PHILOSOPHICAL SOCIETY OF WASHINGTON. 63 



The election of Mr. Edward Goodpellow, of the U. S. Coast 

 Survey, as a member of the Society was announced. 



Mr. J. A. Osborne exhibited and described 



A NEW METEOROLOGICAL INSTRUMENT. 

 (ABSTKACT.) 



A consideration of the effect of climate upon animal life and 

 "Well-being will lead to the conclusion that the chief influence 

 which the elements exert upon the human body is essentially 

 thermic in its character. The tendency of the actual temperature 

 of the atmosphere, its humidity and motion, as well as that of 

 the direct radiant heat from the sun, is to effect a change in the 

 normal warmth of the body. 



No attempt has hitherto been made to give definite expression 

 to the physio-thermic influence for different places on the surface 

 of the earth, or for the same place at different times. The in- 

 strument exhibited for this purpose consists of an isolated cylin- 

 der of bank-note paper, hanging from a horizontal ring, and con- 

 taining about three pounds of water raised to the temperature 

 of the blood. A thermometer is suspended in the water, and, as 

 the latter cools spontaneously, it is kept in continuous and perfect 

 agitation by clock-work, so that a true determination of the tem- 

 perature of the whole mass is constantly indicated. By recording 

 in seconds the time in which the mercury sinks from degree to 

 degree, we obtain a series, which, being reduced to a single ex- 

 pression, will give a number comparable with the loss of heat 

 sustained by a human being, and proportional to other observa- 

 tions made with the same or a similar instrument. For it will 

 be seen that the cylinder and its contents, having a surface 

 which is slightly moist, is subject to the same influences which 

 affect a man in the same locality ; and its loss of temperature is 

 determined by the combined action of radiation, evaporation, 

 and the convection of its heat by the moving currents of air. 



As an animal has to maintain a constant temperature, losing 

 as much heat as he makes, an investigation of the external 

 causes which determine that loss, or tend to retard it, is of pre- 

 eminent importance. 



Having obtained a serviceable value for the aggregate physio- 

 thermic influence, it was proposed, by the simultaneous use of 

 pervious and impervious cylinders, placed in and out of the wind, 

 to analyze this total, and apportion to each of the great factors 

 its proper share in the production of sensible heat or cold. And,, 

 finally, by an investigation of many such analyses, to establish. 

 an empirical formula by the aid of which existing meteorological 

 records may be expressed in units of thermic value ; thereby, in 

 the interests of physiology, to extend a knowledge of the climatea 

 of the globe, subjectively considered. 



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