From this tabular statement of the results in five cases it will b seen that, as stated above, the results of the operation are trifling when we consider its severity. In one case, No. 16, the output of urea was increased from 7 to 10 grams per diem. In this case the ingesta were not determined, and the apparent increase may have been due to an increased diet. In No. 22 the diet was the same before and after the operation, but there is an increase in the urine and urea after the operation. This case is quoted because it illustrates the maximum effect produced; in no other case was so great an effect observed. In the other cases the effects on the urine, &c., are so slight as to be well within the limits of experimental errors. The loss in body weight is trifling when compared with that described below as resulting from the second operation. The greatest loss observed was in Dog 22, where the body weight fell from 14 lbs. to 12 lbs. The specific gravity of the urine is not permanently affected by the operation. In the first few days after the operation, whilst there is hæmaturia, the urine is frequently more abundant in quantity and the specific gravity then is temporarily lowered, but this soon passes off, and the urine returns to its normal quantity and density.

The Results following the Second Operation.

The results following the removal of the second kidney differ widely from those described above as following the first operation, in that there are frequently no immediate ill effects, the animal running about, &c., within a few hours of the nephrectomy, and there is but little shock, hæmorrhage, &c., when compared with the first operation. The remote effects, however, are very marked: a widespread disturbance of nutrition ensues, accompanied by extreme wasting, hydruria, and polyuria, and with these a fall in the body temperature and a great increase in the nitrogenous extractions of the tissues, provided a sufficiently large amount of kidney has been removed at the first operation.

In all cases the wound has healed up rapidly and soundly, and in no case has death resulted directly from the operation. Out of the fifteen experiments, the first was killed five days after the second operation, and at that time the animal was in sound health. In four cases, No. 2, No. 11, No. 19, and No. 21, the animals were killed 47 days, 60 days, 14 days, and 30 days respectively after the second operation, and the results observed in them will be described below (vide Table IV). In the remaining ten cases the dogs either died of a rapidly progressive asthenia, or else they were killed at a time when they were practically moribund.

The results in four cases out of the ten are given in the following table:

From this table it will be seen that the second operation is followed by a great increase in the amount of urine excreted, and also by a large increase in the output of urea. The increase in the urinary water, however, is greater than the increase in the urea, although the latter, as seen above, is greatly augmented.

This condition of polyuria is accompanied by great wasting.

Thus the weight of Dog No. 6 fell from 11 lbs. to 8 lbs. in 50 days.

This wasting is rapid in its course, and is not materially checked by a liberal diet, when the animal's appetite will admit of it. The appetite frequently fails somewhat, but the animals will eat meat in large quantities to within a short time of their death, although they refuse dog biscuit. There is also great thirst, and this, no doubt, is in close relation with the hydruria. When the polyuria is fully established, the rectal temperature falls, so that ultimately it may be as low as 97° F., or even 95° F., the normal temperature varying between 101° F. and 102° F. This condition of polyuria leads to a more or less rapid death; all the animals in Table II either died, or were killed because moribund, in from two to six weeks after the second operation.

The following table gives the results in the remaining six cases out of the ten rapidly fatal cases :—