MISCELLANEA. 
1 77 
This powder has various uses; it is used as a paint, and to 
make thumb and button blue for the laundress ; it is used 
to colour confectionery, and by the Chinese, whom the 
Europeans have learned to imitate, to make green tea. But 
its principal use is in calico-printing. When used for the 
latter purpose, however, the prussian blue is usually made in 
the cloth itself. If we thicken a solution of green copperas 
with gum or flour, and print a particular pattern upon a piece 
of cotton, and then pass it through a bath of the yellow salt 
dissolved in water, we then obtain the pattern in prussian 
blue so much admired by ladies. In general, the beautiful 
dark blue dresses, with white patterns, are made by covering 
the whole of the calico with prussian blue, printing the pat- 
tern upon it with caustic soda, or potash, thickened with 
pipe-clay. The caustic substance decomposes the prussian 
blue, leaving the iron in the cloth as a buff pattern ; but, by 
washing in a bath of oxalic acid, the iron is removed, and the 
pattern remains of a beautiful white. Thus may worthless 
woollen rags, and similar vile things, come back again to us ; 
at one time in our tea, while they may have assisted to make 
the spoon with which it is stirred ; at another as a brilliant- 
coloured flower upon our room papers; or, finally, as the 
colouring material of a lady’s dress.” 
MONGOLIAN CUSTOM. 
When the Mongolian army proceeds on service, a body of 
men is sent two days’ march in advance, and parties are sta- 
tioned upon each flank in the rear, in order to prevent its 
being attacked by surprise. When the service is distant, they 
carry but little with them, and that chiefly wdiat is requisite 
for their encampment, and vessels for cooking. They subsist, 
for the most part, on milk. Each man has, on an average, 
eighteen horses and mares, and when that on which they ride 
is fatigued, they change it for another. Should circumstances 
render it necessary, in the execution of a duty that requires 
dispatch, they can march for ten days together without 
dressing victuals; during which time they subsist on the 
blood drawn from their horses, each man opening a vein and 
drinking from his own animal. They make provision, also, 
of milk, thickened and dried to the state of a hard paste or 
curd . — Marco Polos Narrative. 
XXIX. 
23 
