438 SECTIONAL TRANSACTIONS.—G. 
over and enclosing the copper wire coils, which constituted the primary and secondary 
parts of the circuit. The coarse wire secondaries of these transformers operated the 
load at reduced potential, and as this work ante-dated any production of incandescent 
lamps, a special form of small vibrating arc lamp was used, as also separate coils of 
resistance wire rendered incandescent. This, as is evident, was a pioneer realisation 
of the essential features of the transformer system of to-day. This feeble beginning, 
however, was followed in a few years by a widely expanding application of the 
principles involved. 
The paper also relates the inception of, or invention of, the ‘ three-phase winding.’ 
The first dynamo, the armature of which bore such winding, was devised in 1878-9, 
and forms the subject of patent $223,557, dated January 13, 1880. The original 
machine is preserved at the U.S. National Museum in Washington, D.C. The 
description in the specification of a patent relating to this, the first dynamo of its 
type, at first included the provision of three collector rings, allowing the output to 
be A.C. when desired, thus agreeing in that particular with the preceding two-phase 
machine above referred to. The bearing of this construction on modern power 
practice is evidently fundamental. 
Interesting circumstances concerning the construction of this first ‘ three-coil’ 
machine are noted in the present paper. 
The peculiar arrangement for regulation in conjunction with these three-coil 
early dynamos in maintaining a constant current in a circuit of arc lamps is briefly 
described, and matters which may be of general interest even at this day are alluded 
to in this connection. 
The writer closes his narrative by correcting a widely spread misconception as 
to the function of the unique air-blast commutator mechanism used in the machines 
of the old Thomson-Houston type. This function was always to secure steadiness 
in the lamps, as will be seen, and not, as often stated, merely a ‘ bold expedient > to 
blow out the sparks at the commutator. 
Tuesday, September 29. 
Sir Davip Mitnz-Watson.—The New Gas Industry. 
The gas industry commenced in London as a public utility in 1812, and was thus | 
in being when the British Association was formed. 
The centenary of the Association coincides with the Faraday celebrations, and 
some account of the great scientist’s interest in and work for the gas industry over a 
period of nearly fifty years is given. The commencement and development of the 
industry are sketched with a view to showing the difficulties of the pioneers, the 
progress made and the gradual development and extension of parliamentary control. 
The effects upon the industry resulting from the change in the requirements of 
gas consumers for heat instead of light are considered. The output of an average 
gas undertaking can be allocated in varying percentages between (a) domestic heating, 
cooking and hot water supply ; (b) industrial heating ; (c) lighting, and (d) power. 
Other statistics of the industry are given, and the gas industry is shown to be treating 
over 18 million tons of coal annually, whilst some 300,000 million cubic feet of gas are 
sold. The gas consumption per consumer in Great Britain averages 153 therms, 
or 30,547 cubic feet per consumer, equal to 30 therms per head of population. Com- 
parison is made with the sale of electricity, and it is shown that on a heat basis five 
times as much gas is sold as electricity, and that in the domestic field the proportion 
is as 18 to 1. 
The development of the gas-manufacturing process has been aided by various 
research organisations; the various carbonising processes are considered. The thermal 
efficiency of the modern continuous vertical retort is shown to be 86 per cent. 
Cheap power is now produced in gasworks from the heat previously wasted in 
chimney gases. New extensions have been made to the purifying processes, notably — 
the elimination of naphthalene, moisture and the extraction of benzole by activated 
carbon. 
The requirements to be satisfied by fuels to-day are severe, and a high standard — 
of precision of performance is expected. The development of gas-using appliances 
to give such precision in the home and in industry is explained. 
