the Manufacturing of Verdigrise. 147 
them a plate of copper, and leaving it buried there for 
twenty-four hours. If the plate of copper, after this pe- 
riod, is found covered with a smooth green crust, in such 
a manner that none of the metal appears, they are then 
thought lit for being disposed in layers with the copper. 
On the other hand, if drops of water are observed on the 
surface of the plates, the plates are said to siveat , and it 
is concluded that the heat of the husks has not sufficiently 
subsided. They consequently defer making another trial 
till the next day. When they are assured that the husks 
are in a proper state, they form them into layers in the 
following manner : 
The plates are all put into a box, which, instead of 
having a bottom, is divided in the middle by a wooden 
grate. The plates disposed on this grate are so strongly 
heated by a chafing dish placed under them, that the wo- 
man employed in this labour is sometimes obliged to take 
them up with a cloth, in order that she may not burn her 
hands. As soon as they have acquired that heat, they 
are put into the jars in layers with the husks. Each jar 
is then closed with a covering of straw, and left to oxy- 
date. This period is called coua , to hatch. Thirty or 
forty pounds of copper, more or less according to the 
thickness of the plates, are put into each jar. At the end 
of ten, twelve, fifteen, or twenty days, the jar is opened ; 
and if the husks are white, it is time to take out the plates. 
The crystals are then seen detached, and of a silky ap- 
pearance on their surface. The husks are thrown back, 
and the plates are put in what is called relai. For that 
purpose they are immediately deposited in a corner of the 
cellar on sticks ranged on the floor. They are placed in 
an upright position, one leaning against the other ; and at 
the end of two or three days they .are moistened, by tak- 
ing them up in handfulls and immersing them in water in 
earthen pans. They are deposited quite wet in their for- 
