REPORT OF THE SECRETARY.' 23 



it could be carried on and completed, with due reference to the state of 

 its finances. This committee met at the Institution and carefully con- 

 sidered the whole subject, with the manuscripts before them, and con- 

 cluded that a new edition of the rain-fall tables should be completed as 

 soon as possible, this being a subject of great interest, both theoretically 

 and in its practical applications. An allowance was therefore made for 

 the completion of this work, and it will be ready for the press during the 

 present year. The publication of this new edition of the rain-fall tables 

 will be commenced and completed as soon as practicable. The baro- 

 metrical reductions, the digest of the periodical phenomena of animal 

 and vegetable life, &c, will be prosecuted as rapidly as the funds of the 

 Institution will warrant. 



It is, of course, unnecessary to refer to the fact that active operations 

 in regard to meteorological observations, in accordance with the policy 

 of Professor Henry have been transferred to the Weather Bureau of the 

 Signal Department of the United States Army, under the care of General 

 A. J. Myer, and that hereafter the meteorological expenditures will be 

 confined to completing the presentation of the results obtained during the 

 twenty-five years of the active work of the Institution in that direction. 



RESEARCHES. 



The appropriation made to Dr. H. C. Wood, jr. in 1870 and 1877 for 

 experiments to determine the nature and cause of the increased tempera- 

 ture of the body during fever has been expended and a report of the 

 investigations is being prepared for publication by the Institution. A 

 brief abstract of this memoir will be found in the appendix to this 

 report. 



The first point to be determined was whether fever was as complex 

 as it appears, or whether there be not some dominant symptom charac- 

 teristic of the process. By artificially heating living animals, generally 

 and locally, it was found that elevation of the bodily temperature is 

 sufficient to produce all the nervous and circulatory symptoms of fever 

 and that the cooling of the heated part is capable of removing the 

 symptoms, so that fever may be defined to be a morbid process which 

 produces elevation of the bodily temperature. 



The next point was to determine whether the increase of the bodily 

 temperature in fever was due to an increase of the amount of heat pro- 

 duced, or to the failure of the body to throw off its heat. 'For this pur- 

 pose the laws governing the production and loss of animal heat in health 

 were studied by means of calorimetric and cardiometric observations on 

 animals under various conditions, and it was determined that there is in 

 the cortical region a nerve-center which controls the production of animal 

 heat. 



The subject of fever itself was then investigated. The experiments 

 were mostly made upon dogs, each experiment continuing for from three 

 to six days. Thermometrical readings were made every twenty minutes 



