360 
Nottingham are excellently illustrated in vol. xxv., 
part 2. In this last part, moreover, H. Dewey and 
R. A. Smith sustain the view that the sequence of 
Palawolithic culture at Swanscombe, in Kent, is 
identical with that established in France and Belgium. 
The publications of local societies also bear witness 
to the activity of geological observers, and especially 
of the amateurs who add so much to scientific know- 
ledge in England. H. C. Beasley thus continues 
the description of the remarkable Triassic footprints 
at Storeton (Proc. Liverpool Geological Society, 
vol. xi., part iv.), and D. Woolacott furnishes an 
important paper on the stratigraphy and tectonics of 
the Permian of Durham (Proc. Univ. of Durham 
Philosophical Society, vol. v., part 5). 
.THE recent memoirs of the Geological Survey of 
Great Britain, each of which describes a sheet of the 
series of colour-printed maps, include ‘‘The Country 
‘around Newton Abbot,’? by W. Ussher and other 
authors, and ‘“Fareham and Havant,” by “Hl J. 0: 
White. In the former, Clement Reid confirms Heer’s 
correlation of the Bovey Tracey Beds with continental 
representatives now classed as highest Oligocene. The 
map (Sheet 339) includes the edge of the Dartmoor 
granite, and the seaside resorts of Exmouth, Dawlish, 
and Teignmouth, and, with the memoir, should be 
of great service to visitors in this very varied region. 
The Havant map and memoir pleasantly continue the 
series devoted to the Downs and the Cainozoic synclines 
of south-eastern England. Scotland furnishes Memoir 
and Sheet 82, on Central Ross-shire, and Memoir and 
Sheet 92, on the Fannich Mountains and Strath 
Broom.’ The names of B. N. Peach and J. Horne 
appear among the authors of both these publications, 
which deal with wild districts of pre-Cambrian and 
Cambrian rocks. Despite their moderate price (2s. 3d. 
and 2s. 6d.), both works are illustrated with land- 
scapes which are chosen with the eye of a geologist, 
but which will equally delight any lover of the high- 
lands. The many students of thrust-structure and 
mountain-building will find new diagrams and new 
material in both these interesting memoirs. 
’ 
‘Tye Oil Resources of the Empire’ formed the 
subject of an address by Dr. F. M. Perkin, recently 
delivered before the Society of Arts, and published in 
the Journal of the society (vol. Ixii., No. 3204). It is 
not generally realised how vast is the consumption of 
mineral oils in the United Kingdom, and how small 
a proportion is supplied from within the Empire itself. 
Out of a consumption of more than four million 
gallons only 2-67 per cent. was derived from British 
sources. It is hoped that by systematic surveys new 
sources of supply may be located, and valuable sources 
of oil may in future be found in the great shale beds 
of Tasmania. Much, too, remains to be done in in- 
creasing the supply of vegetable oils, more particularly 
of linseed oil, which might with advantage be pro- 
duced extensively on British soil. One of the most 
striking features of recent years has been the rise of 
the soy oil industry, and in view of the fact that the 
crushing industry has now fallen largely into Japanese 
hands, it is suggested that attempts. should be made 
to cultivate the soy plant in British territory. 
NO, (2327, ViOLeagail 
NATURE 
[JUNE 4, 1914 
AMONG recent American papers on the chemistry of 
soils the following may be noted. Mr. G. W. Wilson, 
in the Biochemical Bulletin (vol. ii., No. 10), reports 
a series of experiments on the effect of heating the 
soil on plant growth. It appears that heating the 
soil to a temperature of 95° C. caused slight accelera- 
tion of growth, but a higher temperature (135° to 175°) 
brought about a marked retardation; plants grown 
on the heated soil were more susceptible, however, to 
attack by parasitic fungi. In the same number of the | 
Biochemical Bulletin, Mr. A. W. Thomas gives a 
convenient summary of the methods adopted by 
Schreiner and Shorey for isolating and detecting 
arganic soil constituents, whilst in the Journal of 
Agricultural Research (vol. i., No. 5, p. 357) Mr. E. C. 
Shorey describes the isolation of certain derivatives of 
benzene from samples of sandy soil from Florida at 
present devoted to orange culture. These compounds 
were benzoic acid (350 lb. per acre foot), metahydroxy- 
toluic acid (800 Ib.), and vanillin (40 Ib.), of which the 
latter at least appears to exist in the soil in the free 
state, probably being an unchanged residue of plant 
débris. 
VoL. Ltxvu. of the Annalen der Physik contains an 
important series of four papers, one by Prof. Stark 
alone, and three by him in cooperation with others, 
on the effect of electric fields on spectrum lines. 
Since the discovery of the magnetic change of radia- 
tion frequency by Zeeman, various physicists have 
tried to discover an analogous electric effect. Prof. 
Stark has succeeded in affecting the spectrum lines 
emitted by canal rays in a vacuum tube by submitting 
them to an electric field, ingeniously arranged between 
a perforated kathode and an auxiliary electrode at 
a few millimetres’ distance. The field intensity 
amounts to 30,000, and in some experiments even to 
47,000, volts per cm. When the observation is made 
at right angles to the field, the spectrum lines are split 
up into polarised components under the action of the 
field, which proves to be rather homogeneous. The 
separation of the components is proportional to the 
field intensity. The hydrogen, helium, and lithium lines 
are studied in detail. For the line Hg (4861 A.U.) the 
separation of the outer components, which vibrate 
parallel to the field, becomes about 8 A.U. in a field 
of 28,500 volts per cm. In a direction parallel to the 
electric field the components of the resolved lines are 
unpolarised. The analogy between the Zeeman effect 
and the electric effect consists in the spectrum lines 
being resolved by both kinds of fields; but in all 
details there are great differences. The magnetic 
resolution is, with some limitations, the same for all 
lines belonging to the same spectrum series, and it 
decreases toward the violet end of the spectrum. The 
electric resolution is different for succeeding lines of a 
series, and the effect increases with decreasing wave- 
lengths. Diffuse lines are most strongly affected by 
the electric field. The two yellow sodium lines show 
only a very small electric effect. The mechanism of 
the magnetic effect is certainly understood in its main 
features, but the exact meaning of the electric effect is 
still obscure. 
Last week’s Times Engineering Supplement con- 
tains an excellently written article by Prof. J. A. 
