942 Wisconsin Academy of Sciences, Arts, and Letters . 
placer, the ingredients are introduced around the tube to a 
suitable height, the upper diaphragm put in its place, and 
menstruum poured on, the joint half filled with water and the lid 
inserted. The atmosphere of the bottle B communicates with 
that of A through the tube e. 
This form of percolator was mentioned by Procter (1849) in 
his article on ‘ 4 The oleoresinous ethereal extracts. ? ’ 
—-— 1849 
Mohr, Redwood and Procter’s Pharmacy, p. 270. 
Figure A is a glass adapter, which is selected of suitable size. 
The lower extremity of this is partially stopped with a cork cut 
as represented in F, A layer of coarsely pounded glass is put 
over the cork, and above this a layer of clean sand, thus form¬ 
ing a strainer for arresting the passage of the solid particles of 
material to be acted upon. The end of the adapter is fitted, 
by means of a perforated cork, into the mouth of a bottle. A 
glass tube, one end of which is drawn to a capillary opening, 
is also fixed in the cork as shown at C so as to allow the air to 
escape out of the bottle as the liquid drops in. A piece of blad¬ 
der may be tied over the mouth of the vessel at A to prevent 
the evaporation of the solvent, but a few pin holes must be made 
in the bladder to admit of the ingress of air as the liquid passes 
into the receiver below. 
