Tue Microscope. 19 
ing” may here finda place: gum arabic; Venetian red; French 
chalk, or soapstone; Silesia blue; chrome yellow; Prussian 
blue; turmeric ; burnt umber; yellow ochre; drop black. 
Thé Silesia blue consists of a mixture of Prussian blue and 
barytes. In the sample examined asmall amount of lead (prob- 
ably there as white lead) was detected. The “ drop-black” is 
ground bone-black. The other names require no explanation. 
Of these colors only chrome yellow (chromate of lead) is per se 
poisonous. The ochres, however, are sometimes the product of 
the weathering and decomposition of pyrites containing arsenic 
or copper, and these elements can frequently be detected in 
them. In the colors examined, only the burnt umber showed 
arsenic; still in consequence of careless handling, poisonous 
materials sometimes get mixed with the substances used. 
The use of colors containing poisons for ‘“ painting” coffee 
has been forbidden, and toa large extent stopped by the prompt 
action of the Health Department of New York and Brooklyn. 
Although the aggregate number of pounds of coffee thus treated 
is no doubt very large, the proportion of the entire amount of 
coffee sold has been small, and in cases of “ painting,’ as has 
been seen, but few of the colors have poisonous constituents. 
Nevertheless, so long as buyers of raw coffee follow the older 
traditions, depending upon color as their guide, and 
‘*Do not care for dirty greens 
By any means,”’ 
or the reverse, some encouragement is given to these practices 
in defiance of the law, and only the enlightenment of the buy- 
ers to suit the changed conditions of the coffee-trade can effect- 
ually stop “painting.” At the present time the most expert 
buyers depend very little upon color, but judge of the samples 
by the appearance and aroma of the roasted beans, and the fla- 
vor of the infusion. 
The coloring of vermicelli with chrome yellow seems te 
have come about inthis wise: A large portion of our population, 
chiefly Germans, are very fond of what they term “ Eier Nu- 
deln,” a yellow vermicelli, the color being supposed to be im- 
parted by the admixture of eggs with the flour used in 
the manufacture. Some unscrupulous manufacturers, having 
