12 



METABOLISM IN SEVERE DIABETES. 



thus obtained are a standard of comparison to determine whether in a given 

 case the conditions have been correctly adjusted for the use of the values for 

 dextrose which are recorded in table 1. From these controls the values for 50 

 and 100 mg. obtained from a 0.5 per cent or 1 per cent standard solution of 



pure dextrose were usually selected for the first tests. The quantities to be 



Dextrose 

 compared should be the q q ratios, as the limits of error of these are evi- 

 dent from the table. 



er 



Table 1. Reduction values for dextrose. 



'Average factor between 4S and 192 mg. copper, 0.522. 



This abbreviated table is to be used by means of its ^ " ratios, which 



are factors for converting the reduced copper to its corresponding amount 

 of dextrose. The most important property of these ratios from a practical 

 standpoint is that they change their value slowly in comparison with the 

 amounts of reduced copper to which they pertain. For amounts of reduced 

 copper between 48 and 192 mg. no table is necessary, as the ratios fluctuate 

 about a mean common factor of 0.522. In all other regions of the table it 

 should be observed that the slow change of the ratios will enable the operator 

 to interpolate mentally the required ratio for any amount of reduced copper 

 lying between two adjacent values of column n. For the very small amounts 

 of dextrose the third decimal place has no practical significance. 



CALORIMETRIC MEASUREMENTS. 



It is a matter of much regret and no little chagrin that during the greater 

 part of the time the new experiments on diabetics were being carried out the 

 results obtained with the bed calorimeter were vitiated by some then unknown 

 factor, so that the accuracy of the heat measurement in about two-thirds of the 

 experiments is seriously questioned. In about one-third of the experiments 

 we know the results to be satisfactory and accurate, but we have discarded all 

 of the data rather than select arbitrarily one-third of the material for presen- 

 tation. 



The index of this inaccuracy is to be found in abnormal relations between 

 the carbon-dioxide production, the oxygen consumption, and the heat produc- 



