118 SECTIONAL ADDRESSES. 
untouched. There can be little doubt that in the course of time a large 
amount of cheap energy will be available in India for use in industrial 
processes, and as the country possesses a large and prolific population 
readily trained to mechanical and industrial processes, along with ample 
supplies of raw material for many such processes, all the conditions 
would appear to be favourable for its entry into the rank of manu- 
facturing and industrial nations. 
Modern Tendencies in Water-Power Development.—The large 
amount of attention which has been concentrated on the various aspects 
of water-power development during the past ten years has been 
responsible for great modifications and improvements in the design, 
arrangement, and construction of the plant. 
Broadly speaking these have been in the direction of increasing the 
size, capacity, reliability, and efficiency of individual units; of im- 
proving the design of the turbine setting and of the head and tail works ; 
of increasing the rotative speed of low head turbines; of detailed 
modifications in the reaction type of turbine to enable it to operate 
under higher heads than have hitherto been considered feasible; and 
of increasing the voltage utilised in transmission. 
The capacity of individual units has been increased rapidly during 
recent years, and at the present time units having a maximum 
capacity of 55,000 horse-power under a head of 305 feet are 
being installed in the Queenston-Cheppewa project at Niagara, while 
units of 100,000 horse-power are projected for an extension of the 
same plant. 
These modern high-power turbines are usually of the vertical shaft, 
single runner type, with the weight of the shaft, runner, and generator 
carried from a single thrust bearing of the Michell type. This type 
lends itself to a simple and efficient form of setting, while the friction 
losses in the turbine are extremely low. As a result of careful overall 
design it has been found possible to build units of this type having 
an efficiency of approximately 93 per cent. 
One of the great drawbacks of the low head turbine in the past has 
been its relatively slow speed of rotation, which necessitated either a 
slow speed, and consequently costly generator, or expensive gearing. 
As a result of experiment it has, however, been possible so to modify 
the form of the runner as greatly to increase the speed of rotation under 
a given head without seriously reducing the efficiency. 
Investigations in this direction are still in progress and promise to 
give rise to important results. At the present time, however, turbines 
are in existence which are capable of working efficiently at speeds at 
least five times as great as would have been thought feasible ten 
years ago. 
The non-provision of a suitable pipe line has, until recent years, 
tended to retard the development of plants for very high heads. Under 
such heads the necessary wall thickness, even with a moderate pipe 
diameter, becomes too great to permit of the use of riveted joints. 
Recent developments in electric welding and oxy-acetylene welding 
have, however, rendered it possible to construct suitable welded pipes, 
and by their aid, and by the use of solid drawn steel pipes in extreme 
cases, it has been found possible to harness some yery high falls, The 
