JANUARY 3, 1907] 
NATURE 229 
With regard to the naming of plants of Lessonia re- 
ceived from the Antarctic region, Mr. and Mrs. A. Gepp 
note in the Journal of Botany (December, 1906) that 
anatomical investigation discloses a distinction between the 
specimens from Cape Adare and Coulman Island and that 
from the South Orkneys. The former 
of Lessonia grandifolia, the latter L. simulans. 
receives the name 
In vol. xvi. of the Transactions of the South African 
Philosophical Society is a paper by Mr. L. Péringuey on 
petroglyphs of animals and men in South Africa con- 
sidered in relation to those found in northern Africa. He 
points out that two kinds of workmanship are found in 
Algeria and the Sudan—line engraving and dot engraving, 
the former being apparently much older, as prehistoric 
animals now extinct, such as Bubalus antiquus, are re- 
presented with great fidelity. Similar differences of tech- 
nique exist in South Africa, and the author argues that 
they afford evidence of a pre-Bushman race akin to the 
aborigines of the north; but he is evidently a zoologist, 
not an anthropologist, and it is clear that more material 
is needed for comparison, as well as definite archzological 
data, before the views set forth in this paper can rank as 
Rock engraving (chalked to show clearly) of a Gemsbok checking itself 
while at full speed. 
more than mere conjectures. The article is well illus- 
trated by ten figures, of which one is reproduced here; the 
author remarks that it represents a gemsbok checking 
itself at full speed before an object intended to alarm it, 
but it does not seem necessary to assume more than a 
chance connection between the figures. The petroglyphs 
were chalked over for photographic purposes; this intro- 
duces an element of uncertainty which it would be well 
to eliminate. 
On the subject of diseases of palms, Mr. E. J. Butler 
contributes a paper to the Agricultural Journal of India 
(vol. i., part iv.) recording three diseases that have come 
under his observation in India. In the first case the in- 
florescences of betel-nut palms were destroyed by a Phyto- 
phthora causing what is locally known as “‘ kale roga”’ 
or black rot; in another a bud-rot disease of palmyra and 
cocoa-nut palms in the Godavari district was traced to a 
Pythium. The so-called betel-nut plague occurring in 
Sylhet was more difficult to diagnose, but the author refers 
it definitely to a fungus attacking the roots, and the clamp- 
connections in the mycelium point to its being a basidio- 
mycete. Detailed descriptions are given and remedial 
measures suggested. 
NO. 1940, VOL. 75] 
Tue latest addition to the series of German pamphlets 
on the pedagogics of the natural sciences published by 
P. G. Teubner, of Leipzig, deals with the subject of a 
scheme for teaching nature-study in schools. The author, 
Dr. P. Henkler, reviews several schemes 
masters of pedagogy and instructors in natural history 
before elaborating his own syllabus. During the first stage, 
for small children, extending over three courses, it is sug- 
gested that interest in natural objects should be aroused by 
imaginative or personified presentment, and observation 
be coordinated with facts of everyday life. In the second 
stage, botany and zoology would be taught as independent 
subjects, the essential idea being to stimulate the faculty 
of inquiry by studying purpose and cause. 
advocated by 
Mr. Matcorm Burr has written, for the Kent Coal 
Concessions, Ltd., a popular introduction to the study of 
the geology of the south-eastern coalfield. It contains in 
simple language a concise explanation of the principles of 
geology sufficient to enable shareholders to follow intelli- 
gently the significance of the various borings carried out 
under the auspices of the company. 
In the Engineering Magazine (vol. xxxii., No. 3) there 
is ay admirably illustrated article by Mr. Frank L. Hess 
on the York tin region of Alaska, where lode tin was dis- 
covered in 1903. Should the lode deposits be shown to 
contain sufficient tin to pay for working, they will have 
many advantages over placer deposits, inasmuch as mining 
would not have to be confined to the short open season. 
Tue Transactions of the Institution of Engineers and 
Shipbuilders in Scotland (vol. 1., part ii.) contains an 
interesting paper by Mr. Hugh Campbell on suction gas 
engines. The introduction of the suction gas plant, in- 
vented in 1894, is causing a greater revolution in practice 
than has occurred in connection with the development of 
large gas engines, which are mainly used at the present 
time in conjunction with blast-furnace gas. Its very high 
economy, extreme simplicity, its cleanliness, and the small 
amount of space it occupies are sufficient to commend it 
to power users. 
A paper read by Mr. Henry Fowler before the Institution 
of Mechanical Engincers on December 14, 1906, dealing 
with the lighting of railway premises, contained much in- 
formation of value to engineers generally. The lighting 
on a railway is chiefly provided by means of oil, gas, or 
electricity, gas being probably the most general illuminant. 
In most places it has been able to hold its position owing 
to the introduction of incandescent mantles. The cost of 
maintaining an incandescent mantle for a year to June, 
1906, is shown to have been as follows :—mantles 5-20d., 
chimneys 1-27d., forks 0-33d., and wages 1s. 416d. per 
annum. 
IN a recent note (p. 181) attention was directed to the 
recent renewal of experiments with Count Zeppelin’s latest 
airship on the Lake of Constance. An account of these 
new experiments is given by Dr. Wilhelm Krebs in Das 
Weltall for December 15, 1906. The 1906 Zeppelin air- 
ship, like its forerunners, consists of eighteen separate 
compartments or separate” balloons supported on a rigid 
cylindrical aluminium framework, the whole being encased 
in a covering of balloon silk. The rigidity being secured 
by the framework, the use of an internal ‘‘ ballonet ”’ is 
dispensed with. The whole airship is 128 metres long by 
11 metres high, and each of the two cars can hold four 
persons, besides having a separate motor. The author 
states that with both motors working simultaneously a 
