APRIL 16, 1914| 
NATURE 
161 
which are pouring pus into the buccal cavity may 
be estimated, at least has been estimated, at 
200,000.000.”’ 
Chap. ii. contains a fairly wide description of 
the function of mastication, and of the effects of 
saliva on various foods. Chap. ili., on ‘Children 
and Dental Disease,” is to a large extent a repeti- 
tion of parts of chap. 1i., but clothed in different 
language. 
We do not consider these chapters are a serious 
contribution to the literature of public health. 
Careful perusal of them impresses upon us the 
conclusion that, while condemning physiologists 
and medical men for their shortcomings in dental 
hygiene, the author is unduly confident in his own 
exaggerated and unbalanced opinions. He recom- 
mends prevention of dental disease by methods of 
dieting, which “show beyond all doubt that dental 
caries is not only preventable, but that it is easily 
and surely preventable.” 
The enormous benefit bestowed by early treat- 
ment as a method of prevention is not admitted 
by the author, who asserts that, “compared with 
modern methods of prevention, however, treatment 
must be regarded as a failure.” He is equally 
clear that sugar should not be regarded as a whole- 
some and cheap food for children, but as a large 
and important factor in the production of dental 
caries. In these opinions we doubt if many 
physiologists will join him. 
Savants du Jour: Albin Haller, 
Bibliographie Analytique des Ecrits. By Ernest 
Lebon. Pp. 120. (Paris: Gauthier-Villars ; 
Masson et Cie., 1913.) Price 7 francs. 
THERE is something to be said for the publication 
of a man’s biography during his lifetime. He is 
at least able to participate in the pleasant things 
that are said of him. Mr. Ernest Lebon has 
undertaken the task of writing the lives of the 
“Savants du Jour,” and so far he has completed 
seven, the latest of the series being the life of 
Prof. Albin Haller. Son of a joiner and cabinet- 
maker, of Thaun-St.-Amarin, in the Vosges, 
Haller was apprenticed to a local apothecary until 
the outbreak of the Franco-German War, when 
he served as hospital assistant. At-its conclusion 
in 1871, he left his native town to follow the 
fortunes of his teacher, M. Gault.. When the 
staff of the Strasburg University was transferred 
to Nancy, Haller entered as a student of phar- 
macy, and in 1873 became lecture assistant in 
chemistry. He quitted the school of pharmacy in 
1884 in order to fill the chair of chemistry. He 
was elected corresponding member of the Academy 
of Sciences, in 1891, and in 1899 was asked to take 
the chair vacated by the death of Prof. Friedel 
as professor of organic chemistry at the Sorbonne. 
In 1911 he was made commander of the Legion of 
Honour, and since then he has received wide- 
spread recognition by native and foreign scientific 
bodies. 
His principal researches are mainly in the 
domain of organic chemistry. 
In connection with his studies in the camphor 
group, he not only obtained a great variety of 
NO. 2320, VOL. 93] 
Biographie, 
| 
new and interesting derivatives of camphor and 
borneol, but among them the homologue of cam- 
phoric (homocamphoric) acid, which on distillation 
of its lead salt gives camphor, and in this way 
he succeeded in effecting a partial synthesis of 
camphor. The long list of researches which have 
emanated from his laboratory, in addition to his 
numerous literary contributions on scientific sub- 
jects, give evidence of an unusually active and 
fruitful career. EE Be 
A Course of Practical Work in the Chemistry of 
the Garden. By D. R. Edwardes-Ker. Pp. 
40.- (London: -John Murray, 1914.) . Price 
1S._ 6d... nee 
One of the results of the foundation of a diploma 
in horticulture by the Horticultural Society is 
certain to be an improvement in the method of 
education of horticultural experts. The number 
of appointments in this direction tends constantly 
to increase, and now that the Board of Agriculture 
has established a horticultural branch, the com- 
petent expert finds the possibility before him of 
a highly successful career. In order to meet the 
demand for text-books that is certain to arise, 
Mr. Edwardes-Ker has collected a set of experi- 
mental lessons to be carried out in a chemical 
laboratory, and requiring only such limited know- 
ledge of chemistry and of manipulation processes 
as will be available in the circumstances. 
The book is divided into four chapters, headed 
respectively, ‘“‘The Chemistry of Plants,” “The 
Chemistry of Soils,” ‘‘The Chemistry of Manures 
and Fertilisers,” and “‘The Chemistry of Sprays 
and Washes.” The experiments are simple and 
well chosen, and should prove of distinct value 
both to the student and the teacher. They will, 
of course, require to be supplemented by a suit- 
able series of lectures setting forth the bearing 
of the facts thus ascertained on the growth of 
plants, and, in order to bring this out more 
clearly, we should like to see some pot expert- 
ments added. Pot experiments can be made 
quite simple enough for the purpose, and satis- 
factorily demonstrate many important phenomena 
that laboratory exercises alone can never bring 
out. 
A Practical Manual of Autogenous Welding (Oxy- 
Acetylene). With a chapter on the Cutting of 
Metals with a Blowpipe. By R. Granjon and 
P. Rosemberg. Translated by D. Richardson, 
Pp. xxiit+234. (London: C. Griffin and Co., 
Litd:, 19Eg.\yiPeice, Gs. net, 
Autrocenous welding consists in uniting metals by 
fusion without the intervention of solder. Ordinary 
welds may be effected by heating in a forge, but 
the local application of heat by an electric current 
or by the heat of an intense flame is more pro- 
perly called autogenous welding in contradistinc- 
tion to the junction of metals made by solder. 
The work before us treats of welding as done by 
the oxy-hydrogen and oxy-acetylene blowpipe, the 
introductory matter on soldering and electric 
welding being outside the main purpose of the 
work. The oxy-hydrogen weld was used before 
oxy-acetylene, but the latter is now the most 
