AmMJ°yu>r;sP78an"-}      Fluid  Extracts  by  Repercolation. 
241 
Scale,  one-sixth  of  the  actual  linear  size. 
because  the  quantity  of  substance  operated  upon  is  too  small.  Very 
good  and  uniform  results  need  hardly  be  looked  for  when  the  quantity 
operated  on  for  each  percolation  is  less  than  an  avoirdupois  pound. 
That  is  when  less  than  that  quantity  is  used,  great  care  and  skill  are 
necessary  to  get  good  results.  Another  percolator,  applying  the  same 
principles  by  the  same  details,  but  having  about  five  or  six  times  the 
capacity  of  the  first,  was  soon  after  made  and  put  into  use,  and  cuts 
of  these  two  percolators  are  shown  upon  this  and  the  opposite  page,  of 
their  relative  sizes,  both  upon  a  scale  of  one-sixth  of  the  actual  linear 
dimensions,  the  reference  letters  denoting  the  same  parts  in  both.  Of 
