102 REPORT OF THE CHEMIST OF 



IV. — SUNSHINE TEMPERATUKE. 



The meteorologist seeks to find the temperature of the air in the shade, 

 removed as far as possible from the direct influence of the sun's rays, and 

 for this purpose much ingenuity is exercised to estimate as far as possible 

 the direct heat rays of the sun. For the meteorologist such a method is- 

 very valuable. We have so long dwelt upon this shade temperature as the 

 most important datum in the thermometry of physical existence that we 

 forget the more important fact of the sunshine temperature. For the liv- 

 ing thing, whether animal or vegetable, the sunshine temperature is even 

 more important than that in the shade. Vigor in living is the child of the 

 sunshine. " Walk in the light " is the condition of excellence alike in the 

 physical and in the moral world. In the vegetable kingdom the importance 

 of direct sunlight is fully recognized. Other things being equal, the vigor 

 and development of the plant is directly proportionate to the amount and 

 intensity of the sunlight. Our grains, our fruits, and all our farm products 

 are packed full of sunshine. No shade temperature can compare in im- 

 portance with this sunshine temperature. Why, then, should observations 

 by the thermometer be limited to the shade? Can the conditions of vege- 

 table growth be properly studied without a full and complete study of the 

 thermometry and psychrometry of the sunshine as well as the shade? 



Some observations looking in this direction have been taken during the 

 year, but they are imperfect and unsatisfactory as all such observations must 

 be when better methods and more complete results are readily obtainable. 

 These observations relate to the maximum and minimum temperatures 

 taken in open air and with full exposure to the sun. Two sun ther- 

 mometers in vacuum were used, one with bright or mercurial bulb and the 

 other blackened by coating of lampblack. These were actinometers rather 

 than thermometers. Two other self-recording thermometers with bulbs of 

 black glass were used, one at the College, the other at Grayling. All of these 

 thermometers were placed ten inches above the ground, and results read off 

 daily. A minimum thermometer, placed four inches above the ground, was 

 used at each station from April to November. 



No discussion of the results of these observations is attempted, A fuller 

 set of observations of the temperature of wet and dry bulb thermometers 

 in the sunshine, as well as the maxima'and minima of temperatures in the 

 same way will be made next year, and some discussion of these fuller obser- 

 vations will then be attempted. The observations as taken this year are 

 given in the following tables : 



