REVIEWS. 
181 
THE CHEMISTRY OF COMMON LIFE.* 
P ROFESSOR Johnston’s “ Chemistry of Common Life ” has long been ad- 
vantageously known for its simple and familiar method of introducing 
chemical facts and reasonings to the general reader. Treating, as this work 
does, of the air we breathe ; we water we drink ; the soil we cultivate ; the 
plants we rear ; the bread we eat ; the beef we cook ; the beverages we 
infuse : the sweets we extract ; the liquors we ferment ; the narcotics we 
indulge in ; the odours we enjoy ; the smells we dislike, &c., and concluding 
with a recapitulatory chapter upon the circulation of matter, it possesses 
great interest for all who are desirous of learning something of the chemical 
and physical relations existing between themselves and the world which 
they inhabit. 
When, twenty-five years ago, “ The Chemistry of Common Life ” was 
first published, an acquaintance with the advancing science of the day was 
possessed by a very limited number only, even among the educated classes ; 
and Professor Johnston’s popular exposition of the fundamental principles 
regulating our daily life laid open to the public a new world of interest and 
speculation. In preparing the present edition for the press Professor Church 
has followed the arrangement and method adopted in the original work, and has 
made such additions and corrections only as the progress of science may have 
rendered necessary. He has, however, in the aggregate contributed much 
original matter, as well as an entirely new chapter on the colours we admire ; 
besides which many of the new analyses, and particularly those of roots, are 
either wholly or entirely the results of his personal investigations. 
The new chapter contains a notice of the red colouring matter of blood, 
now known as hcemaglobin , which contains iron, and differs from all other 
constituents of the body in various important particulars ; among the most 
remarkable of which is its property of absorbing gases. On this latter pecu- 
liarity depends one of the chief uses of the blood as a carrier of oxygen 
throughout the system. 
Another animal pigment, having a still more remarkable composition 
than that of hsemaglobin, and to which the name of turacin has been given, 
was, some years since, discovered by the editor in the pinion-feathers of ten 
or eleven different kinds of birds peculiar to Africa, and known as Touracous 
or Plantain-eaters. About fifteen feathers in each wing present patches 
which are almost entirely red, and a chemical examination of such feathers 
shows that they owe this colour to a pigment containing about eight per 
cent, of copper, so bound up with the other elements present as to be inca- 
pable of removal by any treatment short of the destruction of the colouring 
matter. The existence of an animal pigment so rich in copper is an exceed- 
ingly curious and interesting fact, but one of which the whole history is still 
far from being thoroughly understood. 
The black feathers of some birds, black human hair, and, possibly, the 
skin of certain mammals likewise contain a dark pigment capable of resist- 
ing the action of tolerably strong sulphuric acid. Sorby obtained one 
* “ The Chemistry of Common Life,” by the late James H. W. Johnston, 
F.R.S.S. L. <fc E., &c., a new edition brought down to the present time. 
By Arthur Herbert Church, M A., Oxon. 8vo. Edinburgh and London : 
Blackwood & Sons. 1879. 
