176 
and the relative moisture 60°, showing that the air contained 
0-7 grains of moisture in a cubic foot. The total quan- 
tity which air at 18° F. can contain is 1*2 grains, whereas 
at 60° F., the temperature of my room, it could contain 5*8 
grains; so that air entering with only 07 grains would 
have only 12 relative humidity, but as there is always 
evaporation going on in my room from the water basin, &c., 
and also some steam entering from the steam stove which 
heats the room, the percentage of moisture is raised, and on 
the occasion referred to the amount actually in my room 
was 27 rel. humid. 
Dr. Volland* made some observations on the amount of 
moisture in the room, and he obtained much more than I 
have ever found the case, but it seems to me that this is 
to be accounted for by his using the wet and dry bulb 
thermometers, which I find are not at all suitable for room 
observations, as the stagnation of air is too great. I have 
found that the temperature of the wet bulb is reduced 
several degrees by the artificial current produced by waving 
a newspaper in front of it. 
On the Riviera di Levante I dare not sleep with an open 
window, which is easily understood, because the relative 
moisture being more at night than in the day, without the 
temperature outside being very materially below that of the 
room, we should only be breathing damp air through the 
night. We now see that in Davos we are not only breath- 
ing an absolutely dry air, but also nearly, or all through the 
24 hours, a relatively very dry one, in fact, drier than either 
on the Riviera or Egypt. 
Seeing how dry the rooms really are we can easily 
understand how it is that the general public should form 
very exaggerated ideas as to the dryness of the place, for 
even the shopkeepers when they have spoiled old stock try 
to pass it off by ascribing the changes that have taken place 
# Ueber Verdunstung und Insolation, von Dr. Volland. Basel, 1879. 
