336 
Analyses of Books. 
[May, 
physiological and pathological fluids. The author not merely 
treats of speCtroscopic examination as a means of detecting and 
recognising blood-stains, but gives an account of the changes 
produced in the blood by a variety of agencies. Thus we have 
a description of the speCtrum of the blood in death from as- 
phyxia ; in death from the inhalation of nitrous oxide, and ot 
carbonic oxide ; the spearum of blood treated with nitrogen 
dioxide, with sulphuretted hydrogen, with hydrocyanic acid and 
soluble cyanides. The author next explains the effect upon the 
blood of nitrites, of ammoniacal gas, of arsenic and antimomc 
hydrides. The use of such investigations in questions ol medi- 
cal and chemical jurisprudence may fairly be pronounced the 
smallest part of their value. Bile and urine are next dealt with 
in a similar manner. 
It may doubtless be asked why the spectroscope has not 
already become one of the recognised auxiliaries of the physician, 
seeing that it will frequently be of signal use in the diagnosis ot 
disease, in the comprehension of morbid changes, and in tracing 
them to their cause ? , 
The author considers that many practitioners have been de- 
terred from the use of this instrument by exaggerated ideas ot 
the difficulties involved, and by the want of a simple treatise on 
its use and on its applications to Physiology and Pathology. 
Many persons still living will remember the time when the mi- 
croscope was regarded with a similar distrust, which has only 
gradually — and we may say not entirely — been got rid of by the 
appearance of practical works on microscopic manipulation. 
Such wants, as regards the spectroscope, the author makes it 
his business to supply, and in our opinion with very marked 
success. In the two introductory chapters he explains the essen- 
tial parts of a spectroscope, the various kinds of speCtia, the 
nature and use of the one- and two-prism chemical spectroscope, 
the art of mapping speCtra, the nature of absorptive as distin- 
guished from bright-line speCtra, and the. use of the micro- 
speCtroscope. A supplement gives the bibliography of medica 
and physiological speCtroscopy. . . 
This work merits the attention not merely of the physician 
and the medical student, but of the toxicologist, and of all who 
engage in biological research. To all of these classes a. fami- 
liarity with the use of the spectroscope is like the possession ot 
an additional sense, and in acquiring such familiarity they will 
find Mr. MacMunn’s treatise a needful guide. We hope it will 
enable many aspirants to qualify themselves for research in the 
fruitful field which Mr. Sorby has cultivated with such success. 
It must be distinctly remembered that the author is not a mere 
compiler, having no special and practical acquaintance with the 
subject of which he treats, but an aCtual and experienced 
observer. 
