JUGGLING WITH LIFE 



quality of the blood remains unchanged to prove the 

 common origin. Blood is indeed thicker than water. 



GROWING ANIMAL TISSUES OUTSIDE THE BODY 



It has been observed that the remarkable fluid with 

 which Dr. Nuttall's wizard-like tests are made is de- 

 veloped in the body of an animal. I wish now to tell 

 of a series of experiments in which the process is 

 reversed, and tissues taken from the body are made 

 to grow in glass receptacles. 



When I add that the tissues that are thus cultivated 

 under glass have perhaps been cut from the body of a 

 dead chicken that has hung for some days in cold 

 storage, the reader will divine that the experiments in 

 question are something out of the ordinary. Possibly 

 they constitute the most remarkable of the various 

 types of life-juggling experiments with which this 

 chapter is concerned. 



The chief innovators in the art of growing living 

 tissues in an incubator are Drs. Alexis Carrel and 

 Montrose T. Burrows, of the Rockfeller Institute, 

 though Dr. Leo Loeb had earlier made tentative 

 experiments and Dr. R. S. Harrison was the first to 

 prove the feasibility of such investigations. Dr. 

 Harrison (1907) worked with embryological tissues. 

 Drs. Carrel and Burrows generalized the method in 

 1910. The tissues experimented with are fragments 

 of spleen or liver or skin of the chicken or of various 

 higher animals. Similar tests have also been made 

 with fragments cut from various abnormal growths 

 including malignant tumors. Indeed, tissues of al- 

 most every character may be utilized successfully. 



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