EXAMINATION OF ALL THE EVIDENCE REGARDING SAFETY-LAMPS 181 
the business expected to be carried on with 
her, and also on the capital people may feel 
disposed to risk in the speculation. 
n. The roof to have an opening in it, 
through which masts could be elevated, and 
rigged schooner or lugger fashion. The 
butts of the , masts to be each fixed in a 
moveable centre, firmly secured in the 
middle frame. Such would be the breadth 
of the deck, that the sheets would be quite 
sufficient to spread the sails ; no “ booms” 
would be necessary. Bowsprits could be 
easily run out ; and the rest of the rigging, 
such as stays, run down through the roof, 
through proper openings, and all got to 
rights in little time. The lower leech of 
the sail, when hauled flat, would rest upon 
the roof, which would thus become a part 
and parcel of the sail. 
Your nautical readers will readily under- 
stand these suggestions. In my next I 
will continue the subject, with your permis- 
sion. 
I send you here with the drawing of 
the Huntsman steamer, which was by some 
neglect omitted in my former packet. 1 1 
are the chimneys ; 2, steam eduction-pipe ; 
3 3, cabin chimneys ; 4, cooking-stove 
chimney ; 5, steering- station ; 6, ladies’ 
cabin ; 7, gentleman’s cabin ; 8, cook’s 
house ; 9, boilers ; 10, fire-wood ; 11, 
flag-staff used for steering by ; 12, pipe 
from safety-valve. 
Your well-wisher, 
E. Talebois. 
Liverpool, Oct. 7, Mech. Mag. 1835. 
VENTILATION OF TUNNELS. 
Sir, — I think the following plan for ven- 
tilating tunnels would be an improvement 
upon that which I have seen generally 
recommended. If the tunnel is one-fourth 
of a mile long, let a circular orifice be made, 
12 inches in diameter, from the centre of 
the top to the surface ; snd if half a mile 
or more long, connect 2 other similar orifi- 
ces in the manner represented in the follow- 
ing diagram, about 200 yards on each 
side of the centre passage. 
These auxiliary orifices rising about fiVe or 
six feet before passing to the principal, at 
not more than one -third of the width from 
the sides. Under each passage there 
should be placed a strong gas-light lamp ; 
so that all three lamps would be seen at 
either end. The main passage should, at 
two feet from the surface, pass through a 
fire in a close iron stove, with a continua- 
tion or funnel of three or four feet, con- 
tracted at the top to about four inches diame- 
ter. In this way an excellent ventilation would 
be produced at all seasons, from the strong 
current always rushing up to the rarified 
part, 
I am. Sir, 
Your obedient servant, 
G. L. Smart. 
Enfield, Dec. 4, l835. — Ibid. 
REPORT FROM THE SELECT COM- 
MITTEE OF THE HOUSE OF COxM- 
MONS ON ACCIDENTS IN MINES: 
-SIR H. DAVY'S AND OTHER 
SAFETY-LAMPS. 
The report from the Select Committee ap- 
pointed by the House of Commons on the 2nd 
of June last, to investigate the subject of ac- 
cidents in mines, which, together with the evi- 
dence given before the committee, was order- 
ed to be printed on the 4th of the ensuing Sep- 
tember, has lately appeared, and persents a 
body of facts and inductions from them of the 
moi^t interesting and momentous character. 
We purpose to extract and transfer to the 
pages of the Repertory whatever relates to the 
subject of Safety-lamps, and afterwards to 
enter into a critical examination of all the, 
evidence respecting it, and of the conclusions 
of the committee regarding it ; that portion of 
the entire subject which received the commit- 
tee’s attention being as important in a scienti- 
fic as itis in an economical point of view; 
and the meanshaving at length been furnished, 
we conceive, of arriving at some satisfactory 
determination relative not only to the inven- 
tion and progressive improvement of the safety- 
lamp, but also to the degree of actual safety 
to be obtained from its use, and the influence 
of its employment in the extension and con- 
duct of mining for coal, We begin with the 
committee’s report, retaining the marginal re- 
ferences to the illustrative points of evidence, 
many of which also we shall give in the 
sequel. 
