TRANSACTIONS OF T1IE SECTIONS. 
157 
Oa mne Experiments upon a Telegraph for communicating curw Fiver, 
and Seas, without the employment of a submerged Cable. 
By l B. Lindsay. ( Communicated by Rich. B. Grantham, 
Mr. Lindsay's proposition or invention consists in communicating intelligence 
L-'oagh rivers and seas without the U3e of a submerged cable. t u e 
^ experiment was tried on a small scale in the middle of last me.nth across the 
n *--'kin at Portsmouth, in the presence of Capt. Beattie, Ro)»I L g * 
'd.-T engineering officers : the distance w«9 530 feet. 1 lie next an tance 
i> r tu were made across the entrance to the harbour at 1 ortsmout 1 , 
kingfiOO yards and the other 1380 yards. . , . • i t,. 
He placed along upon each shore a copper wire, to both ends d whteh he 
''wW a sheet of copper, one pair of these sheets being opposite to , lc 0t ^ r P^ 
‘, r .G the shore. All the other four sheets were immersed m the water, but ’they 
not isolated. Upon one line of wire the battery was placed, and upon iue 
r.Wi the telegraph; and upon the battery being brought into action, the neei <-» 
K *n motion on the opposite shore. , . , 
Mr. Lindsay considers that the distance between the copper plates on each shore 
*<J be equal to the sum of the two widths across the river or sea at the plates , 
7 ,l .v increasing Uie strength of the battery, or enlarging the area of tnc coppe 
' i: «, the plates can be brought nearer to each other. 
I" Ihe last experiments the distance across two of the plates was 811,1 J to 
‘rb, and the other distance 1380 yards. Oiie of the plates was laid at Blockhouse 
•rt, and the nthor nf iVir. »u,a.l tnnmi. of RnlUrnnrt. 
r i- 'iv-wiy, uiui mu 
me of comnnmicatiou. 
., f R’ is, besides the conw 
- 'V l,c ‘ s ' aes tIlu copper of the ships, the iron chains by which the floating 
!i,;.^'V! rawn across the Harbour ; and still, with all these incitements to draw oft 
"”db tnC flu ' lc1 ' there was »o interruption of the current in its course to the 
these experiments, Mr. Un.lsav believes tot there U 
"H«oriL^ y '“Clothe employment of this kind of telegraph; and it he had the 
l.' L ' lty - be would not fear to extend it across much wider spaces than haxe 
Thr^ bec " attempted. 
* I "llWdfP e ! l . ments ^at intelligence can be transmitted across rivers and seas, 
1 ' a i) In Jo 18 k ," ld of t^’legrapdi may bo used for communicating across rivers in popu- 
lf iiuon n 3, r hefL ‘ ,here may be large numbers of vessels passing und repassing ; but 
ir.PM . j., 1 ? ' ar gev scale, ueross seas from one kingdom to another, a vast miprove- 
1. ■!.!,. tu ' 1C ttttaiucil as compared with the present system by submerged cables, 
nau l' accidents, and probubly undergoing a vast amount oi depreciation. 
ft; !:’ M<Derm °tt explained a new railway brake, which is brought into action 
c pressure of the steam in the boiler. ’ 
0/i a Method of Boring Holes in Rock for Tunneling Purposes 
j n{ ^ Hy J. Nasmyth, P.lt.S. 
With tea mot ^°d of boring holes for blasting, by striking t 
pucd the « V ?" “ a,nmers , a great portion of the edict is lost by w 
!? ^nvei-t thp*w ia ” * >ur ‘ overcome this defect, Mr. N . . . 
Jv “'S-box riv* 10 a piston-rod, to work in an air-tight cylinder through a 
Pressure of A mt ‘ans, when the piston in drawn to the end of the cylinder. 
Hie atmosphere will force it back again with accumulating velocity, 
at the cud of the 
hat is commonly 
