634 POISONS : THEIR EFFECTS AND DETECTION. [§§ 8l0, 8 ll. 
Yellow Pigments :— 
Chrome Yellow may be a fairly pure chromate of lead, or it may be mixed with 
sulphates of lead, barium, and calcium. The pigment known as “ Cologne yellow ” 
consists of 25 parts of lead chromate, 15 of lead sulphate, and 60 of calcic sulphate. 
The easiest method of analysing chrome yellow is to extract with boiling hydro¬ 
chloric acid in the presence of alcohol, which dissolves the chromium as chloride, 
and leaves undissolved chloride of lead, sulphate of lead, and other substances in¬ 
soluble in C1H. Every grain of chromate of lead should yield 0-24 grain of oxide of 
chromium, and 0-4 grain of chloride of lead. 
Turner’s Yellow, Cassella Yellow, Patent Yellow, is an oxychloride of lead 
(PbCl 2 7PbO), extremely fusible. 
Dutch Pink sometimes contains white lead. 
j Red Pigments :— 
Chrome Red is a bichromate of lead. 
Red Lead or Minium is the reel oxide of lead. 
Orange Red is an oxide prepared by calcining the carbonate. 
The chief preparations of lead which may be met with in the arts, in addition to 
the oxides and the carbonate, are— 
The Nitrate Of Lead, much used in calico-printing. 
The Pyrolignite of Lead is an impure acetate used in dyeing. 
The Sulphate Of Lead is a by-product in the prej^aration of acetate of aluminium 
for dyeing. 
The alloys containing lead are extremely numerous ; but, according to the ex¬ 
periments of Knapp, 1 the small quantity of lead in those used for household purposes 
has no hygienic importance. 
§ 810. Statistics of Lead-Poisoning. —During the five years ending 
December 1916, 6 persons died from the effects of lead ; 3 of these 
were accidental, the other 3 suicidal. 
§ 811. Lead as a Poison. —All the compounds of lead are said to be 
poisonous ; but this statement cannot be regarded as entirely correct, 
for the sulphocyanide has been proved by experiment not to be so, 2 
and the sulphide is also probably inactive. In the treatment of cases 
of lead-poisoning, the flowers of sulphur given internally appear to be 
successful. 3 
Lead-poisoning, either in its obscure form (producing uric acid in 
the blood, and, as a consequence, indigestion and other evils), or in the 
acute form (as lead colic and various nervous affections), is most frequent 
among those who are habitually exposed to the influence of the metal in 
its different preparations, viz. workers of lead, house-painters, artists, 
gilders, workers of arsenic, workers of gold, calico-printers, colourists, 
type-founders,' type-setters, shot-founders, potters, faience makers, 
braziers, and many others. 4 In white-lead factories, so large a number 
1 Dingl. Polytech. Journ., ccxx. 44G-453. 
2 Eulenberg, Gewerbe Hygiene, p. 712. 
3 Mohr’s Toxicologic, p. 78. 
4 The attention which the use of lead in the arts has always excited is evident 
f 10111 fact that one of the oldest works on trade hygiene (by Stockhausen) is 
entitled, I)e lithargyrii fumo noxio morbifico ejusque metallico frequentiori morbo vulgo 
dicto hiittenkatze, Gaslar, 1556. 
