jelly which is made in the United States and sent to all 
parts of the world is made without any addition of sugar. In- 
stead of apples, as the raw material, apple-juice is used, which 
must be perfectly sweet and treated immediately after it comes 
from the press. A moderate temperature is absolutely necessary 
for success, for, if the juice commences to ferment and it does 
very rapidly in warm weather the keeping quality of the jelly 
is injured, except it be mixed with a considerable quantity of 
sugar. A temperature of 41 F. is considered the most suitable, 
and if it rises to above 66 F. the manufacture is at once stopped. 
The juice runs directly from the press into the boiler, under 
which a strong fire is kept because the starchy matters contained 
in the juice are only converted into sugar if the boiling down is 
quickly effected. For this reason shallow pans offering a large 
surface to the fire are used. When the juice commences to boil 
it is clarified, and the acid it contains neutralized by the addition 



PRESERVATION OF FRUIT. 393 

of one teaspoonful of elutriated chalk to each quart of juice. 
The chalk weighed off in this proportion is mixed with the juice, 
and appears in a few minutes as a thick scum upon the surface 
from which it is carefully removed with a skimmer. By this 
operation the jelly is clarified, and all the albuminous substances 
contained in it being removed by the chalk, filtering is not re- 
quired. The process is similar to the defecation of the juice of 
sugar-cane and beets by lime. The juice is now boiled to the 
consistency of 30 or 32 B., which is found on cooling to be the 
proper point for perfect jelly. It is then filled direct from the 
pan into tumblers, which are treated in the same manner as mar- 
malade jars. 

Successful jelly boiling on a large scale is impossible without 
the use of the saccharometer. It is the only reliable guide for 
the addition of sugar, for if the product is to be protected from 
spoiling it must show from 30 to 32. If this result can be 
reached without the addition of sugar, it is so much the better. 

Pear and mulberry jellies are prepared in exactly the same 
manner as above. Other fruits containing more acid require an 
addition of sugar, especially currants, which next to apples and 
pears are most used for jelly, but in no case is the same weight of 
juice and sugar required. 

To prepare jelly from berries and other small fruit, pour hot 
water over the fruit in order to free it from adhering dirt and to 
facilitate the separation of the juice. When the water is cool 
take the berries out, express the juice, and bring the latter im- 
mediately into a copper or brass kettle over a lively fire. Then 
stir in pulverized sugar, the quantity of which varies according 
to the variety of fruit. For raspberries, strawberries, and black- 
berries J pound of sugar to the pound of juice will be sufficient, 
and pound or at the utmost f pound for currants, barberries, 
elderberries, and whortleberries. The sugar being added stir in 
the chalk in the proportion previously given, and after allowing 
the Juice to boil not longer than 15 minutes, take it from the fire 
and strain it at once into the glasses. In this manner a clear, 
beautiful jelly of an agreeable taste will be obtained. If, on the 
other hand, the juice is boiled slowly over a weak fire, the result 
will be a turbid product which has lost its fruity taste. 



394 VINEGAR, CIDER, AND FRUIT-WINES. 

Stone-fruit is boiled, and after boiling it with a small quantity 
of water until soft the juice is pressed out and f pound of sugar 
added for every pound. It should be boiled quickly, and not, as 
some receipts have, for f hour. Quinces are peeled and then 
treated like stone-fruit. Rhubarb is cut into small pieces and 
then treated in the same manner. A quite good jelly can also be 
prepared from the medlar, provided it is allowed to become com- 
pletely ripe, and is then slowly steamed with a very small quan- 
tity of water. When thoroughly soft the juice is pressed out 
and f pound of sugar added to each quart. The mass is sharply 
boiled for 20 minutes, when the result will be a clear jelly. 

In France, as previously mentioned, perfumed marmalade is 
prepared from equal parts of Calvilles and Pippins. From the 
same material, which is considered best for the purpose, a per- 
fumed jelly is also prepared. The apples are not peeled, but cut 
into slices, and boiled with a small quantity of water until soft 
enough to be pressed in a filter-bag. To every pound of juice 
J pound of sugar is added, and five minutes before the saccharo- 
meter indicates 30 B., J or J pound of violet blossoms is stirred 
into the juice, a few drops of cochineal being generally added to 
improve the color. The jelly, when finished, is strained through 
a hair-sieve into wide-mouthed bottles which are corked and 
sealed. 

A jelly is made from raspberries, and sometimes also from 
strawberries and blackberries, in which the berries remain intact. 
The process consists in dissolving 2 pounds of white sugar in 
water and boiling until thickly fluid. Two pounds of berries are 
then brought into the kettle and carefully mixed with the sugar 
so as to avoid crushing. The kettle is then taken from the fire 
and allowed to stand covered for 15 minutes, when it is replaced 
and the sugar boiled up once more. The product is kept in jars 
well corked and sealed. 

In conclusion we give the process of manufacturing apple-jelly 
in the largest factory in Oswego County, New York, as described 
by Mr. Dewitt C. Peck. There are some features peculiar to this 
establishment which may be new and interesting. 

The factory is located on the Salmon Creek, which affords the 
necessary power. A portion of the main floor, first story, is occu- 



PRESERVATION OF FRUIT. 395 

pied as a saw-mill, the slabs furnishing fuel for the boiler furnace 
connected with the evaporating department. Just above the mill, 
along the bank of the pond and with one end projecting over the 
water, are arranged eight large bins holding from 500 to 1000 
bushels each, into which the apples are delivered from the teams. 
The floor in each of these has a sharp pitch or inclination towards 
the water, and at the lower end is a gate through which the fruit 
is discharged, when wanted, into a large trough half submerged 
in the pond. 

Upon hoisting a gate in the lower end of this trough consider- 
able current is caused, and the water carries the fruit a distance 
of from 30 to 100 feet, and passes into the basement of the mill, 
where, tumbling down a four-foot perpendicular fall into a tank, 
tight , in its lower half and slatted, so as to permit the escape of 
water and impurities, in the upper half, the apples are thoroughly 
cleansed from all earthy or extraneous matter. Such is the fric- 
tion caused by the concussion of the fall, the rolling and rubbing 
of the apples together, and the pouring of the water, that decayed 
sections of the fruit are ground off and the rotten pulp passes 
away with other impurities. From this tank the apples are 
hoisted upon an endless chain elevator, with buckets in the form 
of a rake-head with iron teeth, permitting drainage and escape of 
water, to an upper story of the mill, whence by gravity they de- 
scend to the grater. The press is wholly of iron ; all its motion, 
even to the turning of the screws, being actuated by the water- 
power. 

The cheese is built up with layers inclosed in strong cotton 
cloth, which displaces the straw used in olden times and serves 
also to strain the juice. As it is expressed from the press tank 
the juice passes to a storage tank and thence to the defecator. 
This defecator is a copper pan 11 feet long and about 3 feet wide. 
At each end of this pan is placed a copper tube 3 inches in diam- 
eter and closed at both ends. Lying between and connecting 
these two are twelve tubes also of copper, 1J inch in diameter, 
penetrating the larger tubes at equal distances from their upper 
and under .surfaces ; the smaller being parallel with each other, 
and 1J inch apart. When placed in position the larger tubes, 
which act as manifolds, supplying the smaller with steam, rest 



396 VINEGAR, CIDER, AND FRUIT-WINES. 

upon the bottom of the pan, and thus the smaller pipes have a 
space of } inch underneath their outer surfaces. 

The apple-juice conies from the storage tank in a continuous 
stream about f inch in diameter. Steam is introduced to the 
large or manifold tubes, and from them distributed through the 
smaller ones at a pressure of from 25 to 30 Ibs. per inch. Trap- 
valves are provided for the escape of water formed by condensa- 
tion within the pipes. 

The primary object of the defecator is to remove all impurities 
and perfectly clarify the liquid passing through it. 

All portions of pomace and other minute particles of foreign 
matter, when heated, expand and float in the form of scum upon 
the surface of the juice. An ingeniously contrived floating rake 
drags off this scum and delivers it over the side of the pan. To 
facilitate this removal, one side of the pan, commencing at a point 
just below the surface of the juice, is curved gently outward and 
upward, terminating in a slightly inclined plane, over the edge 
of which the scum is pushed by the rake into a trough and car- 
ried away. 

A secondary purpose served by the defecator is that of reducing 
the juice by evaporation to a partial syrup of the specific gravity 
of about 20 B. When of this consistency the liquid is drawn 
from the bottom and the less agitated portion of the defecator by 
a syphon and thence carried to the evaporator, which is located 
upon the same framework and just below the defecator. 

The evaporator consists of a separate system of six copper tubes, 
each 12 feet long and 3 inches in diameter. These are jacketed, 
or inclosed in an iron pipe of 4 inches internal diameter, fitted 
with steam-tight collars so as to leave half an inch space sur- 
rounding the copper tubes. The latter are open at both ends, 
permitting the admission and egress of the syrup and the escape 
of the steam caused by evaporation therefrom, and are arranged 
upon the frame so as to have a very slight inclination downward 
in the direction of the current, and each nearly underneath its 
predecessor in regular succession. Each is connected by an iron 
supply-pipe, having a steam-gauge or indicator attached, with a 
large manifold, and that by other pipes with a steam boiler of 30 
horse-power capacity. 



PRESERVATION OF FRUIT. 397 

Steam being let on at from 25 to 30 Ibs. pressure, the stream 
of syrup is received from the defecator through a strainer, which 
removes any impurity possibly remaining, into the upper evapo- 
rator tube ; passing in a gentle flow through that, it is delivered 
into a funnel connected with the next tube below, and so back 
and forth through the whole system. The syrup enters the 
evaporator at a consistency of from 20 to 23 B. and emerges 
from the last tube, some three minutes later, at a consistency of 
from 30 to 32 B., which is found on cooling to be the proper 
point for perfect jelly. This point is found to vary one or two 
degrees, according to the fermentation consequent upon bruises in 
handling the fruit, decay of the same, or any little delay in ex- 
pressing the juice from the cheese. The least fermentation occa- 
sions the necessity for a lower reduction. To guard against this, 
no cheese is allowed to stand over night, no pomace left in the 
grater or vat, no juice in the tank; and further to provide against 
fermentation a large water-tank is located upon the roof and filled 
by a force-pump, and by means of hose connected with this, each 
grater, press, vat, tank, pipe, trough, or other article of machinery 
used can be thoroughly washed and cleansed. Hot water instead 
of juice is sometimes sent through the defecator, evaporator, etc., 
until all are thoroughly scalded and purified. 

If the saccharometer shows too great or too little reduction, the 
matter is easily regulated by varying the steam pressure in the 
evaporator by means of a valve in the supply pipe. 

If boiled cider instead of jelly is wanted for making pies, 
sauces, etc., it is drawn off from one of the upper evaporator tubes, 
according to the consistency desired ; or it can be procured at the 
end of the process by simply reducing the steam pressure. 

As the jelly emerges from the evaporator it is transferred to a 
tub holding some 50 gallons, and by mixing a little therein any 
slight variations in reduction or in the sweetness or sourness of 
the fruit used are equalized. From this it is drawn through fau- 
cets, while hot, into the various packages in which it is shipped 
to market. 

A favorite form of package for family use is a nicely turned 
little wooden bucket with cover and bail, of two sizes, holding 5 



398 VINEGAR, CIDER, AND FRUIT-WINES. 

and 10 pounds respectively. The smaller packages are shipped 
in cases for convenience in handling. 

The present product of this factory is from 1500 to 1800 pounds 
of jelly each day of 10 hours. It is calculated that improvements 
now in progress will increase this to something more than a ton 
per day. Each bushel of fruit will produce from 4 to 5 pounds 
of jelly, fruit ripening late in the season being more productive 
than other varieties. Crab-apples produce the finest jelly, sour 
crabbed natural fruit makes the best-looking article, and a mixture 
of all varieties gives most satisfactory results as to flavor and gen- 
eral quality. 

Saving of the apple-seeds. As the pomace is shovelled from the 
finished cheese it is again ground under a toothed cylinder, and 
thence drops into large troughs th rough a succession of which a 
considerable stream of water is flowing. Here it is occasionally 
agitated by raking from the lower to the upper end of the trough, 
as the current carries it downward, and the apple-seeds becoming 
disengaged drop to the bottom into still water while the pulp 
floats away upon the stream. A succession of troughs serves to 
remove nearly all the seeds. 

The value of the apple-seeds thus saved is sufficient to pay the 
daily wages of all the hands employed in the establishment. 

The apples are measured in the wagon-box, one-and-a-half 
cubic feet being accounted a bushel. 

The establishment is owned by George B. Bloomer, of Xew 
York, who is also the inventor of the defecator, evaporator, and 
much of the other machinery in use. It was erected late in the 
season of 1880, and manfactured that year about 45 tons of jelly, 
besides considerable cider exchanged to the farmers for apples, 
and some boiled cider. 

The price paid for apples in 1880, when the crop was super- 
abundant, was 6 to 8 cents per bushel ; in 1881, 15 cents. 

Such institutions are important to the farmer in that they use 
much fruit, not otherwise valuable and very perishable. Fruit so 
crabbed and gnarled as to have no market value, and even frozen 
apples, if delivered while yet solid, can be used. Such apples 
are placed in the water while frozen, the water draws the frost 
sufficiently to allow of their being grated, and passing through 



PRESERVATION OF FRUIT. 



399 



the press and evaporator before there is time for chemical change, 
they are found to make very good jelly. These establishments 
are valuable to the consumer by converting the perishable, cheap, 
almost worthless crop of abundant years into such enduring form 
that its consumption may be carried over to the years of scarcity, 
and furnish healthful food in cheap and pleasant form to many 
who would otherwise be deprived, and lastly they are of great 
interest to society in that they give to the juice of the apple twice 
the value for purposes of food which it has or can have, even to 
the manufacturer, for use as a beverage. 

We will finally devote some space to the description of the 
most important apparatus required in the preservation of fruit, viz : 



The Kettle. 

Without entering into a discussion of the various kettles used 
in other countries, we give in Fig. 75 an illustration of a very 
practical apparatus much used in American preserving establish- 
ments. A few words will suffice for explanation. A, B, C iudi- 

Fig. 75. 




cate a washing apparatus for washing the fruit, and which can be 
lifted out. When this is done a lid similar to D is hung near the 
chimney. The basket or crate E, as here shown, is of wire, in 
which form it serves for fruit to be dipped into hot water for a 
few moments only, as, for instance, peaches which are to be pared. 



400 VINEGAR, CIDER, AND FRUIT-WINES. 

For boiling down in a water bath a copper basket is used. The 
fire-place is of double sheet iron, the doors and grate of cast-iron. 
The kettle is of copper and jacketed on the four sides with two 
inch boards. In the centre it is divided by a movable copper 
partition. It is 10 inches deep, 48 inches wide, and 60 inches 
long. The entire apparatus weighs 1 50 pounds. It is, of course, 
scarcely necessary to mention that this kettle is manufactured in 
all sizes according to the requirements of the manufacturer. As 
seen in the illustration, the fire-place extends beneath the entire 
width and length of the kettle whereby the contents are quickly 
heated with a comparatively small consumption of fuel. The 
apparatus being transportable it can be placed wherever most 
convenient, and being accessible from all sides its use is very con- 
venient and saves time. 



CHAPTER XXX. 

EVAPORATION OF FRUIT. 

OF all the methods employed for preserving fruit for any length 
of time none has a greater future before it than the one to be dis- 
cussed in this chapter. The reason for this can be readily given : 
the process does not require great technical skill; it excels in 
cheapness because neither vessels, sugar, nor other auxiliaries are 
required, the product possesses excellent keeping qualities, retains 
its natural flavor, and being healthier and more agreeable than 
fruit preserved by any other method, is especially suitable for food 
for the masses. 

Evaporated fruit of to-day is entirely different from the dried 
fruit of a dozen years ago. Who does not remember the shrivelled, 
dark-colored, wedge-shaped pieces of apple and peach that were 
sold by the family grocer ? They possessed the tenacity of sole- 
leather and were uninviting to look and smell. Before they could 
be used in the home-made pies they required to be boiled and 
stewed for hours at a time. The preparation of dried fruits of 
those days was primitive. Farmers' wives and daughters pared 



EVAPORATION OF FRUIT. 401 

and sliced the apples by hand and placed them on wooden trays, 
which were set out in the sun. It took days to dry the fruit, 
and exposure to showers and the night air had to be avoided or 
the lot would be spoiled. The advent of steam evaporators and 
scientific methods has wrought a great change in the business. 
Large evaporating establishments have been put up, thousands of 
men given employment, and a prosperous industry created. The 
superiority of the evaporated fruits to the sun-dried article has 
caused an immense demand for them, and aside from the con- 
sumption in this country large amounts are shipped abroad. The 
new processes now in use produce fruit that retains much of its 
original color, and that is as palatable as though it were in its fresh 
and natural condition. 

The following statement may suffice to show to what proportions 
the business has grown: Within a radius of 40 miles of Roches- 
ter, New York, there are 1 500 evaporators, from the small farm- 
house apparatus, with a capacity of 25 bushels per day, to the 
large steam evaporators drying from 800 to 1000 bushels of apples 
every 24 hours. These evaporators employ over 30,000 hands 
during the fall and early winter months. Large quantities of 
apples of a quality that was formerly wasted are utilized, and the 
profits of fruit raising largely increased. The annual product 
of evaporated fruit in the State of New York alone is now esti- 
mated at 30,000,000 pounds worth at first cost about $2,000,000. 
In order to produce this quantity of dried fruit no less than 
5,000,000 bushels of apples are required and 15,000 tons of coal 
consumed. A constant attendance, night and day, of an army of 
men, women, and children, numbering 30,000, is necessary. The 
process of evaporation eliminates 225,000 tons of water, reducing 
the green fruit to about one-eighth of its original weight, each 
100 Ibs. yielding when properly evaporated 12 Ibs. of fruit. 

Aside from the fact that evaporated fruit can be transported to 
any clime without deterioration, the advantage in the cost of 
freight is great. A case of concentrated product costs 30 cents for 
transportation to Liverpool ; in the green state the 8J bushels 
required to produce the 50 Ibs. contained in each case, would cost 
$2.25, and in the canned state the cost would be $2.10. The 
total exports of evaporated and dried apples for the fiscal year 

26 



THF. 



402 VINEGAR, CIDER, AND FRUIT-WINES. 

ending June 30, 1888, were 1,803,161 Ibs., of the value of 
$812,682. Some idea may be gathered of the enormous increase 
of the fruit-growing industry from the fact that in 1850 the fruit 
crop of the United States was valued only at $8,000,000, while 
in 1886 it was estimated at $137,000,000. 

The process of evaporating fruit is a comparatively recent one, 
it being not more than fifteen years since the granting of the Aldeu 
patent. Like all other new inventions some years were required 
before its merits became thoroughly understood, though at the 
Paris Exhibition of 1878 the first prize was unanimously awarded 
to the fruit dried by that process. Since then it has spread from 
California, where it was first introduced, throughout the entire 
country, and has created a complete revolution in the fruit industry. 
A number of other apparatuses have been invented, but they are 
all based upon the same principle. At first only kernel and stone- 
fruits were evaporated, but at the present time the list comprises 
the following articles : apples, pears, peaches, apricots, plums, 
nectarines, figs, cherries, blackberries, grapes, green corn, peas, 
potatoes, sweet potatoes, onions, tomatoes, pumpkins, rhubarb, 
asparagus, hops, tobacco, meat, oysters, fish, and eggs. This list 
is not by any means complete, because what has been said of the 
canning industry also holds good as regards the evaporating 
establishments : they every year include within the sphere of their 
activity new suitable articles. And it is no wonder, because their 
products bring double the price of those dried in the sun or in the 
oven. A great advantage of evaporated fruit is that it, even after 
years, regains its natural form and freshness when placed a few 
hours in fresh water and then boiled up with an abundant addition 
of water. No leathery skin nor unnatural taste of sugar is ob- 
served. To all who desire the natural taste of the fruit there can 
be no question that evaporated fruit is preferable to that preserved 
with sugar in cans, which at the present time is its principal com- 
petitor. And this result is obtained by less expensive means and 
with greater certainty. The tin cans cost sometimes four times 
as much as the fruit they contain, and the loss by leakage amounts 
on an average to 10 per cent., though occasionally to the entire 
value of the shipment. Complaints have been made by nearly 
every expedition to the North Pole that a considerable portion of 
their canned goods had to be thrown overboard, making retrench- 



EVAPORATION OF FRUIT. 403 

ment necessary, which sometimes amounted to actual want. When, 
in 1881, the steamer " Rodgers" was ready to sail from San Fran- 
cisco in search of the " Jeanette" it was detained for eight days by 
the discovery that of the stock of canned goods on board 4000 
cans were leaky, and contained provisions already in a state of 
decay. Every sea-captain can tell of the same kind of experience. 
The blame rests partially upon the manufacturers who permit the 
work to be done carelessly, and do not take into consideration that 
the slighest access of air spoils the contents of the can, but par- 
tially also upon the mode of preservation itself, because even 
faultlessly closed cans have the disadvantage that when once 
opened their contents must be immediately used, while the packages 
containing evaporated fruit may remain open for years in every 
climate. Moreover, in eating the latter, lead poisoning need not 
be feared, and, as previously stated, it has the further advantage 
of a great reduction in the cost of freight. Green peas, of which, 
as is well known, immense quantities are canned, may serve as 
another example. In the canned state seven boxes of them weigh 
350 Ibs., while one box of evaporated peas, which contains the 
same quantity of substance, but deprived of its content of water, 
weighs only 43 Ibs., though when placed upon the table there is 
not the slighest difference as regards quality between the two 
articles. Taking into account all these advantages, and considering 
at the same time that by a good method of drying the hazards 
and annoyances connected with the preservation of fruit in a fresh 
state can be largely overcome, it must be concluded that the 
evaporating process is destined to play in the future a still greater 
part in the preservation of fruit than it does already at the 
present time. 

Before entering upon a description of the apparatus and its use, 
it will be necessary to explain the principle upon which it is based 
and the theory of evaporating fruit. 

The object to be attained is not only to make the fruit keep, 
but also to retain the properties for which it is valued. This can 
only be reached by withdrawing the content of water, and at the 
same time converting a portion of the starch into sugar in as short 
a time as possible without boiling the fruit. The latter would 
injure the taste of the fruit, and slow drying gives a flavor calling 
to mind decay. The quicker the watery portions are removed 



404 VINEGAR, CIDER, AND FRUIT-WINES. 

from thoroughly ripe fruit the richer and more durable its taste 
will be; and the more completely the oxygen of the air is ex- 
cluded during this process the more perfectly will it retain its 
color. Rapidity of the drying process sometimes increases the 
content of sugar by 25 per cent., and this increase is in an exact 
proportion to a slower or quicker evaporation of the content of 
water, always provided, however, the fruit does not suffer injury 
from the heat. 

Any one who has boiled down the juice of the maple, sorghum, 
sugar-cane, or sugar-beet knows that with slow evaporation sugar is 
not formed, the content of sugar being then converted into acid. 
Now, the change of substance must be constantly kept in view : 
starch is converted into sugar (in this case very largely already in 
the plant), sugar into alcohol, and alcohol into vinegar. This ex- 
perience must also hold good in drying fruit. The chemical pro- 
cess by which the content of starch of the fruit, when brought into 
a high temperature, is converted into sugar is similar to that during 
the ripening process on the tree, only it takes place more rapidly. 

A few days of warm sunshine produce sufficient sugar in goose- 
berries and grapes to change the sour unpalatable fruits to a re- 
freshing article of food. A few hours in an evaporating appa- 
ratus, in which the proper degree of heat is maintained, can produce 
a still greater change, provided the fruit be not placed in it before 
it has reached perfection in a natural manner. It must be re- 
membered that 212 F. is the boiling point, and that subsequent 
treatment, no matter how careful, cannot restore the taste lost in 
such a temperature. Of no.less importance is another point : the 
surface of the fruit to be dried must be kept moist and soft, so 
that the internal moisture may find a way by which it can readily 
and quickly escape, and a strong hot current of air must uninter- 
ruptedly pass over the fruit to carry off the escaping moisture. 
Hence, cold air must under no circumstances have access to drying 
fruit, and above the latter an aperture must be provided for the 
escape of the air saturated with moisture. 

The apprehension that fruit cannot be dried in a hot moist ap- 
paratus is refuted by the well-known scientific fact, that air of the 
temperature of the freezing point absorbs T J V part of its weight 
of moisture, and that its capacity for absorption doubles with 
every 15 C. (59 F.) of higher temperature. Thus, if the tern- 



EVAPORATION OF FRUIT. 405 

perature is 59 F. it absorbs J^ part of its weight of water, 86 
F. J-o P art , 113 F - TO Part, 140 F. ^ part, 167 F. J part, 
194 F. f part, and 221 F. its own weight, which is nearly 
equal to one pound of w r ater to every J cubic foot of air. 

The fruit would evidently never become dry if the air loaded 
with such moisture remained stationary, but set it in motion with 
a velocity of 880 feet per minute, which is equal to 20 miles per 
hour, and the cause of the rapid drying, or, in other words, of 
the withdrawal of water, becomes apparent. Xow if we figure 
to ourselves an apparatus of 225 cubic feet content, the air heated 
to 212 F. in it contains, according to the above statement, 60 
pounds of water, 50 pounds of which have been withdrawn from 
the fruit, while the remaining 10 pounds were contained in the 
air prior to its entrance into the apparatus, because its tempera- 
ture is supposed to be 62.5 F. With sufficient circulation to 
empty the apparatus every 20 minutes, 150 pounds of water will 
each hour be carried from a quantity of fruit supposed to amount 
to 800 pounds. Hence, in 5 hours, the time generally required, 
for apples, 750 pounds of moisture could be removed if present. 

Moreover, reference to a drying apparatus is not required to 
prove that heat alone does not suffice for drying. Is it not the 
wind which dries up the puddles after a rain more quickly than 
the hottest rays of the sun? The sun alone would effect nothing 
else but envelop the moist earth in a dense mantle of vapor de- 
structive to both men and animals. Thus in the drying appa- 
ratus also it is rather the current of air which dries than the heat, 
but, of course, both must work in conjunction. The rapidity of 
the process prevents decay, and causes the color and aroma of 
the fresh fruit to be retained. The greater advantage of this 
rapidity consists, however, in the conversion of a considerable 
quantity of starch into sugar, which in sweet fruits, such as 
peaches, is sometimes formed in such abundance as to appear in 
small congealed drops upon the surface. 

From the preceding it will also be readily understood why 
drying in the sun or in the oven must yield unsatisfactory re- 
sults. Even with favorable weather the process lasts about 14 
days ; during this long time a fermentation sets in which par- 
tially destroys the content of sugar, and essentially changes the 
color and taste in an unfavorable direction. Such fruit when 



406* VINEGAR, CIDER, AND FRUIT-WINES. 

boiled tastes as if it had been preserved after the appearance of 
decay. Besides, during this process, the fruit is frequently 
selected as a breeding place by insects, in consequence of which it 
soon spoils, and when shipped to a distance resembles on arrival 
at its place of destination a heap of maggots. Such cases are not 
rare, especially if the dried fruit is shipped to tropical countries. 

Drying in the oven has the disadvantage that the dry heat imme- 
diately closes the pores of the fruit, thereby rendering the escape 
of the internal moisture very difficult. If the heat is not very 
strong the fruit remains moist in the interior, which causes it to 
spoil, and with a strong heat the surface carbonizes more or less. 
A portion of the sweetness is lost by being converted into cara- 
mel, the appearance of the fruit suffers by the tough shrivelling of 
the surface, and the taste is injured by carbonization. 

All these disadvantages are avoided by the modern evapo- 
rating process, which may be called a preservation of the fruit 
in its own juice with the assistance of steam. 

A chemical analysis of a parcel of Baldwin apples shows best 
the changes effected in the composition of fruit by drying in the 
oven and by evaporation, and how the results with these two 
methods compare with each other. The first column gives the 
composition of 500 parts of fresh Baldwin apples. The second 
column gives the composition of the same parcel of apples after 
being reduced to 100 parts (loss of 400 parts of water) by drying 
in the oven, and the third column the result of 100 parts of the 
same parcel reduced by evaporation. 



Water (free and fixed) . 


Fresh. 

. 411.15 
9 60 


Dried in 
the oven. 
12.42 

10 54 


Evapo- 
rated. 
16.62 
10 22 


Starch .... 
Protein .... 
Pectine .... 
Gum .... 


. 32.95 
. 0.75 
. 12.35 
. 6.75 
6.70 


30.95 
0.80 
11.35 

7.22 
4.88 


29.75 
0.76 
10.88 
4.33 
3.43 


Mineral constituents 
Chlorophyl 
Dextrin .... 


. 0.85 
. 0.15 


0.87 
0.12 
2.10 


0.78 
0.15 


Grape sugar . 
Volatile oils, traces 


. 18.75 


18.75 


23.08 



500.00 100.00 100.00 



EVAPORATION OF FRUIT. 



407 



Fig. 76. 



Attention must especially be drawn to the fact that dextrin, 
the formation of which is due to dry heat, is only found in the 
second column, and must be considered 
as an essential disadvantage of drying 
in the oven. The absence of this sub- 
stance in evaporated fruit, as well as 
the presence of a larger quantity of 
water (chemically fixed), is to be as- 
cribed to the influence of moisture dur- 
ing evaporation. 

A presentation of the process of evapo- 
rating fruit must be preceded by a de- 
scription of the apparatus used. Fig. 
76 shows the Alden apparatus as re- 
cently perfected. A is the air-furnace, 
which is formed by the fire-box Z>, the 
ash-box D v and the doubled horizontal 
pipes G, of which, according to the size 
of the apparatus, there are from 3 to 6, 
each 4 inches in diameter, and running 
parallel to each other ; the products of 
combustion pass through them in the 
direction of the arrows, and escape 
through the smoke-pipe at the back 
of the apparatus. The fire-box is sur- 
rounded with an air-space provided at Mwith apertures. Similar 
apertures to permit the entrance of cold air are provided on the 
side near the foot of the brick casing. The cold air comes first 
in contact with the lower, only moderately heated, pipes, then 
rises to the second, and finally to the third and hottest series of 
pipes. It is thus gradually heated, and the pipes lying close to- 
gether, each atom of air comes in contact with them, which is con- 
sidered a better mode of heating than by radiation, formerly used. 
The pipes are of cast-iron, and an escape of smoke into the dry- 
ing-tower is impossible. By always keeping the pipes clean, 
which -can be conveniently done, the heat passes rapidly through 
their walls, and ascends immediately into the drying-tower with- 
out the possibility of super-heating. 




408 VINEGAR, CIDER, AND FRUIT-WINES. 

The draught-pipe d connects the exit of the drying-tower with 
the fire-box of the furnace. The importance of this ventilation is 
sufficiently shown by the statement that for combustion 25,000 
cubic feet of air per hour are required, which are introduced from 
the neighborhood of the opening of the tower through the pipe d 
into the fire-box. The removal of such a considerable quantity 
of air produces a vacuum in the upper portion of the tower, and 
consequently a very quick current of air over the trays of fruit 
in the tower an absolute requirement for attaining great perfec- 
tion in the art of drying fruit by evaporation. Besides, a saving 
of fuel is effected by the introduction of air already heated into 
the fire-box. The smoke-pipe is surrounded by a wooden 
jacket leaving a small intermediate space in which the heat radi- 
ating from the pipe collects, and is forced to enter the tower be- 
low the discharge-door. This also accelerates the current of air 
in the tower and prevents the condensation of the moisture, so 
that the fruit completely dries off in a short time. The branch- 
pipe / connects the opening of the tower with the smoke-pipe, 
which by its power of absorption also increases the current of air. 
The <Jraught-pipe c is provided, as will be readily seen, for the 
purpose of uniformly distributing the heat in the tower. 

The bulb of the thermometer, with which the apparatus is pro- 
vided, is placed in the interior of the tower and the scale on the 
outside, so that the temperature can be read off without opening 
a door, whereby cold air would enter, which must be avoided. 
The air-furnace is constructed of brick, and the tower, as well as 
the draught-pipes d and c and the jacket of the smoke-pipe 0, of 
double boards. 

The hurdles or trays for the fruit consist of wooden frames 
with galvanized iron wire bottoms. They hold from 20 to 60 
Ibs. of fruit each, and when charged are pushed through the door 
over the air-furnace into the tower, where they rest upon pins of 
an endless chain set in motion by a wheel, as seen in the illustra- 
tion. The trays sit close to the walls on two sides of the tower, 
while in the other direction there is an interspace of two inches. 
The first tray is pushed tight against the back wall, the men- 
tioned interspace thus remaining in front of the door. 

After six to ten minutes, according to the variety of fruit, the 



EVAPORATION OF FRUIT. 409 

tray is raised five inches by means of the endless chain ; the second 
tray is then placed in position, but so that the above-mentioned 
intermediate space is at the back wall. At regular intervals the 
trays, when placed in position, are raised by the endless chain 
and the fresh trays pushed in, so that they touch alternately the 
front and back wall, the current of hot air being thus forced 
to ascend in a zigzag. When the tower is filled with trays it 
contains taking apples as an example from 1200 to 3000 Ibs. 
of fruit, every 50 Ibs. of each yield from 40 to 45 Ibs. of water, 
which ascends as vapor, which by surrounding the fruit with a 
moist mantle prevents its burning and keeps the pores open. 
When the tray first placed in position arrives at the discharge- 
door it has been in the tower for about five hours, and its contents 
have been converted into evaporated fruit which will keep for 
many years. Thus fruit can be gathered, evaporated, and sold 
all in one day. 

By considering the construction of the tower it will be seen 
that the fruit during its ascent remains in a uniform moisture and 
heat, so that up to the moment it is taken from the apparatus, its 
content of water can escape through the opened pores and, on the 
other hand, the heat can act to its very centre. A uniform, per- 
fect product can be obtained only by these means. When the 
fruit arrives at the discharge-door it is cool and as soft as fresh 
fruit. 

We will here call attention to a sun-drying apparatus, shown 
in Fig. 77, which may be recommended to those who do not 
wish to employ artificial heat, and are forced to give the prefer- 
ence to as cheap an apparatus as possible. The apparatus is con- 
structed of boards and window-glass. The board walls, which 
are somewhat inclined outwardly, project above the panes of 
glass and serve, as is readily seen, for catching the rays of the 
sun. .They are lined inside with tin, thus becoming reflectors. 
The side door serves as an entrance to the apparatus when the 
panes of glass are to be cleansed or repairs are to be made in the 
interior. The trays containing the fruit are pushed in from the 
back, the entrance of each tray being covered by a wooden flap. 
According to the size of the apparatus two or three rows, each 
consisting of twelve trays, are placed alongside each other. Above 



410 VINEGAR, CIDER, AND FRUIT- WINES. 

the uppermost entrances for the trays are slides, which can be 
opened or closed according to whether the heat in the interior is 
to be increased or moderated. 

Fig. 77. 




The apparatus stands upon a turn-table, so that the front can 
from morning to evening be exposed to the full rays of the sun. 
When the latter no longer reach the apparatus the reflectors, 
which are hinged, are laid over the panes of glass, which pre- 
vents the radiation of heat and protects the fruit from dew. 

The time required for drying fruit in this apparatus cannot, of 
course, be definitely stated, but on an unclouded hot summer day 
apples pared by a machine can be dried in eight hours. The 
product obtained is not of as good a quality as evaporated fruit, 
but it is incomparably superior to that produced by the primitive 
method of drying in the open air or in the oven. 

Referring back to the Alden apparatus previously described, it 
remains to be said that there are a number of other evaporators 
based upon the same principle but with various modifications and 
improvements. 

Fig. 78 shows the improved Williams evaporator manufactured 
by S. E. Sprout, of Muncy, Pa. The apparatus is heated by 
steam radiators located at the base of the vertical tower, and has 
vertical radiating pipes up the centre of the vertical tower, around 
which the trays of fruit revolve, with deflectors at intervals of 
two feet projecting from each side of said pipes to direct the heat 



EVAPORATION OF FRUIT. 

Fig. 78. 



411 




under the trays of fruit as they revolve around the pipes. (The 
trays and hanger are left out in the illustration to show the in- 



412 



AND FRUIT-WINES. 



terior arrangement of the pipes.) These pipes or radiators ex- 
tending up the tower from bottom to top produce a uniform heat 
the entire length of the tower, and increase the draught by increas- 
ing the heat at the top, which produces a more rapid circulation 
than when the heat is all at the bottom, as with the hot-air fur- 
nace ; and the capacity of the apparatus is also increased in pro- 
portion to the increase of the heat and the draught through the 
tower. The trays of fruit in passing up the tower are exposed 
from one side to the pipes, and on descending are exposed 
from the other, which causes the fruit to dry uniformly. The 
tower being vertical the heat is utilized until it reaches the 
top. In this apparatus a very strong heat can be had through- 
out the entire length of the tower, without incurring any risk of 

Fig. 79. 




fire from sittings from the trays, when drying cores and skins, 
falling on the hot-air furnace, which is always placed directly 
under the tower. Several sizes of this evaporator are manufac- 
tured. 

Fig. 79 shows the American fruit evaporator, several sizes of 



EVAPORATION OF FRUIT. 413 

which are manufactured by the American Manufacturing Com- 
pany, of Waynesboro, Pa. It differs from the preceding in 
having an inclined trunk. The advantages claimed for it by the 
manufacturers are that separate currents of pure, dry air, auto- 
matically created, pass underneath and diagonally through the 
trays and then off over them, carrying the moisture out of the 
evaporator without coming into contact with the contents of the 
trays previously entered. The greatest heat is concentrated upon 
each tray or group when first entered, these in turn being moved 
forward into a lower temperature by those entered in sequence, 
hence no steaming or cooking becomes possible. The evaporator 
shown in the illustration is 9 \ feet long and 28 inches wide ; it 
has 22 trays of galvanized iron cloth, and a capacity of 10 to 12 
bushels of apples per day. It consumes about 80 pounds of coal 
or its equivalent in wood or coke. The furnace supplies strong 
currents of dry, hot air, which pass through the two chambers of 
the evaporator-trunk and carry off the moisture or vapor dis- 
charged from the fruit over and above the line of trays in each 
chamber. jSTo steaming, cooking, or retrograde or diffusive 
features attend the operation. The trays in groups of two at a 
time are entered in front in the upper (hotter) chamber and 
moved forward by insertion of the next group, and finished in 
the lower chamber and at a lower temperature. Thus the process 
is continuous, and each tray receives the same treatment and con- 
ditions, viz., greatest heat when first inserted, and finishing at a 
gradually lowering temperature and safety from scorching. The 
evaporators are manufactured in several sizes ranging in price 
from $25 to $450, and for extensive commercial plants with 
sundry modifications and mechanism for coffee, tea, etc., of great 
capacity costing $1000 and upwards. 

The manner of operating the Alden apparatus is as follows : 
The maintenance of a uniform temperature in the tower being 
essential, the thermometer should indicate 194 to 212 F. ; ber- 
ries and stone fruit are to be kept somewhat cooler. The intro- 
duction of too much cold air into the air-furnace must be avoided. 
As a rule an aperture two feet square suffices. 

The upward motion of the trays must be effected at regular in- 
tervals. How long these intervals are to be cannot be definitely 



414 



VINEGAR, CIDER, AND FRUIT-WINES. 



stated, it depending on the content of water in the fruit and on 
the temperature of the tower. The following table may, how- 
ever, serve as a guide : 



interval 6 to 10 minutes. 



8 


12 


12 


20 


15 


20 


8 


15 


10 


20 


10 


20 


6 


8 


5 


7 


12 


20 


20 


25 



Apples 

Pears 

Peaches 

Stoned plums 

Apricots 

Stoned cherries . 

Berries 

Potatoes 

Green corn 

Onions 

Tomatoes 



It is supposed that the temperature directly above the air-fur- 
nace is 212 F., and it is best to keep it that degree except for 
berries and stoned fruit, for which it may be from 41 to 50 less. 
As previously stated, it is an essential condition that the fruit 
should not boil. This will, however, not be the case at the tem- 
perature mentioned because the fruit remains too short a time in 
it, and in rising upwards meets a somewhat more moderate heat. 
As a rule it may be said that as high a temperature as possible is 
most advantageous provided boiling be avoided. 

The evaporated fruit when taken from the tower is spread out 
in an airy room, where it remains for a few hours to dry off. 
Care must be had that during this time it does not come in contact 
with insects, and to prevent this the windows and air-holes must 
be provided with screens or the fruit covered with musquito 
netting. The fruit when ready for packing is put up in boxes as 
follows : Line the box with colored paper with the ends pro- 
jecting above the edge. Then fill the box with fruit; kernel 
fruit is piled up about one inch above the edge of the box while 
stone fruit is not piled so high, it being subsequently not subjected 
to pressure. To press down the contents even with the edge of 
the box a weight, or, still better, a press is used. After pressing 
fold the ends of the paper over the fruit, nail down the lid, and 
put on the label. 

Sliced evaporated apples are packed as follows : Line the box 
with white paper, one piece on the bottom and four pieces on the 



EVAPORATION OF FRUIT. 415 

sides long enough to fold over. Then nail down the lid, take off 
the bottom, and commence packing by placing one layer of slices 
in the manner of roof-tiles. Sufficient fruit to make up the re- 
quired weight is then piled in, and after pressing down the box is 
nailed up and labelled. A general rule as regards weight has not 
been introduced, though in California all varieties of evaporated 
fruit are packed in boxes holding 50 pounds net. 

Now a few words in regard to the varieties of fruit to be used. To 
be sure every kind of fruit can be evaporated, but poor qualities 
remain bad after evaporation. No one who wishes to be success- 
ful in the business should for one moment entertain the idea that 
fruit unpalatable in a fresh state is good enough for evaporating. 
For commercial purposes the selection of varieties must be made 
as carefully as for fresh fruit, or, briefly stated, only table fruit 
should be evaporated, this referring especially to apples and pears, 
of which the mellow and luscious varieties alone should be se- 
lected. The intelligently conducted evaporating establishments in 
this country are very careful in this respect, they having like the 
canning establishments certain favorites, for instance, of apples, 
the Gravenstein, Red Astrachan, Autumn Pippin, Newtown Pip- 
pin, Bellflower, Baldwin, Northern Spy ; of pears, the Bartlett, 
Autumn Butler Pear, Clapp's Favorite ; of plums, Reine Claude, 
Coe's Golden Drop, Columbia, Washington ; of cherries, Royal 
Ann and Elton. No discrimination is made in regard to berries, 
peaches, and apricots, all varieties being used. 

Apples should be pared with a machine and sliced. So many 
different styles of apple parers are in the market that it is diffi- 
cult to say which is the best. One which pares, cores, and slices 
the apple at one operation should be selected. Pears are better 
pared by hand, and peaches with a rotary knife parer. 

Stone-fruit is sometimes stoned, which is effected with the well 
known stoning machine, but as the different kinds of machines in 
the market are by no means perfect, it is best for prime ware to 
remove the stones by hand until some ingenious head invents a 
machine which will bruise the fruit as little as the human hand. 

Apples and pears when pared acquire a brown coloration, which 
is not lost by drying no matter by what method. Now how is it 
that many apples and pears of a white yellow or pale yellow 



416 VINEGAR, CIDER, AND FRUIT- WINES. 

color are brought into the market ? The color has nothing to do 
with the quality of the product, but its sale depending on its ap- 
pearance the apples and pears are bleached before^ evaporating. 
The process is very simple : a number of trays are placed on top 
of each other, and a bundle of sulphur matches ignited under 
them. Sometimes lime is slacked under such a pile of trays, the 
fruit being in both cases bleached by the ascending vapors. Others 
again place the fruit for some time in a water-bath impregnated 
with sulphur. These methods are mentioned, not to recommend 
them, but rather to warn against them, and, besides, because it is 
frequently believed that the pale color of the fruit is due to a 
more perfect method of drying. The use of sulphur for this 
purpose deserves censure, it being injurious to health, and the con- 
sumer should prefer naturally colored evaporated fruit to the 
bleached article, which is readily recognized by its pale color. 
There is but one method leading to the same result which can be 
unhesitatingly used, that is, to throw the fruit when pared into 
salt water, where it is allowed to remain until placed in the trays. 
The color is not as pale as that obtained by bleaching, but it is 
more natural which, in our opinion, is an advantage. Decay set- 
ting in immediately after the fruit is cut, it should be brought 
into the evaporating tower as soon as possible. A warm salt- 
water bath is also frequently used for stone fruit which is to be 
evaporated without removing the stones, in order to better retain 
its natural appearance. The same purpose can, however, be 
better attained by the use of a bath of lukewarm or cold alum 
water, which can also be advantageously employed in preserving 
the fruit in jars and cans. Plums after evaporating are generally 
brought into a bath of sugar-water in order to give them the lus- 
trous and uniformly dark appearance observed in French prunes. 
For this purpose brown sugar is dissolved in an equal quantity 
of hot water, and the prunes in a wire basket submerged in the 
bath for half a minute. They are then spread out upon hurdles 
and packed when perfectly dry. 

The trays which are to be placed in the evaporating tower 
must not be loaded too heavily with fruit. Stone-fruit not freed 
from the stones js placed close together with the stem end upwards, 
but only in one layer. Quartered or halved stoned-fruit, as well 



EVAPORATION OF FRUIT. 417 

as sliced apples, are placed close together edge upward until the 
bottom of the tray is covered. Sliced pears are arranged in a 
similar manner. Of berries several layers an inch deep may be 
made, but they must be covered with tissue-paper. Grapes are 
but seldom converted into raisins in the evaporating apparatus, 
because the process would require 40 hours, it being impossible to 
use a temperature exceeding 176 F. Hence it is considered more 
advantageous to dry grapes in the sun. For the northern limits 
of grape-culture the evaporating process for raisins may, however, 
prove of great importance if only for supplying the home market, 
especially when experience shows, as it has during the last 
few years in California, that the production pays on an average 
better than that of wine. It need only be remembered that the 
principal producers of raisins, the Spaniards and Greeks, are 
entirely dependent on the weather, which frequently causes them 
heavy losses. The evaporating apparatus, however, makes the 
manufacturer independent of the weather, and no Spanish or Greek 
sun is required for the production of excellent raisins. 

Tomatoes are peeled but not sliced, and placed close together 
in one layer in the trays. Pumpkins are peeled and cut in pieces 
two or three inches thick. For several years a flour has been made 
from the dried pieces which serves as a substitute for rice flour. 
Sweet potatoes are treated in a similar manner, their flour serving 
as a substitute for chicory. 

Green corn is first steamed on the ear for not more than five 
minutes. The grains are then picked off, placed in two-inch deep 
layers in the trays and thoroughly evaporated, but not at too high 
a temperature, 185 to 194 F. being sufficient. When dry it 
is rubbed and passed through a fanning-mill to remove the hulls 
loosened by rubbing. It is packed in boxes holding 10, 20, and 
50 Ibs. each, and brings wholesale from 10 to 12 cents per pound. 

The following must also be steamed before evaporating : green 
peas and beans, asparagus, beets, carrots, lettuce, cabbage, and 
parsnips. Vegetables are cut up with a cabbage-cutter, and roots 
in slices like apples. 

Onions are first freed from their external red or yellow peel and 
then cut into slices one-fourth inch thick with a cabbage-cutter. The 
slices are steamed for five minutes, which, with a suitable steaming 
27 



418 VINEGAR, CIDER, AND FRUIT- WINES. 

apparatus, is best effected by spreading the slices in a two-inch deep 
layer in the trays, placing the latter in the steaming apparatus, and 
immediately after the above mentioned time in the evaporator. 
They are packed in tin boxes holding 50 Ibs. each, which are 
placed in a wooden box. By evaporation, 100 Ibs. of onions are 
reduced to 12 ibs. The average wholesale price is about 30 
cents per pound. 

Potatoes must be thoroughly washed. This is best effected in 
a cradle, the bottom of which is provided with wide perforations 
so that the water constantly pouring in can run off quickly. The 
potatoes are then placed in trays, and from four to six of the latter, 
according to the size of the steaming apparatus, brought into the 
boiler. Steam is then admitted, and after 35 minutes the potatoes 
are taken out, care being had, however, not to steam them much, 
as otherwise they become of no value for the evaporating process. 
The loosened peels are then rubbed off with the hand, and the 
peeled potatoes brought into a press, the bottom of which consists 
of a perforated wooden plate or of woven wire. The lid must fit 
tight to the interior walls of the press, so that the entire mass of 
potatoes falls coarsely crushed through the bottom. The crushed 
potatoes are placed in layers two or three inches deep in the trays 
and levelled with an instrument made by driving small nails into a 
board so that their points project one-half inch. They are then 
evaporated at not too high a temperature 185 F. is sufficient 
to prevent scorching; taking care, however, to dry them through. 
The evaporated mass is coarsely ground in a suitable mill, and the 
resulting flour packed in zinc canisters, holding 28 and 56 Ibs. 
each. Two such canisters are placed in a wooden box, and are 
then ready for shipment. 

It is of the utmost importance to select only perfectly sound 
potatoes and remove all which sour or are injured in any other 
way during the process. Success depends on the rapidity and 
regularity from the commencement to the end of the process. All 
potatoes which become cold before being brought into the evapo- 
rating apparatus are worthless, and the same may be said of those 
which have been steamed too long ; they are converted into paste. 

From a statement by an English commission house, in reference 
to a shipment of evaporated potatoes from the Pacific coast, it was 



EVAPORATION OF FRUIT. 419 

learned that the price obtained was 40 shillings for 110 Ibs. The 
commission, freight, etc., of the entire shipment of 20 boxes, each 
containing 108 Ibs. net, amounted to 5 1/w. Id. Annexed to 
the statement was the following suggestion : The potatoes should 
be packed in canisters holding 5(j Ibs. and made of black sheet- 
iron painted red on the outside. In the top should be a round 
hole large enough to admit the hand, and closed by a slide. A 
large label with the words " Preserved Vegetables" should be 
pasted on the side of the canisters. 

The bushel of potatoes in an evaporated state and ready for 
shipment costs about 50 cents. 

In conclusion it remains to say a few words about drying fruit 
in the oven, and we describe the French method, which is decidedly 
the best, as proved by the prunes brought into market from that 
country. The prunes having been sorted by a machine into three 
qualities are placed upon trays and exposed to the sun until the 
skin commences to shrivel. They are then placed in a bake-oven 
previously used for baking bread. If no bread is to be baked, 
the oven is very moderately heated to prevent the rapid (dosing of 
the pores and the formation of a crust upon the surface. They are 
allowed to remain in the oven for 12 hours when they are taken 
out, and when perfectly cold, moistened with alum water and re- 
placed in the oven, which must now be somewhat hotter. After 
12 hours they are again taken out, moistened with alum water, 
and replaced for the third and last time, together with a dish full 
of water, in the oven which must now be still hotter than before. 
The prunes when taken from the oven are submerged fora short 
time in a bath of sugar-water, and are then packed in boxes. It 
will be seen that this process is quite tedious, and the product as 
shown at the Paris Exhibition is not as good as that obtained by 
evaporation. 

Besides prunes the French bring into market dried pears, which 
have also become celebrated. The process is as follows : Fine 
table-pears are pared, quartered, and boiled in sugar syrup ior 
five minutes. They are then placed in a moderately warm oven, 
where they remain for 12 hours ; they are then taken out, allowed 
to cool off, and replaced in the oven, which must now be hotter 
than the first time, until sufficiently dried. 



420 VINEGAR, CIDER, AND FRUIT-WINES. 

The French method can be recommended, but it would be still 
better if it were executed in the improved manner practised here 
and there in central England and in the New England States. 
This improvement consists in the previous boiling of the fruit, 
which must, however, not be continued longer than five minutes. 
The fruit is not gradually heated but submerged in boiling water 
for five minutes, and, without being allowed to cool, brought at 
once into a moderately hot oven. Steaming instead of boiling 
the fruit is still better. It should be exposed to the steam for 
not longer than five minutes, and must then as quickly as possible 
be brought into a moderately hot oven. 



CHAPTER XXXI. 

PREPARATION OF PICKLES AND MUSTARD. 

Pickles. Enormous quantities of pickles are brought into com- 
merce, especially by American and English factories. The most 
remarkable varieties are piccalilli or Indian pickles, mixed pickles, 
and walnut pickles. The packing is always the same ; some of 
the oldest and largest English factories still adhere to stoneware 
pots, which have the advantage of entirely excluding the light 
from the product, thus contributing to its keeping quality. Both 
the French and Americans use glass bottles, the chief 'difference 
being in the diameter of the mouth, which is smaller in the 
American bottles. The latter style is to be preferred, because in 
the former the pickles, when frequently opened, are more exposed 
to the air than is good for them. Stone pots, which are no doubt 
best for family use, are too expensive for commercial purposes, not 
only as regards the first cost, but also on account of their weight, 
which increases the cost of transportation. The bottles are always 
provided with neat labels, and the corks generally covered with 
tin-foil. 

The following general rules apply to the preparation of pickles : 
The best quality of fruit must be gathered at the right time, 
washed in fresh cold well-water, and placed for some time in 



PREPARATION OF PICKLES AND MUSTARD. 421 

strong brine. They are then laid upon fruit hurdles to com- 
pletely dry in the air, and finally brought into the bottles which 
must be nearly filled. The interspaces are then filled up with 
hot-spiced vinegar, and the bottles immediately corked, and, when 
cold, sealed. Strong vinegar must be used, the manufacturers gen- 
erally employing wine-vinegar, known in commerce as No. 24. 
Fruit-vinegar, clarified and spiced and evaporated to three- 
fourths its volume, also answers very well. Pickles for immediate 
use are soaked in hot brine, but as a commercial article they must 
be treated with cold brine only. Moreover, hot brine must not be 
used for fruits of a soft and juicy nature such as cabbage and cauli- 
flower ; and besides cold or only slightly heated vinegar should be 
poured over such articles. Soft and delicate fruits must, as a rule, 
not remain as long in the brine as hard and coarse-fibred ones ; and 
the softest are most advantageously pickled by pouring cold spiced 
vinegar over them. The same may be said of red beets and other 
roots which are cut into strips. Sometimes the spice is put whole 
into the bottle, but it is better and more economical to bring it 
powdered into the vinegar while heating the latter, or if the 
vinegar is to be used cold, to previously boil the powdered spice 
in a small portion of the vinegar, and when cold add it to the 
rest. The spiced vinegar is prepared as follows : 

To 1 quart of vinegar add 2-J ounces of salt, J ounce of black 
pepper, and 2J ounces of ginger. Let the mixture boil up once 
or twice in an enamelled iron pot, filter through a flannel cloth, 
and pour the liquid, hot or cold, over the fruits. 

For a more strongly spiced vinegar reduce in a mortar 2 ounces 
of black pepper, 1 ounce of ginger, and J drachm of cayenne 
pepper, and for walnuts, 1 ounce of eschalots, and add to the mix- 
ture in a stoneware pot 1 pint of vinegar, and tie up the pot with 
a bladder. Place the pot for three days near the fire, shaking it 
several times, and then pour the contents upon the fruits by al- 
lowing it to run through a filtering cloth. 

In the preparation of pickles the use of metallic vessels must be 
avoided, the vinegar as well as the brine dissolving copper, brass, 
and zinc, and becoming thereby poisonous. Ordinary earthen 
pots should also be mistrusted. Stoneware pots, which can be 
heated in a water-bath or upon a stove, are best for the purpose. 



422 VINEGAR, CIDER, AND FRUIT-WINES. 

Moreover, air and light must be kepi away from the pickles as 
much as possible, and they should be touched only with wooden 
or bone spoons. An essential condition for success is to treat the 
fruits immediately after being gathered. The method of some 
manufacturers, who add verdigris to the pickles or boil the vine- 
gar in a copper boiler until it is sufficiently " greenish" to com- 
municate its green color to the product, cannot be too strongly 
condemned. That this crime against the health of the consumer 
is unfortunately committed to a considerable extent, is conclusively 
proved by numerous chemical examinations recently made in the 
large cities of Europe and the United States, and undertaken with 
the laudable purpose of bringing the adulterators of food to jus- 
tice. Many of the pickles in the market, and most of the im- 
ported canned peas, contain copper, and this notwithstanding the 
fact that there are very innocent means for coloring pickles green, 
it being only necessary to put a handful of spinach or wine leaves 
in the boiling vinegar which acquires thereby a green coloration 
and communicates it later on to the pickles. 

The following list comprises the fruits which are chiefly used 
for the preparation of pickles in factories : 

Barberries. The berries are gathered before they are ripe and 
washed with salt water. The vinegar is added cold. 

Beans. Cold vinegar is poured over the young pods, previously 
soaked in cold water. 

Cabbage , red and white. The heads are cut up into fine strips 
which are placed in a strong brine for two days, then dried upon 
hurdles for 12 hours, next brought into bottles, and after pouring 
cold vinegar upon them, at once sealed up. 

Cauliflower. The heads are broken up into small pieces which 
are placed in brine, and finally treated with hot vinegar. 

Cucumbers. Young cucumbers are placed in salt water for one 
week. The brine is then poured of! and after being made boiling 
hot is poured back over the cucumbers. The next day the cu- 
cumbers are dried upon a sieve, slightly rubbed off with cloth, and 
then boiling vinegar is poured over them. 

Elderberry flowers. The umbels are gathered just before the 
flowers open, and treated in the same manner as cauliflower. These 
pickles are much liked in England. 



PREPARATION OF PICKLES AND MUSTARD. 423 

English bamboo. Young elder shoots are freed from the bark, 
placed in a brine for 12 hours, and after drying brought into bot- 
tles, and hot vinegar is poured over them. They are highly es- 
teemed as an addition to boiled mutton. 

Gooseberries. The unripe fruits are treated like cauliflower. 

Mixed pickles. Components : White cabbage, cauliflower, bean 
pods, cucumber, onions. They are prepared like cucumbers. 

Mushrooms. Wash young mushrooms the size of coat buttons 
in cold water, and carefully dry them with a cloth. Then put 
them into a bottle, and pour boiling vinegar over them. 

Onions. Small onions are peeled, and hot vinegar is poured 
over them ; sometimes the onions are previously placed in brine 
for one day. 

Peaches. The fruits, not entirely ripe, are treated like cucum- 
bers. 

Peas are treated like beans and cauliflower. 

PicaliUy. Take one head of white cabbage cut up into fine 
strips, 2 heads of cauliflower broken into small pieces, some bean 
pods, 1 root of horseradish cut into strips, 2 dozen of small white 
onions, and 1 dozen small cucumbers ; pour boiling brine over 
them, and dry them the next day upon a sieve. Then put the 
mixture into a pot and add garlic, ginger, mustard-seed, all 
comminuted, of each 1 ounce, capers J ounce, red pepper \ ounce, 
and pour boiling vinegar over it. Tie up the pot with a bladder, 
let it stand for 4 weeks, shaking it occasionally, and then distrib- 
ute the contents into bottles. 

Tomatoes must not be entirely ripe ; they may be even green 
and half grown. They are pickled in the same manner as 
cucumbers. 

Walnuts. Place the young, soft nuts in strong brine for one 
week, then dry upon a sieve and pour hot vinegar over them. A 
better method is to expose the walnuts, after they have been in 
the brine for nine days, upon a cloth to the sun until they are black, 
and then put them into bottles, which are filled up with hot 
vinegar. These pickles are much liked with fish, and when well 
sealed and stored in a dark place keep for ten years. If they are 
to be used in the first three months after being made, the brine 
must be heated for one hour. 



424 VINEGAR, CIDER, AND FRUIT-WINES. 

Mustard. Mustard of commerce is the seed, whole or ground, 
of several species of the genus Brassica, cruciferous plants which 
grow wild and are cultivated under very various conditions. The 
two common varieties are the black or brown mustard, which has 
a very small seed, and furnishes the most aroma, and the white, 
which is two or three times as large, often used in the whole 
condition in pickles and ground, either by itself or oftener in 
mixture with the brown seed, for the purpose of obtaining the 
desirable qualities of both. 

The most rational manner of preparing mustard for table use 
has been introduced into the English factories. The seed is freed 
from the husk, ground to flour, and the fat oil, which can be used 
as an illuminating oil, pressed out. Generally speaking, the 
preparation of mustard consists in several times grinding in a 
mill a mixture of white and brown mustard with an addition of 
wine-must, either fresh or strongly boiled down, or of wine vine- 
gar until it forms a moderately fine or very fine pasty mass, and 
adding different substances as a seasoning. In the Diisseldorf 
mustard the seasoning consists of cinnamon, cloves, and sugar, in 
the Frankfort mustard of cloves, allspice, and sugar, in the Eng- 
lish mustard of wheat flour, common salt, and pepper, and in the 
French mustard of tarragon, ginger, cinnamon, thyme, marjoram, 
onions, garlic, cloves, etc. An addition of flour is almost gener- 
ally made, as it modifies the sharpness of the mustard and holds 
the mass better together. The quantity of the constituents vary ; 
the usual proportions being from 20 to 30 per cent, of white, and 
5 to 10 per cent, of brown ground mustard, 1 to 2 per cent, of 
common salt, J to J per cent, of pulverized spices, and 40 to 50 
per cent, of must or vinegar. According to the English method 
the use of mustard-seed freed from oil is only recommended. In 
the following a few special receipts are given : 

Gumpoldskirchner must-mustard. Evaporate 30 quarts of 
freshly pressed wine-must to one-half its volume over a moderate 
fire, dissolve in it 5 Ibs. of sugar, and strain the whole over 2 or 
3 roots of horseradish cut in thin slices. Then add in the form 
of fine powder, cardamoms 0.35 oz., nutmeg 0.35 oz., cloves 
0.63 oz., cinnamon 1 oz., ginger 1 oz., mustard-seed, ground 



PREPARATION OF PICKLES AND MUSTARD. 425 

and freed from oil, brown 6 Ibs. and white 11 Ibs. Grind the 
whole several times in a mill and strain. 

Moutard des Jesuites. Make a paste of 12 sardines and 280 
capers, and stir it into 53 ozs. of boiling vinegar, and mix with it 
ground mustard-seed freed from oil, brown 5J ozs. and white 
14J ozs. 

French mustard. Ground mustard 2 Ibs., and J oz. each of fresh 
parsley and tarragon, both cut up fine are thoroughly mixed 
together; further 1 clove of garlic, also cut up very fine, and 12 
salted anchovies. Grind the mixture very fine, add the required 
must, and 1 oz. of pulverized common salt, and for further grind- 
ing dilute with water. To evaporate the water after grinding the 
mustard, heat an iron red hot and cool it off in the mixture, and 
then add wine vinegar of the best quality. 

Ordinary mustard. I. Stir gradually 1 pint of good white 
wine into 8 ozs. of ground mustard-seed, add a pinch of pulve- 
rized cloves, and let the whole boil over a moderate fire. Then 
add a small lump of white sugar, and let the mixture boil up 
once more. 

II. Pour J pint of boiling wine vinegar over 8 ozs. of ground 
mustard-seed in an earthen pot, stir the mixture thoroughly, then 
add some cold vinegar, and let the pot stand over night in a warm 
place. The next morning add J Ib. of sugar, f drachm of pul- 
verized cinnamon, f drachm of pulverized cloves, 1J drachm 
of pepper, some cardamom and nutmeg, half the rind of a lemon 
and the necessary quantity of vinegar. The mustard is now 
ready, and is kept in pots tied up with bladder. 

III. Pound in a mortar the flesh of a salt herring, and 2 ozs. 
of capers to a paste, and mix this with 2 ozs. of pulverized white 
sugar and 13 ozs. of ground mustard seed ; then pour If pint of 
boiling wine vinegar over it, stir, and let the whole stand near a 
fire for several hours. Finally add f pint of boiling vinegar, 
stir thoroughly and pour the mustard into glass bottles. 

Frankfort mustard Mix 1 Ib. of white mustard-seed, ground, 
a like quantity of brown mustard-seed, 8 ozs. of pulverized sugar, 
1 oz. of pulverized cloves, 2 ozs. of allspice, and compound the 
mixture with white-wine or wine-vinegar, 

Wine mustard. Ground mustard-seed, white, 23 ozs., brown 



426 VINEGAR, CIDER, AND FRUIT-WINES. 

12 ozs., common salt 2f ozs., wine-vinegar 8J ozs., a like quantity 
of white-wine, and water 16 ozs. 

Aromatic, or hygienic mustard. Ground mustard-seed, white 23 
ozs., brown 12 ozs., wine-vinegar 17 J ozs. Extract allspice 0.35 
oz., cassia, white pepper, and ginger of each 0.17 oz., with alcohol 
1J oz., and water 8J ozs., add 3J ozs. of common salt and a like 
quantity of sugar, filter the whole and add it to the mustard. 

Diisseldorf mustard. Ground mustard-seed freed from oil, 
brown 3 ozs., white 8J ozs., boiling water 26J ozs., wine-vine- 
gar 18 ozs., cinnammon 0.17 oz., cloves 0.1 oz., sugar 11 ozs., 
white-wine 18 ozs. 

Sour Dusseldorf mustard. Fill 2 casks with vinegar, steep in 
one of the casks 2 Ibs. of origan leaves, and in the other an ordi- 
nary bucket full of onions cut up, and let them digest for 2 days. 
Then braise 44 Ibs. of white mustard-seed and 66 Ibs. of brown ; 
put this in a vat and add 1 Ib. of pulverized cloves, 1J Ib. of 
pulverized coriander-seeds, and 4J gallons of each of the pre- 
pared vinegars. Stir the whole thoroughly and grind it twice 
in a mill. To every gallon of this add and mix thoroughly with 
it 1 Ib. of salt dissolved in 1 quart of the onion vinegar. 

Sweet Kremser must-mustard. Ground mustard-seed, brown 10 
Ibs., white 5 Ibs., is intimately mixed with 3 Ibs. of freshly 
pressed must, and boiled down to the desired consistency. 

Sour Kremser must-mustard. Boil to a stiff paste 15 Ibs. of 
brown mustard ground, and 5 Ibs. of white mustard ground, 
together with 4 Ibs. of must, and after cooling stir in 4 Ibs. of 
vinegar. 

Moutarde de maille. Cut up 8 ozs. of fresh tarragon leaves 
without the stems, 2J ozs. of basil, 2 ozs. of bay leaves and 4 ozs. 
of rocambole (a species of garlic). Place these ingredients in a 
glass alembic, pour 2J quarts of strong wine-vinegar over them, 
and, to allow the vapors to escape, tie up the mouth of the 
alembic with a piece of perforated moist bladder. Place the 
alembic upon hot sand for 4 days, then filter the fluid first through 
linen and then through blotting paper. Add to this aromatic 
vinegar, 1 oz. of common salt, then stir it into a thick paste with 
ground brown mustard-seed, and keep the mustard in earthenware 
jars tied up with bladder. 



PREPARATION OF PICKLES AND MUSTARD. 427 

Moutarde aux epices is prepared by extracting 18 ozs. of tarra- 
gon leaves, 7 ozs. of basil, 1J oz. of bay leaves, 3J ozs. of white 
pepper, If oz. of cloves, and 0.35 oz. of mace with vinegar and 
mixing the extract with mustard prepared in the ordinary manner 
from ground mustard-seed, brown 44 Ibs., white 11 Ibs., and 
vinegar 8J Ibs. 

Moutarde aromatisee. Boil ground mustard-seed, brown 22 
Ibs., white 44 Ibs. with 9 Ibs. of vinegar, and add oil of tarragon 
1 oz., oil of thyme J oz., oil of mace 0.35 oz., and oil of cloves 
0.17 oz., all previously dissolved in very strong vinegar. 

English mustard. Ground mustard-seed 9 Ibs., wheat flour 
9 ozs., common salt If lb., cayenne pepper 2f ozs. } and as much 
vinegar and water as required. 



APPENDIX. 




X<A OF THE 




APPENDIX. 



431 



TABLE I. Hehner's alcohol table. 



, 

L 

J O 

1- 

GO 


Per cent, by weight 
of absolute alcohol. 


Per cent, by volume 
of absolute alcohol. 


> 

"> 
as 

tip* 
" *J 

O. 54 

02 


Per cent, by weight 
of absolute alcohol. 


Per cent, by volume 
of absolute alcohol. 


>> 

I-* 
II 

a* 

DO 


Per cent, by weight 
of absolute alcohol. 


Per cent, by volume 
of absolute alcohol. 


Specific gravity 
at 60 F. 


Per cent, by weight 
of absolute alcohol. 


Per cent, by volume 
of absolute alcohol. 


1.0000 


0.00 


0.00 


0.9957 


2.45 


3.07 


9.9913 


5.06 


6.32 


0.9869 


8.00 9.95 








6 


2.51 


3.14 


2 


5.12 


6.40 


8 


8.07 10.03 


0.9999 


0.05 


0.07 


5! 2.57 


3.21 


1 


5.19 


6.48 


7 


8.14 10.12 


8 


0.11 


0.13 


4 2.61 


3.28 





5.25 


6.55 


6 


8. 21 ' 10.21 


7 


0.16 


0.20 


3 


2.65 


3.35 








5 


8.29 10.30 


6 


0.21 


0.26 


2 


2.71 


3.42 


0.9909 


5.31 


6.63 


4 


8.36 ! 10.38 


5 


0.26 


0.33 


1 


2.78 


3.49 


8 


5.37 


6.71 


3 


8.43 ; 10.47 


4 


0.32 


0.40 





2.84 


3.55 


7 


5.44 


6.78 


2 


8.50 ; 10.56 


3 


0.37 


0.46 








6 


5.50 


6.86 


1 


8.57 


10.65 


2 


0.42 


0.53 


0.9949 


2.89 


3.62 


5 


5.56 


6.94 





8.64 


10.73 


1 


0.47 


0.60 


8 


2.94 


3.69 


4 


5.62 


7.01 











0.53 


0.66 


7 


3.00 


3.76 


3 


5.69 


7.09 


0.9859 


8.71 


10.82 








6 


3.06 


3.83 


2 


5.75 


7.17 


8 


8.79 


10.91 


0.9989 


'0.58 


0.73 


5 


3.12 


3.90 


1 


5.81 


7.25 


7 


8.86 


11.00 


8 


0.63 


0.79 


4 


3.18 


3.98 





5.87 


7.32 


6 


8.93 


11.08 


7 


0.68 


0.86 


3 


3.24 


4.05 








5 


9.00 


11.17 


6 


0.74 


0.93 


2 


3.29 


4.12 


0.9899 


5.94 


7.40 


4 


9.07 


11.26 


5 


0.79 


0.99 


1 


3.35 


4.20 


8 


6.00 


7.48 


3 


9.14 


11.35 


4 


0.84 


1.06 





3.41 


4.27 


7 


6.07 


7.57 


2 


9.21 


11.44 


3 


0.89 


1.13 








6 


6.14 


7.66 


. 1 


9.29 


11.52 


2 


0.95 


1.19 


0.9939 


3.47 


4.34 


5 


6.21 


7.74 





9.36 


11.61 


1 


1.00 


1.26 


8 


3.53 


4.42 


4 


6.28 


7.83 











1.06 


1.34 


7 


3.59 


4.49 


3 


6.36 


7.92 


0.9849 


9.43 


11.70 








6 3.65 


4.56 


2 


6.43 


8.01 


8 


9.50 


11.79 


0.9979 


1.12 


1.42 


5 


3.71 


4.63 


1 


6.50 


8.10 


7 


9.57 


11.87 


8 


1.19 


1.49 


4 


3.76 


4.71 





6.57 


8.18 


6 


9.64 


11.96 


7 


1.25 


1.57 


3 


3.82 


4.78 








5 


9.71 


12.05 


6 


1.31 


1.65 


2 3.88 


4.85 


0.9889 


6.64 


8.27 


4 


9.79 


12.13 


5 


1.37 


1.73 


1 


3.94 


4.93 


8 


6.71 


8.36 


3 


9.86 


12.22 


4 


1.44 


1.81 





4.00 


5.00 


7 


6.78 


8.45 


2 


9.93 


12.31 


3 


1.50 


1.88 








6 


6.86 


8.54 


1 


10.00 


12.40 


2 


1.56 


1.96 


0.9929 


4.06 


5.08 


5 


6.93 


8.63 





10.08 


12.49 


1 


1.62 


2.04 


8 


4.12 


5.16 


4 


7.00 


8.72 











1.69 


2.12 


7 


4.19 


5.24 


3 


7.06 


8.80 


0.9839 


10.15 


12.58 








6 


4.25 


5.32 


2 


7.13 


8.88 


8 


10.23 


12.68 


0.9969 


1.75 


2.20 


5 


4.31 


5.39 


1 


7.19 


8.96 


7 


10.31 


12.77 


8 


1.81 


2.27 


4 


4.37 


5.47 





7.27 


9.04 


6 


10.38 


12.87 


7 


1.871 2.35 


3 


4.44 


5.55 








5 


10.46 i 12.96 


6 


1.94 


2.43 


2 


4.50 


5.63 


0.9879 


7.33 


9.13 


4 


10.54 13.05 


5 


2.00 


2.51 


1 


4.56 


5.71 


8 


7.40 


9.21 


3 


10.62 13. If) 


4 


2.06 


2.58 





4.62 


5.78 


7 


7.47 


9 29 


2 


10.69 


13.24 


3 


2.11 


2.65 








6 


7.53 


9.37 


1 


10.77 


13.34 


2 


2.17 


2.72 


0.9919 


4.69 


5.86 


5 


7.60 


9.45 





10.85 


13.43 


1 


2.22 


2.79 


8 


4.75 


5.94 


4 


7.67 


9.54 











2.28 


2.8b 


7 


4.81 


6.02 


2 


7.73 


9.62 


0.9829 


10.92 


13.52 








6 


4.87 


6.10 


2 


7.80 


9.70 


8 


11.00 


13.62 


.9959 


2.33 


2.93 


5 


4.94 


6.17 


1 


7.87 


9.78 


7 


11.08 


13.71 


8 


2.39 


3.00 


4 


5.00 


6.24 





7.93 


9.86 


6 


11.15 


13.81 



432 



APPENDIX. 



TABLE I. (continued.) 





*."3 


"o 




-w ~ 


0* 




+* o 


<D 




*>"o 


o> "3 




2~ 












rC 














g 




.^S 


ll 




tt o 


3 g 




leg 


Sg 


s 


1| 


?** 


1? 


"3 







1; 


>"* 


*? 


|* 


* 


oJ 


j^3 


.a* " 


o3 


=5 


^3 





^3 


^3 


8 


>"'" 


.a* 3 


li 






i| 




Si 


ttpsj 


|| 


|J 


tt.E< 


|| 


ll 


02 


* 


PL, 


O2 





PL, 


02 


1 


* 


02 


PH 


PH 


0.9825 11.23 13.90 


0.9781 14.73 


18.14 


0.9739 


18.15 


22 27 


0.9695 


21.69 


26.49 


4111.31 


13.99 


14.82 


18.25 


8 


18.23 


22! 3b 


4 


21.77 


26.58 


3 


11.38 


14.09 








7 


J8.31 


22.4b 


3 


21.85 


26.67 


2 


11.46 


14.18 


0.9779 


14.91 


18.36 


6(18.38 


22.55 


2 


21.92 


26.77 


1 


11.54 


14.27 


8 ,15.00 


18.48 


5 


18.46 


22.64 


] 


22.00 


26.86 





11.62 


14.37 


715.08 


18.58 


4 


18.54 


22.73 





22.08 


26.95 








6 15.17 


18.68 


3 


18.62 


22.82 








0.9819 


11.69 


14.46 


5 15.25 


18.78 


2 


18.69 


22.92 


0.9689 


22.15 


27.04 


8 


11.77 


14.56 


4 


15.33 


18.88 


1 


18.77 


23.01 


8 


22.23 


27.13 


7jll.85 


14.65 


3 


15.42 


18.98 





18.85 


23.10 


7 


22.31 


27.22 


6H1.92 14.74 


2 


15.50 


19.08 








6 


22.38 


27.31 


5(12.00 14.84 


1 


15.58 


19.18 


0.9729 


18.92 


23.19 


5 


22.46 


27.40 


4 12.08 


14.93 





15.67 


19.28 


8 


19.00 


23.28 


4 


22.54 


27.49 


3 12.15 


15.02 








7 19.08 


23.38 


3 


22.62 


27.59 


2(12.23(15.12 


0.9769 15.75 


19.39 


6 19.17 


23.48 


2 


22.69 


27.68 


1 


12.31 15.21 


8 15.83 


19.49 


5 


19.25 


23.58 


1 


22.77 


27.77 





12.38 


15.30 


7 15.92 


19.59 


4 


19.33 


23.68 





22.85 


27.86 








o 


16.00 


19.68 


3 


19.42 


23.78 








0.9809 


12.46 35.40 


5 16.08 19.78 


2 


19.50 


23.88 


0.9679 


22.92 


27.95 


8 


12.54 


L5.49 


4 16.15 


19.87 


1 


19.58 


23.98 


8 


23.00 


28.04 


7 


12.62 


15.58 


3 


16.23 


19.96 





19.67 


24.08 


7 


23.08 


28.13 


6 12.69 


15.68 


2 


16.31 


20.06 








6 


23.15 


28.22 


5J12.77 


15.77 


1 16. 38 (20.15 


0.9719 


19.75 


24.18 


5 


23.23 


28.31 


412.85 15.86 





16.46 20.24 


8 


19.83 


24.28 


4 


23.31 


28.41 


312.92 15.96 








7 


19.92 


24.38 


3 


23.38 


28.50 


2 


13.0016.05 


0.9759 16.54 


20.33 


6 20.00 


24.48 


2 


23.46 


28.59 


1 


13.08 16.15 


8 16.62 120.43 


5120.08 


24.58 


1 


23.54 


28.68 





13.15 16.24 


7 


16.69 20.52 


4 


20.17 


24.68 





23.62 


28.77 






6 16.77 


20.61 


3 20.25 


24.78 








0.9799 


13.23 16.33 


5 16.85 20.71 


2 20.33 


24.88 


0.9669 


23.69 


28.86 




13.31 16.43 


4 16.92 20.80 


1 20.42 


24.98 


8 


23.77 


28.85 


7 


13.38 16.52 


3 17.00 20.89 


0(20.50 


25.07 


7 


23.85 


29.04 


6 


13.46(16.61 


o 


17.08 20.99 








6 


23.92 


29.13 


5 


13.54 16.70 


1 


17.17 


21.09 


0.9709 20.58 


25.17 


5 


24.00 


29.22 


4 


13.62 16.80 





17.25 


21.19 


8(20.67 


25.27 


4 


24.08 


29.31 


3 


13.69 16.89 








7 20.75 


25.37 


3 


24.15 


29.40 


2 


13.77 16.98 


0.9749 17.33 


21.29 


6 20.83 


25.47 


2 


24.23 


29.49 


-i 


13.85 117.08 


8(17.42 21.39 


5 20.92 


25.57 


1 


24.31 


29.58 





13.9217.17 


7 17.50 


21.49 


4 21.00 


25.67 





24.38 


29.67 


0.9789 


14.00 i 17.26 


6 17.58(21.59 
6 17.67 21.69 


3J21.08 
2(21.15 


25.76 
25.86 


.9659 


24.46 


29.76 


8 14.09 17.37 


417.75 


21.79 


1 21.23 


25.95 


8 


24.54 


29.86 


7 14.18 


17.48 


3 17.83 


21.89 


0:21.31 


26.04 


7 


24.62 


29.95 


6 14.27 17.59 


2 17.92 


21.99 








6 


24.69 


30.04 


5 14.36 17.70 


1 18.00 


22.09 


0.9699 21.38 


26.13 


5 


24.77 


30.13 


4 14.45 17.81 





18.08 


22.18 


8 21.46 


26.22 


4 


24.85 


30.22 


3 14.55 17.92 








7:21.54 


26.31 


3 


24.92 


30.31 


2 


14.64 


18.03 








6 21.62 


26.40 


2 


25.00 


30.40 



APPENDIX. 



433 



TABLE II. Which indicates the specific gravity of mixtures 

of alcohol and water. 

The figures in the column to the left show the per cent, by volume of alcohol ; 
the figures in the column to the right give the specific gravities which 
correspond to the content of alcohol at 60 F. 





s 




<c 

S 




<v 

s 




* 




j2 




a 




a 




a 




"o 




'o 




"o 




"o 




> 

"3 


Specific 


> 

1 


Specific 


J 


Specific 


> 

3 


Specific 


^.fl 

^B 


gravity at 


JH 

a'! 


gravity at 


a' 


gravity at 


' 


gravity at 


"3 


60 F. 


* 


60 F. 


g* 


60 F. 


s* 


60 F. 


go 




"o 




So 




o 




PH 




<s 




h 




PH 




1 


0.9985 


26 


0.9698 


51 


0.9323 


76 


0:8747 


2 


0.9970 


27 


0.9688 


52 


0.9303 


77 


0.8720 


3 


0.9956 


28 


0.9677 


53 


0.9283 


78 


0.8693 


4 


0.9942 


29 


0.9666 


54 


0.9263 


79 


0.8665 


5 


0.9928 


30 


0.9655 


55 


0.9242 


80 


0.8639 


6 


0.9915 


31 


0.9643 


56 


0.9221 


81 


0.8611 


7 


0.9902 


32 


0.9631 


57 


0.9200 


82 


0.8583 


8 


0.9880 


33 


0.9618 


58 


0.9178 


83 


0.8555 


9 


0.9878 


34 


0.9605 


59 


0.9156 


84 


0.8526 


10 


0.9866 


35 


0.9592 


60 


0.9134 


85 


0.8496 


11 


0.9854 


36 


0.9579 


61 


0.9112 


86 


0.8466 


12 


0.9843 


37 


0.9565 


62 


0.9090 


87 


0.8436 


13 


0.9832 


38 


0.9550 


63 


0.9067 


88 


0.8405 


14 


0.9821 


39 


0.9535 


64 


0.9044 


89 


0.8373 


15 


0.9812 


40 


0.9519 


65 


0.9021 


90 


0.8339 


16 


0.9800 


41 


0.9503 


66 


0.8997 


91 


0.8306 


17 


0.9790 


42 


0.9487 


67 


0.8973 


92 


0.8272 


18 


0.9780 


43 


0.9470 


68 


0.8949 


93 


0.8237 


19 


0.9770 


44 


0.9452 


69 


0.8925 


94 


0.8201 


20 


0.9760 


45 


0.9435 


70 


0.8900 


95 


0.8164 


21 


0.9750 


46 


0.9417 


71 


0.8875 


96 


0.8125 


22 


0.9740 


47 


0.9399 


72 


0.8850 


97 


0.8084 


23 


0.9729 


48 


0.9381 


73 


0.8825 


98 


0.8041 


24 


0.9719 


49 


0.9362 


74 


0.8799 


99 


0.7995 


25 


0.9709 


50 


0.9343 


75 


0.8773 


100 


0.7946 



28 



434 APPENDIX. 

TABLE III. Proportion between per cent, by weight and, by 

volume of alcoholic fluids at 59 F. 

(According to Starapfer.) 



100 liters of 
the alcoholic 
liquid 
contain 


Density or 
specific gravity 
of the fluid. 


00 

rC 

1|| ( 

o 


In 100 
kilgr. 


In 

1 hi. 


100 liters of 
he alcoholic 
liquid 
contain 


cfi ~ 

ft * 


Ji- 


In 100 
kilgr. 


In 
1 hi. 


3f the alcoholic 
liquid 
are contained 
alcohol, kilogr. 


^J T3 S 

"o '5 2 Of the alcoholic 
liqiid 
JsJ-^ ' are contained 
rH^'" alcohol, kilogr. 


Alco- 
hol, 
liters. 


Water, 
liters. 


Alco- 
hol, 

iters 


Water, 
liters. 


100 


0.00 


.7951 


79.51 100.00 


79.51 


49 


54.70 


.9366 


93.66 


41.59 


38.96 


99 


1.28 


.8000 


80.00 


98.38 


78.71 


48 


55.68 


9385 


93.85 


40.66 


38.16 


98 


2.54 


8046 


80.46 


96.83 


77.92 


47 


56.66 


9403 


94.03 


39.74 


37.37 


97 


3.77 


8089 


80.89 


95.35 


77.12 


46 


57.64 


9421 


94.21 


38.82 


36.57 


96 


4.97 


8130 


81.30 


93.89 


76.33 


45 


58.61 


9439 


94.39 


37.90 


35.78 


95 


6.16 


8169 


81.69 


92.45 


75.53 


44 


59.58 


9456 


9456 


37. 


34.98 


94 


7.32 


8206 


82.06 


91.08 


74.74 


43 


60.54 


9473 


94.73 


36.09 


34.19 


93 


8.48 


8242 


82.42 


89.72 


73.94 


42 


61.50 


9490 


94.90 


35.18 


33.39 


92 


9.62 


8277 


82.77 


88.37 


73.15 


41 


62.46 


9506 


95.06 


34.30 


32.60 


91 


10.76 


8311 


83.11 


87.04 


72.35 


40 


63.42 


).9522 


95.22 


33.40 


31.80 


90 


11.88 


.8344 


83.44 


85.74 


71.56 


39 


64.37 


9538 


95.38 


32.52 


31.01 


89 


13.01 


8377 


83.77 


84.74 


70.76 


38 


65.32 


9553 


95.53 


31.63 


30.21 


88 


14.12 


8409 


84.09 


83.22 


69.97 


37 


66.26 


95(58 


95.68 \ 


30.75 


29.42 


87 


15.23 


8440 


84.40 


81.96 


69.17 


36 


67.20 


9582 


95.82 


29.88 


28.62 


86 


16.32 


8470 


84.70 


80.72 


68.38 


35 


68.12 


9595 


95.95 


29.01 


27.83 


85 


17.42 


8500 


85.00 


79.51 


67.58 


34 


69.04 


9607 


96.07 


28.14 


27.03 


84 


18.52 


8530 


85.30 


78.29 


66.78 


33 


69.96 


9620 


96.20 


27.27 


26.24 


83 


19.61 


8559 


85.59 


77.09 


65.99 


32 


70.89 


9633 


96.33 


26.41 


25.44 


82 


20.68 


8588 


85.88 


75.91 


65.10 


31 


71.80 


9645 


96.45 


25.56 


24.65 


81 


21.76 


8616 


86.16 


74.75 


64.40 


30 


72.72 


0.9657 


96.57 


24.70 


23.85 


80 


22.83 


0.8644 


86.44 


73.59 


63.67 


29 


73.62 


9668 


96.68 


23.85 


23.06 


79 


23.90 


8671 


86.71 


72.43 


62.81 


28 


74.53 


9679 


96.79 


23. 


22.26 


78 


24.96 


8698 


86.98 


71.30 


62.02 


27 


75.43 


9690 


96.90 


22.16 


21.47 


77 


26.03 


8725 


87.25 


70.16 


61.22 


26 


76.33 


9701 


97.01 


21.31 


20.67 


76 


27.09 


8752 


87.52 


69.04 


60.43 


25 


77.23 


9711 


97.11 


20.47 


19.88 


75 


28.15 


8778 


87.78 


67.93 


59.63 


24 


78.13 


9721 


97.21 


19.63 


19.08 


74 


29.20 


8804 


88.04 


66.82 


58.84 


23 


79.02 


9731 


97.31 


18.79 


18.29 


73 


30.26 


8830 


88.30 


65.72 


58.04 


22 


79.9: 


9741 


97.41 


17.96 


17.49 


72 


31.30 


8855 


88.55 


64.64 


57.25 


21 


80.81 


9751 


97.51 


17.12 


16.70 


71 


32.35 


8880 


88.80 


63.68 


56.45 


20 


81.71 


0.9761 


97.61 


16.29 


15.90 


70 


33.39 


0.8905 


89.05 


62.50 


55.66 


19 


82.60 


9771 


97.71 


15.46 


15.11 


69 


34.44 


8930 


89.30 


61.43 


54.86 


18 


83.50 


9781 


97.81 


14.63 


14.31 


68 


35.47 


8954 


89.54 


60.38 


54.07 


17 


84.39 


9791 


97.91 


13.80 


13.52 


67 


36.51 


8978 


89.78 


59.33 


53.27 


16 


85.29 


9801 


98.01 


12.98 


12.72 


66 


37.54 


9002 


90.02 


58.29 52.48 


15 


86.19 


9812 


98.12 


12.15 


11.93 


65 


38.58 


9026 


90.26 


57.25 


51.68 


14 


87.09 


9822 


98.22 


11.33 


11.13 


64 


39.60 


9049 


90.49 


56.23 


50.89 


13 


88. 


9833 


98.33 


10.51 


10.34 


63 


40.63 


9072 


90.72 


55.21 


50.09 


12 


88.90 


9844 


98.44 


9.69 


9.54 


62 


41.65 


9095 


90.95 


54.20 


49.30 


11 


89.80 


9855 


98.55 


8.78 


8.75 


61 


42.67 


9117 


91.17 


53.19 


48.50 


10 


90.7 


0.9867 


98.67 


8.06 


7.95 


60 


43.68 


0.9139 


91.39 


52.20 


47.71 


9 


91.62 


9878 


98.78 


7.24 


7.16 


59 


44.70 


9161 


91.61 


51 .20 


46.92 


8 


92.54 


9890 


98.90 


6.43 


6.36 


58 


45.72 


9183 


91.83 


50.21 


46.12 


7 


93.4 


9902 


99.02 


5.62 


5.57 


57 


46.73 


9205 


92.05 


49.24 


45.32 


6 


94.3 


9915 


99.15 


4.81 


4.77 


56 


47.73 


9226 


92.26 


48.26 


44.53 


5 


95.3 


9928 


99.28 


4. 


3.98 


55 


48.74 


9247 


92.47 


47.40 


43.73 


4 


96.2 


9942 


99.42 


3.20 


3.18 


54 


49.74 


9267 


92.67 


46.33 


42.94 


3 


97.7 


9956 


99.56 


2.40 


2.39 


53 


50.74 


9288 


92.88 


45.37 


42.14 


2 


98.1 


9970 


99.70 


1.60 


1.59 


52 


51.74 


9308 


93.08 


44.41 


41.35 


1 


99.0 


9985 


99.85 


0.80 


0.80 


51 


52.73 


9328 


93.28 


43.47 


40.55 





100.0 


1.0000 


100.00 


0.00 


0.00' 


50 


53.72 


0.9348 


93.48 


42.53 


39.76 















APPENDIX. 



435 



TABLE IV. The actual content of alcohol and water in mixtures 
of both fluids, and the contraction which takes place in mixing. 



Specific 
gravity. 


100 volumes contain 
volumes 


Contrac- 
tion. 


Specific 
gravity. 


100 volumes contain 
volumes 


Contrac- 
tion. 


Alcohol. 


Water. 


Alcohol. Water. 


1.0000 





100.000 


0.000 


0.9323 


51 


52.705 


0.705 


0.9985 


1 


99.055 


055 


03 


52 


51.711 


711 


70 


2 


98.111 


111 


0.9283 


53 


50.716 


716 


56 


3 


97.176 


176 


63 


54 


49.722 


722 


42 


4 


96.242 


242 


42 


55 


48.717 


717 


28 


5 


95.307 


307 


21 


56 


47.712 


712 


15 


6 


94.382 


382 


0.9200 


57 


46.708 


708 


02 


7 


93.458 


458 


0.9178 


58 


45.693 


693 


0.9890 


8 


92.543 


543 


56 


59 


44.678 


678 


78 


9 


91.629 


629 


34 


60 


43.664 


664 


66 


10 


90.714 


714 


12 


61 


42.649 


649 


54 


11 


89.799 


799 


0.9090 


62 


41.635 


635 


83 


12 


88.895 


895 


67 


63 


40.610 


610 


32 


13 


87.990 


990 


44 


64 


39.586 


586 


21 


14 


87.086 


1.086 


21 


65 


38.561 


561 


11 


15 


86.191 


191 


0.8997 


66 


37.526 


526 


0.9SOO 


16 


85.286 


286 


73 


67 


36.492 


492 


0.9790 


17 


84.392 


392 


49 


68 


35.457 


457 


80 


18 


83.497 


497 


25 


69 


34.423 


423 


70 


19 


82.603 


603 


0.8900 


70 


33.378 


378 


60 


20 


81.708 


708 


75 


71 


32.333 


333 


50 


21 


80.813 


813 


50 


72 


31.289 


289 


40 


22 


79.919 


919 


25 


73 


30.244 


244 


29 


23 


79.014 


2.014 


0.8799 


74 


29.190 


190 


19 


24 


78.119 


119 


73 


75 


28.135 


135 


09 


25 


77.225 


225 


47 


76 


27.080 


080 


0.9698 


26 


76.320 


320 


20 


77 


26.016 


016 


88 


27 


75.426 


426 


0.8693 


78 


24.951 


2.951 


77 


28 


74.521 


521 


65 


79 


23.877 


877 


66 


29 


73.617 


617 


39 


80 


22.822 


822 


55 


30 


72.712 


712 


11 


81 


21.747 


747 


43 


31 


71.797 


797 


0.8583 


82 


20.673 


673 


31 


32 


70.883 


883 


55 


83 


19.598 


598 


18 


33 


69.958 


958 


26 


84 


18.514 


514 


05 


34 


69.034 


3.034 


0.8496 


85 


17.419 


419 


0.9592 


35 


68.109 


109 


66 


86 


16.324 


324 


79 


36 


67.184 


184 


36 


87 


15.230 


230 


65 


37 


66.250 


250 


05 


88 


14.125 


125 


50 


38 


65.305 


305 


0.8373 


89 


13.011 


Oil 


35 


39 


64.361 


361 


39 


90 


11.876 


1.876 


19 


40 


63.406 


406 


06 


91 


10.751 


751 


03 


41 


62.451 


451 


0.8272 


92 


9.617 


617 


0.9487 


42 


61.497 


497 


37 


93 


8.472 


472 


70 


43 


60.532 


532 


01 


94 


7.318 


318 


52 


44 


59.558 


558 


0.8764 


95 


6.153 


153 


35 


45 


58.593 


593 


25 


96 


4.968 


0.968 


17 


46 


57.618 


618 


0.8084 


97 


3.764 


764 


0.9399 


47 


56.644 


644 


41 


98 


2.539 


539 


81 


48 


55.669 


669 


0.7995 


99 


1.285 


285 


62 


49 


54.685 


685 


46 


100 


0.000 


000 


43 


50 


53.700 


700 











436 



APPENDIX. 



TABLE Y. For comparing the different areometers with 

Tralles's alcoholometer. 

The statements of figures of the other areometers corresponding to the per 
cent, by volume according to Tralles's alcoholometer stand in the same 
horizontal line. 



Per cent, by 
volume accord- 
ing to Tralles. 


Per cent, by 
weight. 


Areometer of 


Per cent, by 
volume accord- 
ing to Tralles. 


Per cent, by 
weight. 


Areometer of 


Richter. 


i 

<s 
PQ 


Beaume. 


Cartier. 


Richter. 


M 

V 
<D 

PQ 


Beaume. 


Cartier. 


o 


0. 


0.0 


0.0 


10 


11 


51 


43.47 





12.3 








I 


0.80 














52 


44.42 





12.7 








2 


1.60 














53 


45.36 





13.1 


21 





3 


2.40 














54 


46.32 





13.5 





21 


4. 


3.20 





1.0 








55 


47.29 


41.00 


13.9 








5 


4.10 


4.00 


1.2 


11 


12 


56 


48.26 





14.3 


22 





6 


4.81 





1.4 








57 


49.23 





14.8 





22 


7 


5.62 





1.6 








58 


50.21 





15.2 


23 





8 


6.43 





1.9 








59 


51.20 





15.6 








9 


7.24 





2.1 








60 


52.20 


45.95 


16.1 





23 


10 


8.05 


7.50 


2.3 


12 





61 


53.20 





16.5 


24 





11 


8.87 





2.5 








62 


54.21 





17.0 








12 


9.69 





2^7 





13 


63 


55.21 





17.5 


25 


24 


13 


10.51 





2.9 








64 


56.22 





18.0 








14 


11.38 





3.1 








65 


57.24 


51.40 


18.4 





25 


15 


12.15 


10.58 


3.3 








66 


58.27 





18.9 


26 





16 


12.98 





3.5 


13 





67 


59.32 





19.4 








17 


13.80 





3.6 







68 


60.38 





20.0 


27 


26 


18 


14.63 





3.8 








69 


61.42 





20.5 








19 


15.46 





4.0 





14 


70 


62.50 


57.12 


21.0 


28 


27 


20 


16.28 


13.55 


4.2 








71 


63.58 





21.5 








21 


17.11 





4^4 





_^ 


72 


64.66 





22.1 








22 


17.95 





4.6 








73 


65.74 





22.6 


29 


28 


23 


18.78 





4.8 


14 





74 


66.83 





23.2 








24 


19.62 





4.9 








75 


67.93 


62.97 


23.8 


30 


29 


25 


20.46 


16.60 


5.1 








76 


69.05 





24.4 








26 


21.30 





5.3 





15 


77 


70.18 





25.0 


31 


30 


27 


22.14 





5.6 








78 


71.31 





25.6 








28 


22.96 





5.7 








79 


72.45 





26.2 


32 





29 


23.84 





59 


15 





80 


73.59 


69.20 


26.8 





31 


30 


24.69 


19.78 


6.1 








81 


74.74 





27.4 


33 





31 


25.55 





6.4 








82 


75.91 





28.0 


34 


32 


32 


26.41 





6.6 








83 


77.09 





28.7 








33 


27.27 





6.8 





16 


84 


78.29 





29.4 


35 


33 


34 


28.13 





7.0 


16 





85 


79.50 


75.35 


30.1 








35 


28.99 


23.50 


7.2 







86 


80.71 





30.8 


36 


34 


36 


29.86 





7.5 








87 


81.94 





31.5 


37 


35 


37 


30.74 


25.50 


7.7 








88 


83.19 





32.2 








38 


31.62 





8.0 





17 


89 


84.46 





33.0 


38 


36 


39 


32.50 





8.3 


17 





90 


85.75 


81.86 


33.8 








40 


33.39 


27.95 


8.6 








91 


87.05 





34.7 


39 


37 


41 


34.28 





8.9 








92 


88.37 





35.5 


40 


38 


42 


35.18 





9.2 





18 


93 


89.71 





36.4 


41 





43 


36.08 





9.5 


18 





94 


91.07 





37.3 





39 


44 


36.99 





9.8 








95 


92.46 


89.34 


38.2 


42 


40 


45 


37.90 


28.30 


10.2 








96 


93.89 





39.2 


43 





46 


38.82 





10.5 


19 


19 


97 


95.34 





40.3 


44 


41 


47 


39.74 





10.9 








98 


96.84 





41.5 


45 


42 


48 


40.61 





11.2 








99 


98.39 





42.7 


46 


43 


49 


41.59 





11.6 








100 


100.00 


100.00 


43.9 


47 





50 


42.52 


36.46 


11.9 


20 


20 















APPENDIX. 437 



Determination of the true strengths of spirit for the normal 
temperature of 59 F. 

When for the determination of the strength of a spirit of wine 
the stand of the alcoholometer and of the thermometer has been 
read off, we possess two figures, by means of which the true 
strength of spirit of the spirits of wine to be examined, i. e., the 
number of liters of absolute alcohol contained in 100 liters of the 
fluid to be examined, when the latter possesses a normal temperature 
of 59 F., is found as follows: If the observed temperature of the 
fluid is = 59 F., which is indicated on the scale of the thermo- 
meter with a red mark, the figure read off on the scale of the 
alcoholometer indicates at once the " true" strength of spirit. If, 
however, the thermometer shows a different temperature, in which 
case the figure read off on the scale of the alcoholometer is termed 
the "apparent" strength of spirit, the true strength of spirit is 
found from the figure read off on the scale of the alcoholometer 
and the temperature with the assistance of the following table : 

Table VI. has two entries ; one in the uppermost horizontal line 
for the observed statements of the alcoholometer, hence the appa- 
rent strengths from 31 to 44 per cent. ; the other in the first vertical 
column for the statements of Fahrenheit's thermometer from 13 
to +99.5. On the place where a vertical and horizontal column 
cross, the strength corresponding to the normal temperature of 
59 F., i. e., the true strength of spirit is found. 

If, for instance, the alcoholometer immersed into a sample of 
spirits of wine, indicates an apparent strength of 77 per cent., and 
the thermometer the temperature of the fluid as 25.5 F., the figure 
77 has to be found in the uppermost horizontal column, and then 
the vertical column belonging to it is followed downward until the 
horizontal line is reached in which stands the figure 25.5 in the 
column containing the degrees of temperature. Here the statement 
82.4 will be found as the true strength of spirit, and this figure 
indicates that at the normal temperature of 59 F. 100 liters of the 
spirit of wine examined contain 82.4 liters of absolute alcohol. 

When the apparent strength read off on the alcoholometer con- 
sists of a whole number and a fraction, the true strength corre- 
sponding to the whole number is determined in the above manner, 
and the surplus fraction added to the number found. 



438 APPENDIX. 

If, for instance, the temperature read off is 74.75, and the appa- 
rent strength 81 f per cent., the true strength belonging to 81 per 
cent, and 74.75, which is = 78.4, is first found in the table and to 
this is added the fraction f = 0.75 or sufficiently accurate = 0.7. 
This gives 78.4 + 0.7 = 79.1 per cent, as the nearest accurate true 
strength. 



APPENDIX. 



439 



TABLE YI. Determination of the true strengths of spirit for the 
normal temperature of 59 F. (15 C.). 



Tempera- 
ture, 
degrees C. 


Tempera- 
ture, 
degrees F. 


31 


32 


33 


34 


35 36 


37 


38 


30 


40 


41 


True strengths of spirit for the above apparent strengths. 


25 


13 


47.9 


48.7 


49.5 


50.3 


51.1 51.9 


52.7 


53.6 


54.4 55.2 


56.0 


23.75 


10.75 


47.4 


48.2 


49.0 


49.8 


50.6 ' 51.5 


52.3 


53.1 


53.9 54.7 


55.5 


22.5 


8.5 


46.9 


47.7 


48.5 


49.3 


50.1 i 51.0 


51.8 


52.6 


53.4 54.3 


55.1 


21.25 


6.25 


46.4 


47.2 


48.0 


48.8 


49.6 50.5 


51.3 


52.1 


53.0 53.8 


54.6 


20 4 


45.8 


46.7 


47.5! 


48.3 


49.2 


50.0 


50.8 


51.7 


52.5 53.3 


54.2 


18.75 


1.75 


45.3 


46.1 


47.0 


47.8 


48.7 


49.5 


50.3 


51.2 


52.0 52.9 


53.7 


17.5 


+0.5 


44.8 


45.6 


46.5 


47.3 


48.2 


49.0 


49.9 


50.7 


51.6 52.4 


53.3 


16.25 


+2.75 


44.2 


45.1 


46.0 


46.8 


47.7 


48.5 


49.4 


50.2 


51.1 51.9 


52.8 


15 


+ 5 


43.7 


44.6 


45.4 


46.3 


47.2 


48.0 


48.9 


49.7 


50.6 i 51.5 


52.3 


13.75 


+ 7.25 


43.2 


44.1 


44.9 


45.8 


46.7 S47.5 


48.4 


49.3 


50.1 i 51.0 


51.9 


12.5 


+ 9.5 


42.7 


43.5 


44.4 


45.3 


46.2 47.1 


47.9 


48.8 


49.7 50.6 


51.4 


11.25 


+ 11.75 


42.1 


43.0 


43.9 


44.8 


45.7 I 46.6 


47.5 


48.3 


49.2 50.1 


51.0 


10 


+ 14 


41.6 


42.5 


43.4 


44.3 


45.2 ! 46.1 


47 


47.9 


48.8 49.7 


50.6 


8.75 j +16.25 


41.1 


42.0 


42.9 


43.8 


44.7 ! 45.6 


46.5 


47.4 


48.3 49.2 


50.1 


7.5 


+ 18.5 


40.6 


41.5 


42.4 


43.3 


44.2 45.1 


46.0 


46.9 


47.9 48.8 


49.7 


6 


+ 20.75 


40.1 


41.0 


41.9 


42.8 


43.7 44.6 


45.6 


46.5 


47.4 48.3 


49.2 


5 


+23 


39.5 


40.5 


41.4 


42.3 


43.2 44 2 


45.1 


46.0 


46.9 47.8 


48.8 


3.75 


+25.25 


39.0 


39.9 


40.9 


41.8 


42.7 43.7 


44.6 


45.5 


46.4 47.4 


48.3 


2.5 


+27.5 


38.4 


39.4 


40.3 


41.3 


42.2 43.2 


44.1 


45.0 


45.9 46.9 


47.8 


1.25 


+29.75 


37.9 


38.9 


39.8 


40.8 


41.7 42.7 


43.6 


44.5 


45.5 46.4 


47.3 





+32 


37.4 


38.3 


39.3 


40.3 


41.2 


42.2 


43.1 


44.0 


45.0 


45.9 


46.9 


+1.25 


+ 34.25 


36.8 


37.8 


38.8 


39.7 


40.7 


41.7 


42.6 


43.5 


44.5 


45.4 


46.4 


4-2.5 1+36.5 


36.3 


37.3 


38.2 


39.2 


40.2 


41.1 


42.1 


43.0 


44.0 


45.0 


45.9 


+3.75+38.75 


35.7 


36.7 


37.7 


i 38.7 


39.7 


40.6 


41.6 


42.5 


43.5 


44.5 


45.4 


+ 5 ] +41 


35.2 


36.2 


37.2 


i 38.2 


39.1 


40.1 


41.1 


42.0 


43.0 


44.0 


44.9 


+6.25 +43 


34.7 


35.7 


36.7 


37.6 


38.6 


39.6 


40.6 


41.5 


42.5 


43.5 


44.5 


+ 7.5 i +45.5 


34.1 


35.1 


36.1 


37.1 


38.1 


39.1 


40.1 


41.0 


42.0 


43.0 


44.0 


+8.75 +47.75 


33.6 


34.6 


35.6 


36.6 


37.6 


38.6 


39.6 


40.5 


41.5 


42.5 


43.5 


+10 +50 


33.1 


34.1 


35.1 


36.1 


37.1 


38.1 


39.0 


40.0 


41.0 


42.0 


43.0 


+11.25 +52.25 


32.5 


33.6 


34.6 


35.6 


36.6 


37.5 


38.5 


39.5 


40.5 


41.5 


42.5 


+12.5 


+54.5 


32.0 


33.0 


34.0 


35.0 


36.0 


37.0 


38.0 


39.0 


40.0 


41.0 


42.0 


+13.75 


+ 56.75 


31.5 


32.5 I 33.5 


34.5 


35.5 


36.5 


37.5 


38.5 


39.5 


40.5 41.5 


+ 15 


+59 


31.0 


32.0 33.0 


34.0 


35.0 


36.0 


37.0 


38.0 


39.0 


40.0 41.0 


+16.25 


+ 61.25 


30.5 


31.5 


32.5 


33.5 


34.5 


35.5 


36.5 


37.5 


38.5 


39.5 40.5 


+ 17.5 


+ 63.5 


30.0 


31.0 


32.0 


33.0 


34.0 


35.0 


36.0 


37.0 


38.0 


39.0 40.0 


+ 18.75 


+ 65.75 


29.5 


30.5 


31.5 


32.5 


33.5 


34.5 


35.5 


36.5 


37.5 


38.5 39.5 


+20 


+ 68 


29.0 


30.0 


31.0 


31.9 


32.9 


33.9 


35.0 


36.0 


37.0 


38.0 39.0 


+21.25 


+ 70.25 


28.5 


29.5 


30.4 


31.4 


32.4 


33.4 


34.4 


35.5 


36.5 


37.5 38.5 


+22.5 


+ 72.5 


28.0 


29.0 


29.9 


i 30.9 


31.9 


32.9 


33.9 


34.9 


36.0 


37.0 38.0 


+23.75 


+ 74.75 


27.5 


28.5 


29.4 


30.4 


31.4 


32.4 


33.4 


34.5 


35.5 


36.5 : 37.5 


+25 


+77 


27.0 


28.0 


28.9 


29.9 


30.9 


31.9 


32.9 


33.9 


84.9 


36.0 i 37.0 


+26.25 


+ 79.25 


26.5 


27.5 


28.4 


29.4 


30.4 


31.4 


32.4 


33.4 


34.4 


35.5 i 36.5 


+27.5 


+ 81.5 


26.0 


27.0 


28.0 


i28.9 


29.9 


30.9 


31.9 


32.9 


33.9 


35.0 36.0 


+28.75 


+ 83.75 


25.6 


26.5 


27.5 


28.4 


29.4 


30.4 


31.4 


32.4 


33.4 


34.4 35.5 


+30 


+86 


25.1 


26.0 


27.0 


27.9 


28.9 


29.9 


30.9 


31.9 


32 9 


33.9 i 35.0 


+31.25 


+ 88.25 


24.6 


25.5 


26.5 


J27.4 


28.4 


29.4 


30.4 


31.4 


32.4 


33.4 i 34.5 


+32.5 


+90.5 


24.1 


25.0 


26.0 


26.9 


27.9 


28.9 


29.9 


30.9 


31.9 


32.9 34.0 


+33.75 


+92.75 


23.6 


24.5 


25.5 


26.4 


27.4 


28.4 


29.4 


30.4 


31.4 


32.4 33.5 


+ 35 


+95 


23.1 


24.1 


25.0 


25.9 


26.9 


27.9 


28.9 


29.9 


30.9 


31.9 | 32.9 


+36.25 


+97.25 


22.7 


23.6 


24.5 


25.4 


26.4 


27.4 


28.4 


29.4 


30.4 


31.4 32.4 


+37.5 


+99.5 


22.2 


23.1 


24.0 , 24.9 


25.9 


26.9 


27.9 


28.9 


29.9 


30.9 31.9 



440 



APPENDIX. 



TABLE VI. (continued.) 



Tempera- 
ture, 
degrees C. 


Tempera- 
ture, 
degrees F. 


42 


43 


44 


45 


46 


47 


48 


49 


50 


51 


52 


True strengths of spirit for the above apparent strengths. 


25 


13 


56.8 


57.6 


58.4 


59.3 


60.1 


61.0 


61.8 


62.7 


63.6 


64.5 


65.4 


23.75 


10.75 


56.3 


57.2 


58.0 


58.8 


59.7 


60.6 


61.4 


62.3 


63.2 


64.1 


65.0 


22.5 




-8.5 


55.9 


56.7 


57.6 


58.4 


59.3 


60.1 


61.0 


61.9 


62.8 


63.7 


64.6 


21.25 


6.25 


55.4 


56.3 


57.1 


58.0 


58.8 


59.7 


60.6 


61.5 


62.4 


63.3 


64.2 


20 


_ 


-4 


55.0 


55.8 


56.7 


57.6 


58.4 


59.3 


60.2 


61.1 


61.9 


62.9 


63.8 


18.75 


1.75 


54.6 


55.4 


56.3 


57.1 


58.0 


58.9 


59.7 


60.6 


61.5 


62.5 


63.4 


17.5 




-0.5 


54.1 


55.0 


55.8 


56.7 


57.6 


58.4 


59.3 


60.2 


61.1 


62.1 


63.0 


16.25 




-2.75 


53.7 


54.5 


55.4 


56.3 


57.1 


58.0 


58.9 


59.8 


60.7 


61.7 


62.6 


15 




-5 


53.2 


54.1 


55.0 


55.8 


56.7 


57.6 


58.5 


59.4 


60.3 


61.2 


62.2 


13.75 




-7.25 


52.8 


53.6 


54.5 


55.4 


56.3 


57.2 


58.1 


59.0 


59.9 


60.8 


61.8 


12.5 




-9.5 


52.3 


53.2 


54.1 


55.0 


55.9 


56.8 57.7 


58.6 


59.5 


60.4 


61.4 


11.25 


+11.75 


51.9 


52.8 


53.7 


54.5 


55.4 


56.3 


57.2 


58.2 


59.1 


60.0 


61.0 


10 


+ 14 


51.4 


52.3 


53.2 


54.1 


55.0 


55.9 


56.8 


57.8 


58.7 


59.6 


60.6 


8.75 


+16.25 


51.0 


51,9 


52.8 


53.7 


54.6 


55.5 


56.4 


57.3 


58.3 


59.2 


60.2 


7.5 


+18.5 


50.6 


51.5 


52.4 


53.3 


54.2 


55.1 


56.0 


56.9 


57.9 


58.8 


59.8 


6 


+20.75 


50.1 


51.0 


51.9 


52.9 


53.8 


54.7 


55.6 


56.5 


57.5 


58.4 


59.3 


5 


+ 23 


49.7 


50.6 


51.5 


52.4 


53.3 


54.3 


55.2 


56.1 


57.0 


58.0 


58.9 


3.75 


+ 25.25 


49.2 50.1 


51.1 


52.0 


52.9 


53.8 


54.8 


55.7 


56.6 


57.6 


58.5 


2.5 


+27.5 


48.8,49.7 


50.6 


51.6 


52.5 


53.4 


54.3 


55.3 


56.2 


57.2 


58.1 


1.25 


+29.75 


48.3 49.2 


50.2 


51.1 


52.0 


53.0 


53.9 


54.9 


55.8 


56.8 


57.7 





+32 


47.8 


48.8 


49.7 


50.7 


51.6 


52.5 


53.5 


54.4 


55.4 


56.3 


57.3 


+1.25 


+34.25 


47.4 


48.3 


49.3 


50.2 


51.2 


52.1 


53.0 


54.0 


54.9 


55.9 


56.9 


+ 2.5 


+36.5 


46.9 


47.8 


48.8 


49.8 


50.7 


51.6 


52.6 


53.5 


54.5 


55.5 


56.4 


4-3.75 


+38.75 


46.4 


47.4 


48.3 


49.3 


50.2 


51.2 


52.1 


53.1 


54.1 


55.0 


56.0 


+ 5 


4-41 


45.9 


46.9 


47.9 


48.8 


49.8 


50.7 


51.7 


52.7 


53.6 


54.6 


55.6 


+6.25 


+43 


45.4 


46.4 


47.4 


48.3 


49.3 


50.3 


51.2 


52.2 


53.2 


54.2 


55.1 


4-7.5 


+45.5 


44.9 


45.9 


46.9 


47.9 


48.8 


49.8 


50.8 


51.8 


52.7 


53.7 


54.7 


+ 8.75 


+47.75 


44.5 


45.4 


46.4 


47.4 


48.4 


49.4 


50.3 


51.3 


52.3 


53.3 


54.2 


+10 


+ 50 


44.0 


44.9 


45.9 


46.9 


47.9 


48.9 


49.9 


50.9 


51.8 


52.8 


53.8 


+ 11.25 


+ 52.25 


43.5 


44.5 


45.5 


46.4 


47.4 


48.4 


49.4 


50.4 


51.4 


52.4 


53.4 


+ 12.5 


+ 54.5 


43.0 


44.0 


45.0 


46.0 


47.0 


48.0 


48.9 


49.9 


50.9 


51.9 


52.9 


+ 13.75 


+ 56.75 


42.5 


43.5 


44.5 


45.5 


46.5 


47.5 


48.5 


49.5 


50.5 


51.5 


52.5 


+15 


+59 


42.0 


43.0 


44.0 


45.0 


46.0 


47.0 


48.0 


49.0 


50.0 


51.0 


52.0 


+ 16.25 


+61.25 


41.5 


42.5 


43.5 


44.5 


45.5 


46.4 


47.5 


48.5 


49.5 


50.5 


51.5 


+17.5 


+ 63.5 


41.0 


42.0 


43.0 


44.0 


45.0 


46.0 


47.1 


48.1 


49.1 


50.1 


51.1 


+18.75 


+ 65.75 


40.5 


41.5 


42.5 


43.5 


44.5 


45.6 


46.6 


47.6 


48.6 


49.6 


50.6 


+20 


+ 68 


40.0 


41.0 


42.0 


43.1 


44.1 


45.1 


46.1 


47.1 


48.1 


49.1 


50.2 


+21.25 


+ 70.25 


39.5 


40.5 


41.6 


42.6 


43.6 


44.6 


45.6 


46.6 


47.6 


48.7 


49.7 


+22.5 


+72.5 


39.0 


40.0 


41.1 


42.1 


43.1 


44.1 


45.1 


46.1 


47.2 


48.2 


49.2 


+23.75 


+ 74.75 


38.5 


39.5 


40.6 


41.6 


42.6 


43.6 


44.6 


45.7 


46.7 


47.7 


48.7 


+25 


+77 


38.0 


39.0 


40.1 


41.1 


42.1 


43.1 


44.2 


45.2 


46.2 


47.2 


48.3 


+26.25 


+ 79.25 


37.5 


38.5 


39.6 


40.6 


41.6 


42.6 


43.7 


44.7 


45.7 


46.8 


47.8 


+27.5 


+ 81.5 


37.0 


38.0 


39.1 


40.1 


41.1 


42.2 


43.2 


44.2 


45.2 


46.3 


47.3 


+28.75 


+ 83.75 


36.5 


37.5 


38.6 


39.6 


40.6 


41.7 


42.7 


43.7 


44.8 


45.8 


46.8 


+ 30 


+ 86 


36.0 


37.0 


38.1 


39.1 


40.1 


41.2 


42.2 


43.2 


44.3 


45.3 


46.4 


+31.25 


+ 88.25 


35.5 


36.5 


37.6 


38.6 


39.6 


40.7 


41.7 


42.7 


43.8 


44.8 


45.9 


+32.5 


+90.5 


35.0 


36.0 


37.1 


38.1 


39.1 


40.2 


41.2 


42.3 


43.3 


44.4 


45.4 


+33.75 


+92.75 


34.5 


35.5 


36.6 


37.6 


38.6 


39.7 


40.7 


41.8 


42.8 


43.9 


44.9 


+35 


+95 


34.0 


35.0 


36.1 


37.1 


38.1 


39.2 


40.2 


41.3 


42.3 


43.4 


44.4 


+36.25 


+ 97.25 


33.5 


34.5 


35.6 


36.6 


37.6 


38.7 


39.7 


40.8 


41.8 


42.9 


43.9 


+37.5 


+99.5 


33.0 


34.0 


35.1 


36.1 


37.1 


38.2 


39.2 


40.3 


41.3 


42.4 


43.4 



APPENDIX. 



441 



TABLE VI. (continued.) 



ture, 
degrees C. 


Tempera- 
ture, 
degrees F. 


53 


54: 


55 


56 57 


58 


59 


60 


61 


62 


63 


True strengths of spirit for the ahove apparent strengths. 


25 


13 


66.3 


67.2 68.1 


69.1 


70.0 


70.9 


71.8 


72.7 7:',.i; 


74.4 


75.3 


23.75 


10.75 


65.9 


66 8 67.7 


68.7 


69.6 


70.5 


71.4 


72.3 


73.2 


74.1 


75.0 


22.5 


8.5 


65.5 


66.4 67.3 


68.3 


69.2 70.1 


71.0 


71.9 72.8 73.7 


74.6 


21.25 


6.25 


65.1 


66.0 


67.0 


67.9 


68.8 


69.7 


70.6 


71.5 


72.4 73.3 


74.2 


20 


4 


64.7 


65.6 


66.6 


67.5 


68.4 


69.3 


70.2 


71.1 72.0 72.9 


73.9 


18.75 


1.75 


64.3 


65.2 


66.2 


67.1 


68.0 


68.9 


69.8 


70.8 71.7 72.6 


73.5 


17.5 


4-0.5 


63.9 


64.8 


65.8 


66.7 


67.6 


68.5 


69.5 


70.4 1 71.3 72.2 


73.1 


16.25 


4-2.75 


63.5 


64.4 


65.4 


66.3 


67.2 


68.1 


69.1 


70.0 70.9 


71.8 


72.7 


15 


+5 


63.1 


64.0 


65.0 


65.9 


66.8 


67.8 


68.7 


89.6 


70.5 


71.4 


72.4 


13.75 


4-7.25 


62.7 


63.6 


64.6 


65.5 


66.4 


67.4 


68.3 


69.2 70.2 


71.1 


72.0 


12.5 


+ 9.5 


62.3 


63.2 


64.2 


65.1 66.0 


67.0 


67.9 


68.9 ! 69.8 


70.7 


71.6 


11.25 


+11.75 


61.9 


62.8 


63.8 


64.7 65.7 


66.6 


67.6 


68.5 69.4 


70.3 71.3 


10 


+ 14 


61.5 


62.4 


63.4 


64.3 65.3 


66.2 


67.2 


68.1 69.0 


70.0 70.9 


-8.75 


+ 16.25 


61.1 


62.0 


63.0 


63.9 64.9 


65.9 


66.8 


67.7 ! 68.7 


69.6 70.5 


-7.5 


+ 18.5 


60.7 


61.6 62.6 


63.6 ! 64.5 


65.5 


66.4 


67.4 1 68.3 


69.2 


70.2 


-6 


+20.75 


60.3 


61.2 j 62.2 


63.2 


64.1 


65.1 


66.0 


67.0 67.9 68.9 


69.8 


-5 


+ 23 


59.9 


60.8 61.8 


62.8 


63.7 


64.7 


65.6 


66.6 67.5 68.5 


69.4 


-3.75 


+25.25 


59.5 


60.4 


61.4 


62.4 


63.3 


64.3 


65.3 


66.2 


67.2 68.1 


69.1 


-2.5 


+27.5 


59.1 


60.0 


61.0 


62.0 


62.9 


63.9 64.9 


65.8 


66.8 67.7 


68.7 


-1.25 


4-29.75 


58.7 


59.6 


60.6 


61.6 


62.5 


63.5 


64.5 


65.4 


66.4 


67.3 


68.3 





+32 


58.3 


59.2 


60.2 


61.2 


62.1 


63.1 


64.1 


65.0 


66.0 


67.0 


67.9 


-1.25 


+ 34.25 


57.8 


58.8 


59.8 


60.7 


61.7 


62.7 


63.7 


64.6 


65.6 66.6 


67.5 


-2.5 +36.5 


57.4 


58.4 


59.3 


60.3 


61.3 


62.3 


63.3 


64.2 


65.2 ! 66.2 


67.1 


-3.75 4-38.75 


57.0 


57.9 


58.9 


59.9 


60.9 


61.9 


62.8 


63.8 


64.8 65.8 


66.7 


-5 4-41 


56.5 


57.5 


58.5 


59.5 


60.5 


61.4 


62.4 


63.4 


64.4 65.4 


66.3 


-6.25 4-43 


56.1 


57.1 


58.1 


59.0 


60.0 


61.0 


62.0 


63.0 


64.0 64.9 


65.9 


-7.5 4-45.5 


55.7 


56.6 


57.6 


58.6 


59.6 


60.6 


61.6 


62.6 


63.5 64.5 


65.5 


-8.75 4-47.75 


55.2 


56.2 


57.2 


58.2 


59.2 


60.2 


61.2 


62.1 


63.1 64.1 


65.1 


10 4-50 


54.8 


55.8 


56.8 


57.8 


58.7 


59.7 


60.7 


61.7 


62.7 63.7 


64.7 


11.25 -f-52.25 


54.3 


55.3 


56.3 


57.3 


58.3 


59.3 


60.3 


61.3 


62.3 63.3 


64.3 


12.5 1 4-54.5 


53.9 


54.9 


55.9 


56.9 


57.9 


58.9 


59.9 


60.9 


61. 9 ! 62.9 


63.9 


13.75 -4-56.75 


53.5 


54.4 


55.4 


56.4 


57.4 


58.4 


'59.4 


60.4 


61.4 ! 62.4 


63.4 


15 


+ 59 


53.0 


54.0 


55.0 


56.0 


57.0 


58.0 


59.0 


60.0 


61.0 62.0 


63.0 


16.25 


+61.25 


52.5 


53.5 


54.6 


55.6 


56.6 


57.6 


58.6 


59.6 


60.6 


61.6 


62.6 


17.5 


+ 63.5 


52.1 


53.1 


54.1 


55.1 


56.1 


57.1 


58.1 


59.1 


60.1 


61.1 


62.1 


18.75 


+ 65.75 


51.6 


52.6 


53.7 


54.7 


55.7 


56.7 


57.7 


58.7 


59.7 


60.7 


61.7 


20 


+68 


51.2 


52.2 


53.2 


54.2 


55.2 


56.2 


57.2 


58.3 


59.3 


60.3 


61.3 


21.25 


+ 70.25 


50.7 


51.7 


52.7 


53.8 


54.8 


55.8 


56.8 


57.8 


58.8 


59.8 


60.8 


22.5 


+ 72.5 


50.2 


51.3 


52.3 


53.3 


54.3 


55.3 


56.3 


57.4 


58.4 


59.4 


60.4 


23.75 


+74.75 


49.8 


50.8 


51.8 


52.8 


53.9 


54.9 


55.9 


56.9 


57.9 


58.9 


60.0 


25 


+77 


49.3 


50.3 


51.4 


52.4 


53.4 


54.4 


55.5 


56.5 


57.5 


58.5 


59.5 


26.25 


+ 79.25 


48.8 


49.9 


50.9 


51.9 


53.0 


54.0 55.0 


56.0 


57.0 


58.1 


59.1 


27.5 


+ 81.5 


48.4 


49.4 


50.4 


51.5 


52.5 


53.5 


54.5 


55.6 


56.6 


57.6 


58.6 


28.75 


+ 83.75 


47.9 


48.9 


50.0 


51.0 


52.0 


53.1 


54.1 


55.1 


56.1 


57.2 


58.2 


30 


+ 86 


47.4 


48.4 


49.5 


50.5 


51.6 


52.6 


53.6 


54.7 


55.7 


56.7 


57.7 


31.25 


+ 88.25 


46.9 


48.0 


49.0 


50.1 


51.1 


52.1 


53.2 


54.2 


55.2 


56.2 


57.3 


32.5 


+ 90.5 


46.4 


47.5 


48.5 


49.6 


50.6 


51.7 


52.7 


53.7 


54.8 


55.8 


56.8 


33.75 


+92.75 


46.0 


47.0 


48.1 


49.1 


50.2 


51.2 


52.2 


53.3 


54.3 


55.3 


56.4 


35 


+95 


45.5 


46.5 


47.6 


48.6 


49.7 


50.7 


51.8 


52.8 


53.8 


f>4.9 


55.9 


36.25 


4-97.25 


45.0 


46.0 


47.1 


48.2 


49.2 


50.3 


51.3 


52.4 


53.4 


54.4 


55.4 


37.5 


+99.5 


44.5 


45.6 


46.6 


47.7 


48.7 


49.8 


50.8 


51.9 


52.9 


53.9 


55.0 



442 



APPENDIX. 



TABLE VI. (continued.) 



Tempera- 
ture, 
degrees C. 


Tempera- 
ture, 
degrees F. 


64 


65 


66 


67 


68 


69 


70 


71 


72 


73 


74 


True strengths of spirit for the above apparent strengths. 


-25 


13 


76.2 77.1 ! 78.0 79.0 


79.9 


80.8 


81.7 


82.6 


83.5 


84.4 


85.3 


-23.75 


10.75 


75.9 76.8 77.7 78.6 


79.5 


80.4 


81.3 


82.2 


83.2 


84.1 


85.0 


-22.5 




-8.5 


75.5 76.4 77.3 78.2 


79.1 


80.1 


81.0 


81.9 


82.8 


83.7 


84.6 


-21.25 




-6.25 


75.1 ! 76.0 i 77.0 77.9 


78.8 


79.7 


80.6 


81.6 


82.5 


83.4 


84.3 


-20 


- 


-4 


74.8 i 75.7 76.6 77.5 


78.4 


79.3 


80.3 


81.2 


82.1 


83.0 


84.0 


-18.75 


1.75 


74.4 i 75.3 76.2 77.2 


78.1 


79.0 


79.9 


80.9 


81.8 


82.7 


83.6 


-17.5 


+0.5 


74.0 74.9 75.9 76.8 


77.7 


78.6 


79.6 


80.5 


81.4 


82.4 


83.3 


-16.25 




f275 


73.7 74.6 75.5 76.4 


77.4 


78.3 


79.2 


80.2 


81.1 


82.0 


82.9 


-15 


+ 5 


73.3 74.2 75.1 76.1 


77.0 


77.9 


78.9 


79.8 


80.7 


81.7 


82.6 


-13.75 


+ 7.25 


72.9 73.9 74.8 75.7 


76.7 


77.6 


78.5 


79.5 


80.4 


81.3 


82.3 


-12.5 


+ 9.5 


72.6 I 73.5 74.4 75.4 


76.3 


77.2 


78.2 


79.1 


80.1 


81.0 


81.9 


-11.25 


+11.75 


72.2 i 73.1 74.1 75.0 


75.9 


76.9 


77.8 


78.8 


79.7 


80.7 


81.6 


-10 


+ 14 


71.8 72.8 73.7 : 74.6 


75.6 


76.5 


77.5 


78.4 


79.4 


80.3 


81.3 


8.75 


+ 16.25 


71.5 ! 72.4 73.4 74.3 


75.2 


76.2 


77.1 


78.1 


79.0 


80.0 


80.9 


-7.5 


+ 18.5 


71.1 i 72.1 ; 73.0| 73.9 


74.9 


75.8 


76.8 


77.7 


78.7 


79.6 


80.6 


6 


+20.75 


70.7 i 71.7 72.6 | 73.6 


74.5 


75.5 


76.4 


77.4 


78.4 


79.3 


80.3 


5 


+23 


70.4 71.3 72.3 73.2 


74.2 


75.1 


76.1 


77.0 


78.0 


79.0 


79.9 


3.75 


+ 25.25 


70.0 71.0 71.9 72.9 


73.8 


74.8 


75.7 


76.7 


77.7 


78.6 


79.6 


2.5 


+ 27.5 


69.6 70.6 , 71.5 


72.5 


73.5 


74.4 


75.4 


76.3 


77.3 


78.3 


79.2 


1.25 


+29.75 


69.3 


70.2 71.2 


72.1 


73.1 


74.0 


75.0 


76.0 


77.0 


77.9 


78.9 





+32 


68.9 


69.8 


70.8 


71.8 


72.7 


73.7 


74.7 


75.6 


76.7 


77.6 


78.5 


+1.25 


+34.25 


68.5 


69.5 


70.4 


71.4 


72.3 


73.3 


74.3 


75.3 


76.2 


77.2 


78.2 


+2.5 


+36.5 


68.1 


69.1 70.0 


71.0 


72.0 


72.9 


73.9 


74.9 


75.9 


76.8 


77.8 


+3.75 


+38.75 


67.7 ' 68.7 69.6 


70.6 


71.6 


72.6 


73.5 


74.5 


75.5 


76.5 


77.4 


+ 5 


+41 


67.3 68.3 69.9 


70.2 


71.2 


72.2 


73.1 


74.1 


75.1 


76.1 


77.1 


+ 6.25 


+43 


66.9 67.9 I 69.3 


69.8 


70.8 


71.8 


72.8 73.7 


74.7 


75.7 


76.7 


+ 7.5 


+45.5 


66.5 


67.5 68.5 


69.4 


70.4 


71.4 


72.4 


73.4 


74.3 


75.3 


76.3 


+ 8.75 


+47.75 


66.1 67.1 68.1 


69.0 


70.0 


71.0 


72.0 


73.0 


74.0 


74.9 


75.9 


hio 


+ 50 


65.7 66.7 : 67.6 


68.6 


69.6 


70.6 


71.6 


72.6 


73.6 


74.6 


75.5 


-11.25 


+ 52.25 


65.3 66.3 67.2 


68.2 


69.2 70.2 


71.2 


72.2 


73.2 


74.2 


75.2 


-12.5 


+ 54.5 


64.8 65.8 66.8 


67.8 


68.8 


69.8 


70.8 


71.8 


72.8 


73.8 74.8 


-13.75 


+ 56.75 


64.4 65.4 66.4 


67.4 


68.4 


69.4 


70.4 


71.4 


72.4 


73.4 


74.4 


-15 


+ 59 


64.0 65.0 66.0 


67.0 


68.0 


69.0 


70.0 


71.0 


72.0 


73.0 


74.0 


-16.25 


+ 61.25 


63.6 64.6 65.6 


66.6 


67.6 


68.6 


69.6 


70.6 


71.6 


72.6 


73.6 


-17.5 


+ 63.5 


63.2 64.2 


65.2 


66.2 


67.2 


68.2 


69.2 


70.2 


71.2 


72.2 


73.2 


-18.75 


+ 65.75 


62.7 63.7 


64.7 


65.8 


66.8 


67.8 


68.8 


69.8 


70.8 


71.8 


72.8 


-20 


+ 68 


62.3 


63.3 


64.3 


65.3 


66.3 


67.4 


68.4 


69.4 


70.4 


71.4 


72.4 


-21.25 


+ 70.25 


61.9 


62.9 


63.9 


64.9 


65.9 


66.9 


68.0 


69.0 


70.0 


71.0 


72.0 


-22.5 


+72.5 


61.4 


62.4 


63.5 


64.5 65.6 


66.5 


67 5 


68.6 


69.6 


70.6 


71.6 


-23.75 


+74.75 


61.0 


62.0 


63.0 


64.1 65.1 


66.1 


67.1 


68.1 


69.2 


70.2 


71.2 


-25 


4-77 


60.5 


61.6 


62.6 


63.6 


64.6 


65.7 


66.7 


67.7 


68.7 


69.8 


70.8 


-26-25 




-79.25 


60.1 


61.1 


62.1 


63.2 


64.2 


65.2 


66.3 


67.3 


68.3 


69.4 


70.4 


-27.5 




-81.5 


59.6 


60.7 


61.7 


62.7 


63.8 


64.8 


65.8 


66.9 


67.9 


68.9 


70.0 


-28.75 




-83.75 


59.2 


60.2 


61.3 


62.3 


63.3 


64.4 


65.4 


66.4 


67.5 


68.5 


69.5 


-30 




-86 


58.7 


59.8 


60.8 


61.9 


62.9 


63.9 


65.0 


66.0 


67.1 


68.1 


69.1 


[-31.25 


+ 88.25 


58.3 


59.3 


60.4 


61.4 


62.5 


63.5 


64.5 


65.6 


66.6 


67.7 


68.7 


h32.5 


+90.5 


57.8 


58.9 


59.9 


61.0 62.0 


63.1 


64.1 


65.1 


66.2 


67.2 


68.3 


r 33.75 


+92.75 


57.4 


58.4 


59.5 


60.5 , 61.6 


62.6 


63.7 


64.7 


65.8 


66.8 


67.9 


r 35 


+95 


56.9 


58.0 


59.0 


60.1 ! 61.1 


62.2 


63.2 


64.3 


65.3 


66.4 


67.4 


[-36.25 


+97.25 


56.5 


57.5 


58.6 


59. 6 : 60.7 


61.7 


62.8 


63.8 


64.9 


65.9 


67.0 


[-37.5 


+99.5 


56.0 


57.1 


58.1 


59.2 60.2 


61.3 


62.3 


63.4 


64.4 


65.5 


66.6 



APPENDIX. 



443 



TABLE VI. (concluded.) 



? 
ill 

IH* 

* 


j 
\ 

1 


Cb 

si 

s to 

** <O 

a 


75 


76 77 


78 


79 


80 


81 


82 


83 


84 85 86 


True strengths of spirit for the above apparent strengths. 


25 


13 


86.2 


87.1 


88.0 88.9 


89.7 


90.6 


91.4 


92.3 


93.1 


93.9 94.7 95.5 


-^23.75 


10.75 


85.9 


86.8 


87.7 88.5 


89.4 


90.3 


91.1 


92.0 


92.8 


93.6 94.4 95.3 


22.5 




-8.5 


85.5 


86.4 


87.3 88.2 


89.1 


90.0 


90.8 


91.7 


92.5 


93.3 94.2 95.0 


21.25 


_ 


-6.25 


85.2 


86.1 


87.0 i 87.9 


88.8 


89.6 


90.5 


91.4 


92.2 


93.0 93.9 94.7 


20 


_ 


-4 


84.9 


85.8 


86.7 87.6 


88.5 


89.3 


90.2 


91.1 


91.9 


92.8 93.6 94.4 


18.75 


1.75 


84.5 


85.4 


86.3: 87.2 


88.1 


89.0 


89.9 90.8 


91.6 


92.5 93.3 94.1 


17.5 


+0.5 


84.2 


85.1 


86.0 86.9 


87.8 


88.7 89.6 90.4 


91.3 


92.2 93.0 93.8 


16.25 




-2.75 


83.9 


84.8 


85.7 j 86.6 


87.5 


88.4 


89.3 


90.1 


91.0 


91.9 92.7 93.6 


15 




-5 


83.5 


84.4 


85.4 86.3 


87.2 


88.1 


88.9 


89.8 


90.7 


91.6 92.4 93.3 


13.75 




-7.25 


83.2 


84.1 


85.0 85.9 


86.8 


87.7 


88.6 


89.5 


90.4 


91.3 92.1 93.0 


12.5 




-9.5 


82.9 


83.8 


84.7 


85.6 


86.5 


87.4 


88.3 


89.2 


90.1 


91.0 91.9 92.7 


11.25 


+11.75 


82.5 


83.5 


84.4 85.3 


86.2 


87.1 


88.0 


88.9 


89.8 


90.7 91.6 92.5 


10 


+14 


82.2 


83.1 


84.1 85.0 


85.9 86.8 


87.7 


88.6 


89.5 


90.4 91.3 92.2 


8.75 


+ 16.25 


81.9 


82.8 


83.7 : 84.7 


85.6 86.5 


87.4 


88.3 


89.2 


90.1 91.0 91.9 


7.5 


+18.5 


81.5 


82.5 


83.4 84.3 


85.3 86.2 


87.1 


88.0 


88.9 


89.8 90.7 91.6 


6 


+20.75 


81.2 


82.1 


83.1 ' 84.0 


85.0 85.9 


86.8 


87.7 


88.6 


89.5 90.5 91.4 


5 


+23 


80.9 


81.9 


82.8 , 83.7 


84.6 85.6 


86.5 


87.4 


88.3 


89.2 90.2 91.1 


3.75 


+25.25 


80.5 


81.5 


82.4 83.4 


84.3 l 85.2 


86.2 


S7.1 


88.0 


88.9 89.9 90.8 


2.5 


+27.5 


80.2 


81.1 


82.1 83.0 


84.0 


84.9 


85.9 


86.8 


87.7 


88.6 89.6 90.5 


1.25 


+29.75 


79.8 


80.8 


81.8 


82.7 


83.7 


84.6 


85.5 


86.5 


87.4 


88.3 89.3 90.2 





+32 


79.5 


80.4 


81.4 


82.4 


83.3 


84.3 


85.2 


86.2 


87.1 


88.0 89.0 1 89.9 


4-1.25 


+34.25 


79.1 


80.1 


81.1 


82.0 


83.0 


83.9 


84.9 


85.8 


86.8 


87.7 88.6 i 89.6 


+2.5 


+36.5 


78.8 


79.7 


80.7 


81.7 


82.6 J 83.6 


84.5 


85.5 


86.4 


87.4 88.3 89.3 


+3.75 


+38.75 


78.4 


79.4 


80.3 81.3 


82.3 i 83.2 


84.2 


85.2 


86.1 


87.1 i 88.0 89.0 


4-5 


+41 


78.0 


79.0 


80.0 81.0 


81.9 i 82.9 


83.9 


84.8 


85.8 


86.7 : 87.7 ; 88.6 


+ 6.25 


+43 


77.7 


78.6 


79.6 ! 80.6 


81.6 i 82.5 


83.5 84.5 


85.4 


86.4 87.4 88.3 


+7.5 


+45.5 


77.3 


78.3 


79.3 80.2 81.2 82.2 


83.2 


84.1 


85.1 


86.1 87.0 88.0 


+8.75 


+47.75 


76.9 


77.9 


78.9 79.9 


80.8 81.8 


82.8 


83.8 


84.8 


85.7 86.7 87.7 


+10 


+50 


76.5 


77.5 


78.5 79.5 


80.5 81.5 


82.4 


83.4 


84.4 


85.4 86.4 87.3 


+11.25 


+ 52.25 


76.2 


77.1 


78.1 79.1 


80.1 81.1 


82.1 


83.1 


84.1 


85.0 86.0 87.0 


+ 12.5 


+54.5 


75.8 


76.8 


77.8 78.8 


79.7 80.7 


81.7 


82.7 


83.7 


84.7 85.7 86.7 


+13.75 


+ 56.75 


75.4 


76.4 


77.4 


78.4 


79.4 


80.4 


81.4 


82.4 


83.4 


84.3 85.3 


86.3 


+ 15 


+ 59 


75.0 


76.0 


77.0 


78.0 


79.0 


80.0 


81.0 


82.0 


83.0 


84.0 85.0 


86.0 


+ 16.25 


+ 61.25 


74.6 


75.6 


76.6 


77.6 78.6 


79.6 


80.6 


81.6 


82.6 


83.6 84.6 


85.6 


+17.5 


+ 63.5 


74.2 


75.2 


76.2 


77.2 j 78.2 


79.2 


80.3 


81.3 


82.3 


83.3 84.3 


85.3 


+18.75 


+ 65.75 


73.8 


74.8 


75.8 


76.8 77.9 


78.7 


79.9 


80.9 


81.9 


82.9 83.9 


85 9 


+20 


+ 68 


73.4 


74.4 


75.1 


76.5 


77.5 


78.5 


79.5 80.5 


81.5 


82.6 83.6 


84.6 


+21.25 


+ 70.25 


73.0 


74.0 


75.7 


76.1 


77.1 


78.1 


79.1 


80.1 


81.2 


82.2 83.2 


84.2 


+22.5 


+ 72.5 


72.6 


73.6 


74.4 


75.7 


76.7 


77.7 


78.7 


79.8 


80.8 


81.8 82.9 


83.9 


+23.75 


+74.75 


72.2 


73.2 


74.3 


75.3 


76.3 


77.3 


78.4 


79.4 


80.4 


81.5 82.5 


83.5 


+25 


+77 


71.8 


72.8 


73.9 


74.9 


75.9 


76.9 


78.0 


79.0 


80.0 


81.1 82.1 


83.2 


+26.25 


+79.25 


71.4 


72.4 


73.5 


74.5 


75.5 


76.5 


77.6 


78.6 


79.6 


80.7 ' 81.7 


82.8' 


+27.5 


+ 81.5 


71.0 


72.0 


73.0 


74.1 


75.1 


76.1 


77.2 


78.2 


79.3 


80.3 81.4 


82.4 


+28.75 


+ 83.75 


70.6 


71.6 


72.6 


73.7 


74.7 


75.7 


76.8 


77.8 


78.9 


79.9 81.0 


82.0 


+30 


+ 86 


70.2 


71.2 


72.2 


73.3 


74.3 


75.3 


76.4 


77.4 


78.5 


79.5 80.6 


81.7 


+31.25 


+ 88.25 


69.7 


70.8 


71.8 


72.9 1 73.9 


74.9 


76.0 


77.0 


78.1 


79.1 80.2 


81.3 


+32.5 


+90.5 


69.3 


70.4 


71.4 


72.4 73.5 


74.5 


75.6 


76.6 


77.7 


78.7 79.8 


80.9 


+33.75 


+92.75 


68.9 


69.9 


71.0 


72.0 73.1 


74.1 


75.2 


76.2 


77.3 


78.3 79.4 


80.5 


+35 


+ 95 


68.5 


69.5 


70.6 


71.6 1 72.7 


73.7 


74.8 


75.8 


76.9 


77.9 79.0 


80.1 


+36.25 


+97.25 


68.1 


69.1 


70.1 


71.2 72.2 


73.3 


74.3 


75.4 


76.5 


77.5 78.6 


79.7 


+37.5 


+99.5 


67.6 


68.7 


69.7 


70.8 71.8 


72.9 


73.9 


75.0 


76.1 


77.1 j 78.2 


79.3 



444 



APPENDIX. 



TABLE VII. Determination of the true volume of alcoholic fluids 

from the apparent volume at different temperatures. 

(According to A. F. W. Brix.) 



Degrees C. 


Degrees F. 


55-57 


58-6o' 61-64 


65-69 


70-74 75-79 80-84 


85-89 


90-94 


Reducing factors for the above strengths of spirits of wine. 


10 


+ 14 


1.0198 1.0203J1.0207 1.0213 


1.0220 


1.0227 


1.0233 


1.0238 


1.0246 


8.75 


16.25 


0189 


0193 


0197; 0203 


0210 


0217 


0222 


0227 


0235 


7.5 


--18.5 


0180 


0183 


0187 0193 


0200 


0206 


0211 


0216 


0223 


6 


--20.75 


0170 


0173 


01771 0183 


0189 


0195 


0200 


0205 


0211 


5 


+23 


0161 


0164 


0168: 0173 


0179 


0185 


0190 


0194 


0200 


3.75 


+ 25.25 


0152 


0155 


0158! 0163 


0169 


0175 


0179 


0183 


0189 


2.5 


+ 27.5 


0143 


0146 


0148 


0153 


0159 


0164 


0168 


0172 


0178 


1.25 


+29.75 


0133 


0136 


0138 


0143 


0148 


0153 


0157 


0161 


0166 





+32 


0123 


0126 


0128 0132 


0138 


0142 


0146 


0150 


0154 


+1.25 


+34.25 


0114 


0117 


0118 0122 


0127 


0131 


0135 


0139 


0142 


+2.5 


4-36.5 


0105 


0107 


0108 


0112 


0116 


0120 


0124 


0128 


0130 


+ 3.75 


+ 38.75 


0095 


0097 


0098 


0102 


0105 


0109 


0113 


0116 


0118 


+ 5 


+41 


0085 


0087 


0088 


0091 


0094 


0098 


0101 


0104 


0106 


+ 6.25 


+43.25 


0075 


0077 


0078 


0080 


0083 


0086 


0089 


0092 


0094 


+ 7.5 


+45.5 


0066 


0067 


0068 


0070 


0072 


0075 


0078 


0080 


0082 


+ 8.75 


+47.75 


0056 


0057 


0058 


0060 


0061 


0064 


0066 


0068 


0070 


+10 


+ 50 


0046 


0047 


0048 


0050 


0050 


0053 


0054 


0056 


0058 


+ 11.25 


+ 52.25 


0036 


0037 


0038 


0039 


0039 


0041 


0042 


0044 


0045 


+ 12.5 


-j-54.5 


0026 


0027 


0027 


0028 


0028 


0029 


0030 


0031 


0032 


+ 13.75 


+56.75 


0015 


0016 


0016 


0017 


0017 


0017 


0018 


0019 


0019 


+15 


+ 59 


1.0005 


1.0005ll.0005 


1.0006 


1.0006 


1.0006 1.0006 


1.0006 


1.0006 


4-16.25 


+ 61.25 


0.9995 


0.9995 0.9995 


0.9995 


0.9994 


0.99940.9994 


0.9994 


0.9993 


+ 17.5 1 + 63.5 


9985 


99851 9984 


9984 


9983 


9983| 9982 


9982 


9981 


+ 18.75 


+65.75 


9975 


9975 


9974 


9973 


9972 


9971 9970 


9969 


9968 


+20 


+68 


9965 


9965 


9963 


9962 


9861 


9960 9958 


9957 


9955 


+-21.25 


+ 70.25 


9955 


9955 


9952 


9951 


9950 


9949 


9946 


9945 


9942 


+22.5 


+72.5 


9945 


9944 


9941 


9940 


9939 


9937 


9934 


9932 


9929 


+23.75 


+74.75 


9934 


9933 


9930 


9929 


9927 


9925 


9922 


9919 


9916 


+25 


+77 


9923 


9922[ 9919 


9917 


9915 


9912 


9909 


9906 


9903 


+26.25 


+79.25 


9912 


9911 


9908 


9906 


9903 


9901 


9897 


9893 


9890 


+ 27.5 1 + 81.5 


9901 


9900 


9897 


9894 


9891 


9889 


9885 


9880 


9877 


+ 28.75 


+83.75 


9890 


9889 


9886 


9882 


9879 


9876 


9872 


9867 


9864 


+ 30 


+86 


98791 9877 


9874 


9870 


9866 


9883 


9859 


9854 


9851 


+ 31.25 +88.25 


0.9868 


0.98650.9862 


0.9858 


0.9854 


0.9850 


0.9846 


0.9841 


0.9837 



Explanation of Table VII. 

Alcohol, or alcohol and water, heated above or cooled below the 
normal temperature expands or contracts. Now, for instance, what 
is the volume of 10,000 liters of a mixture of 82 per cent, by volume 
at +5 C. (41 F.) at the normal temperature.* In the horizontal 
column below 80-84 and in the vertical column at +5 C. (41 F.) 



The table is calculated for a normal temperature of 15.5 C. (60 F.). 



APPENDIX. 445 

is the reducing factor 1.0101 ; hence 1 0,000 liters are 10,000 X 1.0101 
= 10,101 liters. 82 being exactly the means of 80-84, the reduc- 
tion is accurate. At 83 the factor would have to be increased by 1 ; 
at 84 by f, and consequently the factor for 83 would be 1.0101 + 
(1.0104 1.0101) J = 1.01016. For the practice the above factors 
suffice without change. The measuring of the temperature and 
reading off of the percentage of spirit should be done in the storage- 
cellar, and not in a warmer room, for instance, the office, as is 
frequently the custom to the disadvantage of the seller. 



446 



APPENDIX. 



s 



O O OS Cfe OS QO GO Jt J 




i lO(N ( lDCOi l 



01 C O CO O CN t iO 



K 

3 
tx> 

B 



c- co "* k i> o o c co co <M 

OOiODtyD^C 







r-i! (i lOOOlOi 



2 >,i 



APPENDIX. 



447 



TABLE IX. For the reduction of specific gravities to 

saccharometer per cent. 
(According to Balling). Temperature 63.5 F. 





2 




2 




o 




2 




i 


i 


i 








* a 




5 a 








* n 




Ja 




o '" 




8- 









g'H 


8~ 






^ 


l 


^ 


y* 3 


^ 


* 


^ 


5 1 


K ~ 

' = 


^ 


* 


g 






11 


1 


s" 2 


I 


sS 


> 

g 


S 


"> 
2 


cl 

^ 


6C 


2 .- 




|c 




!- 




S.c" 


Sto 


f"l 


bo 


= K -l 


'5 


|I& 


1 


'Z a 


05 


Ill 


<D 
O. 


fell. 


1 


11! 


0) 




02 


u 


X 





an 


u 


W2 


6 


03 


6 


oT 


6 


1.0000 


0.000 


1.0040 


1.000 


1.0080 


2.000 


1.0120 


3.000 


1.0160 4.000 


1.0200 


5.000 


1.0001 


0.025 


41 


025 


81 


025 


121 


025 


161 


025 


201 


025 


2 


0.050 


42 


050 


82 


050 


122 


050 


162j 050 


202 


050 


3 


075 


43 


075 


83 


075 


123 


075 


163! 075 


203 


075 


4 


100 


44 


100 


84 100 


124 


100 


164i 100 


204 


100 


5 


125 


45 


125 


85 


125 


125 


125 


165 125 


205 


125 


6 


150 


46 


150 


86 


150 


126 


150 


166 150 


206 


150 


7 


175 


47 


175 


87 


175 


127 


175 


167 175 


207 


175 


8 


200 


48 


200 


88 


200 


128 


200 


168 200 


208 


200 


9 


225 


49 


225 


89 


225 


129 


225 


169 225 


209 


225 


1.0010 


250 


1.0050 


250 


1.0090 


250 


1.0130 


250 


1.0170 


250 


1.0210 


250 


11 275 


51 


275 


91 


275 


131 


275 


171 


275 


211 


275 


12 


300 


52 


300 


92 


300 


132 


300 


172 


300 


212 


300 


13 


3 OK 
M 


53 


325 


93 


325 


133 


325 


173 325 


213 


325 


14 


350 


54 


350 


94 


350 


134 


350 


1741 350 


214 


350 


15 


375 


55 


375 


95 


375 


135 


375 


175 375 


215 


375 


16 


400 


56 


400 


96 


400 


136 


400 


176 


401 


216 


400 


17 


425 


57 


425 


97 


425 


137 


425 


177 425 


217 


425 


18 


450 


58 


450 


98 


450 


138 


450 


178 450 


218 


450 


19 


475 


59 


475 


99 475 


139 


475 


1791 475 


219 


475 


1.0020 


500 


1.0061 


50C 


1.01 00 j 500 


1.0140 


500 


1.0180 500 


1.0220 


500 


21 


525 


61 


525 


1011 525 


141 


525 


181 525 


221 525 


22 


550 


62 


55C 


102| 55( 


142 


550 


182 


551 


222 


550 


23 


575 


63 


575 


103 575 


143 


575 


183 


575 


223 


575 


24 


600 


64 


600 


104 600 


144 


600 


184 


600 


224 


600 


25 


625 


65 


625 


105 


625 


145 


625 


185 


625 


225 


625 


26 


650 


66 


650 


106 


650 


146 


650 


186 


650 


226 


650 


27 


675 


67 


675 


107 


675 


147 


675 


187 


675 


227 


675 


28 


70C 


68 


700 


108 


70( 


148 


700 


188 


701 


228 


700 


29 


725 


69 


725 


109 


725 


149 


725 


189 


725 


229 


725 


1.0030 


750 


1.0070 


750 


1.0110 


751 


1.0150 


751 


1.0190 


751 


1.0230 


750 


31 


775 


71 


775 


111 


775 


151 


775 


191 


775 


231 


775 


32 


800 


72 


800 


112 


800 


152 


800 


192 801 


232 


800 


33 


825 


73 


825 


113 


825 


153 


825 


193 


82f 


233 


825 


34 


850 


74 


850 


114 


850 


154 


85C 


194 


85( 


234 


850 


35 


875 


75 


875 


115 


875 


155 


875 


195 


875 


235 


875 


36 


900 


7b 


900 


lib 


900 


156 


90C 


196 


900 


236 


900 


37 


92 


7*3 


925 


117 


925 


157 


925 


197 


925 


237 


925 


38 


95( 


78 


950 


118 


950 


158 


950 


198 95( 


238 


950 


39 


97 


79 


975 


119 


975 


159 


975 


199 975 


239 


975 



448 



APPENDIX. 



TABLE IX. (continued.) 



Specific gravity. 


Corresponding saccharo- 
meter, statement in 
per cent. 


. 


ng saccharo- 
;ement in 




2 

00 a 

^s 


. 


2 

d 

i| 


Specific gravity. 


Corresponding saccharo- 
meter, statement in 
per cent. 


bo 

o 

5 
o, 

02 


Corresponding saccharo- 
meter, statement in 
per cent. 

\atn ,.\, mil 


Specific gra\ 


Correspondi: 
meter, stal 
per cent. 


Specific gra\ 


If 
O 


Specific grav 


^ 
I 3 ' 


.0240 


6.000 


1.0290 


7.219 


1.0340 


8.438 


1.0390 


9.657 


1.0440 10.857 


1.0490 


12.047 


241 


024 


291 


244 


341 


463 


391 


681 


441 


881 


491 


071 


242 


048 


292 


268 


342 


488 


392 


706 


442 


904 


492 


095 


243 


073 


293 292 


343 


512 


393 


731 


443 


928 


493 


119 


244 


097 


294 


316 


344 


536 


394 


756 


444 


952 


494 


142 


245 


122 


295 


341 


345 


560 


395 


780 


445 


976 


495 


166 


246 


146 


296 


365 


346 


584 


396 


804 


44611.000 


496 


190 


247 


170 


297 


389 


347 


609 


397 


828 


447 


023 


497 


214 


248 


195 


298 


413 


348 


633 


398 


853 


448 


047 


498 


238 


249 


219 


299 


438 


349 


657 


399 


877 


449 


081 


499 


261 


1.0250 


244 


1.0300 


463 


1.0350 


681 


1.0400 


901 


1.0450 


095 


1.0500 


285 


251 


268 


301 


488 


351 


706 


401 


925 


451 


119 


501 


309 


252 


292 


302 


512 


352 


731 


402 


950 


452 


142 


502 


333 


253 


316 


303 


536 


353 


756 


403 


975 


453 


166 


503 


357 


254 


341 


304 


560 


354 


780 


404 


10.000 


454 


190 


504 


381 


255 


365 


305 


584 


355 


804 


405 


023 


455 213 


505 


404 


256 


389 


306 


609 


356 


828 


406 


047 


456 238 


506 


428 


257 


413 


307 


633 


357 


853 


407 


071 


457 261 


507 


452 


258 


438 


308 


667 


358 


877 


408 


095 


458 285 


508 


476 


259 


463 


309 


681 


359 


901 


409 


119 


459 309 


509 


500 


1.0260 


488 


1.0310 


706 


1.0360 


925 


1.0410 


142 


1.0460 


333 


1.0510 


523 


261 


512 


311 


731 


361 


950 


411 


166 


461 


359 


511 


547 


262 


536 


312 


756 


362 


975 


412 


190 


462 381 


512 


571 


263 


560 


313 


780 


363 


9.000 


413 


214 


463 404 


513 


595 


264 


584 


314 


804 


364 


024 


414 


238 


464 


428 


514 


619 


265 


609 


315 


828 


365 


048 


415 


261 


465 


452 


515 642 


266 


633 


316 


853 


366 


073 


416 


285 


466 


476 


516 


666 


267 


657 


317 


877 


367 


097 


417 


309 


467 


500 


517 


690 


268 


681 


318 


901 


368 


122 


418 


333 


468 


523 


518 


714 


269 


706 


319 


925 


369 


146 


419 


357 


469 


547 


519 


738 


1.0270 


731 


1.0320 


950 


1.0370 


170 


1.0420 


381 


1.0470 571 


.0520 


761 


271 


756 


321 


975 


371 


195 


421 


404 


471 595 


521 


785 


272 


780 


322 


8.000 


372 


219 


422 


428 


472 


619 


522 


809 


273 


804 


323 


024 


373 


244 


423 


452 


473 


642 


523 


833 


274 


828 


324 


048 


374 


268 


424 


476 


474 


676 


524 


857 


275 


853 


325 


073 


375 


292 


425 


500 


475 


690 


525 


881 


276 


877 


326 


097 


376 


316 


426 


523 


476 


714 


526 


904 


277 


901 


327 


122 


377 


341 


427 


547 


477 


738 


527 


928 


278 


925 


328 


.146 


378 


365 


428 


571 


478 


761 


528 


952 


279 


950 


329 


170 


379 


389 


429 


595 


479 


785 


529 


976 


1.0280 


975 


1.0330 


195 


1.0380 


413 


1.0430 


619 


1.0480 


809 


1.0530 


13.000 


281 


7.000 


331 


219 


381 


438 


431 


642 


481 


833 


531 


023 


282 


024 


332 


244 


382 


463 


432 


666 


482 


857 


532 


047 


283 


048 


333 


268 


383 


488 


433 


690 


483 


881 


533 


071 


284 


073 


334 


292 


384 


512 


434 


714 


484 


904 


534 


095 


285 


097 


335 


316 


385 


536 


435 


738 


485 


928 


535 


119 


286 


122 


336 


341 


386 


560 


436 


761 


486 


952 


536 


142 


287 


146 


337 


365 


387 


584 


437 


785 


487 


976 


537 


166 


288 


170 


338 


389 


388 


609 


438 


809 


488 


12.000 


538 


190 


289 


195 


339 


413 


389 


633 


439 


833 


489 


023 


539 


214 



APPENDIX. 



449 



TABLE IX. (concluded.) 





2 




A 




2 




6 




2 




o 




JI.S 




|.2 




5 d 




1.2 




2 




~ a 


. 


ii 


. 


Is 


, 


li 




li 




c ' 




00 


.-t? 


a 5 ! 


a 


g>l 


s 


ll 


25 


si 


.-*? 


*! 


.t? 


J 


1 


p "tc * 

o ^ ^ 


cS 
bo 


.- 


be 


111 


be 


Mi 


CC 

be 


ll- 


"> 

bo 


!** 


(9 


< 


u 









id 


p- *- g 





Isi 




ted 


h's 


"S 


^ 0} 


*o 


2^0} 


o 


S "^ CD 


'3 


* "^ fD 


g 


? 




S 


p. 
to 


I 8 ' 


Pi 

CO 


gap, 


P. 
CO 


JSP. 


0> 

PI 
co 


gap, 




CO 


I s * 


p. 

CO 


gsS, 




1.0540 


13.238 


1.057714.119 


1.0614 


15.000 


1.0651 15.860 


1.068816.721 


1.0730 


17.681 


541 


261 


578 


142 


615 


024 


652 


883 


689 


744 


732 


725 


542 


285 


579 


166 


616 


046 


653 


907 


1.0690 


767 


734 


772 


543 


309 


1.0580 


190 


617 


070 


654 


930 


691 


790 


7361 818 


544 


333 


581 


214 


618 


093 


655 


953 


692 


814 


7381 863 


545 


357 


582 


238 


619 


116 


656 


976 


693 


837 


1.0740 


909 


546 


381 


583 


261 


1.0620 


139 


657 


16.000 


694 


860 


742 


954 


547 


404 


584 


285 


621 


162 


658 


023 


695 


883 


744 18.000 


548 


428 


585 


309 


622 


186 


659 


046 


696 


907 


746 


045 


549 


452 


586 


333 


623 


209 


1.0660 


070 


697 


930 


748 


090 


1.0550 


476 


587 


357 


624 


232 


661 


093 


698 


953 


1.0750 


137 


551 


500 


588 


381 


625 


255 


662 


116 


699 


976 


752 


181 


552 


523 


589 


404 


626 


278 


663 


139 


1.0700 


17.000 


754 


227 


553 


547 


1.0590 


428 


627 


302 


664 


162 


701 


022 


756 


272 


554 


571 


591 


452 


628 


325 


665 


186 


702 


045 


758 


318 


555 


595 


592 


476 


629 


348 


666 


209 


703 


067 


1.0760 


363 


556 


619 


593 


500 


1.0630 


371 


667 232 


704 


090 


762 


409 


557 


642 


594 


523 


631 


395 


668 255 


705 


113 


764 


454 


558 


666 


595 


547 


632 


418 


669; 278 


706 


136 


766 


500 


559 


690 


596 


571 


633 


441 


1.0670 302 


707 


158 


768 


545 


1.0560 


714 


597 


595 


634 


464 


671 


325 


708 


181 


1.0770 


590 


561 


738 


598 


619 


635 


488 


672 


348 


709 


204 


772 


636 


562 


761 


599 


642 


636 


511 


673 


371 


1.0710 


227 


774 


681 


563 


785 


1.0600 


665 


637 


534 


674 


395 


711 


250 


776 


727 


564 


809 


601 


690 


638 


557 


675 


418 


712 


272 


778 


772 


565 


833 


602 


714 


639 


581 


676 441 


713 


295 


1.0780 


818 


566 


857 


603 


738 


1.0640 


604 


677 


464 


714 


318 


782 


863 


567 


881 


604 


761 


641 


627 


678 


480 


715 


340 


784 


909 


568 


904 


605 


785 


642 


650 


679 511 


716 


363 


786 


954 


569 


928 


606 


809 


643 


674 


1.0680 534 


717 


386 


788 


19.000 


1.0570 


952 


607 


833 


644 


697 


681 557 


718 


409 


1.0790 


045 


571 


976 


608 


857 


645 


721 


682: 581 


719 


431 


792 


090 


572 14.00C 


609 


881 


646 


744 


683| 604 


1.0720 


454 


794 


136 


573 


023 


1.0610 


14.904 


647 


767 


684i 627 


722 


500 


796 


181 


574 


047 


611 


928 


648 


790 


685 


650 


724 


545 


798 


227 


575 


071 


612 


952 


649 


814 


686 


674 


726 


590 


1.080019.272 


576 


095 


613 


976 


1.0650 


837 


687 697 


728 


636 







2!) 



450 



APPENDIX. 



TABLE X. Comparative synopsis of the areometers for 
must generally used. 



Specific gravity, 
degrees (Oechsle). 


Extract, per cent, 
by weight 
(Balling). 


Sugar, per cent, 
by weight. 


Degrees (Wagner). 


Specific gravity, 
degrees (Oechsle). 


Extract, per cent, 
by weight 
(Balling). 


Sugar, per cent, 
by weight. 


Degrees (Wagner). 


Babo. 


Pillitz. 


Babo. 


Pillitz. 


1.051 


12.5 


10.5 


8.2 


7 


91 


21.8 


18.3 


17.5 


_ 


52 


12.8 


10.7 


8.5 





92 


22.1 


18.5 


17.8 





53 


13.0 


10.9 


8.7 





93 


22.3 


18.6 


18.0 





54 


13.2 


11.1 


8.9 





94 


22.5 


18.8 


18.2 





55 


13.5 


11.3 


9.1 





95 


22.7 


18.9 


18.4 





56 


13.7 


11.5 


9.4 





96 


22.9 


19.0 


18.6 





57 


14.0 


11.7 


9.7 





97 


23.1 


19.2 


18.8 





58 


14.2 


12.0 


9.9 


8 


98 


23.3 


19.3 


19.0 





59 


14.4 


12.2 


10.1 





99 


23.5 


19.5 


19.2 


13 


60 


14.7 


12.4 


10.4 





1.00 


23.7 


19.7 


19.4 





61 


14.9 


12.6 


10.6 





01 


23.9 


19.9 


19.6 





62 


15.1 


12.8 


10.8 





02 


24.2 


20.1 


19. 9^ 





63 


15.4 


13.0 


11.1 





03 


24.4 


20.3 


20.1 





64 


15.6 


13.3 


11.3 





04 


24.6 


20.5 


20.3 





65 


15.8 


13.5 


11.5 





05 


24.8 


20.8 


20.5 





66 


16.1 


13.7 


11.8 


9 


06 


25.0 


21.0 


20.7 





67 


16.3 


13.9 


12.0 





07 


25.2 


21,2 


20.9 


14 


68 


16.5 


14.1 


12.2 





08 


25.4 


21.4 


21.1 





69 


16.8 


14.3 


12.5 





09 


25.7 


21.6 


21.4 


' 


70 


17.0 


14.4 


12.7 





10 


25.9 


21.8 


21.6 





71 


17.2 


14.6 


12.9 





11 


26.1 


22.0 


21.8 





72 


17.5 


14.8 


13.2 





12 


26.3 


22.2 


22.0 





73 


17.7 


15.0 


13.4 





13 


26.5 


22.4 


22.2 





74 


17.9 


15.2 


13.6 


10 


14 


26.7 


22.6 


22.4 





75 


18.1 


15.4 


13.8 





15 


26.9 


22.8 


22.' 6 





76 


18.4 


15.6 


14.1 





16 


27.1 


23.0 


22.8 


15 


77 


18.6 


15.8 


14.3 





17 


27-4 


23.2 


23.1 





78 


18.8 


15.9 


14.5 





18 


27-6 


23.5 


23.3 





79 


19.0 


16.1 


14.7 





19 


27.8 


23.8 


23.5 





80 


19.3 


16.3 


15.0 





20 


28.0 


24.1 


23.7 





81 


19.5 


16.5 


15.2 





21 


28.2 


24.3 


23.9 





82 


19.7 


16.7 


15.4 


11 


22 


28.4 


24.6 


24.1 





83 


20.0 


16.9 


15.7 





23 


28.6 


24.9 


24.3 





84 


20.2 


17.1 


15.9 





24 


28.9 


25.2 


24.6 





85 


20.4 


17.3 


16.1 





25 


29.1 


25.5 


24.8 


16 


86 


20.7 


17.4 


16.4 





26 


29.3 





25.0 





87 


20.9 


17.6 


16.6 





27 


29.5 





25.2 





88 


21.1 


17.8 


16.8 





28 


29.7 





25.4 





89 


21.4 


18.0 


17.1 





29 


29.9 





25.6 





90 


21.6 


18.2 


17.3 


12 


30 


30.1 





25.8 






APPENDIX. 



451 



TABLE XI. Table to Oechsle's areometer for must 





1 

bO 


8 Of 

sle's areo- 
r for must. 


-!_, r i-' 

03 

*.2 * 

^^ s 


. 

'> 

o 


8 Of 

sle's areo- 
r for must. 


'olS' 

D N io 

S?5S 


, 

"> 

o3 

So 


*of 
ile's areo- 
for must. 


118, 

5? 


gravity. 


I0f 

le's areo- 
for must.! 


"SIS 

&* 


d 

3 

0. 


2 

x 2 
03 


Its 

t* 


< 
p. 


Ill 


H 

a3 S U) 


0) 


S-g 
r r 
oS 


8&2 

S a 6c 


< 

1 


2 

*SI 


III 

; to 


to 





PH 


02 


p 


PH 


02 


a 







ft 




1041 


41 


8.0 


1059 


59 


13.0 


1076 


76 


17.2 


1093 


93 


21.7 


1042 


42 


8.3 


1060 


60 


13.2 


1077 


77 


17.5 


1094 


94 


21.9 


1043 


43 


8.6 


1061 


61 


13.4 


1078 


78 


17.8 


1095 


95 


22.2 


1044 


44 


8.9 


1062 


62 


13.6 


1079 


79 


18.0 


1096 


96 


22.5 


1045 


45 


9.2 


1063 


63 


13.9 


1080 


80 


18.3 


1097 


97 


22.7 


1046 


46 


9.4 


1064 


64 


14.0 


1081 


81 


18.5 


1098 


98 


23.0 


1047 


47 


9.7 


1065 


65 


14.2 


1082 


82 


18.8 


1099 


99 


23.2 


1048 


48 


9.9 


1066 


66 


14.4 


1083 


83 


19.1 


1100 


100 


23.4 


1049 


49 


10.2 


1067 


67 


14.7 


1084 


84 


19.4 


1101 


101 


23.7 


1050 


50 


10.5 


1068 


68 


15.0 


1085 


85 


19.7 


1102 


102 


23.9 


1051 


51 


10.8 


1069 


69 


15.2 


1086 


86 


20.0 


1103 


103 


24.2 


1052 


52 


11.1 


1070 


70 


15.5 


1087 


87 


20.2 


1104 


104 


24.5 


1053 


53 


11.4 


1071 


71 


15.8 


1088 


88 


20.4 


1105 


105 


24.8 


1054 


54 


11.7 


1072 


72 


16.1 


1089 


89 


20.7 


1106 


106 


25.0 


1055 


55 


11.9 


1073 


73 


16.3 


1090 


90 


20.9 


1107 


107 


25 2 


1056 


56 


12.2 


1074 


74 


16.5 


1091 


91 


21.2 


1108 


108 


25A 


1057 


57 


12.5 


1075 


75 


16.9 


1092 


92 


21.4 


1109 


109 


25.7 


1058 


58 


12.7 





















TABLE XII. To Massonfour's areometer. 



Degrees, 


Weight of a 


Degrees, 


Weight of a 


Degrees, 


Weight of a 


according to 
Massonfour. 


liter, 
grammes. 


according to 
Massoufour. 


liter, 
grammes. 


according to 
Massoufour. 


liter, 
grammes. 


1 


1008 


8 


1059 


15 


1116 


2 


1015 


9 


1067 


16 


1125 


3 


1022 


10 


1075 


17 


1134 


4 


1029 


11 


1083 


18 


1143 


5 


1036 


12 


1091 


19 


1152 


6 


1043 


13 


1099 


20 


1161 


7 


1051 


14 


1107 







TABLE XIII. For comparing per cent, of sugar with per cent. 
of extract and the specific gravity. By PiUitz. 



*> - 


j*r 




*8"-^ 


"? 




^^ 


- ci 


% 


B .Ni 
- * " 


tfl .5 


ojj> 


1-2 


"1 5 


^ 


~s*? 


tf|| 


<a t? 


& 


Ig^ 


o ^ 


Ss| 


* ""3 


0; u 


c ^ ~ 
bfid,^ 


- 1 


ll 


P.C- 






p s^C' 




ft so 


s p,C- 




M* ^ 


QQ 


CS 


cc 


02 


w 


cc 


W2 


w 







4.3 


1.0172 


9 


13.3 


.0543 


18 


22.3 


1.0930 


1 


5.3 


1.0212 


10 


14.3 


.0585 


19 


23.3 


1.0975 


2 


6.3 


1.0253 


11 


15.3 


.0627 


20 


24.3 


1.1017 


3 


7.3 


1.0294 


12 


16.3 


.0670 


21 


25.3 


1.1060 


4 


8.3 


1.0335 


13 


17.3 


.0713 


22 


26.3 


1.1103 


5 


9.3 


1.0376 


14 


18.3 


.0757 


23 


27.3 


1.1146 


6 


10.3 


1.0417 


15 


19.3 


.0800 


24 


28.3 


1.1189 


7 


11.3 


1.0459 


16 


20.3 


.0844 


25 


29.3 


1.1232 


8 


12.3 


1.0501 


17 


21.3 


.0887 









452 



APPENDIX. 



TABLE XIV. For determining the content of per cent, of acetic 
acid contained in a vinegar of specific gravity. Tempera- 
ture 15 C. (59 F.) 

(According to A. C. Oudemans.) 



Anhydrous 
acetic acid, 
per cent. 


Specific 
gravity. 


Anhydrous 
acetic acid, 
per cent. 


Specific 
gravity. 


Anhydrous 
acetic acid, 
per cent. 


Specific 
gravity. 


100 


1.0553 


66 


1.0717 


32 


1.0436 


99 


1.0580 


65 


1.0712 


31 


1.0424 


98 


1.0604 


64 


1.0707 


30 


1.0412 


97 


1.0625 


63 


1.0702 


29 


1.0400 


96 


1.0644 


62 


1.0697 


28 


1.0388 


95 


1.0660 


61 


1.0691 


27 


1.0375 


94 


1.0674 


60 


1.0685 


26 


1.0363 


93 


1.0686 


59 


1.0679 


25 


1.0350 


92 


1.0696 


58 


1.0673 


24 


1.0337 


91 


1.0705 


57 


1.0666 


23 


1.0324 


90 


1.0713 


56 


1.0660 


22 


1.0311 


89 


1.0720 


55 


1.0653 


21 


1.0298 


88 


1.0726 


54 


1.0646 


20 


1.0284 


87 


1.0731 


53 


1.0638 


19 


1.0270 


86 


1.0736 


52 


1.0631 


18 


1.0256 


85 


1.0739 


51 


1.0623 


17 


1.0242 


84 


. 1.0742 


50 


1.0615 


16 


1.0228 


83 


1.0744 


49 


1.0607 


15 


1.0214 


82 


1.0746 


48 


1.0598 


14 


1.0200 


81 


1.0747 


47 


1.0589 


13 


1.0185 


80 


1.0748 


46 


1.0580 


12 


1.0171 


79 


1.0748 


45 


1.0571 


11 


1.0157 


78 


1.0748 


44 


1.0562 


10 


1.0142 


77 


1.0748 


43 


1.0552 


9 


1.0127 


76 


1.0747 


42 


1.0543 


8 


1.0113 


75 


1.0746 


41 


1.0533 


7 


1.0098 


74 


1.0744 


40 


1.0523 


6 


1.0083 


73 


1.0742 


39 


1.0513 


5 


1.0067 


72 


1.0740 


38 


1.0502 


4 


1.0052 


71 


1.0737 


37 


1.0492 


3 


1.0037 


70 


1.0733 


36 


1.0481 


2 


1.0022 


69 


1.0729 


35 


1.0470 


1 


1.0007 


68 


1.0725 


34 


1.0459 





0.9992 


67 


1.0721 


33 


1.0447 







APPENDIX. 



453 



TABLE XY. For determining the content of per cent, of acetic 

acid contained in a vinegar of specific gravity. 

(According to Mohr.) 



Anhydrous 
acetic acid, 
per cent. 


Specific 
gravity. 


Anhydrous 
acetic acid, 
per cent. 


Specific 
gravity. 


Anhydrous 
acetic acid, 
per cent. 


Specific 
gravity. 


100 


1.0635 


66 


1.0690 


33 


1.0440 


99 


1.0655 


65 


1.0680 


32 


1.0420 


98 


1.0670 


64 


1.0680 


31 


1.0410 


97 


1.0680 


63 


1.0680 


30 


1.0400 


96 


1.0690 


62 


1.0670 


29 


1.0390 


95 


1.0700 


61 


1.0670 


28 


1.0380 


94 


1.0706 


60 


1.0670 


27 


1.0360 


93 


1.0708 


59 


1.0660 


26 


1.0350 


92 


1.0716 


58 


1.0660 


25 


1.0340 


91 


1.0721 


57 


1.0650 


24 


1.0330 


90 


1.0730 


56 


1.0640 


23 


1.0320 


89 


1.0730 


55 


1.0640 


22 


1.0310 


88 


1.0730 


54 


1.0630 


21 


1.0290 


87 


1.0730 


53 


1.0630 


20 


1.0270 


86 


1.0730 


52 


1.0620 


19 


1.0260 


85 


1.0730 


51 


1.0610 


18 


1.0250 


84 


1.0730 


50 


1.0600 


17 


1.0240 


83 


1.0730 


49 


1.0590 


16 


1.0230 


82 


1.0730 


48 


1.0580 


15 


1.0220 


81 


1.0732 


47 


1.0560 


14 


1.0200 


80 


1.0735 


46 


1.0550 


13 


1.0180 


79 


1.0735 


45 


1.0550 


12 


1.0170 


78 


1.0733 


44 


1.0540 


11 


1.0160 


77 


1.0732 


43 


1.0530 


10 


1.0150 


76 


1.0730 


42 


1.0520 


9 


1.0130 


75 


1.0720 


41 


1.0510 


8 


1.0120 


74 


1.0720 


40 


1.0510 


7 


1.0100 


73 


1.0720 


39 


1.0500 


6 


1.0080 


72 


1.0710 


38 


1.0490 


5 


1.0070 


7] 


1.0710 


37 


1.0480 


4 


1.0050 


70 


1.0700 


36 


1.0470 


3 


1.0040 


69 


1.0700 


35 


1.0460 


2 


1.0020 


68 


1.0700 


34 


1.0450 


1 


1.0010 


67 


1.0690 











454 



APPENDIX. 



TABLE XVI. Comparison of the scales of Eeaumur's, Celsius's, 
and Fahrenheit's thermometers. 



Reaumur. 


Celsius. 


Fahrenheit. 


Reaumur. 


Celsius. 


Fahrenheit. 


15 


18.75 


_ 


33 


41.25 


106.25 


14 


17.50 


0.50 


34 


42.50 


108.50 


13 


16,25 


2.75 


35 


43.75 


110.75 


12 


15.00 


5.00 


36 


45.00 


113.00 


11 


13.75 


7.25 


37 


46.25 


115.25 


10 


12.50 


9.50 


38 


47.50 


117.50 


9 


11.25 


11.75 


39 


48.75 


119.75 


8 


10.00 


14.00 


40 


50.00 


122.00 


7 


8.75 


16.25 


41 


51.25 


124.25 


6 


7.50 


18.50 


42 


52.50 


126.50 


5 


6.25 


20.75 


43 


53.75 


128.75 


4 


5.00 


23.00 


44 


55.00 


131.00 


3 


3.75 


25.25 


45 


56.25 


133.25 


2 


2.50 


27.50 


46 


57.50 


135.50 


+1 


1.25 


29.75 


47 


58.75 


137.75 








32.00 


48 


60.00 


140.00 


1 


1.25 


34.25 


49 


61.25 


142.25 


2 


2.50 


36.50 


50 


62.50 


144.50 


3 


3.75 


38.75 


51 


63.75 


146.75 


4 


5.00 


41.00 


52 


65.00 


149.00 ' 


5 


6.25 


43.25 


53 


66.25 


151.25 


6 


7.50 


45.50 


54 


67.50 


153.50 


7 


8.75 


47.75 


55 


68.75 


155.75 


8 


10 


50.00 


56 


70.00 


158.00 


9 


11.25 


52.25 


57 


71.25 


160.25 


10 


12.50 


54.50 


58 


72.50 


162.50 


11 


13.75 


56.75 


59 


73.75 


164.75 


12 


35.00 


59.00 


60 


75.00 


167.00 


13 


16.25 


61.25 


61 


76.25 


169.25 


14 


17.50 


63.50 


62 


77.50 


171.50 


15 


18.75 


65.75 


63 


78.75 


173.75 


16 


20.00 


68.00 


64 


80.00 


176.00 


17 


21,25 


70.25 


65 


81.25 


178.25 


18 


22.50 . 


72.50 


66 


82.50 


180.50 


19 


23.75 


74.75 


67 


83.75 


182.75 


20 


25.00 


77.00 


68 


85.00 


185.00 


21 


26.25 


79.25 


69 


86.25 


187.25 


22 


27.50 


81.50 


70 


87.50 


189.50 


23 


28.75 


83.75 


71 


88.75 


191.75 


24 


30.00 


86.00 


72 


90.00 


194.00 


25 


31.25 


88.25 


73 


91.25 


196.25 


26 


32.50 


90.50 


74 


92.50 


198.50 


27 


33.75 


92.75 


75 


93.75 


200.75 


28 


35.00 


95.00 


76 


95.00 


203.00 


29 


36.25 


97.25 


77 


96.25 


205.25 


30 


37.50 


99.50 


78 


97.50 


207.50 


31 


38.75 


101.75 


79 


98.75 


209.75 


32 


40.00 


104.00 


80 


100.00 


212.00 



INDEX 



ACCELEKATED acidulation, 97, 
99 
Acetal, 40, 41 

composition of pure, 41 
different views of the constitu- 
tion of, 41 
preparation of, 40 
properties of, 41 
Acetaldehyde or acetic aldehyde, 39, 

40 

Acetate, aluminium, 272-274 
ammonium, 270 
barium, 271, 272 
bismuth, 297 
calcium, 270, 271 
chromic, 279 
chromous, 279 
cobalt, 279 
dibasic cupric, 283 
ferrous, 275 
lead, neutral, 287-295 
magnesium, 272 
manganese, 274, 275 
mercuric, 298 
mercurous, 297, 298 
neutral cupric, 280-283 
ferric, 276-278 
formation of, 43 
nickel, 279 

of ammonia, neutral, 270 
of lead, composition, properties, 

and uses of, 293-295 
potassium acid, 268, 269 

neutral, 267, 268 
sesquibasic cupric, 283 
silver, 298 
sodium, 269, 270 
strontium, 272 
tin, 297 

tribasic cupric, 283 
uranium, 297 
zinc, 279 

Acetates and their manufacture, 266- 
298 



Acetates 

basic cupric, 283-287 

lead, 295-297 
chromium, 278, 279 
commercial, preparation of acetic 

acid from, 256-265 
iron, 275-278 
lead, 287-297 

obtained from wood-vinegar, pre- 
paration of acetic acid from, 
256-265 

of copper, 280-287 
preparation of, 267 
solubility of, 267 
used for the preparation of acetic 

acid, 256 
Acetic acid, 42-44 

and water, specific gravity of 

mixtures of, 42, 43 
application of, 43 
calculation for finding quan- 
tity of, in vinegar, 
209 

of the heat liberated by 
the conversion of al- 
cohol into, 46 
of the theoretical yield 
of, from alcohol, 44, 
45 
of the yield of, from 

malt, 158, 159 
cause of the large amount 
of, produced during the 
destructive distillation of 
wood, 219 
destruction of, by the vinegar 

ferment, 106 
determination of, 117 

by titration, with illus- 
tration, 208, 209 
of empyreumatic sub- 
stances in, 254 
of the content of, in 
vinegar, 112 



456 



INDEX. 



Acetic acid 

disturbances referable to the 
quantity of newly-formed, 
127-129 

formation of, by the action 
of platinum black, illus- 
trated, 24, 25 
for technical purposes, 240 
free, in the water of a river 

of Brazil, 24 
from calcium acetate, Volck- 

el's method, 258-261 
from lead acetate, 256, 257 
from sodium acetate, 262- 

265 

from strong vinegar, 255 
glacial, first obtained by 

Loewitz, 18 

influence of, upon the vine- 
gar ferment, 106 
in the mineral water of 

Briickenau, 24 
in wine, 177 
limit in vinegar of, 106 
method of fixing it on lime, 

256 

mode of obtaining, 42 
Mollerat's method of prepar- 
ing, illustrated, 263-265 
most suitable varieties of 

wood for, 229 
oil of lemon as a test of pure, 

266 

origination of, 23, 24 
preparation of, from com- 
mercial acetates and 
from those obtained 
from wood - vinegar, 
256-265 

of vinegar with a high 
percentage of, 119, 
120 
of, without distillation, 

257, 258 
principal acetates used for 

the preparation of, 256 
properties of, 42, 266 
pure concentrated, prepara- 
tion of, 253-266 
quantity of air required to 
convert alcohol into, 
45, 46 
of oxygen required for 

the formation of, 45 
replacement of hydrogen by 
a metal in, 266, 267 



Acetic acid 

samples for the determina- 
tion of, 122 
Schnedermann's method of 

preparing, 261, 262 
still for the rectification of, 

260 
strong, from copper acetate 

(verdigris), 18 
summary of the formation 

of, 37 

table of content of alcohol 
required in a liquid 
for the production of 
vinegar with a cer- 
tain content of, 108 
of theoretical yield of, 
from alcohol, 107, 108 
tables for determining the 
content of per cent, of, in 
vinegar of specific grav- 
ity, 452, 453 

theoretical yields of, 44-48 
theory of the formation of, 
established by Doberei- 
ner, 21 
variations in the specific 

gravity of, 42 

yields of, obtained in prac- 
tice, 48, 49 

aldehyde or acetaldehyde, 39, 40 
anhydride, determination of, in 
vinegar, or acetometry, 204- 
209 
ether, 40 

addition to vinegar of, 145 
composition and properties 

of, 174, 175 

preparation of, 173-175 
Acetometry or determination of acetic 

anhydride in vinegar, 204-209 
Acetone, crude, how obtained, 242 
or dimethyl ketone, 234, 235 
preparation of, from barium ace- 
tate, 271, 272 
properties of, 234, 235 
Acetous degeneration of wine, 177 

remedies for, 177 
fermentation, change of fusel oils 

in, 39 

induction of, 37 
products of, 38-49 
summary of the processes 

taking place in, 38 
Acid, acetic, 42, 44 

application of, 43 



INDEX. 



457 



Acid, acetic 

determination of chemical 

constitution of, 18 
discovery of the generation 

of, 18 

from verdigris, 18 
formation of, by the action 
of platinum black, illus- 
trated, 24, 25 
in the mineral water of 

Brttckenau, 24 
in the water of a river of 

Brazil, 24 

mode of obtaining, 42 
origination of, 23, 24 
properties of, 42 
summary of the formation 

of, 37 

theoretical yields of, 44-48 
theory of the formation of, 
established by Doberei- 

mer, 21, 22 
variations in the specific 

gravity of, 42 
and sugar, testing the must as to 

its content of, 324-327 
body, formation of, in the dry dis- 
tillation of wood, 18 
carbonic, 314, 315 
free, percentage of, in different 

varieties of fruit, 307 
glacial acetic, 18 
malic, decomposition of, 193 
succinic, 39 

formation and properties of, 

313, 314 

sulphurous, apparatus for the de- 
velopment of, illustrated, 

135, 136 

for the suppression of vine- 
gar eels, 134 

tartaric, decomposition of, 193 
to find the quantity of, in must, 

324, 325 

Acidity in cider, 349 
Acids, action of various, upon cel- 
lulose, 218 

of various, upon woods, 218 
detection of, in vinegar, 209-211 
disappearance of, in ripening 

fruits, 305 
in fruits, 309 
occurring in wood-vinegar, 246, 

247 

Acidulation, accelerated, 97-99 
object of, 96 



Acidulation 

of the generators, 96, 97 
Adulteration of cider, 350, 352 
Aerometer for must, Oechsle's, table 

to, 451 

Massonfour's, table to, 451 
Aerometers for must, table of com- 
parative synopsis of, 450 
table for comparing the clif. 
ferent, with Tralles's alco- 
holometer, 436 
Air, absorption of moisture by, 404, 

405 

difficulty in conveying the requi- 
site amount of, to the genera- 
tor, 53 

quantity of, required to convert 

alcohol into acetic acid, 45, 46 

quantity of, which must daily 

pass through each generator, 

46 

reciprocal action between the, 

and the vinegar, 144, 145 
Albucases, discovery of, how to obtain 

vinegar colorless, by, 18 
Albuminous substances in fruits, 309, 

310 

Alcohol, absolute, definition of, 313 
addition of. to the alcoholic 

liquid, 118 

and water, table showing the 
actual content of, in mixtures 
of both tin-ids, and the contrac- 
tion which takes places in mix- 
ing, 435 
calculation for the dilution of, 

109 

of the heat liberated by its 
conversion into acetic acid, 
46 
of the theoretical yield of 

acetic acid, from, 44, 45 
contraction of, in mixing with 

water, 116 
conversion of, into acetic acid 

and water, 38 
determination of, 110, 111, 117, 

198 
by means of the ebullioscope, 

201-204 
by the distilling test, 199- 

201 
of chemical constitution of, 

18 

with the alcoholmeter, 198, 
199 



458 



INDEX. 



Alcohol 

from wood, 217 

heat liberated by the oxidation 

of, 190 
influence of, upon the vinegar 

ferment, 106 

quantity of air required for the 
conversion of, into acetic acid, 
45, 46 

reduction of, with water, 116 
samples for the determination of, 

122 
table, Hehner's, 431, 432 

indicating the specific gravity 
of mixtures of water and, 
433 
of theoretical yield of acetic 

acid from, 107, 108 
the ultimate material for the fab- 
rication of vinegar, 51 
yield of acetic acid from, 195 

from sugar, 195 
Alcoholic ferment, 23 

fluid, arrangements for the distri- 
bution of the, in the gen- 
erator, illustrated, 61-65 
quantity of, to be daily 
worked in a generator, 116 
fluids, table for the determination 
of the true volume of, 
from the apparent vol- 
ume, 444, 445 
of proportion between 
per cent, by weight 
and by volume, 434 
liquid, addition of alcohol to the, 

118 

of beer, sweet beer- wort, 
malt extract, etc., to, 
126 

of phosphates to, 127 
apparatus for heating the, 
illustrated and described, 
94-96 

constitution of the funda- 
mental materials used in 
the preparation of, 112- 
115 

definition of, 104 
disadvantages of pouring the, 
at stated intervals, 80-82 
examples of the composition 

of, 109 

gradual strengthening of, 11 7 
methods of preparing, 105 



Alcoholic liquid 

preparation of, 104-115 

of, according to rational 

principles, 111, 112 
of, for 1 2 per cent, vin- 
egar, 123 

quantities of beer and vine- 
gar for, 107 
receipts for, 109 
the role of vinegar in, 104 
use of simple automatic con- 
trivances for the effusion 
of the, 82 
mashes as material for vinegar, 

156 
Alcoholometer determination of the 

alcohol with the, 198, 199 
Alcoholometers, 198 

for use in a vinegar factory, 199 
Aldehyde and its composition, 22 
derivation of the term of, 39 
formation of, 39 
preparation of pure, 40 
properties of pure, 40 
Alden apparatus, illustrated and de- 
scribed, 407-409 
manner of operating the, 

413, 414 

process, prize awarded at the 
Paris exhibition to fruit dried 
by the, 402 

Ale, sour, as material for vinegar, 162 
Alkaloid in wine, 315 
Aluminium acetate, 272-274 
American canning factories, secret of 
the great reputation of the 
products of, 391 
champagne, 329 
ciders, adulteration of, 352 
fruit evaporator, illustrated and 

described, 412, 413 
Manufacturing Co., fruit evapo- 
rator manufactured by, illus- 
trated and described, 412, 413 
preserving establishments, kettle 
used in, illustrated and de- 
scribed, 399, 400 
Ammonia solution of, 207 
Ammonium acetate, 270 
Amyl acetate, 114 

addition to vinegar of, 145 
Analyses of ciders by the U. S. Agri- 
cultural Department, 331, 332 
Anchovy vinegar, 172 
Anise vinegar, 172 



INDEX. 



459 



Anthon's tables for finding the content 
of anhydrous grape-sugar in a solu- 
tion of glucose, 328, 329 
Apparatus, continuously acting ; the 

terrace system, 82-87 
periodically working ; the three- 
group system, 87-90 
Apple-butter, manufacture of, 388, 

389 

elevator, illustrated and de- 
scribed, 323, 324 
grinder, Davis' s, illustrated and 

described, 317, 318 
jelly, favorite package for, 397, 

398 
manufacture of, in Oswego 

Co., N. Y., 394-399 
proper consistency of, 397 
without sugar as made in the 

U. S., 392, 393 
marmalade, perfumed, 392 
pomace, expression of, 335, 336 

vinegar from, 168 
seeds, diversity of opinion as re- 
gards the crushing of, 335 
value of, 398 

wine, red, preparation of, 343 
Apples and pears, cider from, 329-356 
bleaching of, 415, 416 
choice of varieties of, in the man- 
ufacture of cider, 332 
cider from, 329-354 
crushing mill for, illustrated and 

described, 317 

evaporated and dried, export of 
from the U. S., in 1888, 
401, 402 

packing of, 414, 415 
extraction of the juice of, by dif- 
fusion, 336-339 
fermentation of the juice of, 339, 

340 

grinding of, 335 
most noted varieties of, for the 

manufacture of cider, 333 
preparation of the juice of, for 

distillation, 353 
prices paid in 1880 and 1881 for, 

. 39 
ripening, gathering, and sweating 

of, 334 
select list of, for the Eastern and 

Middle States, 333, 334 
table of changes effected in the 

composition of, by drying and 

evaporating, 406 



Apples and pears 

test for tannin in the juice of, 

333 

testing the juice of, 339 
Apricot and peach wines, preparation 

of, 369 
Aromatic or hygienic mustard, 426 

vinegar, 171 

Aromatized vinegar, 169 
Arrangement of a vinegar factory, 68- 

72 

according to the 
automatic princi- 
ple, 90-96 

of the generators, 54-65 
Artificial ventilation of the vinegar 

generators, 73-80 
Assmus, products obtained from wood 

by, 252 

Au Baine-Marie, method of pre- 
serving, 372 
Automatic contrivance, regulation of 

the, 124 
vinegar apparatus, 80-96 



BACHET, experiments by, 218 
Bacteria, 26, 27 
Bag-filter for vinegar, illustrated and 

described, 151, 152 
Barberries, pickling of, 422 
Barium acetate, .271, 272 
Baroulier, observations on wood, by, 

217 

Barrels, filling of, 144 
Barry, P., apples for cider, recom- 
mended by, 333 
select list of apples for the 
Eastern and Middle States, 
recommended by, 333, 334 
Basic cupric acetates, 283-287 

lead acetates, 295-297 
Beans, pickling of, 422 
Beech, products obtained from the dis- 
tillation of, 251 
shavings, active surface of, 66 
drying of, 67 

manner of filling the genera- 
tor with, 68 
number of, required for a 

generator, 66 
size of, for generators, 66 
steaming of, 66, 67 
swelling of, 67 

Beechwood shavings for filling gene- 
rators, 65 



460 



INDEX. 



Beer, determination of vinegar from, 

213 

nourishing fluid from, 101 
quantity of, for alcoholic liquid, 

107 

sour, as material for vinegar, 162 
wort as material for vinegar, 155, 

156 
Bell-siphon, described and illustrated, 

89 

Benzol, 220 
Berard, method of preparing sugar of 

lead recommended by, 291, 292 
Bergot, M., on the crushing of apple- 
seeds, 335 

Berries, bouquet of vinegar from, 166 
difficulty in the complete fermen- 
tation of the juice of, 165 
fruits and sugar, vinegar from, 

163-166 
jelly from, 393 
manner of obtaining juice from, 

318 

Bersch, Dr. J., condensing apparatus 
according to, illustrated, 
78-80 

description of vinegar-mite 
by, with illustrations, 137, 
138 

execution of his process of 
manufacturing wine-vine- 
gar on a commercial scale, 
188-193 

method of the fabrication of 
wine-vinegar, according to, 

185-188 

ventilating apparatus, ac- 
cording to, illustrated, 77, 
78 

Berzelius, determination of the chemi- 
cal constitution of acetic acid by, 
18 
Bilberries, use of, for the preparation 

of vinegar, 166 
Birch, products obtained by Rothe 

from, 252 

products obtained from the dis- 
tillation of, 251 
Bismuth acetate, 297 
Blackberry wine, preparation of, 366 
Boerhaave, method for the fabrication 
of vinegar from wine made known 
by, 19 

Boiling of wine-vinegar, 180 
Bois-roux, 230 
Bottling cider, directions for, 344, 345 



Bouquet bodies, 20 

Braconnot, experiments on cellulose 

by, 218 

Brandy from plums and damsons, 353 < 
manufacture of, from cider, 352- 

354 
Brazil, free acetic acid in the water 

of a river of, 24 
Bremont, Dr., on the adulteration of 

cider, 351 

Brewing, division of labor in, 155 
Brittany cider, analyses of, 330 
Briickenau, acetic acid in the mineral 

water of, 24 

Bucholz, direction for the preparation 
of acetic acid from lead acetate by, 
257 
Burette, the, illustrated and described, 

204-206 

Burgundy from cider, 348 
Burnt sugar, preparation of, 154 
Bushnell Company, apple elevator 
manufactured by, illustrated and 
described, 323, 324 
Bushnell Company. Da vis's star apple 
grinder manufactured by, 
illustrated and described, 
317, 318 

extra power cider press, il- 
lustrated and described, 
319, 320 

farmer's cider press manu- 
factured by, illustrated and 
described, 319 



CABBAGE, pickling of, 422 

\J Cadet-Gassicourt, receipts for 

vinegar by, 164 
Calcium acetate, 270, 271 

acetic acid from, 258 

crude preparation of, 241, 

242 
destruction of empyreumatic 

bodies in crude, 261 
chloride, 265 
Calico-printing, mordants for, 272- 

274 
California, evaporation of fruit in, 

402 

size of tin-cans in, 377 
Canned articles, groups of, embraced 

in American trade lists, 374 
goods, unreliability of, 402, 403 
Canner, life trials and vexations of a, 
384 



INDEX. 



461 



Canneries, division of labor in the 

American, 379 
manufacture of tin cans in the 

American, 379 
preparation of sugar- syrup in, 

379, 380 

Canning and evaporating of fruit, 
manufacture of catchups, fruit- 
butters, marmalades, jellies, 
pickles, and mustard, 371- 
427 
factory, arrangement of a, 381, 

382 

fruits, national importance of, 
for the United States and Eng- 
land, 374 
fruits, suitable and unsuitable for, 

375 

varieties of fruits preferred by the 
North American factories for, 
375, 376 
Cans, apparatus for the expulsion of 

air from, 379, 380 
bath for, 383 
importance of, 376 
labelling of, 383 
method of heating in boiling 

water, 380 

preserving in air-tight, 374-385 
steaming of, 379 
testing of, 383 

"Cappers" and their work, 383 
Caramel, preparation of, 154 
Carbonate of lead by the Clichy and 

the Dutch processes, 296 
Carbonic acid, 314, 315 

quantity of, developed dur- 
ing fermentation, 315 
Casks, acidulation of, 182 
Catchups, 385-388 
Cauliflower, pickling of, 422 
Celery vinegar, 173 
Cellulose, action of alkaline solutions 

upon, 218 

action of various acids upon, 218 
composition of, 215 
conversion of, into dextrin and 

starch, 217 
conversion of, into gun-cotton, 218 
Champagne cider, 329 

manufacture of, 347, 348 
gooseberry, 363-365 
Charbon roux, 230 
Charcoal, 230-232 

apparatus for the abstraction of, 
227 



harcoal 

composition of, 230 
for filling generators, 65 
influence of the degree of carbon- 
ization and of the variety of 
wood upon the yield of, 231 
properties of, 232 
quantity of, obtained at various 

temperatures, 231 
torrified, 230 
wood-vinegar, wood-spirit, and 

tar, yield of, 250-253 
Charcoals, difference in the elemen- 
tary composition of, 231 
for technical purposes, 230, 2.31 
Chemical examination of the raw ma- 
terials and control of the operations 
in a vinegar factory, 197-209 
Cherries, difficulties in canning, 375 
Cherry-wine, preparation of, 368 
Chillies in vinegar, determination of, 

214 
Christl, acetic acid obtained from lead 

acetate by, 258 
Chromic acetate, 279 
Chromium acetates, 278, 279 
Chromous acetate, 279 
Cider, acidity in, 349 

adulteration of, 350-352 

and fruit-wines, practice of the 

preparation of, 316-329 
artificial wines from, 348, 349 
clarification of, 342 
Devonshire, 345 
directions for bottling, 344, 345 
diseases of, 349, 350 
distillation of, 353, 354 
for export, treatment of, 342 
freezing of, 346, 347 
from apples, 329-354 
from apples and pears, 329-356 
heating of, 345, 346 
manufacture of brandy from, 

352-354 
manufacture of, in the Island of 

Jersey, 345 
mill, English, 316 

portable, invented by \> . (J. 

Hickock, 316 

Willson's telegraph, illus- 
trated and described, 322, 
323 

minimum limit for the composi- 
tion of pure, 351 
modes of improving the taste of, 
342, 343 



462 



INDEX. 



Cider- 
preparation of, in the same 
manner as other fruit-wines, 
343 
press, "extra power," illustrated 

and described, 319, 320 
" Farmer's," illustrated and 

described, 319 

sweet, preparation of, 343, 344 
turbidity of, 350 
turning black of, 350 
vinegar, 16G-168 
viscosity or greasy appearance of, 

349, 350 
'what it is, 166 

Ciders, analyses of, by the U. S. 
Agricultural Depart- 
ment, 331, 332 
of, from different parts of 

France, 330 
fruit-wines, etc., manufacture of, 

299-369 

type of composition for pure, 331 
Claret-wine from cider, 349 
Cleopatra, solution of large pearls in 

vinegar by, 1