AND HOW TO USE IT. 



103 



follows : — Apparatus required — (i) Two small, wide-necked bottles 

 (those in which chemists sell one ounce of Citrate of Iron and Quinine 

 are very suitable) ; (2) perfectly sound corks, accurately fitting the 

 bottles ; (3) 6 or 8 inches of narrow glass tubing ; (4) some shellac 

 varnish. By means of a cork-borer or a rat-tail file, a hole is to be 

 made through the centre of each cork, just large enough to grasp 

 tightly the glass tubing. With the aid of a spirit-lamp, the tube is 

 to be bent at right angles at each end, as shown in Fig. 2. The 



Fig. 2. 



C 



I 





^^<u 



two arms are not to be of equal length ; one should be about 

 I inch and the other about 2\ inches. These arms must now be 

 passed through the holes in the corks themselves, then made air- 

 tight by a liberal application of the shellac varnish. A notch 

 having been cut in the edge of the cork carrying the longest arm 

 of the glass tube, the apparatus shown in the figure is complete. 

 To use it, proceed as follows : — About three parts fill bottle A 

 with filtered ram-wafer, and to this transfer the sections to be 

 bleached. Into bottle B put a sufficient quantity of crystals of 

 chlorate of potash just to cover the bottom, and pour upon them 

 one drachm or so of strong Hydrochloric Acid. Fit in the corks, 

 taking care that the one carrying the long arm of the glass tube be 

 applied to the bottle containing the sections. Immediately, the 

 yellow vapour of chlorine (or, strictly speaking, of euchlorine) will 

 be observed to fill the bottle B, whence it will pass along the con- 

 necting tube into the water contained in A, and effectually and 

 safely bleach the sections. When the water becomes super-satu- 



