180 REPORT—1857. 
On the Working and Ventilation of Coal Mines. 
By Joun BRAKENRIDGE. 
It was recommended, that instead of commencing to get coal when the straight- 
works and board-gates were only partially completed, coal-owners should drive the 
board-gates to a cross heading at, or nearly at, the extent to which it might be pro- 
posed to work and draw the coal by the same engines and pits, and that the upcast 
pit should be sunk, and the furnaces for creating a draft placed at the highest point 
in the bed of coal. Then that from this cross heading the coal should be got in the 
opposite direction, i. e. toward the downcast pit, instead of from it as at present, 
and thus the danger would be greatly abated. 
By such mode of working, the ventilation would be more natural; a considerable 
portion of the gases would be liberated and discharged from the coal before the wide 
works in the banks were begun, and the current of the gases as they exude from 
the coal or the roof would be upwards from the men and towards the upeast pit, by 
which they would make their escape; the whole mine would then be less liable to be- 
come inflammable and explode. 
All the precautions practised in the present mode of working would be necessary 
in this, but in a less degree, and the safety of the mine would depend less upon 
them; and should an explosion unfortunately happen, it would be behind the men, 
and the force of it would be towards the upcast pit, giving the men the almost cer- 
tainty of escape towards the drawing pit, through the passages in the solid coal. The 
sacrifice of human lives, as well as much of the damage to the mine, would therefore 
be in a great measure averted. 
A Plan for Diminishing the Strain on the Atlantie Cable by an Elastic 
Regulator. By C. Brooxe, M.A. F.R.S. 
The proposed plan consists in suspending a block with one sheave of the same size 
as the paying wheels by a bundle of parallel cords of vulcanized india-rubber from a 
boom rigged to the mast. ‘This elastic bundle should be of sufficient length and 
thickness to elongate 10 or 12 feet, by an increase of strain from perhaps four to six 
tons; and should be placed vertically over one of the pairs of paying wheels, and the 
cable move through it between the wheels. As the cable is double, the bundle will 
be required to bear twice the strain of the cable. By this arrangement, from 20 to 
24 feet of cable would be given out by an increase of tension of from two to three 
tons, and taken up again as soon as the tension is diminished. 
On Improvements in Iron and Steel, and their Application to Railway and 
other purposes. By J. W. Dovps. 
On Macadamized Roads. By G. H. Fritu, C.B., County Surveyor. 
The author presented a compendious review of road-making, especially in Ireland. 
He points out evils in the prevalent systems of road-making ; treats of the proper 
magnitude of the stones required for mending, the influence of weather on the pro- 
cess, the obstacles of various kinds to good road-making, and gives a specification for 
keeping in repair a certain portion of road near Dublin, by which a large annual 
saving was effected. Reference is made to continental as well as English authorities. 
On the Effect of the Resistance of Water to an Extended Cable. 
By A. 8. Hart. 
On Controlling the Movements of ordinary Clocks by Galvanie Currents. 
By Joun Harrnopr, F.RA.S. 
Since the application of electricity to the purposes of the telegraph, various methods — 
have been had recourse to for working clocks at distant stations by a normal clock at 
an observatory ; or by causing one clock in a large establishment to work several 
sympathetic clocks in different parts of the building, The advantage of being able 
to make several clocks show the same time as a normal clock regulated by astrono= 
a sc 
ae 
ee ee ee ee 
