82 REPORT ON THE STATE CABINET. 



cold, in its normal course, and as it would always blow if there were 

 no mountain ranges or other disturbing causes to divert it from its 

 proper path. 



So with '' heated terms II'' &% they have been called. So far as I have 

 been able to observe and collect statistics, they occur as follows: First. 

 We have a balancing of winds, or air currents, so that over a large 

 tract, a hundred miles or more in diameter, there are no winds, except 

 slight local currents not passing out of this region, and none from without 

 it passing in. Second. We have a clear sky, with very little vapor or 

 other substance in the air " to absorb," or rather, as I would say " to 

 reflect back " the sun's rays. These conditions, continuing for a day or 

 two, will produce great heat. If the air continues clear and dry, the heat 

 becomes great, and the direct rays of the sun seem to be intensely scorching. 

 But for the most part, as a third condition, there will arise, by evapora- 

 tion, within this enclosure of the winds, moisture enough to overspread 

 it like a dome (not perhaps with visible clouds); and thus, Avhile it does 

 not obstruct the sun's rays from passing through to the earth, it absorbs 

 and reflects back all of those that are radiated from the earth, and 

 constitutes an oven-like enclosure, with the walls of wind for its sides 

 and this mass of vapor for a dome ; and the weather is not only hot, but 

 sultry. 



I have said there is in such cases much moisture in the air. This 

 usually shows itself, in time, in clouds and a low dew point. But it is a 

 mistake to suppose that when there are no clouds tliere is but little 

 moisture, or rather water, in the air. Clouds are merely vapor made 

 visible or manifest by contrast of temperature. When the ascending 

 vapor, which is in fact always ascending in some quantity, even in the 

 coldest of weather, reaches a current or stratum of air enough colder 

 than that in which it first became vapor, it is converted into a cloud. 

 This may occur simply by the vapor's ascending to an elevation approach- 

 ing what is called the snow line ; but clouds are formed for the most 

 part at the place where the two currents meet, blowing of course in 

 opposite directions, the upper one being generally the coldest. 



Nor can we doubt for a moment that the meteorological records of any 

 place, if accurately kept and published in detail, would furnish data 

 from which other and most important inferences could be drawn ; and as 

 illustrating several such points, and as a slight contribution to our 

 knowledge on local climatology, I give in a tabular form the average 



