_ a 
On the Importance of introducing a New and Uniform Standard of Micro 
metric Measurement. By Professor Lyons. 
The author alluded to the great difficulties experienced by observers in enumerating, 
recording, and remembering the various kinds of measures now in use in these coun- 
tries and on the Continent, portions of the English and French inch and line, and 
decimal parts of the French millimetre. The high figure in the denominator and the 
number of decimal places are exceedingly cumbrous. He (Dr. Lyons) would pro- 
pose that some definite micrometric integer should be assumed, being a determinate 
part of unity. He proposed that this measure should be denominated a Microline. 
He did not mean definitely to bind himself to the adoption of any particular standard, 
but would propose provisionally that the one ten-thousandth part of the English inch 
should be assumed and denominated the standard Microline pro tem. The size of 
microscopic objects could thus be recorded simply, by saying they were one, two, 
three, or more Microlines in diameter. He would have his hearers bear in mind the 
present tendency of scientific men towards a decimal system. For his own part, he 
would prefer to assume as the standard Microline, some minute subdivision of the 
French decimal scale. 
TRANSACTIONS OF THE SECTIONS. 15 
_ Professor Lyons exhibited an instrument for the local application of chloroform, 
the invention of Dr. Hardy of Dublin, which for simplicity and effectiveness he 
thought contrasted very favourably with any similar instrument he had yet seen. 
On the Valvular Apparatus connected with the Vascular System of certain 
Abdominal Viscera. By Ropert M‘Donnett, M.D. 
A series of drawings were exhibited, showing the anatomical structure and arrange- 
ment of the valves situated at or near the point where the renal veins open into the 
vena cava ascendens in various animals as well as man. 
The author having spoken also of the beautiful valvular structures which in the 
lower animals are so constantly found guarding, more or less, completely the mouths 
of the hepatic veins, detailed some experiments performed by him, which seem to 
show not only an anatomical but physical grounds that these valves cannot act 
otherwise than in preventing, or at least checking any regurgitation of venous blood 
into the vessels thus guarded: on these grounds he was opposed to the so-called 
« Hepatico-renal”’ circulation. 
Dr. MILiincEN introduced to the Section a method he had adopted of preserving 
the vaccine virus in glycerine. 
On the Connexion between Atmospheric Vicissitudes and Epidemic Diseases. 
By Dr. PozNansk1. 
' The author exhibited an instrument for measuring the force and number of the 
pulsations of the arteries. 
Note on Electric Fishes. 
By Sir J. Ricuarpson, C.B., M.D., LL.D., P.RS. 
The author stated that there were not less than eleven genera of fishes known 
that had the power of giving electric shocks. There was one peculiarity in all these 
fishes, and that was the absence of scales. In every one of them an apparatus had 
been discovered which consisted of a series of galvanic cells put in action by a 
powerful system of nerves. He read extracts from a letter from Dr. Baikie, now 
engaged in exploring the Niger, in which that gentleman stated he had met with 
an electric fish in Fernando Po, and which he believed was identical with the 
_~Malapterurus, which had been described by Dr. Wilson, from the coast of Old Cala- 
bar. The natives called this fish the Tremble-fish. 
On the Employment of the Living Electric Fishes as Medical Shock- 
. Machines. By Professor G. WILson. 
The author stated, that in prosecuting researches into the early es of the 
