NOTES AND MEMORANDA. 
223 
mitted directly to the surface of the injecting jSuid, and the pressure 
is registered by a manometer. The nozzles used vary in diameter 
from 1 to 4 millims. The fluid used is a 10 per cent, mixture of 
Seitels's Berlin blue suspended in firm size. This does not stain the 
tissue, because it is not in solution, yet its granules are too small to 
be seen by any power of lens in my possession. That it is not in 
solution is certain from the fact that it is completely removed from 
the fluid by adding some albumen and boiling. Similar but not so 
satisfactory results may be obtained by Davies's granular carmine ; 
but here the granules are too large to enter the canals, save under 
such pressure as produces frequent extravasation. 
One disadvantage of the Berlin blue is that it contains a little free 
acid, and must do so to remain visible. After a short time this acid 
destroys the colouring of the stained nuclei ; so that, save in an 
almost perfectly fresh specimen, it is impossible to demonstrate the 
relations of the nuclei to the canals when distended by the injection. 
The method of injection of these canals is apparently very rough. 
It consists simply in inserting a small nozzle superficially into the 
substance of the cord over and parallel with the course of a vessel, 
tying it in, and injecting under a low pressure of 50 or 60 millims. 
of mercury. 
Schweiger-Seidel made the very obvious objection to this (Eeck- 
linghausen's) method that any appearances presented by it would be 
simply those of extravasation. Such was my own belief when I first 
tried it on the cord ; but very short experience showed me that the 
result was a regular and uniform injection of a system of canals, and 
that extravasation was very rare and always limited to the immediate 
neighbourhood of the wound in the cord. With the whole apparatus 
at a temperature of 47° and a pressure of 60 millims., I have injected 
a column of the cord for a distance of 9 inches in about half an hour. 
The injection travels rather more rapidly in the direction from the 
child to the placenta than in tlie opposite direction. 
I have repeatedly seen minute streams of the blue injecting fluid 
flowing from the surface of the cord into the water surrounding it, 
even at as low a pressure as 65 millims., with a nozzle only 1 millim. 
in diameter ; yet at a pressure of 350 millims. I have not produced a 
rent in the surface of the cord, though I have produced numerous 
extravasations into the alveoli and into the neighbouring columns. 
American Observations on Cellulose in Blood. — We desire to 
call attention to tlie published results of Mr. T. Taylor's (Government 
Microscopist, U.S.A.) investigations, which we think are likely to 
bring American science into contempt. He has lately been publishing 
a series of papers, which are the veriest nonsense in reality, so much 
so that we are surprised at their appearing as they do in a Govern- 
ment report. In the first place, the author never takes the trouble to 
inquire what has been done in European countries on the subject, 
and he plunges into a complex question entirely foreign to his 
pursuits, and the highest power he has employed is 150 diameters. 
Why, he could barely see the blood-globules of man with such a 
power. Will anyone who has ever examined the blood under a high 
