Fan. 5, 1882] 
NATURE 
228 
requisite in erder that the charge should be retained for 
a sufficient time to be practically available. 
The rapidity of loss during repose will depend upon 
the closeness of the sulphate of Jead and perhaps upon 
other mechanical conditions. These are doubtless sus- 
ceptible of great modifications. We do not know how 
far they are modified in practice, but it is conceivable 
that still greater improvements may yet be made in this 
direction. J. H. GLADSTONE 
ALFRED TRIBE 
STEUDEL’S NOMENCLATOR 
AEE working systematic botanists use Steudel’s 
“Nomenclator botanicus seu Synonymia_plan- 
tarum universalis’’? as an indispensable book of refer- 
ence. It is an alphabetical list arranged under genera of 
published names of plants, giving their native countries 
and the authors who published their descriptions. Sy- 
nonyms are as far as possible given under the species to 
which they belong. The second volume of Steudel’s 
work was published in 1841, and it is probably not far 
wrong to assume that the existing mass of described 
plants has since doubled. 
Mr. Darwin has with equal kindness and generosity 
expressed the wish to aid in some way the scientific work 
carried on at the Royal Gardens, Kew. 
been made for many years to keep up in the herbarium 
there a copy of Steudel with manuscript additions, for the 
use of persons engaged in the study of any particular 
group of flowering plants. By reference to the Kew 
Steudel it is possible to ascertain to a large extent what 
has been done, and so avoid the risk of describing and 
naming the same material twice over. But the Kew 
Steudel has only hitherto been posted up by the aid of 
funds privately supplied on intermittent occasions, and is 
not absolutely complete. 
Mr. Darwin having had occasion to appreciate the use- 
fulness of such a work in the botanical investigations 
which have of late years engaged his attention, has deter- 
mined to supply the funds for preparing a new edition of 
Steudel’s ‘‘ Nomenclator,’ brought up to date. The 
work, which it is estimated will extend over about six 
years, will be carried on at Kew, and will be based on the 
limitations of genera laid down in Benthamand Hooker’s 
“Genera Plantarum,” to which it will in fact form a kind 
of complement. The editorial work has been entrusted 
to Mr. Daydon Jackson, Secretary of the Linnean 
Society. Mr. Darwin’s munificent aid does not extend 
beyond supplying the means for preparing the work. 
The form and manner of publication will be reserved for 
consideration on its completion. 
The Royal Gardens, Kew, have been very fortunate 
in from time to time receiving sympathetic aid from 
the outside world on behalf of the various branches of 
scientific work carried on in connection with them. The 
gifts of Mr. Bentham’s library and herbarium, of the 
Jodrell Laboratory, of the North Gallery, and now of the 
means of preparing a new Steudel, are conspicuous 
examples. 
FIRE RISKS OF ELECTRIC LIGHTING 
IX an article published originally in the United States, 
and reprinted in our contemporary, the Chemical 
Vews, Prof. Henry Morton has called attention to the 
risks to which property is exposed from the increasing 
employment of powerful currents of electricity for electric 
lighting. The caution and the remedies suggested are 
assuredly timely when preparations are being made on so 
many hands for a vast extension of electric lighting. No 
fewer than five times did fire break out in the late Paris 
Exhibition, and in each of these cases the cause was the 
same, namely, defective insulation of the conducting 
The attempt has | 
wires. Prof. Morton divides the dangers into two kinds 
—those arising from the conductors, and those arising 
from the lamps. When naked wires are used as con- 
ductors, and when both are, as is sometimes the case, 
merely nailed or stapled to wall or floor side by side, 
there is a great chance that some stray scrap of wire, a 
falling nail or pin, may short-circuit the line and become 
red-hot in an instant. Loose wires are again a source of 
danger, as they may be momentarily short-circuited, and 
arcs set up of a dangerous nature at the point of contact. 
These remarks are specially cogent in such cases as those 
where many arc lights are being worked on a single 
circuit, and where there is of necessity a very high electro- 
motive force employed. On such circuits, moreover, 
should some of the arcs go out, there is a risk of the 
others becoming excessive in power, risking the metal- 
work of the lamps, and thereby endangering a conflagra- 
tion. Moreover, the lamps themselves are not free from 
danger, if so constructed that fragments of red-hot carbon 
can fall from them, as was the case not many months 
ago with one of the Siemens’ lamps in the reading-room 
of the British Museum. 
As a remedy to diminish such risks, Prof. Morton 
makes the following recommendations, every one of 
which we can heartily indorse. Firstly, that both the 
conductors—the outgoing main and the return wire as 
well—should be completely insulated; and that the 
machines and fixtures of the lamps should also be insu- 
lated, so far as regards all ground connections. Secondly, 
that the outgoing and return wires, instead of being laid 
side by side, should be separated as widely as possible. 
And he also recommends that, in the case of arc lamps 
in series, there should be automatic adjustments, to short- 
circuit a part of the current in case the arc in the lamp 
becomes too powerful, and to diminish the electromotive 
force of the generators in proportion to the actual resist- 
ances in circuit. Even on those systems of electric 
lighting which apply the principle of incandescence, 
where the electromotive forces employed are, as a rule, 
smaller than with arc lighting, there is need of caution. 
And one cannot too highly admire the ingenious device 
with which Mr. Edison has met most of the possible ob- 
tions beforehand, by interposing automatic ‘cut-off ” 
joints of lead wire at every branch of the ramified circuit 
of his system of supply ; the thickness of the wire being 
adjusted according to the circumstances of each case. It 
would be well for Fire Insurance Companies to lose no 
time in laying down a code of reasonable conditions to 
be complied with in case of buildings lit by electric lights. 
Without such precautionary conditions electric lighting is 
at Jeast as unsafe as lighting by gas, and that is saying a 
good deal. But where proper precautions are taken, we 
think it should be a far safer mode of lighting; and 
should be recognised as such by the imposition of a lower 
insurance premium than is fixed in the case of lighting 
by gas. 
THE MARKINGS ON FUPITER 
URING the present winter months Jupiter will 
doubtless attract a large amount of attention from 
the possessors of telescopes. Displaying a large and 
varied extent of detail clearly indicating that atmospheric 
phenomena of stupendous character are in progress on 
his surface, this planet at once claims notice on account 
of the ease with which his chief features may be di- 
scerned, and their singular anomalies of motion and 
appearance made manifest. 
The large red spot situated immediately south of the 
great southern belt, and lying parallel with it, continues 
to present a well-defined boundary, indeed we must 
attribute to this remarkable formation a good deal of 
| the interest which has been accorded to this planet since 
; the first apparition of the spot in the summer of 1878. 
