1853.] 



TEST-THERMOMETER FITTED. 



207 



After all this, I ask, who will dispute the power of a 

 Captain of one of Her Majesty's ships-of-war ? Noon 

 he has invariably controlled, eight A.M. and eight P.M. 

 also; but here the thermometers are compelled to con- 

 demn themselves or the mercury. 



With these matters fresh on my mind, I constructed 

 the mercurio-alcoholic thermometer D, being a glass-stem 



* If mercury freezes at 39, how is it that it continues to rise and 

 fall, in conformity with the spirit, between 3 9 and 46? 



