PRACTICAL AGRICULTURAL CHEMISTRY [10-11 



Bore two holes through the cork, as described in para- 

 graph 8. Next bend a piece of glass tube at an angle of 

 i2o°, as shown in fig. 10 (6), taking care that the ends of the 

 tube are rounded (paragraph 5). Force one end just 

 through the cork. Now bend another piece of glass tube 

 at an angle of 6o° (a) and pass it through the second hole 

 in the cork, so as to nearly touch the bottom of the flask. 

 If the tubes have been carefully adjusted they will fit 

 tightly into the cork, so that when the cork is placed in the 

 neck of the flask, and one tube is closed with the finger, no 

 <^ air should escape when air is blown 

 into the flask from the mouth by 

 means of the other tube. 



Upon the end of the larger 

 tube (a) a small piece of rubber 

 tubing is placed, into which is pushed 

 a short piece of glass tube drawn 

 out into a jet (c). 



Now fill the flask with distilled 

 water. It may either be used for 

 propelling a fine jet of water through 

 the jet (c) by blowing into the larger 

 tube (b), or a larger stream may be 

 obtained by inverting the bottle and pouring out of the 

 tube (6). If hot water is required the flask may be placed 

 on wire gauze on a tripod stand, and the contents of the flask 

 heated over the Bunsen flame. 



A rubber cork may be substituted for the wooden one, 

 and will be found to last much longer. 



II. Solution. — Most solid substances dissolve in some 

 kind of liquid. Water is the most common solvent. The 

 amour, t dissolved varies according to circumstances ; hence 

 some substances are very soluble, others less so, and some 

 only slightly soluble. 



Solution usually takes place most rapidly when the 



Fig. 10 



