1820.] Scientific Intelligence. 469 



This I ascribe to oxygen which the rosin contained. Henca 

 it follows that a grain of rosin is composed of the following con- 

 stituents : 



Carbon 0-6324 



Hydrogen 0-1164 



Oxygen 0-2512 



1-0000 



Now if we convert these respective weights into volumes, we 

 shall find them as follows : 



Carbon 5 cubic inches 



Hydrogen 6-i- 



Oxygen 0-75 



Now a volume of carbon and hydrogen is equivalent to an atom, 

 and half a volume of oxygen is equivalent to an atom. Of con- 

 sequence the constituents of common rosin in atoms are as 

 follows : 



5 atoms carbon = 3-7500 



5-k- atoms hydrogen = 0-6875 



' 1^ atom oxygen = 1-5000 



6-9375 



Or, doubUng each constituent to get rid of the half atoms, we 

 obtain 



10 atoms carbon = 7-500 



11 atoms hydrogen = 1-375 



3 atoms oxygen = 3-000 



11-875 



Rosin kept for some time in a state of fusion at the tempera- 

 ture of 276° was subjected to analysis in the same way. 



I obtained 4-049 cubic inches carbonic acid = 0-518 gr. carb. 

 Water, 0-2 gr = 0-022 gr. hyd. 



0-540 



Loss = 0-460 



This loss I ascribe to oxygen. 



These quantities converted into volumes become : 



Carbon 4 cubic inches. 



Hydrogen 1 



Oxygen li 



This is equivalent to 



4 atoms carbon. . . = 3-000 or 8 atoms carbon. . . = 6-00 

 1 atom hydrogen . . = 0-125 2 atoms hydrogen . = 0-25 

 3 atoms oxygen . . = 3-000 6 atoms oxygen. . . = 6-00 



6- 125 12-26 



