38 
periments were 4815 cbc. and 4960 cbc. The burette was 
Mohr’s modification, for which a table of calibration had 
been constructed by weighing and interpolating in the ordi- 
nary way. 
The fact that the various meteorological changes influence 
to such a remarkable extent the nature and amount of the gases 
dissolved in sea-water renders it necessary, in any investiga- 
tion on the constitution of the atmosphere over the sea, to 
take particular account of these changes. Accordingly the 
temperature, pressure, and degree of humidity of the air ; 
direction and force (estimated — Beaufort’s system) of wind ; 
amount (estimated — overcast=10) and nature of clouds, and 
general appearance of the day, together with the temperature 
of the sea water and amount of sea disturbance (1 to 9), were 
noted at the time of each experiment. 
The following table shows the results of these observations, 
together with the amount, in volumes, of the carbonic acid 
in 10,000 volumes of air. All the experiments which were 
made are here given. The hours of observation, as before 
stated, were 4 a.m. and 4 p.m. 
