538 APPENDIX. 



has recently instituted experiments, under the direction of Julius 

 Vogel, on eight persons, for the purpose of ascertaining the 

 fluctuations in the amount of chlorine in the urine : the follow- 

 ing are the results of these investigations ; the mean amount of 

 chlorine in the urine is 10'46 grammes in the 24 hours, although 

 the quantity varies very considerably in different persons. In the 

 afternoon the secretion of chlorine is at the maximum (although 

 not immediately after dinner), in the night it sinks the lowest, 

 and again rises in the morning. Bodily exertion increases the 

 excretion of chlorine ; indisposition diminishes it somewhat rapidly. 

 The secretion is augmented by drinking water, but it is afterwards 

 proportionally diminished. When chlorine-compounds are taken 

 after fasting, the secretion remains for some time less than it 

 would otherwise have been. Even when no chlorine-compounds 

 are introduced into the system from without, a little alkaline 

 chloride is still separated with the urine. When more than 

 the usual amount of chlorine is taken up, the secretion is simply 

 augmented for a short time ; but, on the whole, less chlorine is 

 excreted by the urine than is taken up ; the excess of chlorine 

 must, therefore, be eliminated by some other channel. 



(44) Addition to p. 401, line 14. Redtenbacher* has, how- 

 ever, seen in 80 cases of pneumonia that the amount of the 

 chloride of sodium fell to a minimum ; at the crisis of the disease 

 nitrate of silver actually yields no precipitate in acidified urine ; 

 with the decrease of the inflammatory process the chlorides again 

 gradually increase. Even after the use of hydrochloric acid, 

 Redtenbacher was unable to detect any chlorine in the urine of 

 persons affected with pneumonia. According to the same observer, 

 the chlorine disappears for a short time from the urine during 

 relapses in pulmonary tuberculosis. In acute rheumatism, capillary 

 bronchitis, and typhus, the chlorine frequently, although not con- 

 stantly, disappears from the urine for a short time. 



We have already spoken in vol. i, p. 446, of the amount of 

 sulphates present in normal urine. Observations have been 

 instituted in reference to the fluctuations occurring in the amount 

 of sulphuric acid present in the urine ; among these analyses, 

 those of Bence Jonesf and of Gruner, J conducted under the direc- 



* Ber. d. kais. Ak. d. Wiss. zu Wien. 1850. 

 t Philosophical Transactions. 1849, pp. 252-260. 



J Die Ausschcidung der Schwefelsaurc (lurch den Ilarn. Inaug.-Abh. der 

 med. Fac. zu Giessen vorgcl. 1852. 



