8- 9 ... First Set. Mean of 4 Days. Breakfast at 8. Dinner at 4. Free Acid or. Alkali dis- charged per hour. Remarks. + 0-83. + 0-66. 0-60 ? 0-36. + 0-11. + 0-35.
906
DR ROBERTS ON SOME OF THE
Article II-
Observations on some of the Daily Changes of the By Wm. Koberts, M.D., Physician to the Manchester Royal Infirmary. (Continued from p. 825.)
Urine.
4. The Reaction of the Urine.?The well-known researches of Dr on the acidity of the urine have in this country, since 1849, greatly modified the old opinion, that the reaction of healthy urine was necessarily acid. He propounded the hypothesis that the stomach and kidneys were, as to their reaction, in a state of antagonistic correspondence. When the former was empty, its lining membrane was neutral, or sometimes even faintly alkaline; and at this time the urine was strongly acid. On the other hand, when the stomach became charged with the sour gastric juice for the digestion of the food, the urine then became less acid, or changed to alkaline ; when digestion was completed, the gastric acid re-passed into the blood with the chyle, and restored Lhe acidity of the urine. The multiplied facts on which the conclusions of fact rested, and the admirable theory by which they were harmonized, procured for both a ready acceptance among Dr Jones' countrymen ; and his teaching came to be regarded as an established physiological doctrine. Time, however, did not improve the position of the new doctrine. On the contrary, the experience of observers in this country and in Germany tended to re-establish the old opinion, that the healthy urine was invariably acid, except from the effect of caustic or carbonated alkalies, or the salts of the vegetable acids, which were broken up in the blood and appeared in the urine as carbonates. Dr Beneke2 found in his own case, that although the urine was examined on twenty-three days, he could not discover any depression of the acidity as caused by food. He records, in addition, not less than a hundred day-observations on different sick and healthy persons with this result, that although the urine did occasionally show a depressed acidity, and even an alkaline state, after a meal, and especially after breakfast, yet this was very far from being constantly the case. Dr Julius Yogel also found that observations made partly by himself, and partly by pupils under his direction, did not yield support These results, he states, " showed to the views of Dr Jones. uniformly that the greatest quantity of acid secreted per hour by the kidneys occurred during the night, the least in the forenoon, while a medium quantity was discharged in the afternoon after the principal meal. These results are therefore unfavourable to the conclusions of Dr Bence Jones, but do not tell conclusively against
Bence Jones1
1
Philosophical
Transactions for 1845 and 1849. Archiv. des Vereins fur Wissensch. Heilk., vol. i., p. 438.
907
DAILY CHANGES OF THE URINE.
inasmuch as other circumstances may have had an influence the amount of acidity."1 Dr Seller states, that in a good many trials he has not been'able to satisfy himself " that the rule, as laid down by Dr B. Jones, is generally applicable in Edinburgh ; certainly not to the extent that the urine loses entirely its acid character, or that it becomes alkaline." Nevertheless, it has seemed to him " that the variations in the degree of its acidity are in some measure governed by the existing state of the stomach."2 It seemed, therefore, not undesirable, in the face of this contradictory testimony, to submit the question to a new investigation, and to inquire if means could not be found to reconcile the conflicting facts, and ascertain with some precision what effect food had on the reaction of the urine. To this end the urine was examined at short intervals,?after a meal, usually every hour; and at periods more remote, every two hours. The hourly flow being thus ascertained, the absolute quantity of free acid discharged per hour was estimated by a test solution. Dr B. Jones, in his experiments, was content to gauge the amount of acid in 1000 grains of the urine, without reference to quantity per hour; and it was therefore objected to them, that the varying concentration of the secretion, especially the great dilution which follows free potations, vitiated the conclusions deduced. The objection, however specious, lies with very little justice against these researches; for Dr Jones was always careful to specify the density of every urine which he examined, and in this way to guard against any very great fallacy from unequal concentration. The method of hourly estimates has, however, unquestionably the merit of superior exactness ; hence it was adopted in the following observations. The mode of proceeding was to heat five hundred grains of the urine, and to add gradually a dilute solution of caustic soda to saturation. If the urine became alkaline, dilute sulphuric acid was used in the same way to ascertain the degree of alkalescence. Both test solutions were made of equal saturating powers, each 100 grainmeasures being equivalent to one grain of dried carbonate of soda. In this way the acidity or alkalinity per 1000 grains was ascertained ; and from this, and the quantity of urine secreted during the hour, the hourly amount of free acid or free alkali discharged was com-
them, on
puted.
confirmed in the fullest manner a meal, be it of animal, or mixed food, has a powerful and constant effect in lowervegetable, ing the acidity of the urine, frequently even rendering it alkaline. The following table exhibits the results obtained with a mixed diet. The numbers indicate grains of dried carbonate of soda. The results of these
experiments
the conclusions of Dr Bence Jones, that
1 2
Vogel, Anleitung zur Analyse Edinburgh Monthly Journal, Jan. 1859.
Neubauer und
des
Hams,
2d
Ed.,
p. 175.
908
DR ROBERTS ON SOME OF THE
but two meals taken each day; so that after dinner a of fasting ensued, until breakfast next morning. No alcoholic liquors were taken during the progress of these experiments. The days of the first set were not consecutive ; whereas those of the second set (with one exception) were successive days. The plus sign is prefixed when the urine was acid, and the minus sign when it was alkaline:? There
were
long period
ORDINARY MIXED FOOD.
Second Set.
First Set.
Mean of 7 at 8.
Mean of 4 Days. Breakfast at 8. Dinner at 4. Time of
Day. Free Acid or Alkali discharged per hour.
7- 8
Breakfast Dinner at 2.
Days.
A.M.
+
Free Acid or Alkali dis charged per hour.
Remarks.
-1-0-52
0-83
Breakfast at 8.
Breakfast at 8. 8- 9
...
9-10
...
10-11
...
11-12
...
12- 1 P.M. 1- 2 ...
+
0-66
?
-f
( Three times alka0-60
0-36
+ 0-11
Eemarks.
j (
line,
C
once
?
