279 
1895-96.1 Dr J. Halm on the Temperature of the Air. 
and for both countries. For the same interval, extending from 
1882 to 1893, we have drawn the inverted curve of sun spots. 
The agreement between the two curves may be considered as 
perfect. There are a good many stations the observations of which 
extend over more than 100 years. They afford a large field for 
research, on the probability of secular variations of solar heat and 
other important questions in connection therewith. 
It is necessary for me to conclude this paper with a mere 
mention of some other consequences of our theory, which con- 
tribute to the solution of the question, so important in practical 
meteorology, how to determine the corrections for reducing single 
observations to the true arithmetic mean of the day. I may say 
that these corrections can be derived directly from the above-men- 
tioned tables for a , without referring to normal places, as was 
hitherto the case. Nor will I dwell any longer on other interesting 
particulars respecting the daily curve thus theoretically deduced, as 
I have given a somewhat full account of several of them in the 
paper already published. 
I would desire to give expression to the hope that these re- 
searches, so imperfectly sketched in this paper, may induce meteor- 
ologists to undertake further investigations in this field of natural 
science. 
