838 THE POPULAR SCIENCE MONTHLY. 



ances in the equilibrium of temperature, whence follow ascend- 

 ing currents, cloud and rain. He spent much effort in trying to 

 secure an experimental demonstration of this scheme, and made 

 unsuccessful petitions to Congress and the Legislature of Penn- 

 sylvania for appropriations to enable him to carry them out on 

 an adequate scale. The scheme was not regarded as practicable, 

 and he became the object of some ridicule for his enthusiasm — to 

 which he replied in his book with the self-possession of a man 

 who believes to the full in his purposes : " Gentlemen have made 

 their puns on this project, and had their laugh : and I am sorry 

 to see, by letters which I have received, that my friends and rela- 

 tions at a distance are much troubled by these innocent laughs ; 

 but let them be consoled : I have laughed too, well knowing that 

 those who laughed the most heartily would be most willing to 

 encourage the experiment as soon as they discovered they had 

 nothing to laugh at. As a proof that I was right in this antici- 

 pation, I may be permitted to say that I have lately received a 

 letter from a highly distinguished member of the American 

 Legislature,* who laughed as heartily as any one when my peti- 

 tion was presented them, containing many kind expressions, and 

 promising me, by way of amends for his levity, to avail himself 

 of the earliest opportunity of being better informed on the sub- 

 ject of my new philosophy. Such conduct as this is all I want ; 

 I fear not the strictest scrutiny." The same confident spirit is 

 exhibited in his letter to his superior in the War Department, 

 suggesting a second year of employment in the official study of 

 storms, and which is given in fac-simile on the following page. 



In 1843 Prof. Espy was given a position in the War De- 

 partment, where he could pursue his investigations in atmos- 

 pheric currents and disturbances, and receive reports from dis- 

 tant points of observation. He instituted a service of daily 

 weather reports, out of which our present Signal-Service system 

 has grown ; and, on the basis of this enterprise, as Mrs. Morehead 

 relates in her book. Prof. Henry once remarked to her that 

 there was no question in his inind that " Prof. Espy should 

 be regarded as the father of the present Signal Service of the 

 United States, his ' Theory of Storms ' having led the way to its 

 establishment and present success." Prof. Henry added that the 

 charts now used in the service were identical (with some modi- 

 fications) with those that the " Old Storm King " constructed for 

 use in the Meteorological Bureau of the War Department when 

 he was at its head. A similar acknowledgment was made by 

 General Myer. Prof. Espy was for several years a regent of the 

 Smithsonian Institution, and was brought into close relations and 

 friendship with Prof. Henry. On the occasion of his death, Prof. 



* Hon. J. J. Crittenden. 



