222 C. M. Warren on the Volatile Hydrocarbons. 
representing more nearly the true boiling-point of the body. In 
stating my results, however, I shall give the limits of tempera 
ture within which the distillation was effected. The thermome- 
ters employed in the determinations were the best that I could 
obtain from Fastré of Paris; for the temperatures below 100° 
the instrument used was calibrated, and the scale divided into 
fifths of a degree. The determinations above 100° were all 
made with one thermometer. 
The method just described differs in some respects from that 
f Kopp. He objects to the practice of taking boiling-points 
with the thermometer bulb immersed in the liquid,” on the 
. 
in a majority of instances such wo 
el des T in die sie iissigkeit 
Sa bey : centre in die siedende Fliissigkei 
tauchen, 
as Ende des 
der auf diese 
welcher 
nthe 
sieden- 
