20 
NATURE 
[Mov. 3, 1870 

its length until shaped to the sizerequired, Axles of any length 
could be rolled by the machine, with collars at any part of the 
tyre. The rollers were geared to revolve all in the same di- 
rection, and their friction imparted motion to.the axle. The 
rolling process would obviate those flaws in axles which occa- 
sionally caused appalling accidents on railways. 
On a New Safely Lamp.—My. W. E. Teale. After detailing 
a number of the objectionable features of the various safety lamps 
now in use, the author proceeded to say that, with a view to 
remedy so far as possible the dangers arising from the insecurity 
of the present oil lamps, the Protector Colliery Lamp has been 
carefully and thoughtfully designed to combine safety and bril- 
liancy of light with cleanliness and economy. It is madeon the 
principle of the ordinary sponge or portable gas lamp, in which 
is used a liquid specially prepared by the inventors. The reser- 
voir, or gas-holder, is then screwed to the top of an ordinary 
Stephenson or Clanny lamp, within which are fixed a pair of 
horizontal hinges, moving upwards only. On the wick tube of 
the lamp, and sliding over it, is an outer tube, having round its 
centre a circular horizontal flange. When the reseryoiris screwed 
upwards into the top, this flange comes into contact with the 
hinges, raises them in passing, and allows them to fall beneath it 
when screwed home, so that by reversing the screw, and with- 
drawing the reservoir gradually from the top, the said hinges 
prevent the return of the said sliding tube, thereby forcing it over 
the wick-tube, and so diminishing, and ultimately extinguishing 
the light. It is therefore impossible for a naked light to become 
exposed after the lamp has once been adjusted. ‘To render se- 
curity doubly sure, a lock and stop are so placed that after the 
light is put out by the action of the screw, it is still impossible 
for the collier to withdraw the reservoir from the top, so as to 
re-light his lamp. The safety of the mine is further insured by 
the fact that the gauze is kept perfectly clean, and therefore no 
coal-dust can adhere to it, as in the old oil lamps. In regulating 
and reducing the light when testing for gas, which can be done 
with the greatest ease and certainty, no pricker is used or required, 
and another source of danger is avoided. This lamp burns freely 
with less ventilation than any now in use, and is much more 
sensitive to the presence or action of gas, while it is impossible 
for the miner to light his pipe from, or tamper with, the light in 
any manner. It gives much more light than that produced by 
the very finest oil; and as neither smoke nor soot is made by 
combustion, the glass and gauze are as clean and the light as 
good at the end of the day as when the miner goes down the pit, 
and this without the trouble and great loss of time necessary to 
keep an oil lamp properly trimmed. As compared with oil, the 
cost of burning the Protector Colliery Lamp is very small, six 
days of ten hours each, or sixty hours, being obtained at a cost 
of threepence, or less than one half the price of ordinary miners’ 
candles, and one-third that of the usual oil. 
On Ocean Telegraphy.—Captain Rowett. The object aimed 
at in his paper by Captain Rowett was to show the superiority of 
hemp over metallic cables. The author contended that hemp 
cables were much lighter and extremely enduring when sub- 
merged, and iron cables were quickly corroded by the action of 
the sea water. Various specimens of submerged cable were ex- 
hibited by the author in support of his views. 


SCIENTIFIC SERIALS 
Fournal of the Chemical Society, September, 1870.— This 
number only contains two papers ; the first, on Vapour Densities, 
by Mr, J. T. Brown, contains a short description of the methods 
that have been proposed for their determination, and the 
formulze employed for calculating the results from the data 
obtained. This serves as an introduction to a series of elabo- 
rate tables intended to facilitate these complicated calcula- 
tions. The tables are a sequel to some previously published 
by Mr. Brown (Fourn. Chem. Soc. N.S. iv. 72), and it might 
be acceptable to many chemists if the author would collect 
these and other tables and publish them in a separate pam- 
phlet. The other paper is an abstract of a memoir in the 
Philosophical Transactions for 1869, entitled ‘‘ Researches on 
Vanadium,” by Professor Roscoe. The author has obtained 
three vanadium chlorides, a tetrachloride V Cl,, a trichloride 
V Clg, and a dichloride V Cl,. The tetrachloride may be pre- 
pared by passing dry chlorine over the mononitride heated to 
redness, or by transmitting a mixture of chlorine and the vapour 
of vanadyl trichloride V O Cl, over red-hot sugar-charcoal. Its 

vapour density corresponds to the formula V Cly. The tri- 
chloride is a crystalline peach-blossom coloured compound, re- 
sembling chromium sesquichloride. It is not volatile in 
hydrogen, but when strongly heated in this gas it loses 
chlorine, the dichloride and finally the metal being obtained. It 
is produced by heating the tetrachloride, or by its slow decom- 
position at the ordinary temperature, or by passing its vapour 
with hydrogen through a red-hot tube. Vanadium dichloride is 
an apple-green crystalline body, prepared by transmitting the 
vapour of the tetrachloride with hydrogen through a tube heated 
to dull redness. The dichloride, when heated in hydrogen in 
a platinum boat, yields the metal in bright, greyish-white 
lustrous grains. The processes hitherto described for the prepar- 
ation of the metal have been tried by the author without success. 
The chloride or nitride is placed in a platinum boat and heated 
in a porcelain tube, through which a current of pure hydrogen 
passes. The metal does not tarnish in the air at common tem- 
peratures, but burns with brilliant scintillations when thrown into 
aflame. When heated in air it oxidises, producing all the oxides 
Vo. O, Vz Og, Ve Og, Vz Oy, and V, O;. It is not attacked b 
hydrochloric acid or dilute sulphuric acid. Hot strong sulphuric 
acid slowly dissolves it.. It is violently oxidised by nitric acid, 
and slowly dissolved by hydrofluoric. The metal burns in chlo- 
rine, and when heated in nitrogen forms the mononitride. 



DIARY 
THURSDAY, NovemMBeER 3. 
Linnean Soctety, at 8.—On the Fertilisation of Orchids and Asclepiads : 
Dr. Manse! Weale.—On a Solitary Bee from South Africa: Dr, Mansel 
Weale. 
CueEmIcAL Society, at 8.—On the Analysis of Cast-iron: Mr. A. H, Elliott. 
MONDAY, NovemBer 7. : 
Roya INstiTuTION, at 2.—General Monthly Meeting. 
Lonpon InsTITUTION, at 4.—Chemistry: Prof. Odling. 
TUESDAY, NovemeBer 8. 
ETHNOLOGICAL Society, at 8.--On the Kimmerian and Atlantean Races : 
Mr. Hector McLean —Note on the name ‘“‘Aymara”: Mr. C. R. Markham. 
—Reply to Mr. Markham’s Note by Mr. David Forbes. 
WEDNESDAY, NovemBER 9. 
Royat Microscoricat Society, at 8.—Notes on the Minute Structure of 
certain Insect Scales: Mr. S. J. M‘Intire 
THURSDAY, NovemBER to. 
Lonpon MatHematicat Society, at 8.—General Meeting. Retiring Pre- 
sident’s Address. Sketch of recent researches upon quartic and quintic 
surfaces. 



BOOKS RECEIVED 
EncGiisu.—The Elements of Mecha: ism: T. M. Goodeve (Longmans).—~ 
Papers on the Great Pyramid: J. V. Day (Edmonston and Doug as). . 
ForeiGn.—{Through Williams and Norgate)—Jahrbuch der Empfindun- 
gen: Hirzel und Gretschel.—Geometr sche See-proben; Dr. Boet:cher,— 
Ueber aie Entwicklung und Verwendung der Warme: P. Tunner.—Archiv 
fiir Ophthalmologie}: Arlt, Donders, und von Graeffe.—Jahresbericht itiber 
die Fortschritte der Chemie. 


CONTENTS Pace - 
Tue GOVERNMENT OF THE RoyAL SOCIETY . . . .. «© «© e «+ 2 
Tue GEOLOGY oF THE DIAMOND FigLps OF SOUTH AFRICA . « . 2 
QuarRTERLY WEATHER Report. By Professor BALFouR STEWART, 
HERES: | ee cee Pagecee: omit mane oo ae whe Je he ne SS 
Bret-Roor'SuGaR:. » 0 @ (ee) s Se & sels = 0h) = een 
LETTERS TO THE EDITOR:— | 
Dr. Balfour Stewart’s Opening Lecture at Owens College, Man- 
chester. — Lieut.-Col. STRANGE, F-R.'S. . . . . 2 - see se 5 
The Aurora Borealis.—A. S. Herscue.; W. G. Grass; T. G. 
Etcer; H. R. Proctor; Rev. R. Main; J. J. Hatt; C. 
PockitnGTon ; A. M. SmitH elie = Ge oh ene ito eran 
The Aurora Sept. 24.—G M. Dawson .... .- ee 
Hereditary Deformities.—W. Fietp POM eo 7 
The Cefn Reptile and the 7i#es.—W. Boyp Dawkins, F.R.S. . 7 
MAN AND NATuRAL SELECTION. By A. R. WatLtacE. . .... 8 
Tue Naturat History or Man. By H. Power, M.B. (With [élus- 
EFQTIDNS.) 9 3.4 couse neetectaee msloes. es) aie cl aaa uate Py a) 
IND GES cnsigcors - creel dou ames niet tec." (eo mngee «0 ga SRE 
A UNIVERSITY FOR' TEXAS Sr sc 6 ow he) 0 eo 
EartH CURRENTS. By W. H. PReEcE. ©. © .). “fi eeieeeeennEs 
Dr. C. W. Giimpet on DeEp-SEA Mup. . . - «5s «© « © © « » 16 
THE BRITISH ASSOCIATION :—SECTIONAL PROCEEDINGS. . + + I7—20 
ScreNTIFIC SERIALS .. . \. fe 6 |+s vs) 5 Sete ceunnSD ttn Ne Eaten Aneta 
DIARY ori. oe) eo ce ie ceo, white OEMS eo rs 
Books RECEIVED 0)... 5 ee oa) fae Reg OUR ee eee 


Errata.—Vol. ii, page 399, second column, line 18 from bottom, for 
“‘Electrometer” read “‘ Anemometer.” Page 512, second column, line. 7 
from bottom, for “requirements” read “ acquirements. 
