VENETIAN CHALK 1059 



make it sticky ; it consists of sandarac, 250 parts; mastic, in tears, 64; resin, 125; 

 Venice turpentine, 250; alcohol, 1,000 parts by measure. 



Milk of Wax is a valuable varnish, which may be prepared as follows : Melt in a 

 porcelain capsule a certain quantity of white wax, and add to it, while in fusion, an 

 equal quantity of spirit of wine, of sp. gr. 0'830 ; stir the mixture, and pour it upon a 

 large porphyry slab. The granular mass is to be converted into a paste by the muller, 

 with the addition, from time to time, of a little alcohol ; and as soon as it appears to 

 be smooth and homogeneous, water is to be introduced in small quantities successively, 

 to the amount of four times the weight of the wax. This emulsion is to be then 

 passed through canvas, in order to separate such particles as may be imperfectly in- 

 corporated. The milk of wax, thus prepared, may be spread with a smooth brush 

 upon the surface of a painting, allowed to dry, and then fused by passing a hot iron 

 (salamander) over its surface. When cold, it is to be rubbed with a linen cloth to 

 bring out the lustre. 



Slack Japan is made by putting into the set-pot 48 Ibs. of Naples or any other of 

 the foreign asphaltums (except the Egyptian). As soon as it is melted, pour in 10 

 gallons of raw linseed oil ; keep a moderate fire, and fuse 8 Ibs. of dark gum 

 anime in the gum-pot ; mix it with 2 gallons of hot oil, and pour it into the set-pot. 

 Afterwards fuse 10 Ibs. of dark or sea amber in the 10-gallon iron-pot ; keep 

 stirring it while fusing ; and whenever it appears to be overheated, and rising too 

 high in the pot, lift it from the fire for a few minutes. When it .appears completely 

 fused, mix in 2 gallons of hot oil, and pour the mixture into the set-pot ; continue the 

 boiling for 3 hours longer, and during that time introduce the same quantity of driers 

 as before directed : draw out the fire, and let it remain until morning ; then boil it 

 until it rolls hard, as before directed : leave it to cool, and afterwards mix with 

 turpentine. 



Best Brunswick Black. In an iron pot, over a slow fire, boil 45 Ibs. of foreign 

 asphaltum for at least 6 hours ; and during the same time boil in another iron pot 

 6 gallons of oil which has been previously boiled. During the boiling of the 6 gallons 

 introduce 6 Ibs. of litharge gradually, and boil until it feels stringy between the 

 fingers ; then ladle or pour it into the pot containing the boiling asphaltum. Let the 

 mixture boil until, upon trial, it will roll into hard pills ; then let it cool, and mix it 

 with 25 gallons of turpentine, or until it is of a proper consistency. 



Iron-work Black. Put 48 Ibs. of foreign asphaltum into an iron pot, and boil 

 for 4 hours. During the first 2 hours introduce 7 Ibs. of red lead, 7 Ibs. of 

 litharge, 3 Ibs. of dried copperas, and 10 gallons of boiled oil ; add 1 eight-pound 

 run of dark gum, with 2 gallons of hot oil. After pouring the oil and gum, 

 continue the boiling 2 hours, or until it will roll into hard pills like japan. When 

 cool, thin it off with 30 gallons of turpentine, or until it is of a proper consis- 

 tency. This varnish is intended for blacking the iron-work of coaches and other 

 carriages, &c. 



A cheap Brunswick Black. Put 28 Ibs. of common black pitch, and 28 Ibs. of 

 common asphaltum made from gas-tar, into an iron pot; boil both for 8 or 10 hours, 

 which will evaporate the gas and moisture ; let it stand all night, and early next 

 morning, as soon as it boils, piit in 8 gallons of boiled oil ; then introduce, gradually, 

 10 Ibs. of red lead and 10 Ibs. of litharge, and boil for 3 hours, or until it will 

 roll very hard. When ready for mixing, introduce 20 gallons of turpentine, or more, 

 until of a proper consistency. This is intended for engineers, founders, ironmongers, 

 &c. It will dry in half an hour, or less, if properly boiled. 



VEGETABLE BUTTER. A fatty substance expressed from the seeds of an 

 Indian tree, the Bassia butyracea, Eoxb. It is said to make good soap. 



VEGETABLE ETHZOPS. A charcoal prepared by the incineration in a 

 covered crucible of the Fucus vesiculosus, or common sea-wrack. 



VEGETABLE FIBRE. Most of the useful vegetable fibres are described under 

 their proper heads, as FLAX, HEMP, &c. See also FIBRES, and FIBEE, VEGETABLE. 



VEGETABLE IVORY. See CoROSA NUTS, and IVOEY, VEGETABLE. 



VEGETABLE PARCHMENT. See PARCHMENT, VEGETABLE. 



VEIN'S (Filons, Fr. ; Gange, Ger.) sre the fissures or rents in rocks, which are 

 filled with peculiar mineral substances, most commonly metallic ores. See MIXES, 

 MINING, &c. 



VEIN-STONES are the mineral substances which accompany, and frequently 

 enclose, the metallic ores. See MINES, MINING, &c. 



VELLU1VT is a fine sort of parchment. See PARCHMENT. 



VELVET ( Velours, Fr. ; Sammet, Ger.). A peculiar stuff, the nature of which is 

 explained under FUSTIAN and TEXTILE FABRICS. 



VENETIAN CHALK, is STEATITE. 



3 Y 2 



