THE ANALYSIS OF BUTTER 69 



through muslin and ignited, and 400.0. of sulphuric 

 acid solution (see Appendix) ; attach the flask by 

 means of a cork to a bulb tube attached to a condenser, 

 the dimensions of which are {riven in the sketch 



FIG. 34. Caustic Soda Apparatus. 



(Fig. 35). Support the flask on a piece of asbestos card 

 in which is cut a hole 5 c.m. in diameter and heat with 

 a very small flame, till the fatty acids float in a clear 

 layer on the surface of the liquid ; then turn up the 

 flame to such a height that no c.c. distil in from eighteen 

 to twenty-two minutes. Collect no c.c. ; turn out the 



