PART II. 



STATISTICS OF OBSERVATIONS. 

 SELECTION OF SUBJECTS. 



The infants studied were all kept in the children's ward of the Massa- 

 chusetts General Hospital and were selected for the most part from 

 those coming to the Out-Patient Department; a few came directly 

 from the Boston Lying-in Hospital. In many instances they were 

 placed in the wards for the purpose of having their digestion studied; 

 in a few cases they came because of some slight indigestion or because 

 they were not gaining weight satisfactorily. 



Each infant that enters the children's ward of the Massachusetts 

 General Hospital has a complete physical examination, including an 

 examination of the ear drums; careful notes are also made as to the 

 general appearance, actions, and digestion. When the physical exami- 

 nation of the infants selected for observation was normal — in most 

 instances the records were naturally of a negative nature, as for example 

 "no enlargement of the peripheral lymph nodes" — and the infant led 

 a regular and uneventful life, it was considered a normal infant. In 

 some instances the subjects were below weight but appeared normal in 

 other ways. In such cases, the fact is recorded in the statistics. 



The infants were under the general care of one of us who saw them 

 each day, but the immediate care was detailed to the house physician 

 and excellent trained nurses. The routine throughout the day was 

 regular. They were weighed naked at the same hour each day by 

 the same nurse. The nurses also recorded carefully how much food 

 was eaten; the percentages of the food components given and the 

 number of calories in the food taken were roughly calculated for each 

 day. Notes were kept as to the character of the dejections, and the 

 pulse-rate and body-temperature were recorded twice a day. The 

 clothing was the ordinary clothing used in hospitals for infants of their 

 age; the beds were the usual hospital cribs. The house officer took 

 careful histories of all the infants, his physical examination and bed- 

 side notes being verified by one of us. These records were made 

 and the infant studied before any observations were made of the metab- 

 olism in order to control all factors so far as possible. 



Infants who were quiet and comfortable were considered to be the 

 most favorable subjects for observation, but we were frequently dis- 

 appointed in the results, as many infants who were supposed to be 

 absolutely quiet during the 24 hours did not prove to be so. This 



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