4 
Journal of the 
to tinge the nuclei of the white corpuscles. This result may not 
he always readily brought about, perhaps requiring time and 
manipulation according as the blood itself may vary in quality. 
When it is apparent the nuclei have received colouration, every 
white corpuscle should be carefully examined with a view to the 
following results:—That one or more will be found to have, 
besides the colouration of the nucleus, a minute coloured spot, 
magenta stained, situate on the periphery of the white corpuscle 
wall. This fact, if once recognised, should be diligently sought 
for in any specimens of blood which havo been subjected to the 
prussic acid process. In addition to this change, another con¬ 
dition of the blood acted on by the acid can be noted—of course, 
without the magenta action—that, by carefully and gradually 
lessening the light under the object, the nuclei of the white 
corpuscles present a decided greenish blue or bluish tinge; and in 
addition to this, in some part of the specimen of blood, there will 
be found, in all probability, some solid iibrinous or other mass, 
with a decided deep blue tinge, a cyanide of iron, or Prussian blue 
re-action, due to the iron in the blood engaged by the prussic acid. 
Careful manipulation of the light in reducing it to a very low ebb 
is absolutely needful in order to display the blue tinge of the 
nuclei, and perhaps less care in finding the blue amorphous 
particles, as they exhibit a denser colour. Without a condenser 
to modify the light this experiment is not likely to succeed. 
(7.) We come now to the examination of the blood in another 
way, with a view to carry out the same inquiry. Mix magenta 
solution with prussic acid. The white corpuscles will be attacked 
as before, and the colouration of the nuclei, will be readily shown, 
as also the colouration of a macula on the periphery of the cell 
wall. The number of these white corpuscles will be found to be 
increased. In conducting the experiment in this way, we do not 
obtain the blue re-action of the prussic acid, as that is covered by 
the magenta staining. The above experiments, to my mind, servo 
to illustrate this point in the history of tl/e red corpuscle, that the 
action of the prussic acid has caused the newly formed red 
corpuscles to retrograde to the condition of the white by the 
dilatation of the cell covering, which, not having permanently 
adhered to the nucleus, sometimes carries away with it a small 
adhering portion of the nucleus, which takes colour, and is Been as 
