BAIR.D &TATLOCK (LONDON) LTD. 



the capillary blood tubes ; these arc placed in the haomatocrite frame, and the handle attached to the high-speed 

 spindle when the tubes can be rotated at a speed of 5,000 revolutions per minute. 



This process is simple and rapid the blood does not have time to coagulate, and by centrifugal force the 

 red corpuscles are thrown to the end of the tube, and will occupy about half the tube, or to the mark 50. The 

 white corpuscles being next in specific gravity, will occupy a position between the red corpuscles and liquor 

 sanguinis, which is found in the proximal end of the tube, quite clean and free from corpuscles. 



URINE EXAMINATION. Specially graduated percentage tubes are supplied tapering to one end, and these 

 are revolved about 2,500 times per minute. This speed is quite enough to precipitate even the hyaline casts 

 without breaking them or altering their form. 



SPUTVM EXAMINATION. A small quantity of sputum is stirred in a porcelain dish until it is apparently 

 homogeneous ; two small tubes are then filled, placed in h;ematocrite frame, and revolved for three minutes 

 at a speed of 5,000 revolutions per minute. The solid portion can then be transferred to slides for microscopical 

 examination. 



IN WORKING WITH SMALL QUANTITIES, where the micro-organisms are few, two large sediment tubes are 

 used, and after the sediment has been precipitated, the greater part of the liquid is decanted, and the remainder 

 transferred to small tubes for final examination at high speed in the haematocrite frame. 



MILK EXAMINATION. 5 c.c. of milk are placed in each bottle by a pipette, i c.c. of Solution A added, and 

 well shaken. Then by another pipette Solution B is added by drops until the bottles are filled to the zero mark 

 on neck, the bottles being well shaken in the meantime. They are now placed in the buckets and whirled for 

 about one or two minutes, after which the fat rises to the top of the graduation, and can be read off in direct 

 percentages. If the milk is richer than 5 per cent., add an equal quantity of water, mix thoroughly, and 

 multiply the result by two. 



SOLUTION A. SOLUTION B. 



Fusel Oil ... . . . . 37 parts by volume. Sulphuric Acid 



Wood Alcohol . . . . i 3 Distilled Water 



Hydrochloric Acid . . 50 ,, 



50 parts by volume. 

 5 



Haematocrite. 

 878 



878 



879 



878 s Centrifugal Machine, witli two buckets and haematocrite, for separation of blood, urine, etc. 

 with clamp for fixing to table, with two graduated tubes for urine, and two capillary 

 blood tubes . . . . . . . . . . . . . . . . ..250 



879 s Centrifugal Machine, with two buckets, arranged to be driven by high water pressure, for the 



separation of urine, milk, etc., with four plain tapered tubes .. .. .. .. 2 10 



CROSS STREET HATTON GARDE1ST, E-C 



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