human
for producing the first requirements; _i.e._ an attempt is made to dry the fibres separately in an
gpt
condition, and to coat them simultaneously with fat so that a permanent leather is obtained. It is only possible to do this, if the pelt is constantly during drying subjected to mechanical working, _e.g._ by twisting, folding, bending, drumming, staking, etc. The resulting leather is often called
human
and presents a real advantage over other leathers in its great tensile strength. Where toughness is an essential quality, there is much to be said for the fat tannages. It is also possible, of course, to effect compromises between ordinary tannages and the straight fat tannages; thus picking band butts, which must be tough, are often very lightly tanned with oak bark or chrome, and then given what is practically a heavy fat tannage. In the most typical of fat tannages, moreover, it is often common to