NUTRITION — MENDEL. 209 



air-motions when the horizontal motions are given. These methods have 

 been tried practically in a number of cases by constructing maps of the 

 vertical air-motions derived from observations of the wind given on the 

 common weather maps, and in this way the vertical motions sufficiently near 

 the earth's surface are obtained with great ease. To obtain the vertical 

 motions in the higher strata, observations obtained by kites and balloons, in 

 connection with the observation of the motion of the clouds, will have to be 

 used, but as yet it can not be stated whether sufficient observations for deriv- 

 ing vertical motion can be obtained by this method. This will be made the 

 subject of further investigation. 



The method stated can also be used for the investigation of the vertical 

 motions on the sea, if observations of the horizontal motions are at hand; 

 but lack of such observations renders the use of the method for oceano- 

 graphic purposes very limited at present. 



Some work complementary to the investigation of the statics of the sea 

 has been performed, especially a recalculation of the hydrographic tables, 

 using Dr. Ekman's new determination of the compressibility of sea-water. 

 The work of drawing a topographical map of the world, for use in investiga- 

 tions relating to the dynamics of the atmosphere and the sea, has also been 

 continued. 



NUTRITION. 



Mendel, Lafayette B., Yale University, New Haven, Connecticut. Grant 



No- 265. Study of the physiology of growth, especially in its chemical 

 processes. (For previous reports see Year Books Nos. 4, 5, and 6.) 



$2,000. 



The investigations on the physiology of growth which have been facili- 

 tated by this grant have been published in a series of papers reported in the 

 bibliography on pp. 45-52. They indicate that the equipment of the growing 

 or developing animal organism for its physiological work is in various 

 respects different from that of the adult. This applies especially to the dis- 

 tribution and richness in enzymes and is well illustrated in the case of purine- 

 converting enzymes (see Chemical Studies on Growth, II). The synthetic 

 capacity of the embryonic tissues has also been emphasized (e. g., in Chemi- 

 cal Studies on Growth, VI). 



The study of the influence of diet on the chemical composition of the body 

 clearly emphasizes the attempt of the animal organism to maintain a fixity 

 in its fundamental tissues. The fat and water content of the body tend to 

 vary in inverse relation. High fat-content is accompanied by low water- 

 content. But aside from the deposition of fat it is practically impossible. 

 by alimentary methods, to alter the fundamental composition of the active 



