EE VIEWS. 
355 
observer : with it be collects tbe rays of light from the condenser or chamber 
of lenses, and throws them on to the laryngeal mirror ; this in its turn reflects 
them to the larynx ; from it they again travel to the mirror ; and from this they 
then pass to the observer’s eye. Those portions of Dr. Mackenzie’s work 
which relate to the healthy and morbid characters of the larynx and vocal 
cords display much careful research, and though of little interest to the non- 
professional reader, will be read with considerable advantage by the laryn- 
goscopist. His chapters on the surgical operations for the removal of 
unhealthy growths, tumours, &c., are equally important. 
The little brochure of Dr. Johnson contains a report of two lectures which 
this gentleman delivered at the Eoyal College of Physicians. Although 
the subjects it treats of are those which Dr. Mackenzie has dealt with in his 
larger volume, still they are presented to the reader in a somewhat different, 
and, if comparisons were not “ oderous,” we should say in a more familiar 
style. He points out the truth of what we have already stated ; viz., the 
difficulty which heretofore attended the diagnosis of throat diseases. Quoting 
from Mr. Porter, who wrote in the year 1837, he writes, — “ How is a man of 
experience, when he meets with a case of laryngeal disease, to know whether 
it is caused by an oedematous condition of submucous tissue, by the presence or 
absence of tumour, or by any other of these numerous afiections which dis- 
section so frequently shows us to be the occasion of death ?” WeUmay he ask 
how. Indeed, till the employment of the laryngoscope, the answer invariably 
was, by no means whatever. There is one feature in Dr. J ohnson’s little book 
which deserves notice. A series of illustrations are given showing the relative 
positions of physician and patient during laryngeal examination. This is of 
much' advantage to the student, and we think it is to be regretted that 
Dr. Mackenzie did not adopt a similar mode of illustration, for in his work, 
although the woodcuts are in point of execution the highest of their class, 
still they present in most cases portions of the apparatus, and in no instance 
have the entire apparatus with the patient and laryngoscopist been displayed 
together. We think too that in one instance there is some mistake as to the 
operation of lenses upon light ; most probably, however, the error is one of 
the printer’s. In page 45 of Dr. Mackenzie’s treatise we find it stated, “ that 
since, when rays fall on a convex surface, a certain number are refracted and 
do not pass through it, the plane face of a plano-convex lens should be placed 
next the flame.” We presume that the word reflected was intended, as 
otherwise the meaning of the sentence is by no means clear. Both essays, 
however, are exceedingly good, and we commend them to the careful con- 
sideration of those who desire to know how to work with the laryngoscope. 
They are clearly written, abundantly illustrated, and as regards type, paper, 
and mechanical details, are excellent. 
MICEOSCOPIC ANATOMY.* 
T hose who are conversant with the progress of human Histology 
during the past five years are aware how much the labours of Dr. 
Lionel Beale have contributed to the advancement of this department of 
* “ On the Structure and Growth of the Tissues,” &c. By Lionel S. 
Beale, M.B., F.E.S. London : Hardwicke. 1865. 
VOL. IV. EO. XV. 2 B 
