Category: Engineering & Technology
The two first are used in the liquid state, the chalk, however, in solid form. The ink can be obtained in a liquid form and the two others in solid state. All three materials consist principally of soap, tallow, wax, resin, and soot. Soap and tallow give the necessary grease,...
The half-tone process is used in photo-lithography to reproduce originals which do not contain distinct lines or points, but closed tones, which are executed either in one or se...
2. CHAPTER I.By photo-lithography we generally understand that process by which it is possible to prepare a printing plate or a stone by the aid of photography from any original, whether it...
3. CHAPTER II.The arrangement of the reproduction studio is essentially different to that for ordinary portrait work. The general points of such arrangements are described in detail in the ha...
4. CHAPTER III.Photo-lithographic or gelatine papers are articles of commerce and entirely fulfil their purpose, and must before use be sensitized in a bichromate bath. In establishments where...
1. Chapter IV.The two first are used in the liquid state, the chalk, however, in solid form. The ink can be obtained in a liquid form and the two others in solid state. All three materials co...
5. CHAPTER IV.The processes of photo-lithography previously described are based upon the printing on to bichromated gelatine or albumen paper development with a greasy ink and subsequent tran...