basic salt. The monobasic phosphate, which 

 is seen in neutral or only slightly alkaline 

 urine, presents the microscopic appearances 

 as under (Jig. 793). 



Fig. 793. 



The bibasic salt, which is observed in highly 

 ammoniacal urine, gives the following figures 

 (fig. 794). 



Fig. 794. 



URINE. 1283 



DEPOSIT OF EARTHY PHOSPHATES. casionally has a light greenish hue. The de- 



The earthy phosphates, consisting of mag- P osit W , hen allowe , d to . colle u ct in a S lass vessel 

 nesia in combination with ammonia and phol- 1S , ra [ elv feen otherwise than as a floating 

 phoric acid, are seen as deposits in the urine d l !| collectin S at bottom and closely re- 

 in two forms, viz. as a monobasic and a hi- seil j bhn g the appearance which would be put 



on by the presence of an excess of the mucus 

 of the bladder natural to the urine. 



It has recently been stated, by Dr. Frick, of 

 Baltimore, that the crystalline masses, in the 

 form of dumb-bells, described by Dr. Bird as 

 consisting of oxalate of lime, are really com- 

 posed of lithic acid. It is true that lithic acid 

 occasionally assumes a form more or less re- 

 sembling the dumb-bells figured by Dr. Bird, 

 but scarcely so nearly as to be easily mis- 

 taken for them. Dr. Harris Wilson has also 

 recently shown that lithic acid may be made 

 to assume a form nearly approaching in 

 character to the dumb-bells. I have ex- 

 amined, with Dr. Bird, some specimens of the 

 dumb-bells, and am satisfied that those we 

 operated upon were composed of lime in com- 

 bination with an organic acid. In a paper 

 recently published by Dr. Bird in the Medical 

 Gazette, some reasons are given by him for 

 believing that acid to be the oxaluric, and not 

 the oxalic, and there would appear good 

 grounds for the adoption of that opinion. 



DEPOSIT OF CYSTINE. 



This substance, which is not one of the 

 ingredients of normal urine, is an organic 

 body, occasionally existing as a deposit in the 

 form of flattened hexagonal plates. Under 

 Urine depositing the first of these two th e microscope it presents the following ap- 

 varieties of sediment is generally of lighter pearances (fig. 796). 

 colour than natural, and of moderately high 

 specific gravity. 



The second variety, if not occasioned by 

 the use of alkaline remedies, generally indi- 

 cates important mischief in some part of the 

 urinary apparatus, and is often combined with 

 large quantities of epithelium, mucus, pus, and 

 blood corpuscles. 



DEPOSIT OF OXALATE OF LIME. 



This deposit, which is composed of lime in 

 combination with an acid foreign to the con- 

 stitution of healthy urine, presents itself under 

 the microscope in the following forms, first 

 described by Dr. Golding Bird (fig. 795). 



Fig. 795. 



O 



CARBONATE OF LIME DEPOSIT. 



This rare deposit exists in the form of 

 spherical masses, more or less crystalline, and 

 apparently made up of slender rhomboidal 

 prisms, diverging from a centre. It presents 

 the following appearance under the micro- 

 scope (fig. 797). 



Fig. 797. 



The appearance of dark crystals, looking 

 like cubes, is observed when this deposit is 

 allowed to dry. The transparent spot in the 

 centre is caused by reflection from the sides 

 of the octohedron. 



Urine depositing oxalate of lime is generally 

 of about the normal specific gravity. It oc- 



HIPPURIC ACID. 



This exists occasionally in excessive quantity 

 in human urine in disease. Under the micro- 

 scope it shows the following appearance (fig. 

 798). 



4 N 2 



