1889.] MICROSCOPICAL JOURNAL. 271 



it is better to drop a little staining fluid in the urine, as staining under 

 the cover-glass causes the sediment to fly across the field at an alarm- 

 ing rate of speed and settle on the outside of the glass. This may be 

 prevented by allowing the casts to dry on the slide and then staining ; 

 but this is apt to change their appearance and is not advisable. The 

 best way is to stain them before the cover-glass is put on. 



" Tube casts, or urinary cylinders, form by far the most important 

 pathological constituent of urinary sediment. They are so called be- 

 cause they are supposed to be moulds of the uriniferous tubules of the 

 kidney. After being thus moulded, they shrink and are carried out 

 with the urine. They are supposed to be formed by a coagulable sub- 

 stance in the blood, or by some morbid change of the renal epithelium. 

 According to their appearance and composition, casts have received 

 different names. If the mould of coagulated fibrin pass out with the 

 urine without blood or cell, it is called a hyaline or waxy cast. Ac- 

 cording as epithelium, blood, fat drops, or granular matter [the two 

 last from degenerated epithelium] are adherent to the moulds of fibrin, 

 the casts are called respectively epithelial, blood, fat, or granular casts. 

 These casts vary in diameter [from ^Vo to too" °f an bich] according 

 to the part of the tubule from which they come. Hyaline casts are 

 genei-ally smaller than those to which epithelium, blood, etc., are at- 

 tached. Mucous casts have also been described. Amorphous sedi- 

 ment and small crystals may adhere to casts, and they also sometimes 

 arrange themselves in a cylindrical form and deceive the inexperienced. 

 Casts of the urates and of bacteria may be mentioned. In cleaning 

 slides and cover-glasses, bits of linen threads are often left on the glass 

 and may be mistaken for hyaline casts." (Practical Notes on Urinary 

 Analysis.) Occasionally bladder or vaginal epithelium becomes rolled 

 up and looks very much like casts. It is almost superfluous to say 

 that, as the finding of casts is generally of grave significance, a deci- 

 sion should not be reached by one examination, but many slides should 

 be prepared. The laity soon knows the gravity of casts in the urine, 

 and let a man once be rejected by a life insurance company, it is a 

 serious shock to him. Therefore not without careful examination and 

 consideration should a decision be made in this most important subject. 



Cement for Glass. — A thin coat of " diamond cement" laid on 

 each surface of the glass, pressed together and left for two days, an- 

 swers admirably. Melt the cement by immersing bottle in hot water, 

 and put very little on — the less the better. — English Mechanic, Octo- 

 ber 2'j, i88q. o 



Close Shaving. — Through a microscope, a face which has been 

 treated to this process resembles a piece of raw beef. To make the 

 face perfectly smooth requires not only the removal of the hair, but 

 also a portion of the cuticle ; and a close shave means the removal of 

 a layer of skin all around. The blood-vessels thus exposed are not 

 visible to the unaided eye, but under the microscope each little quiver- 

 ing mouth holding a minute blood drop protests against such treat- 

 ment. The nerve tips are also uncovered and the pores are left 

 unprotected, which makes the skin tender and unhealthy. This sud- 

 den exposure of the inner layer of the skin renders a person liable to 

 have colds, hoarseness, and sore throat. — Medical Classics. 



