1.32 
REPORT — 1847. 
MECIIAXICS. 
On the Adrantages to he obtained by the adoption of the Eladic MalleahU 
Iron Tube, as a means of developing the principle of Atmospheric Proptd- 
sion on Eailways. By Messrs. Clarke and Varlev. 
erhe invention may be seen at work on an experimental lineofSOOfeetinleBjth, 
with a tube of 15 inches in diameter, near the Poplar Station of the Londooiiid 
Blackwall Railway.) 
On the Tvrbine. By J. Glynn, F.R.S. 
(Printed among the Reports, p. 14/•) 
ExperhnenU on the Strenytli of Iron Columns. 
By Professor E. Hodgkinson, F.R.S. 
On the Application of the Wave System of Mr. Scott Russell to ike Con- 
simction of Sailiny Vessels. By J. P. Phipps. 
On the Iron Lock-gates of Sevastopol. By G. Rennie, F.II.S' 
On an Apparatus for giving Light under Water in Dmng operalioM. 
By \V. S. Ward. 
The apparatu-s consists of a reservoir composed of several copper tubes (in 
pi^eiit apparatus seven) 1^ inch in diameter and 9 inches long, put together lih 
® s® M to give great strength incase the mixed gases with which dity 
filled should by accident explode. Six of the tubes are arranged round the ce^ 
one and soldi-red into a piece of brass drilled so as to connect them all; and in Au 
apparatus mixtures of oxygen and hydrogen and of oxygen and carburetted bydrofen 
were repeatedly exploded to prove its safety. Tlie apparatus is wry portahlr. uf 
**?-*^L heavier than to prevent its buoyancy in water, and is capable of gfhil 
five or six caudles for about a quarter of an hour. The mbed gsses, 
® I '' P**s*”K through u llemming's jet, issue through a small aperture so astoigm® 
a Iwul of lime, proilucing a small but very brilliant light, which is covered by aa in- 
xeried bell-glass placed in a shallow vessel of water, so that the products 
ouHtion ^ape under the edge of the inverted glass shade. In this form h miy “ 
with great facility in moderate depths of water, tlie chief requisite Mnglolni* 
it muckly before the glass shade becomes so hot as to be broken by the f*®* 
tact of cold wnler. The gases art* compressed into the reservoir bva fotct-puap: 
and common gas is preferred to be mixed with the oxygen ga£. the former 
1° n'*^**’ carbonic acid which results from the combustion may »«• 
tuaiiy kwp out the water from the glass shade. This pressure is ten atmospbet^ 
tie coal gas is more manageable than pure hydrogen, the most intense part of 
ame being further distant from the aperture of the jet, and having so little 
destroying the lime bait, that it does not require to be often turned ; and themiOT 
arc scarcely liable to explosion unless the aperture be of much greater «»• 
c cr thM IS requisite in this apparatus. It is submitted that this apparatus n»y 
useful to divers inspecting the holds of sunken ships and other dark pUfo » 
moderate depths under water. 
