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duction of beer, ale, and porter, which is appropriately illustrated by means of samples © 
taken from different stages in the process of manufacture. 
By distillation of fermented amylaceous substances we have the production of 
whisky. This important branch of industry is represented by samples of grain gen- 
erally employed in the manufacture, both in the raw state and as prepared for fermen- 
tation; samples of the yeasts and mashes necessary to the production of different 
varieties of whisky, and the fermented mashes or beer. Following these are the plans 
of an American distillery and a model still, succeeded by the distillates in different 
stages of concentration and rectification. 
By fermentation of saccharine substances we have the production of wines; and 
from distillation of the fermented products, brandy results. This branch of manufac- 
ture is represented by samples of American wines and brandies. 
The fourth group contains specimens intended to show the chemical changes involved 
in the preparation of tobacco for consumption. These changes in the character of the 
leaf for chewing and for snuff, consist in sweetening and fermenting, and the prodncts 
necessary to the illustration of these changes are therefore shown. 
Group 5 is one of great interest and importance in this country, and contains speci- 
mens of the materials used for tanning and dyeing. The tanning materials consist of 
samples of barks, herbs, and leaves. Among the herbs and leaves are those lately dis- 
covered to be of value in this particular, viz, the Ephedra antisyphillitica and the 
Polygonum amphibium. The manufacture of tanning extracts from hemlock and oak 
barks, both for home consumption and for exportation, is represented by the barks, 
the raw and the concentrated extract. The American dyes are represented by sam- 
ples illustrating the manufacture of flavine from oak bark, indigo produced from na- 
tive plants, and by barberry root, orchilla weed, cudbear, &c. 
In the next group follows a series containing the products resulting from the dry 
distillation of vegetable products. This group may be divided into two parts, viz, 
distillation of wood for production of crude acetic (pyroligneous) acid and acetates ; 
and distillation of pive-tree products for production of turpentine and rosin. The crude 
acetates are used largely for mordants in the process of dyeing, and they are therefore 
accompanied by specimens showing their application in calico-printing. They are 
further used for the production of pure acetic acid. : 
The pine-tree products consist of different grades of virgin dip, turpentine, rosin, 
tar, and pitch, arranged in the order of their production. 
The production of vegetable oils involves two processes—that of expression and that 
of fractional distillation—necessary to the separation of fixed oils from seeds, and of the 
essential or volatile oils from herbs and leaves. Of the fixed oils manufactured on a 
large scale, and the production of which constitutes important branches of industry in 
this country, we have three, viz, cotton-seed oil, linseed oil, and castor oil, and these 
oils, with the waste material pertaining to their production, constitute Group 8 of the 
second grand division. 
The method for the production of oil from cotton-seed consists, essentially, of three 
parts, viz, removing the hull, crushing the seed, and removal of the oil by pressure. 
The production of oils from other seeds requires only the last two processes, the first 
being unnecessary. The specimens in this group, therefore, necessarily consist of raw 
seeds, decorticated or hulled seed, hulls, crushed seed or meals, raw oil-cake or resi- 
due from the press, and refined oil. The cotton-seed series is accompanied by speci- 
mens of the varieties of soap manufactured from the oil. Of the essential or volatile 
oils, we have eighteen varieties manufactured from indigenous products, and samples 
of each of these oils are found in this group. 
Group 8 is intended to illustrate the methods employed for the preservation of fruits 
and vegetables. Those most extensively in use in this country are hermetically seal- 
ing, packing in sugar or sirup, and desiccation, and the specimens, consequently, con- 
sist of fruits preserved by these methods. This group also contains a series of vege- 
table products prepared for food by special methods, contributed by E. C. Hazard & 
Co., New York City. 
Group 9 contains a series of American drugs, consisting of specimens of herbs, roots, 
and leaves, having medicinal properties, and are accompanied by their active proxi- 
mate principles, (alkaloids, resins, or oils, as the case may be,) which have been sepa- 
rated. This group was prepared under the direction of Prof. E. 8. Wayne, of Cincin- 
nati, and contains some principles never separated before. 
The collection illustrating the manufacture of butter and cheese is well described 
in the following terms by Prof. G. C. Caldwell, of Cornell University, Ithaca, N. Y., 
who has had charge of the preparation and analysis of the samples: 
“The collection for the illustration of the manufacture of the products of the dairy, 
prepared and analyzed at the laboratory of agricultural chemistry in Cornell University 
at the request of the Department of Agriculture, and placed in its exhibit at the Cen- 
tennial, consists of samples obtained directly from dealers in dairy supplies, or from 
factories or private manufacturers of butter or cheese. 
It begins naturally with salt, rennet, and annotto—the first being universally used 
