94 
POPULAR SCIENCE REVIEW. 
complicated for explanation without drawings, hut the reader may find an 
account of the methods adopted, in a paper by Captain Noble, in the last 
volume of the Proceedings of the Institute of Mechanical Engineers. The 
pressure is measured by the indentation of a block of metal by a point 
attached to a plunger communicating with the bore of the gun. The results 
obtained by Captain Noble have a most important practical bearing, namely, 
the determination of the quality of powder which will generate the required 
velocity in the shot with the least injurious action on the gun. Comparing 
samples of fast-burning and slow-burning powder, it was found that the 
time taken by the latter to project a shot a certain space in the bore of the 
gun was five times that required by the former. The velocity at the muzzle 
was nearly the same in the two cases. The maximum pressure in the gun 
due to the fast-burning powder was double that of the slow-burning 
powder. 
Flow of Gases. — Professor Rankine has communicated to the Engineer a 
series of papers on the flow of gases through orifices, containing very impor- 
tant corrections of the formulae hitherto accepted. 
MEDICAL SCIENCES. 
Eccentricity and Insanity. — As a proof of the difficulty of drawing an exact 
line between these two morbid conditions of the mind, the American Quar- 
terly Journal of Psychological Medicine for October gives a curious case. A 
man made a will leaving all his money away from his relatives to found a sort 
of asylum for cats. The following is the last provision in the will : — “ I have 
all my life been taught to believe that everything in and about man was 
intended to be useful, and that it was man’s duty, as lord of animals, to 
protect all the lesser species, even as God protects and watches over him. 
For these two combined reasons — first, that my body, even after death, may 
continue to be made useful; and, secondly, that it maybe made instru- 
mental, as far as possible, in furnishing a substitute for the protection of the 
bodies of my dear friends, the cats — I do hereby devise and bequeath the 
intestines of my body to be made up into fiddlestrings, the proceeds to be 
devoted to the purchase of an accordion, which shall be played in the 
auditorium of the Cat Infirmary by one of the regular nurses, to be selected 
for that purpose exclusively — the playing to be kept up for ever and ever 
without cessation day or night, in order that the cats may have the privi- 
lege of always hearing and enjoying that instrument which is the nearest 
approach to their natural voice.” 
Cortis rods and their function. — Helmholtz has modified his opinion on 
this subject in physiology. Hitherto he regarded them as being connected 
with the perception of sound ; but now that it has been shown that they are 
absent from the cochlea of birds and as many birds have high perception of 
sounds, the aforesaid function cannot be attributed to them. 
The accessory Articular Condyles of the Skull . — At one of the meetings 
of the Vienna Academy during the past session, Herr A. Friedlowsky sent in 
a paper on the accessory articular condyles of the occipital bone, of man. 
