Colour and colour printing as applied to lithography : containing an introduction to the study of colour, an account of the general and special qualities of pigments employed, their manufacture into printing inks, and the principles involved in their application / by W.D. Richmond.

  • Richmond, W. D.
Date:
[1885?]
Catalogue details

Licence: Public Domain Mark

Credit: Colour and colour printing as applied to lithography : containing an introduction to the study of colour, an account of the general and special qualities of pigments employed, their manufacture into printing inks, and the principles involved in their application / by W.D. Richmond. Source: Wellcome Collection.

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    to make it smooth and taut. The surface is next covered with a patent elastic transfer-composition, suppHed by the maker, and which is then dried. The impression is now pulled upon it in re-transfer ink, the frame being removed from the machine in order to admit of this being done. It is afterwards replaced upon the machine, and then, by turning the handle, brought to the desired size, and fixed in position. It is finally taken off the machine, placed upon the stone, and transferred by one pull through. Supposing a reduction is wanted, the indiarubber is placed upon the machine and slightly stretched as before. Two dots may then be placed upon it to indicate the size to which the subject is to be reduced. The rubber is then stretched until these two dots are separated far enough to represent the corresponding actual dimension of the sub- ject. The frame being taken off the machine, an impres- sion is pulled upon it rather bare of ink, and, being returned to the machine, the indiarubber is slackened until the reduced size is arrived at. It is then fixed in that position, and the frame removed for the re-transfer. When an alteration in proportion is required, the handle is turned, and the subject equally altered until_ one dimen- sion is arrived at. The proper wheel is then disconnected, and the alteration made in one direction only. _ By an ingenious arrangement of helical springs in con- nexion with the hooks holding the rubber, their proper sliding upon the bars is accurately insured, thus obviating a serious defect in many previous contrivances. We may add, that the agency for this country has been placed in the hands of Messrs. Benjamin Winstone & Son, of I CO, Shoe-lane, London. Pieper's Precision-Pantograph. 305. Carl Pieper's Precision-Pantograph is based upon the same general principles that underlie the con- struction of the one just described, but it varies in details, and is supplemented by a special press which, doubtless, adds much to its efficiency, and enables wood-blocks and other type-high surfaces to be readily brought under its action. In connexion with it there are also two wood