regarded as the hide proper, that is to say, as the animal tissue
saturated with tannic acid. In this remainder one is able to estimate
with close precision that which belongs to the hide. The hide being an
elementary tissue of unchangeable form, it is easy, in determining the
elementary portion, to find the amount of real hide remaining in the
product. With these elements one can arrive at a solution of some of the
questions we are discussing.

We give below, according to this method, a table showing the composition
of the different leathers exhibited at the Paris Exposition of 1878.
They are the results of careful research, and we have based our work
upon them:

Matter Soluble Fixed
in Air Tannin
| |
| Matter Solu- |
| ble in Alcohol |
| | |
Moisture | | Gelatine |
--+-- --+-- --+-- --+-- --+--
Steer hide, hemlock tanned (heavy leather) 10.95 4.15 19.77 39.1 26.03
Sheepskins, sumac " (Hungarian) 10.8 10.3 12.1 40.3 26.5
Finished calf, pine bark tanned (Hungarian) 11.2 1.7 7.4 41.6 38.1
Steer hide, quebracho tanned (heavy leather) 11.7 1.6 11.2 43.1 32.4
" " chestnut " " " 13.5 0.29 1.99 45.46 38.76
Finished calfskins,
oak tanned (Chateau Renault) 12.4 0.33 3.59 46.74 36.94
Steer hide, laurel tanned (heavy leather) 12.4 1.05 7.95 47.47 31.13
" " oak tanned after three years in