SKETCH OF PROFESSOR COFFIN. 507 



ductions from the theory of the winds of the globe, which considers 

 them as due to the combined action of the movement produced in the 

 air by the greater heat of the equator, and the rotation of the earth on 

 its axis. 



The researches of Prof. Coffin also strikingly exhibit the fact of 

 the influence of the seasons in modifying the direction of the wind, or 

 in producing the results denominated monsoons. Thus, along the 

 eastern coast of North America, as is shown on the maps, the tendency 

 during the summer months of the opposing forces is to lessen the domi- 

 nant westerly wind, and this effect is noticed even beyond the Missis- 

 sippi, as well as in the Atlantic Ocean along our coast. The effect is, 

 undoubtedly, due to the change of temperature in the land the tem- 

 perature of the ocean remaining nearly the same during the year, while 

 that of the land is greatly increased in summer above the mean, and 

 depressed in winter. From this cause the air will tend to flow toward 

 the centre of the continent from the ocean in summer, and from the 

 same centre toward the ocean in winter. 



The results of the investigations of Prof. Coffin have been referred 

 to in all the treatises on meteorology which have appeared since their 

 publication, and they have been employed with other materials as the 

 basis of the wind-charts of the Atlantic and Pacific Oceans, prepared 

 and published by the English Board of Trade. 



In attentively studying the result of Prof. Coffin's labors, we can- 

 not but be struck with his conscientious regard for accuracy, and his 

 devotion to truth. In all cases in which the results do not conform to 

 the theory which explains the general phenomena, the discrepancies 

 are fully pointed out ; and, where he is unable to suggest an hypothet- 

 ical cause of the anomaly, he candidly acknowledges his ignorance. 

 In this respect he is an admirable example of a successful investigator, 

 since errors in science as frequently occur from defects of the heart as 

 from those of the head. 



After the publication of the work on the winds, he continued to 

 collect materials, at first with a view to an appendix, and finally ex- 

 tended his investigations to the winds of the entire globe. To aid in 

 this enterprise, the Smithsonian Institution placed in his hands all the 

 observations on the winds, which it had obtained from its numerous 

 observers during the twenty years since the system was commenced, 

 together with the observations made by the officers of the army, as 

 well as the extensive series of materials in the various series of trans- 

 actions of scientific societies of the Old World, obtained through the 

 exchanges of the Institution. This work, for several years past, Prof. 

 Coffin prosecuted with unremitting assiduity during all the intervals 

 which could be spared from his laborious professional duties. Un- 

 fortunately, however, he was not spared to complete the work, al- 

 though it is in such a condition as to be readily finished under the 

 direction of the principal assistant employed by Prof. Coffin. It is 



