SCIENTIFIC SUMMARY. 
331 
those which excite^the idea of yellow or blue, and so for other senses. I 
advocate this undulatory theory of sensation in preference to the theory 
of distinct conductors — 1st, because it is simple. 2ndly, because it is 
strongly supported by analogy, when compared with wave propagations in 
other departments of science. 3rdly. Because it appears to be in harmony 
with a large number of recognised physiological facts, which seem inex- 
plicable upon the theory of distinct conductors.” 
A New Opthalmoscope has been devised by M. le Dr. E. Javal. The 
mirror is a plate of glass covered by a thin layer of platinum, and the lenses 
which serve to' correct the refraction of the patient or the observer are re- 
placed by a small Galilean telescope. This, by a simple mechanism, is 
made to act as an optometer, and is exact as well as convenient. A greater 
magnifying power is obtained by this contrivance than by ordinary instru- 
ments, while the remark is made that the instrument is capable of improve- 
ment in some details. It is a great desideratum to be able to correct hyper- 
metropia and myopia, in all degrees, without the trouble of changing the 
glasses, and to gain a greater amplification of the fundu3, and we hope 
this new opthalmoscope may be perfected. 
A National Collection of Surgical Instruments. — Sir William Fergusson 
has proposed to form a national collection of surgical instruments, to be 
placed in the Museum of the College of Surgeons, London, to illustrate as 
far as possible the progress of surgical art in Great Britain, and the improve- 
ments made from time to time in surgical appliances and instruments. 
The Anatomy of the Ciliary Muscle. — Dr. A. Iwanoff has contributed a 
very valuable paper on this subject to the 11 Archiv fur Ophthal.” (Bd. xv. 
Abth. iii. s. 284-298) which is very ably abstracted in the u New York 
Medical Journal ” for March. In addition to his former researches into the 
anatomy of the ciliary muscle, contained in a previous number of the “ Ar- 
chives,” Dr. Iwanoff has undertaken to discover what differences it may 
have in myopic and hypermetropic eyes. That the difference of refraction 
involves a great difference in the accommodative function has long been 
maintained, and a corresponding variety in the ciliary muscle is to be ex- 
pected. It has been maintained that in hypermetropia the muscle would 
be found large and greater in bulk, while in myopia it would be thin and 
smaller. The examination revealed quite another state of facts. In twelve 
myopic eyes, whose axes were from 28 to 34 mm. in length, in all myopia 
being over one-quarter, there was no atrophy of the muscle, but it was 
thicker and longer than in emmetropia. The muscle is composed of two 
sets of fibres — one external and running in the meridians of the globe, 
pointed out by Bowman and Briicke ; the other set internal, at the anterior 
part circular in direction, and described by Arlt and H. Muller. In myopic 
eyes the circular fibres were almost entirely wanting, and the meridional 
fibres unusually numerous. In four hypermetropic eyes, whose axes were 
from 19 to 20 mm., the ciliary muscle was found thin and pushed forward, 
while in myopia it was thick and shoved backward. In hypermetropia, the 
posterior portion of the muscle was atrophied, the anterior part hyper- 
trophied ; that is, the circular fibres were in excess. The difference, then, 
in the structure of the muscle in myopia and hypermetropia is that in myopia 
the meridional fibres are most numerous, in hypermetropia the circular 
most numerous. 
