English basils are tanned with oak bark, although, as in all other leathers, inferior tannages are now common; Scotch basils are tanned with larch bark, Australian and New Zealand basils with mimosa bark and Turkish basils with galls.
Generally, the best mixed tannages for solid leather consist of a combination of both pyrogallol and catechol tannins.
Barium compounds are also used for the same purpose, but the American tannages are apparently free of this adulterant.
A basic iron salt might also be useful, but iron tannages would only be suitable for black leather.
The adaptation of combined tannages in the manufacture of gloving leathers has only lately been developed, and further improvements will doubtless be effected before long.
Hitherto, rapid tannages have not been very successful, as they generally made the leather harsh and brittle, and lessened its durability.
Other noteworthy vegetable tannagesare those used in the production of Russia leather, and a large proportion of East India leather.
Combination tannages have lately been produced, however, which remove the defects of alumed leather.
In the fat tannages an attempt is made to fulfil this second requirement without the use of any specific "tanning agent" for producing the first requirements; i.
The same tendency to save labour in handling is to be observed in upper leather tannages as in sole and other dressing leather factories.
Wilson refers to the well-known practical fact that chrome leather can take up about as much vegetable tan as if it were unchromed pelt, and considers this evidence that the two tannages are of fundamentally different nature.
To the writer, however, it seems that the facts are evidence for the contrary proposition, that the tannages are fundamentally of the same nature.
In this country the fat tannages have been typified by the "Crown" and "Helvetia" leathers.
In the modern fat tannages drums are used to give the necessary mechanical working to the goods.
Such vegetable-chrome combinationtannages possess many of the properties of chrome leather.
The chrome tannage of butts for strapping and harness backs, and for motor butts and picking bands may be similar to that for chrome sole, but drum tannages are more common and the two-bath process is often used.
In the oiltannages the mechanical treatment is generally more vigorous, and the "drying" process is conducted at a much higher temperature, with the result that there is a vigorous oxidation of the oil.
The following table shows the amount of leather produced by different tannages of 100 pounds of hides: Pounds.
The percentage of tannin absorbed by the different methods of tannages appears in the following table: Hemlock 64.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "tannages" in a variety of sentences. We hope that you will now be able to make sentences using this word.
