1874.] _ Engineering. 543 
to the best advantage. The leathers, it is found, last a very long time, and if 
a valve has to be examined, or fresh leathers put in, it can be done in a few 
minutes, whereas the repair of metal-faced valves is both tedious and expensive. 
In the ordinary form of wagon drop a frame-work, usually of cast-iron 
columns, braced well together, supports an entablature, on the top of which is 
mounted a strong shaft with two large sheaves keyed thereon, to one or both 
of which is applied a powerful brake, worked by a lever from the upper rail 
level. The cage moves up and down in guides fixed to the frame-work, and 
is suspended by chains or wire ropes descending from one side of the sheaves, 
whilst from the opposite side hang heavy counterweights, which are suffi- 
ciently in excess of the weight of the cage to draw it to the top when the 
wagon is not on. Instead of weights Mr. Wrightson proposes to use water 
as the controlling agent in the drop. It would occupy too much space to 
enter into a description of how this is arranged, but it will be readily under- 
stood by anyone acquainted with the general principles of hydraulic machinery. 
Mr. F. J. Bramwell, as President of the Institution of Mechanical Engineers, 
recently delivered a very remarkable address on the performances of his 
profession and the progress made in mechanical science, from which it would 
seem that the mechanical engineer is necessary to our very existence, and 
that few modern improvements could have been adopted without his aid, and 
yet he urged that there was no reasun for supposing that the time had arrived 
when there need be any slackening in the development of engineering science, 
for there remain vast fields of research in which the ground has as yet scarcely 
been broken, while there are others practically untouched, and, even in those 
departments of engineering in which most progress has been made, far more 
remains to be done than has yet been accomplished. The waste of fuel was 
dwelt upon, and Mr. Bramwell remarked that for years past there have been 
constructed steam-engines capable of developing all the power at present 
obtained by the use of such engines, with the consumption of but little, if any, 
more than one-third of the fuel actually expended for that purpose, while in 
our metallurgical and manufacturing processes parallel instances exist. 
Attention was also directed to the transmission of power over long distances, 
for which purposes the chief methods adopted are by a fast running rope, by 
the exhaustion or compression of air, or by the flow of water through pipes 
under pressure. Amongst other subjects dwelt on’ were the substitution of 
mechanical for human labour; the mode of joining materials, and the - 
abvisability of devising some mode less crude than the present practice of 
employing bolts and rivets; on the utilisation of so-called “* waste” produéts ; 
on the advantages which the present generation of engineers may be expected 
to derive from the spread of technical education, and on the disadvantages 
which, on the other hand, are attendant on the modern tendency towards 
subdivision in engineering manufactures. 
The first paper read was one by Mr. John McConnochie, of Cardiff, “On 
the Bute Docks and the Mechanical Arrangements for Shipping Coal.” The 
dock accommodation at present existing affords a water area of 77 acres, to 
which will be added a further area of 54 acres when the new Roath Dock is 
completed. As the tidal water at Cardiff carries a deal of silt in 
suspension, and is therefore not suited for supplying the docks, they are fed 
with water drawn from the river Taff about 2 milesabovethem. Inconnection 
with the harbour accommodation there are at present four graving docks. 
The lock gates, as well as a large swing bridge over a junction lock, and the 
various hoists, tips, &c., connected with the new basin, are all actuated by 
hydraulic machinery supplied by Sir W. G. Armstrong and Co. As the pre- 
ponderance of the trade of the port consists of exports, vessels arrive in ballast, 
and there are seven steam cranes specially employed in the discharge of this 
ballast, four of which are capable of discharging 200tonseach perhour. These 
steam cranes discharge into railway wagons, by which the ballast is con- 
veyed a distance of about 2 miles to spare land, where it is deposited. The 
mechanical arrangements for shipping coals at the West and East Docks are 
on the high level, or balanced principle, but at the New Basin the low level 
system has been adopted into hydraulic tips for elevating and lifting the 
