THE URINE. 293 



ingesta, &c. The urine of a healthy adult, recently made after a 

 tranquil repose, is generally a" clear " watery fluid of a nidorous 

 smell" while warm, " and of a lemon " or amber " colour," saline, 

 bitter, and disagreeable to the taste, " and contains a variety of 

 matters? held by a large quantity of water in solution, and 

 differing " in their absolute quantity in different persons, and in 

 the same person at different times. 



The more aqueous fluid is taken, and the less the skin and 

 lungs secrete, as in cold weather, the larger the amount of water 

 in the urine, which is then paler, more copious, and lighter. The 

 opposite circumstances, as well as exercise or feverishness, render 

 it high coloured, scanty, and heavy. Its usual specific gravity 

 is from 1015 to 1025. Much of the matters dissolved subside 

 in the form of a pale brown or reddish sediment after it has 

 stood, if the individual is feverish or dyspeptic, and the tem- 

 perature to which it is exposed is low ; and they dissolve again 

 if it is warmed. The quantity made daily by adults in health, 

 though much influenced by the quantity of liquids drunk, is, 

 perhaps, on the average, about three pints in the twenty-four 

 hours. After standing some time, the urine, which, when first 

 made in health, is acid, becomes alkaline, emits a strong ammo- 

 niacal smell, and is covered with a white mucous pellicle, in which, 

 as well as on the sides of the vessel, crystalline phosphate of mag- 

 nesia and ammonia is seen : yellow cubic crystals of chloride 

 of ammonia are then deposited, next yellow octohedrons of 

 chloride of ammonia, and lastly microcosmic salt or the fusible salt 

 of the urine, phosphate of magnesia and ammonia. The fluid in 

 the mean time becomes a brown and foetid syrup. 



The following is Berzelius's analysis of urine, in 1809^ : 

 Water ; ,,- : 933-00 



Uric acid - - a ' - 1-00 



hausen's Dissertation (which gained the second prize) de viis clandestinis urinee* 

 Berol. 1820. 8vo." 



Sir Everard Home observed, in his experiments on the spleen, that colouring 

 matters began to manifest themselves in the urine about seventeen minutes after 

 they were swallowed, became gradually more evident, then gradually disappeared, 

 and after some hours, when the mass had unquestionably passed into the intes- 

 tines, again tinged it as strongly as ever. 



P See Fr. Stromeyer, Theoret. chimie, t. ii. p. 609. 

 : Med. Chir. Trans, vol. iii. 



