TRANSACTIONS OF SECTION G. 507 
the following laboratories on the ground floor: a top-lighted laboratory, a rail- 
way laboratory, a hydraulic laboratory, and also a boiler-room. 
The top-lighted laboratory consists of four bays, having a total floor area - 
of 17,628 square feet. The floor is of timber decking, supported on steel 
girders and brick columns. Underneath is a basement of equal area, in which 
all mains, pipes, cables, countershafts, &c., are placed. Machinery can there- 
fore be installed without any structural alterations being made necessary. 
Steam is supplied from the boiler-room adjoining. A five-ton travelling crane 
is fitted to each bay of the laboratory. 
The railway laboratory has a floor-area of 3,200 square feet. A portion of 
the laboratory has been designed as a wind-flume capable of producing a current 
of air of sixty miles per hour, the object being to ascertain the effect of wind- 
pressure on train-models, aeroplane-wings, and structures. 
The hydraulic laboratory has a total floor-area of about 8,000 square feet. 
The equipment of the laboratory consists chiefly of supply tanks, measuring 
apparatus (including a standardising tank of 12,500 gallons capacity), weir- 
boxes, a west sump and an east sump (the latter having a capacity of 22,000 
gallons) connected by flumes, a complete turbine plant, and two Gwynne pumps, 
as well as a twelve-inch Venturi meter, and mains and piping. The chief 
feature of the design of the laboratory is that the power to be supplied for the 
circulation of the water through the equipment has only to overcome the 
frictional resistance of a vertical lift, and is therefore at a minimum; the whole 
circulation can be controlled by one man standing at the pumps; and experi- 
ments with the different apparatus can take place independently and simul- 
taneously. 
The boiler-room contains two Lancashire boilers and one water-tube boiler, 
each capable of giving 5,000 lbs. of steam per hour, arranged so that they can be 
available for experimental purposes. Underneath the roadway behind the 
boiler-room are the coal-bunkers, capable of holding a hundred tons of coal, as 
well as an ash-pit from which the ashes can be hoisted through a trap-door and 
emptied directly into the carts. 
The paper concluded with some particulars of the advanced courses in the 
Imperial College, showing that the objects of its founders have already been 
successfully carried out. The College is still rapidly developing, and will 
soon provide every facility for post-graduate study and research for students 
from all the colleges of Greater Britain. 
TUESDAY, AUGUST 25. 
The Section divided into two Sub-Sections, G I. and G II. 
In Sub-Section G I. the following Papers were read :— 
1. The Metropolitan Electric Railways proposed for Sydney. 
By J.J. C. Braprisip, M.Inst.C.H. 
The paper described the proposed scheme for which Parliamentary sanction 
is being sought. It comprises the construction of an underground railway in 
the City itself, and the electrification of some of the suburban railways to 
connect up with the underground railway. Statistics show that the present 
railway and tramway systems are, or will shortly be, incapable of handling the 
rapidly increasing traffic. It is proposed to connect North Sydney and the 
City by means of a bridge across the harbour, while another bridge would 
connect the City with the western suburb of Balmain. It was maintained that 
a bridge would be cheaper than a subway, and would give better gradients and 
greater comfort. Since Sydney is the fifth port in the Empire, it is essential 
that the fairway be not impeded. For this reason the proposed harbour bridge 
crosses in a single span of 1,600 feet, with a headway of 170 feet above high- 
water. It provides for four lines of railway, beside vehicular and passenger 
traffic. The design and material are discussed, and a nickel-steel cantilever 
bridge is recommended, at an estimated cost of 2,600,000/. Details were given 
