236 THE SCIENTIFIC PAPERS OF 



5. That the radiation of heat from powerful electric arcs can be 

 made available to counteract the effect of night frost. 



6. That while i under the influence of electric light, plants can 

 sustain increased stove heat without collapsing, a circumstance 

 favourable to forcing by electric light. 



7. That the light is efficacious in hastening the development 

 of flowers and of fruit ; the flowers produced by its aid are 

 remarkable for intense colouring, and the fruit both for bloom 

 and aroma, without apparent augmentation of the saccharine 

 constituents. 



8. That the expense of electro-horticulture depends mainly upon 

 the cost of mechanical energy, and is very moderate when natural 

 sources of such energy, as waterfalls, can be made available. 



Some observations made by Dr. Schiibeler, of Christiania, to 

 which my attention has been drawn, fully confirm the conclusion 

 indicated by my experiments with electric light. According to 

 Dr. Schiibeler, plants are able to grow continuously ; and when 

 under the influence of continuous light, they develop more 

 brilliant flowers and larger and more aromatic fruit than when 

 under the alternating influence of light and darkness. 



The useful influence of the electric light in horticulture having 

 been thus established, I have taken steps to test the principle upon 

 a working scale. Natural sources, such as water power, not being 

 available, I have had to resort to steam as the motive agent. 

 With this object I have laid down a 6 horse-power horizontal 

 engine, by Tangye Brothers, and a Cornish boiler, fitted with 

 2 Galloway tubes in the flue, close to the conservatories at Sher- 

 wood, and at a distance of somewhat less than a quarter-of-a-mile 

 from the farm buildings. The power of this engine is sufficient to 

 give motion to two dynamo machines, capable of producing 12,000 

 candle-power of light. The steam, after doing its work in the 

 engine, will be made available as a heating agent for the hot- 

 houses ; but it having been found undesirable to pass such steam 

 directly into the pipes leading to the houses, an intermediate 

 tubular heater is used to effect the condensation of the steam, and 

 to communicate its latent heat to the water circulating through 

 the ranges of pipes in the usual manner. The fires now necessary 

 to maintain the heat of the circulating pipes are suppressed, and 

 that below the steam boiler substituted, which, admitting of an 



