Oil Colours and Printers' Inks; A Practical Handbook Treating of Linseed Oil, Boiled Oil, Paints, Artists' Colours, Lampblack and Printers' Inks, Blac (Paperback)

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1903 edition. Excerpt: ...the flaky form of the pigment is lost, and it takes the shape of grains which require much longer rubbing up with boiled oil to produce a uniform mass. The flaky lampblack on the other hand mixes with the oil easily and rapidly. For the ignition of lampblack boxes of sheet iron are used, painted outside to protect the metal from the fill. This painting is beat done with an ordinary plaster of loam and hair. The loam is stirred up with water to a very thin paste, which is painted uniformly over the outside of the iron box with a brush, repeating the application several times, but never applying another coat till the last is dry. When this is finished, several more coats are applied, the loam being this time mixed with chopped tow or cowhair. This is repeated until the total thickness of the coating is several mm. Such a coating, carefully laid on sticks very close, enables the boxes to be used for a very long time, while unprotected ones are quickly burnt through. Very special care must be used with the boxes. Their bottoms should be coated with loam, and the covers must fit accurately and the join must be caulked with loam while the box is in use. The lampblack must be rammed into the boxes to a solid mass. A very small hole is made in the cover to allow of the escape of the volatile bodies. When the boxes are placed in the furnace, they are gradually heated, applying the heat first at one end. The temperature is gradually raised, and extended over the rest of the box. Finally a bright red heat is reached at which the box is kept for half an hour. This treatment drives off the volatile matters almost entirely and gives the lampblack its proper black colour. As above stated the greatest care must be taken to protect the lampblack from the air...