1872.] Technology. 109 
A cheap and good process for the utilisation of leather waste has long been 
a desideratum. This waste represents millions of dollars annually. A pro- 
cess that could reproduce a texture of these cuttings, only half as good as the 
original leather, would be one of national importance, and would at once 
establish a new industry. The ‘Scientific American” describes a process 
invented by Mr. P. J. McKenzie Oerting, which is said to make uniformly an 
artificial leather even superior to ordinary tanned sole leather. Examination 
of these specimens reveals the following facts:—It is much harder than 
ordinary leather, and does not yield to hammering or compression nearly as 
much. It is very flexible and elastic. Thin shavings of it possess as great 
tensile strength as shavings of equal thickness of common oak-tanned leather. 
It is nearly, if not quite, impervious to water. It cuts smoothly and easily 
in working. With regard to its durability under wear, it would probably wear 
longer than sole leather, as it is said not to decompose or change under the 
ordinary circumstances of wear to which leather is exposed in its various uses. 
The method under consideration was first brought out in Copenhagen. 
The ingredients employed and their proportions are as follows :—For first 
quality, one pound caoutchouc for each three and a quarter pounds leather 
pulp. For other qualities, the proportion of leather pulp is increased variously 
up to six pounds for one pound of caoutchouc. The caoutchouc is dissolved 
in benzol or other solvents, and, when sufficiently dissolved aqua ammonia 
is added in the same proportion as that of the rubber, and the mass is 
thoroughly stirred until it assumes a grayish-white colour. The leather pulp 
is then added, and the whole is kneaded into a plastic homogeneous dough of 
uniform consistency, which can be pressed or moulded into any required form, 
or rolled into sheets, as may be required. The ammonia is said to a& 
upon the animal glue in the cuttings, restoring to it its original properties 
which it had lost to a great degree in the process of tanning. The following 
are some of the properties and uses of this remarkable substance, as 
given by Mr. Oerting:—Its waterproof quality makes it especially valuable 
for pump leather, as well for cold as hot water, and also for harness, 
as even a continued exposure to all kinds of weather has no effe& on it, 
occasioning neither rot nor crack. It can be made endless, or of any length, 
width, and thickness required, and of perfect uniformity as to wear, which is 
generally well known to be impossible with leather belts made of shorter 
pieces of different hides, and of unequal wearing capacity. It will stand any 
amount of heat and fri@tion, as well as the most intense cold, will stretch less 
than any other belting, and can be changed from one pulley to another with 
ease and rapidity. It is very strong and substantial in the edge, and will stand 
a great amount of ill use without suffering any injury, and through its com- 
bined properties will supply a desideratum much needed. By suitable 
machinery for moulding, or forming the material in its doughy state into hose, 
fire buckets, &c., for which purpose it is especially adapted on account of its 
flexibility, impenetrability by water, and its capacity to withstand any amount 
of hardship, as well as extreme heat or cold, it will certainly make the 
best as also the cheapest material yet produced for such purposes. By 
a different mixture and proportion of the ingredients, a matting for floor 
covering is made, which on account of its cheapness, its waterproof proper- 
ties, and its capacity to keep rooms protected from cold and dampness, makes, 
it is said, an unequalled article for covering offices, passage ways of public 
buildings, &c., which will withstand an immense amount of wear, and can very 
easily be cleaned. 
At a recent meeting of the Manchester Literary and Philosophical Society,. 
Mr. John Hopkinson, B.A., D.Sc., detailed some experiments on the subject of 
the rupture of iron by a blow, the results of which are—ist. That if any 
physical cause increase the tenacity of wire, but increase the produé of its 
elasticity and linear density in a more than duplicate ratio, it will render it 
more liable to break under a blow. 2nd. That the breaking of wire under a 
blow depends intimately on the length of the wire, its support, and the method 
of applying the blow. 3rd. That in cases such as surges on chains, &c., the 
