Читать книгу Glue, Gelatine, Animal Charcoal, Phosphorous, Cements, Pastes and Mucilages - F. Dawidowsky - Страница 10

Table of Contents

The raw materials used for the manufacture of glue consist of a variety of animal offal. The principal substances employed are refuse from tanyards, such as scraps of ox and other thick hides, the waste of the workshops of leather dressers, morocco leather manufacturers, etc. The tendons and intestines of many animals, rabbit and hare skins deprived of their fur, cat and dog skins, scraps of parchment, waste of turners and button makers, and offal from butcher shops and households, help to swell the series of materials used for the manufacture of glue.

The materials are collected and sold either directly to the glue boiler, or to dealers making a specialty of glue stock.

As a thorough knowledge of these waste products is of importance to the manufacturer, this chapter will be devoted to their detailed description, the success of the enterprise depending largely on the selection of the raw materials and their careful sorting and preparation. By bearing in mind the varied products—from the most ordinary black glue to the colorless glassy gelatine for photographic and culinary purposes—it will be understood that entirely different raw materials have to be employed for the finer products than for the ordinary qualities of glue.

According to their derivation the raw materials may be divided into three groups, namely:

1. Skin-like raw materials: Skin, leather, tissues.

2. Bone raw materials.

3. Materials obtained from fishes: Air bladders, scales, etc.