--------+----------+--------------+------------------------
April 2 | 743.5 | 28.86 | Cloudy, snow on ground.
" 5 | 743.5 | 28.97 | " " " "
" 6 | 735 | 28.61 | Snowing.
" 7 | 744.5 | 28.63 | Clear, snow on ground.
" 8 | 748 | 27.59 | " thawing.
" 9 | 747.5 | 28.10 | " "
" 12 | 744 | 28.04 | Cloudy.
" 13 | 744 | 28.10 | Clear.
" 14 | 743.5 | 28.98 | "
" 15 | 750.5 | 28.17 | Raining.
" 19 | 748 | 28.09 | Clear.
" 20 | 746 | 27.72 | "
" 21 | 746 | 28.16 | "
" 22 | 741.5 | 27.92 | "
" 23 | 740 | 28.12 | "
" 24 | 738.5 | 28.15 | "
" 25 | 738.5 | 27.46 | "
" 28 | 738 | 27.34 | "
--------+----------+--------------+------------------------

The average number of volumes of carbonic acid in 100,000 volumes of
air is 28.16, the maximum number is 28.98, and the minimum 27.34.
These results agree with estimations made within the last ten or
fifteen years. Reiset[2] made a great number of estimations from
September 9, 1872, to August 20, 1873, the average of which is 29.42.
Six years later[3] he made many estimations from June to November, the
average of which is 29.78. The average of Schultze's[4] estimations is
29 2. The results of estimations of carbonic acid in the air, made
under the supervision of Munz and Aubin[5] in October, November, and