per

3. Make a further correction for middle and old age, by calculating according to columns 1 or 2, and then deducting 10 cent., if the person be between forty and fifty; 20 per cent., if between fifty and sixty; 30 per cent., if between sixty and seventy; and 50 per cent., above seventy.

These numbers are quite provisional, as the analyses are so few. Future observations will confirm or correct them.

4. Correct for diet.-If the persons have been starving for two or more days (as in some fevers), deduct one third from the calculation when made according to the table. If the diet be meagre, deduct one eighth or one sixth; if pretty plentiful, yet still below that of health, deduct one tenth.

5. Correct for movement. If there be total inactivity, deduct one tenth; if merely quietude, deduct one twentieth.

No one can be more aware than I am of the imperfections of the above plan. I merely offer it as provisional, and as affording us, as far as I can see, the only means of forming an approximative notion of the healthy excretion of a sick person.

Corrections ought also to be made for the amount of fluid drunk, the action of the external temperature, and the condition of the other eliminating organs, &c., but I am at a loss how to determine the proper figures for these agencies. Their amount, however, should never be disregarded.

I have only given the chief urinary ingredients, as the amounts of the rest are so uncertain. The uric acid, being so little influenced by weight, cannot be calculated.

I subjoin a case of mine, to show the working of the plan. A healthy man, aged thirty, on moderate hospital diet, weighed 114 lbs. Required the physiological amount of urea in twentyfour hours.

=

3.53 × 114 402.42 grains. Correct for moderate diet; deduct one eighth :

505-4250-3 3521 grains.

=

Column 5, by assuming that the excretion is more than that of column 1, by one quarter of the difference between column 1 (excretion in men) and column 3 (excretion in children from three to eight).

Columns 4 and 5 are merely provisional statements.

Correct for bodily inactivity; deduct one twentieth :

352.1 17.65 = 334-45 grains.

The physiological amount determined by actual experiment (mean of six days) in this man was 346-7 grains, being only 12 grains above the calculated amount.

If a patient's weight cannot be determined, then no correct calculation can be made; but even here it will be found useful to learn what is supposed to be the weight, and to form a rough estimate of the physiological excretion.

In some cases of disease, the urinary excretion can at once be told to be abnormal-to be either too great or too small, when, on a mean of several days, we find it much below or above any of the physiological means. Thus if we find a man aged twenty passing, on an average of six days, 850 grains of urea daily, we are quite sure this is abnormal, for the highest normal mean amount is 688 grains.1 But we could not tell how much this exceeded the man's natural amount, without reference to his weight. Supposing his weight was 120 pounds, each pound weight would excrete 7·08 grains, which would represent an increase of 3 grains to each pound, or nearly double the healthy amount; if he weighed 180 pounds, instead of 120, the extra amount would be only a little more than one grain to each pound, or about one fourth more than normal.

Before commencing the subject of this chapter, a preliminary objection must be examined.

Considering the occasional difficulty of diagnosis, the frequent complications of diseases, the variations in the symptoms produced by individual peculiarity, or by alterations in the force of a morbific cause, it may be argued that, instead of describing the alterations in the excretions as associated with a definite disease, it may be better to refer them to a special definite state of the system, such as heightened temperature, quickened pulse, &c.; to connect them, in fact, with a well-defined single condition, and not with a complex assemblage of symptoms.

Undoubtedly the varieties in disease are very numerous, and, in the same nosological affection, the predominance of certain symptoms may give to one case a peculiar character which may greatly influence the excretions. For example, acute rheumatism is a very definite disease; but in one person it may be attended with profuse sweating; in another, with a dry skin. Now, the

1 In this application consists the great use of the tables in the Introduction; and it is hoped that tables for women and children, with the body-weight added, will soon be formed.

urine in the two may possibly be affected by this difference in symptoms, though the disease is identical. So also in typhoid fever, in one case diarrhoea may be profuse, in another absent; the urine will be very different in the two persons.

But, on further examination, the force of the objection disappears. The whole art of medicine is based on the postulate, that diseases can, as a rule, be diagnosed; that they form a series of natural groups; can be recognised when they again appear; and are known, from experience, to have a certain course and tendency, and to require certain treatment. If this were not possible, the art of medicine would become a mere symptomatology, without coherence, utility, or scientific character. As, therefore, we can undoubtedly distinguish different diseases, we must necessarily arrange the phenomena of the urine under the same headings; and we have simply to do for disease what we must do for health, viz., to determine, first, what is the typical constitution of the urine proper to any particular disease, and secondly, the alterations in such constitution produced by incidental circumstances, proceeding from the physiological character of the patient, or from peculiarities or variations in the course of the disease, or from treatment.

In the following pages I have not attempted to enumerate all the diseases which can be diagnosed, as the condition of the urine is not accurately known in some of them. I have selected merely well-marked types of disease, in which the analyses of the urine are sufficiently numerous and complete.

The arrangement of the different diseases is a matter of some difficulty; but the method which appears most adapted for the purpose in hand is to adopt the grand division into acute and chronic diseases, and to consider first the non-renal, and then the renal, diseases, under these headings. I have left out many analyses recorded in works, as strong medicines were given at the time, and it is impossible to know what were the effects, respectively, of the disease and the medicine. I have also seldom alluded to any analysis of the urine of a single day, unless the result was manifestly beyond the range of possible

error.

1 We have, of course, to judge of the urine in diseases uncomplicated by treatment, and then we must learn what charges in this composition are produced by remedies. It is with great reluctance that I have omitted any reference to several analyses which have given their authors no little trouble. But it seemed to me better to do this than to record observations which can only confuse the subject and increase its difficulty. I have judged myself with as much rigour as other people, and have thrown aside an immense number of analyses, as too imperfect to be used.

ACUTE DISEASES.-NON-RENAL.

ACUTE discases are broadly distinguished into two classes; in one of which the disease must terminate in a certain time, and cannot become chronic; while in the other, the acute may pass into the chronic stage, and the disease may continue with migitated symptoms for some time.

Most of the diseases of the first class are specific, i. e., are attributable to some special cause, or morbid entity, which is also, in many cases, capable of increase in the body on which it acts.. With one exception (cholera), the specific diseases have a constant character; they are all febrile, and many of the conditions present in the urine result, not from the specific nature of the diseases, but from the febrile action which is common to so many affections.

SECTION I.

INTERMITTENT FEVER.

The observations hitherto made are divisible into two series1. The consideration of the urine during the fit, as compared with the urine of a non-febrile period.

2. The condition of the urine of twenty-four hours during a fever day, as compared with the twenty-four hours' urine of a non-fever day.

I. The Urine during the fit and the apyrectic period.

Normal Constituents.

1. The water is increased in amount (Becquerel,1 Traube,2 Redenbacher,3 and Ringer4) during the cold and hot stages; it is most abundant at the termination of the cold, or the commencement of the hot stage; it decreases during the

1 Becquerel, Traité de Chimie path., Paris, 1854, p. 345; and Semiotique des Urines, Paris, 1841.

2 Traube and Jochmann, Deutsche Klinik, No. 46, Nov., 1855.

3 Redenbacher, Henle's Zeitschrift, (N.F.) Band ii, p. 384.

4 Ringer, Med.-Chir. Trans., 1859.

Jones, Trans. of Amer. Med. Ass., 1859.

latter part of the hot stage slowly, and rapidly during the sweating state (Ringer).

The amount of increase is various, but it is sometimes quadrupled. It is in no relation to the quantity of fluid drunk, and may be great when this is small (Ringer). The amount of water passing off by the skin and lungs in various stages of ague is unknown. The cause of this increase in the quantity of urinary water is not clear. It may be that the cutaneous excretion is lessened, and that the urinary flow is compensatory; or there may be some peculiar nervous state, which alters the pressure in the vessels of the kidney. During the intermission, it is lessened (Redenbacher).

2. The urea. The amount of urea excreted daily by a person with ague, but who is not actually suffering from a fit, is less than in health. This may be owing simply to loss of appetite, or to the imperfect nutrition or metamorphosis, or to retention. Exact experiments are yet wanting on this point.

Directly the fit commences, i. e., at the very first moment of elevation of temperature, or even for some time before this, the urea, according to the latest observers, suddenly increases,2 although every known cause of increase, as food, exercise, &c., be avoided. The increase lasts during the cold and hot stages, and then sinks, sometimes gradually, sometimes suddenly, through the sweating stage, or into the commencement of the intermittance. The amount then falls below the healthy

average (Moos).

The amount of ureal increase appears to be variable. Sometimes it is very considerable; in Traube's and Redenbacher's cases the amount was as much as three times the quantity that would have been excreted during an equal period of time on a fever-free day. In Mr. Ringer's case, it was even a little more than this. Moos found much less-indeed, comparatively little in neglected intermittents of old date; but, Redenbacher found the increase as great in an old neglected case as in other instances. The type of the disease (quotidian, tertian, &c.) has no influence.

1 Zimmermann, Hæser's Report on General Pathology, in Canstatt's Jahresb. for 1854, p. 108. Schneller, Valentin's Report on Physiology, in Canstatt for 1855, p. 108. Golding Bird, Urinary Deposits, 4th edition. Jones, Trans. of the Amer. Med. Assoc., 1859, vol. xii, p. 507; and several later observers.

2 Traube, op. cit. Redenbacher, op. cit. Moos, Henle's Zeitschrift, Band vii, p. 291. Ringer, Med.-Chir. Trans., 1859.

3 The excretion per hour, in one of Redenbacher's cases, rose relatively from 1 to 3 during the hot and cold stages, and fell to 14 during the sweating stage. The exact amount during the cold and hot stages was no less than 4:144 grammes per hour. Had this continued for 24 hours, it would have furnished the enormous amount of 99 grammes of urea (1536 grains).