G.—ENGINEERING 157 
sixpence for end charges and waggons, or 8s. 10d. for 100 miles. Allowing 
1-3 lb. per unit the cost is 0-061 pence, which is three times the cost of 
electrical transmission at a load factor of 0-4, so the coal waggon cannot 
compete with the grid. For shorter distances the proportion is slightly 
different, but always much larger. Carriage by sea is cheaper for long 
distances, if both pits and generating stations are conveniently situated. 
From Newcastle or Fife to London, for favourably placed pits, the 
cost is at present about 4s. per ton, so that electrical transmission from 
the nearest existing pits to London, 120 miles, will cost very nearly as 
much as carriage by sea to stations on the Thames banks, and only the 
cheapness of waste coal will give an advantage. Shipping freight charges 
are low at present, and a rise will make electric transmission economical 
to London, apart from the use of cheaper coal. Hence transmission 
from the pit-head stations may be safely undertaken, even if the amount 
of waste coal available should not suffice for the whole load, and if the 
Lincolnshire coal materialises, there will be plenty, some of it at a shorter 
distance. 
RATES AND TAXES. 
In the foregoing calculations of costs, the item of local rates has been 
omitted, for rates vary in different districts, and a general figure is not 
possible. The present charge for rates on electric supply stations is very 
high, and they have not come under the recent reduction of rates on 
machinery. Roughly, the item of rates on the generating plant alone 
amounts to about 0-06 pence per unit, considerably more than wages and 
salaries, and more than half the cost of coal. It is a tax or contribution 
towards local expenditure, which has grown to dimensions far greater 
than the early years of its operation seemed to indicate. While generating 
costs have gone down, taxes have gone up, and this charge is not generally 
realised, except by the engineer who is trying to reduce costs, but it 
amounts to nearly {100,000 per annum for a 100,000 kw. station. Now 
and again a few thousand pounds of credit balance in the year’s working 
of a station belonging to a town council is handed over ‘ for the relief of 
the rates,’ and often there is much protest that this is obtained at the expense 
of the consumer. The far larger sum quietly extracted as rates is not 
called in question. While the theory and practice of rating, as applied 
to factories and public utility companies and services, cannot be discussed 
here, it may be permissible to claim that the position of electricity and gas 
supply and railways has become anomalous. The supply mains are also 
assessed for rates, so that the total rate charge to the consumer is often as 
much aso «1 pence, while the selling price for domestic heating is 0-5 pence 
orlittlemore. Without demanding the complete abolition of rates on these 
public industries, we may reasonably claim some substantial reduction, 
such as one-half, amounting in our case to 0-05 pence per unit. If to 
this is added the equal sum which the cheap fuel of the pit-head station 
can achieve, a total reduction of 0-1 pence is obtained. ‘The importance 
of this will now be discussed. 
FuTURE CONSUMPTION. 
The cost given in Fig. 1 for generation in large steam stations is 0-25 
pence per unit at the usual load factor of o-4, while the selling price is at 
