436 
NATURE 
[ Marcu 11, 1897 
chemical properties of the new gas. Prof. Ramsay explains 
clearly the splendid initiatory work of Lord Rayleigh 
on the density of the simple gases, and then records the 
successive steps by which the disturbing element was 
tracked and isolated. Though told in the plainest way, 
this story cannot fail to prove of dramatic interest even 
to the non-scientific reader. The account of the pro- 
perties of argon, and of the difficulties which it raises in 
respect to the classification of the element, is in a more 
difficult strain than the rest of the book, and it is possible 
that a somewhat more extended treatment of the subjects 
of specific heat and the periodic law would have helped 
the general reader to a better understanding of the 
problems presented. At the same time it is right to say 
that, considering the bounds within which it is compressed 
and the difficulty of the subject, the account is very lucid, 
and it will be valuable to all readers who have some 
acquaintance with science. 
In the last few pages of the book Prof. Ramsay gives 
some play to his scientific fancy, and attempts to offer 
an explanation of the anomaly presented by argon in 
respect to the periodic law. He concludes as follows :— 
“Tt therefore appears to me not impossible that the mass 
of the atoms may be affected by the various and different 
properties which they possess, some to a greater, some 
to a lesser extent. It must be admitted that atoms 
differ from each other in the readiness with which they 
combine with those of the same kind to form molecules ; 
and that molecules of different elements differ from each 
other in their capacity to form molecular aggregates. Take 
for example such cases as cesium and fluorine, each 
intensely active, but towards different objects: caesium 
the most electro-positive of the metals, and fluorine the 
most electro-negative of elements. Surely their activity 
must be due to some cause which cannot but exert in- 
fluence on their other properties, such as their mass and 
their gravitational attraction, as it doubtless has influence 
on their specific heats and on many of their other 
physical properties. And contrast these instances with 
helium and with argon the most indifferent of substances, 
the atoms of which are unwilling to pair even with them- 
selves ; it is hardly conceivable that these peculiarities 
should leave their other, and, as we are in the habit of 
thinking, invariable, properties unaffected. I venture 
to suggest that these powers of combination, due to 
some configuration or to some attractive force, tend to 
lessen the gravitational attraction by which we measure 
their atomic weights; that helium and argon, which 
possess little, if any. of such power to combine, show 
what may be termed the normal atomic weights, inas- 
much as their gravitational attraction is subject to no 
deduction attributable to their reacting powers.” 
We cannot reproduce the considerations which lead up 
to the expression of this remarkable conjecture, and can 
therefore hardly do the author justice. Prof. Ramsay 
describes his suggestion as of a wholly speculative 
character. He expresses his “firm conviction that no 
true progress in knowledge has been made without such 
speculations.” 
With this last statement in itself we are not inclined to 
disagree ; the mind, baffled by difficulties in the paths of 
orthodoxy, may well be allowed to have its flights and 
seek more open ways, and there is a well-recognised 
scientific use of the imagination. But it is impossible to 
appraise any such speculation as the one before us, and 
we venture to think that it is rather presented as a fimale 
to an interesting story—a sort of last chapter where all 
NO. 1428, VOL. §5 | 
ends happily—than intended for scientific criticism. Prof. 
Ramsay likens it to the doctrine of phlogiston ; and cer- 
tainly the assumption of “levity” is a point of resem- 
blance. Otherwise we think the comparison unfair to 
the phlogistians. The idea of phlogiston was doubtless at 
its birth a speculation, but in science it ranks as a working 
hypothesis that guided several generations of investi- 
gators from point to point in their inquiries, that linked 
together a vast number of facts, and that even to the 
acute and sober mind of Cavendish appeared to throw as 
good a light on facts as the newer doctrine of Lavoisier. 
If Prof. Ramsay’s speculation proves fruitful, it may 
claim kinship with Becher’s ; but hardly till then. The 
author recognises this, no doubt, as ‘fully as any one. 
Meanwhile the situation between argon and the periodic 
law is not eased in any practical sense, and we are afraid 
that the book, which in many respects is an admirable 
exposition of the methods of scientific discovery, may 
prove somewhat misleading to the general reader in this 
one particular. F 
We cannot conclude this notice of a work dealing with 
the history of chemical discoveries relating to the atmo- 
sphere, without remarking upon the momentous part they 
have played in the development of chemical science. 
Viewing the discovery of argon in the light of earlier 
discoveries respecting the air, we feel that it is worthy to 
rank with the best of them, both in the manner of its 
inception and of its experimental realisation. The dis- 
covery has already raised questions of fundamental 
interest in physics and chemistry, and there seems no 
reason to believe that it will not prove as fruitful in im- 
portant consequences as any of the earlier masterpieces 
of experimental work relating to the gases of the 
atmosphere. ACtSs 
THE FENS OF SOUTH LINCOLNSHIRE. 
A History of the Fens of South Lincolnshire. By W. H. 
Wheeler. Second edition. Pp. 489, and appendices. 
(Boston: J. M. Newcomb. London: Simpkin, 
Marshall, and Co.) 
HIS book, which is nominally a second edition of a 
book published in 1868, but has in reality been 
entirely re-written and enlarged, relates merely to the 
fens of Lincolnshire, situated between the Steeping River 
and the Nene, comprising an area of 363,000 acres, and 
does not refer to the fens of Norfolk, Cambridgeshire, 
and the adjacent counties, or to the rivers Ouse and 
Nene, which, with the rivers Witham and Welland, are’ 
known as the fen rivers. In fact, the author naturally 
deals with the fen districts in his near neighbourhood, 
having resided for many years past at Boston, on the 
Witham. The history of these fens is traced back to 
the time of the Britons, and more particularly to the 
Roman settlement which was made very early in the 
Christian era; and to the Romans in the time of 
Severus, are attributed the construction of the first banks 
protecting the district from the sea, the land being from 
13 to 12} feet below the level of high-water of spring 
tides, to which probably the appellations North and 
South Holland, denoting certain portions of the fens, 
are due. Lands outside the Roman banks have been 
gradually raised by the process of warping, or accretion 
