12 REPOBT— 1882. 



and horticulture for upwards of two years, I can speak with confidence 

 of its economy, and of the facility with which the work is accomplished 

 in charge of untrained persons. 



As regards the eflPect of the electric light upon vegetation there is 

 little to add to what was stated in my paper read before Section A 

 last year, and ordered to be printed with the Keport, except that in 

 experimenting upon wheat, barley, oats, and other cereals sown in the 

 open air, there was a marked difference between the growth of the plants 

 influenced and those uninfluenced by the electric light. This was not 

 very apparent till towards the end of February, when, with the first 

 appearance of mild weather, the plants under the influence of an electric 

 lamp of 4,000 candle power placed about 5 metres above the surface, 

 developed with extreme rapidity, so that by the end of May they stood 

 above 4 feet high, with the ears in full bloom, when those not under its 

 influence were under 2 feet in height, and showed no sign of the ear. 



In the electric railway first constructed by Dr. Werner Siemens, at 

 Berlin, in 1879, electric energy was transmitted to the moving carriage 

 or train of carriages, through the two rails upon which it moved, these 

 being sufficiently insulated from each other by being placed upon well 

 creosoted cross sleepers. At the Paris Electrical Exhibition the current 

 was conveyed through two separate conductors making sliding or 

 rolling contact with the carriage, wliereas in the electric railway now in 

 course of construction in the north of Ireland (which when completed 

 will have a length of twelve miles) a separate conductor will be pro- 

 vided by the side of the railway, and the return circuit completed 

 through the rails themselves, which in that case need not be insulated ; 

 secondary batteries will be used to store the surplus energy created in 

 running downhill, to be restored in ascending steep inclines, and for passing 

 roadways where the separate insulated conductor is not pi-acticable. 

 The electric railway possesses great advantages over horse or steam-power 

 for towns, in tunnels, and in all cases where natural sources of energy, 

 such as waterfalls, are available ; but it would not be reasonable to sup- 

 pose that it will in its present condition compete with steam propulsion 

 upon ordinary railways. The transmission of power by means of electric 

 conductors possesses the further advantage over other means of trans- 

 mission that, provided the resistance of the rails be not very great, the 

 power communicated to the locomotive reaches its maximum when the 

 motion is at its minimum — that is, in commencing to work, or when 

 encountering an exceptional resistance — 'whereas the utmost economy is 

 produced in the normal condition of working when the velocity of the 

 power-absorbing nearly equals that of tl^e current-producing machine. 



The deposition of metals from their solutions is perhaps the oldest of 

 all useful applications of the electric current, but it is only in very recent 

 times that the dynamo current has been practically applied to the refining 

 of copper and other metals, as now practised at Birmingham and else- 

 where, and upon an exceptionally large scale at Ocker, in Germany, 



