the heart's action, as we shall have hereafter more particularly to point out, and lastly and most importantly to waste the body by demanding an excess of vital transformation in order to maintain a supply of heat from within-a demand which cannot be supplied. Hence we have an explanation of the ill health and of the occurrence of phthisis in persons who exchange a hot for a much colder climate.

The amount of fluid which is thus lost by the skin may be approximatively ascertained by the series of experiments which we made upon fifteen phthisical patients in May and June (already referred to at page 65).

The table No. 4, page 78, contains a number of facts to which we may hereafter have occasion to refer to supply the information which we now seek.

The part of this table to which we wish now to refer has reference to the relation of the egesta to the ingesta.

In the various cases referred to the total fluid and solid egesta varied daily from 65'3 oz. to 143'1 oz., with an average extending over the whole month of 92.7 oz. The weight of the fæces, sputa, and urine varied in the different cases from 29.7 oz. to 67.7 oz. or a total average of 48'04 oz. The excess of the ingesta over the egesta varied from 326 oz. to 75.3 oz., with an average quantity of 44'66 oz., and if we deduct from that amount the carbon exhaled by the lungs, nearly the whole remainder will represent the fluid which passed off by the skin and lungs. The amount of carbon evolved was not ascertained, but

TABLE No. 4.

from our inquiries upon persons in health we find that 19 grs. of carbon are expired daily in quietude to each pound of body-weight, and as the average weight of these patients was 135 lb. the total daily elimination of carbon in health may be estimated at 6 oz. daily, and in a state of disease at fivesixths of that amount. Hence the amount of vapour eliminated by the skin and lungs was about 40 oz. per day, and this abstracted from the body nearly 40000 times as much heat as was held latent by that quantity of fluid when within the body.

Hence in the class of cases now under consideration we find the skin unusually active and abstracting heat rapidly from the body, when, at the same time, there is less transformation of nutriment than occurs in health, and consequently less heat produced within the body. As a necessary result the temperature of the body is reduced, the hands and feet become cold, and the depression and exhaustion of the nervous power ensues which is known to occur with excess of cold of the body. In an inquiry made upon 1000 phthisical patients, we found that 54 per cent. were constitutionally liable to coldness of the extremities. Of these 4.8 per cent. suffered from coldness of the hands, and 19.1 per cent. from coldness of the feet alone; whilst in 302 per cent. that condition affected both the extremities in the same person. This was observed in states of so-called health, but it must be much in excess of the frequency occurring in robust constitutions.

URINE.

The amount of urine evolved is perhaps equal to that in health, but varies with the activity of other outlets of the body.

We have shown in inquiries which were prosecuted upon ourself throughout the year, that there is very great variation in the amount of urine evolved in health at the different seasons of the year, and also that there is a relation between the amount of fluid evolved through this and other outlets. The experiments in phthisical cases just referred to, although extending over a long period, may not be taken to represent the quantity of urine which would be evolved at all seasons of the year, and must, therefore, be accepted with a certain amount of reservation. Moreover, we have shown that in these cases there was a very active state of the skin, and consequently a large amount of fluid passed away from the body by that outlet, and less would remain to be eliminated by the kidneys. The daily amount of urine varied from 21 oz. to 64 oz., and the average of all fourteen cases was 38.8 oz. during the whole summer month. The amount of urine in health varies greatly in different persons, and it is very difficult to obtain a standard with which it would be just to compare any individual case, or a few cases, but it is probable that the average now obtained is not less than occurs in health.

SPECIFIC GRAVITY.

We do not purpose to enter into a consideration of

the quality of the urine evolved in phthisis, but as an American observer* has made the unaccountable observation, that "in phthisis, as a general thing, its specific gravity does not exceed 1010," we think it right to cite the specific gravity in the cases of phthisis now referred to. The specific gravity was determined with great care, by means of an instrument with a large bulb, and graduated to a quarter of a degree, and at the same time the exact temperature of the urine was determined.

The inquiry was made in the day and night urine separately, and as the whole returns are too voluminous, we insert in the following table a copy of the record in the first eight cases.

It will be observed that there was much diversity in the returns of the specific gravity, so that on one occasion it was so low as 1007, and in several others as high as 1030. Usually that of the night urine (9 P.M. to 8 A.M.) was less than that of the day. We cannot determine the true average specific gravity in these cases without the laborious process of multiplying each return by the number of ounces of urine of the day and night separately, and adding the totals, but it will suffice if we represent the number of occasions on which certain specific gravities were found. Thus,

A specific gravity of 1030 and upwards was found in 4.3 per cent.

Extracted from the "Phil. Med. Reporter," Sept. 21, by "Dublin

Med. Press," Nov. 13, 1861.

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