NO. 6 BODY RADIATION ALDRICH 3 



would have any influence under varying conditions of humidity and air 

 motion as well. Of course we are primarily interested in this as it affects the 

 normally clothed school child, but I feel that this study should be extended 

 to include adults as well, in order that we may make a definite contribution 

 to our knowledge concerning the relative importance of the different types 

 of heat loss under varying external conditions. 



(2) We are greatly interested in the' thermal heat gradients about pupils 

 normally clothed under conditions prevailing in the school rooms where the 

 average pupil is surrounded by his radiant neighbors, distance from him 20 

 to 24 inches. This matter should be studied at various temperatures ranging 

 fiom 60° to 70° F. and if the findings of the first study warrant it, under 

 various conditions of humidity and rates of air change as well. 



As a preliminary, in order to discover what criteria govern the 

 spacing of children in classrooms, the following letter, signed by the 

 Acting Secretary of the Smithsonian Institution, was sent in August, 

 1927, to the superintendents of schools in ten of the larger cities of the 

 United States : 



At the suggestion of the New York Commission on Ventilation, the Smith- 

 sonian Institution is conducting a research concerning the amount of body 

 heat loss by radiation, particularly as it affects children in the classroom. 



As an aid to this research, the Institution would greatly appreciate your 

 kindness in replying to the following three queries : 



(1) In the schools under your supervision, what considerations were factors 

 in establishing the space allotted to each individual in the classrooms? 



(2) In particular, was any consideration given to the loss of heat by radia- 

 tion from the individual pupils ? 



(3) Are the radiators or other artificial heat sources in classrooms shielded 

 to prevent direct radiation to the pupils ? 



Your cooperation is earnestly hoped for. 



Seven replies were received. To question (i), all seven answered 

 that the classrooms were of certain standard sizes, determined gener- 

 ally by state law. To question (2), all seven replied no. To ques- 

 tion (3), six answered no and one yes. This correspondence makes 

 it evident that as yet the question of radiation exchange between 

 pupils and surrounding objects has been given practically no consid- 

 eration in designing classrooms. 



DR. ABBOT'S EXPERIMENTS IN 1921 



In the spring of 1921, Dr. Abbot conducted a series of experiments 

 on the radiation from the nude body. This work was carried out at 

 the invitation of Dr. F. G. Benedict in the Nutrition Laboratory of 

 the Carnegie Institution in Boston. A description of this work and 

 summary of Dr. Abbot's results, since they have not been previously 

 published, are with his permission incorporated here. 



