576 
THE PHARMACEUTICAL JOURNAL AND TRANSACTIONS. 
[January 14, 1S71, 
Introduction to the Study of Inorganic Chemistry. 
By William Allen Miller, M.D., D.C.L. Long¬ 
mans, Green and Co. 1871. 
A Laboratory Text-Book of Practical Chemistry. 
By William G. Valentin, F.C.S. John Churchill 
and Sons. 1871. 
We are really gratified in being able to announce and 
welcome these two hooks. They come to us most oppor¬ 
tunely, for they fulfil, almost as perfectly as if they had 
been compiled in that design, the desire which we have 
already expressed in the columns of this Journal. It 
has often appeared to us that the usual text-books set 
before young students of chemistry introduce far too 
much of technicality into their language and mode of 
handling the subject at the commencement; a character 
more progressive seemed to us desirable. The little in¬ 
troductory treatise now before us, the work of the late 
much-lamented Professor Miller, relieves us of a difficulty 
we have often been placed in when requested to recom¬ 
mend an elementary book. The opening chapter, de¬ 
scribing the scope and aim of chemistry, is very good; 
but our readers will gain a better idea of the style and 
plan of the work from the following extracts out of the 
short preface, than from a description of our own:— 
“ This book is written expressly for beginners. In 
order that they should really understand the statements 
which it contains, it will be necessary for them to begin 
at the beginning, and to go straight through it. Among 
other reasons for adopting this course, it is to be noted 
that it is impossible to avoid the use of technical terms 
in discussing a scientific subject; since we often have to 
deal with matters for which no expressions are in use in 
ordinary language. 
“ The student is strongly advised never to omit the per¬ 
formance of any experiment which he has the means of 
making. No useful knowledge of chemistry can be ac¬ 
quired by any one unless he constantly makes experi¬ 
ments as he proceeds with the study.” 
In this last remark we concur heartily. In order to 
indicate the methods adopted, detailed directions for up¬ 
wards of two hundred and fifty experiments, mostly of a 
simple nature, are dispersed through the book; but of 
course an intelligent lad, as he makes progress, will de¬ 
vise many others for himself. 
It is a question which may occur to some people, whe¬ 
ther it is advisable to commence so early the employ¬ 
ment of chemical notation. We are, however, of opinion 
that it is decidedly an advantage to use it, in a simple 
form, from the very first; by doing so, the precision 
which ought to characterize all scientific work is con¬ 
stantly impressed upon the mind. 
To render it complete, there should have been added 
at the end of each chapter a series of questions. We 
hope this will be thought of in a future edition. 
We have much pleasure in cordially commending this 
little volume to all who desire to acquire a solid ground¬ 
work of general principles. 
Those who wish to go a step further, and not only to 
master the fundamental principles, but to gain also an 
acquaintance with some of the details of laboratory prac¬ 
tice, will do well to choose Mr. Valentin’s ‘ Text-Book’ 
as their guide. It forms a fitting sequel to that of Pro¬ 
fessor Miller. The idea upon which it is based is the 
same. The arrangement of the book, too, is similar; 
but the student is led further. He is taught, not only 
to make experiments, but to draw from them correct in¬ 
ferences ; and from the facts which he thus learns, and the 
conclusions flowing from them, he is introduced to theory. 
Mr. Valentin, of course, makes exclusive use of the 
system of notation introduced by Dr. Erankland and 
founded upon the notion of quantivalence or atomicity. 
This system is easily intelligible. The atom of any given 
element is found by experiment to be capable of com¬ 
bining with a certain number of atoms of hydrogen or 
of any other element, chlorine for instance, which can 
replace hydrogen atom for atom. Although this number 
is apparently variable for almost all the elements, yet in 
each case there is a maximum point at which the atom 
which forms, as it were, the nucleus, is saturated. Thus- 
oxygen is certainly a dyad, because it combines with- 
either two atoms of hydrogen, or with one of hydrogen 
and one of the monad potassium, or with two atoms of 
potassium. In caustic potash the hydrogen and potas¬ 
sium are held together by the intervention of the oxygen. 
The potassium and hydrogen alone have no power to 
unite. In water the two atoms of hydrogen are linked 
by the same agency. When such an atom as that of 
oxygen, which is multivalent, is supplied with a number 
of monad or univalent atoms or their representatives,, 
which are insufficient to satisfy its combining capacities, 
the resulting group is unsaturated. It has a tendency 
to combine with other bodies wffiich may complete its 
saturation. Thus although ammonia, NH 3 , is capable 
of existing alone, it nevertheless has a tendency to com¬ 
bine with hydrochloric acid or some other body which is 
capable of completing the molecule. This is explained 
by saying that nitrogen is quinquevalent, and therefore 
is not satisfied with three atoms of hydrogen. Dr. 
Frankland distinguishes by thick typo, the element 
which in any compound possesses the greatest number 
of what he calls bonds, that is, units of combining power. 
This same element is also, as a rule, placed first in the 
formula. Thus water is written OH 2 . Carbonic an¬ 
hydride, which contains the quadrivalent element car¬ 
bon, with the bivalent oxygen, is C0 2 . Trihydric 
phosphate, or common phosphoric acid, is, by the same 
rule,: PO(IIO) 3 or POHo 3 . Dr. Frankland’s formuke 
are therefore all constitutional formula!, that is, they 
pretend to express not only the relative proportions of 
the elements in a compound, or even the number of atoms 
in the molecule of that compound, but the actual order 
in which its constituent parts are fitted together. Though 
it must be admitted there is already considerable founda¬ 
tion for such a system, it ought in the present unsatis¬ 
factory state of the science to be used with due caution 
and, we think, alternatively with one less pretentious. 
Whilst we fully admit the value of constitutional for¬ 
mulae as helps to teaching we have no sympathy with 
any of the graphic systems which have been introduced, 
and we are glad to perceive that Mr. Valentin accords 
to them quite a subordinate position in his pages. Wo 
cannot help commending very highly the arrangement 
as well as the details of this manual, and the author’s 
expressed desire to lead his pupils “to generalize and to 
systematize,” seems to be very successfully carried out. 
In the part devoted to qualitative analysis, the methods 
recommended are, we believe, both practical and accurate. 
A number of well-devised questions follow each chapter. 
In conclusion, we here record our conviction that Mr. 
Valentin’s Text-Book is the best laboratory guide to 
practical chemistry at present in existence. 
BOOK RECEIVED. 
Year-Book of Pharmacy: comprising Abstracts of Papers 
relating to Pharmacy, Materia Medica, Therapeutics and 
Chemistry, contributed to British and Foreign Journals, 
from July 1,1869, to June 30, 1870, with the Proceedings 
of the British Pharmaceutical Conference at the Seventh 
Annual Meeting, held at Liverpool, September, 1870. 
The following journals have been received:—The ‘British 
Medical Journal,’ Jan. 7; the ‘Medical Times and Gazette,’ 
Jan. 7; the ‘Lancet,’Jan. 7; the ‘Medical Press and Cir¬ 
cular,’ Jan. 11; ‘Nature,’ Jan. 5; the ‘Chemical News,’ Jan. 
6; ‘Journal of the Society of Arts,’ Jan. 5 ; ‘ Gardeners’ Chro¬ 
nicle,’ Jan. 7; the ‘Grocer,’ Jan. 7 ; the ‘English Mecha¬ 
nic,’ Jan. 6; the ‘ Chemists and Druggists’ Advocate’ for De¬ 
cember; the ‘ Chicago Pharmacist ’ for December; the ‘ Flo¬ 
rist and Pomologist ’ for Januaiw; the ‘Milk Journal’ tor 
January ; the ‘ J ouxnal of the London Institution’ for J an miry.. 
