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absolutely in excess. It is generally feebly acid, often decidedly so 

 when first voided, the greater part of the phosphate of lime becoming 

 deposited while the urine still retains some degree of acidity ; it 

 however speedily becomes alkaline, owing probably to the excess of 

 mucus contained in it. Sometimes the crystals of phosphate of lime 

 are thrown down from the urine before its escape from the bladder ; 

 ordinarily, however, the urine is bright and clear when passed, and 

 the crystals are not formed until some time after it has been voided. 

 In collecting this phosphate for analysis, the object being to procure 

 it in as pure a state as possible and as free from phosphate of 

 ammonia and magnesia, oxalate and carbonate of lime, it should be 

 separated from the urine very soon after it has become deposited, 

 and before decomposition has had time to set in. 



On the Pathological Importance of Deposits of Phosphate of 

 Lime in Human Urine. 



Of the pathological importance of excess of phosphate of lime in 

 the urine not a doubt can be entertained, but certain reasons and 

 facts may be advanced to show that deposits of that phosphate have 

 a deeper pathological significance than those of the phosphate of 

 ammonia and magnesia. The proof of this is the more necessary, 

 since writers on the urine are in the habit of describing, as well as of 

 treating, deposits of the earthy phosphates collectively, and without 

 distinguishing between them : this course was natural enough so long 

 as they were unacquainted with the fact that deposits of phosphate of 

 lime in the state of crystals are of frequent occurrence, or so long as 

 they mistook them for a variety of the ammonio-magnesian phos- 

 phate. One reason why we should be disposed to attach greater 

 importance to the excess of the calcareous than the magnesian phos- 

 phate, is that most of the phosphoric acid of this last phosphate, 

 and all the magnesia, is derived from without, being contained in 

 the various articles consumed as food ; while for the phosphate of 

 lime, we have in the system in the teeth and bones, and also in the 

 nitrogenous tissues sources containing some pounds weight of this 

 phosphate. 



That the osseous system is subject to disintegration is certain, and 

 that the extent and rapidity of this differ remarkably in different 

 cases is equally so. This is shown by the simple fact alone of the 



