Co-ordination of Subjects 39 



being can live in a boiling-point temperature if the air is dry, but he 

 cannot live in anywhere near so high a temperature if there is moisture. 



The entire understanding of the working of the ear is a matter of 

 physics, in that "sound" is a branch of that science. And, as the larynx 

 is the instrument through which our vocal sounds are produced, this, 

 too, must be studied in the light of physics. 



All knowledge of the eye, such as our ability to fit glasses, opera- 

 tions for ocular defects, and all the instruments with which the modern 

 oculist examines and remedies eye-troubles, are the result of direct 

 applications of the principles of "light," which, like "sound," is a branch 

 of physics. Any assistance in improving hearing or sight must, there- 

 fore, be looked for only in the laws of physics. 



The microscope, without which practically none of our modern 

 scientific work would be possible, is the direct application of the laws 

 found in physics, and there cannot be a single improvement in that 

 instrument until a new principle of physics is discovered. 



Likewise, the microtome, the instrument by which we are able to 

 cut minute sections for the microscope, could not cut with precision the 

 thin slices that it does (1/25,000 of an inch in thickness), if it were not 

 made in accordance with the laws of physics. 



Electricity, used so much now in the treatment of disease, the x-ray, 

 the fluoroscope, and radium — all these come under the science of 

 physics. 



That same science explains why the blood-platelets gather along 

 the blood-vessel where the blood stream is slowest; it explains how 

 coagulation is thus assisted so that we do not bleed to death when 

 wounded; it tells us. why one can crawl over thin ice when walking 

 across the same ice-sheet would be impossible ; why we can safely crawl 

 on the floor in a room filled with smoke, when standing erect would be 

 fatal; it makes an intelligent understanding possible of how to drain 

 wounds ; it tells us why water-pipes burst when the water in them 

 freezes; it tells us why a quilt or comforter of cotton is warmer than 

 a woolen blanket; it tells us why men's voices are different from those 

 of women's, and why the pupil of the eye can accommodate itself to 

 changing distances and intensity of light. And, just as it tells us that 

 an electric bell will not ring until the proper connection is made, so 

 it makes possible the locating of lesions in the body by noting where 

 nerve connections are functioning properly and where they are not. 



Probably the mathematical sciences may seem somewhat remote 

 from the study of life in general, yet calculus is needed in the study 

 of physical chemistry, and the laws of refraction in the fitting of glasses. 

 The relationships of structure in the body must be studied both as to 

 their quantity and quality. The various names given to the different 

 forms and shapes of the parts of the body are largely taken from 

 geometry. 



Surely so remote a subject as ancient Greek is far removed from 



