CHAPTER VI 



FORCING BY ELECTRIC LIGHT 



IF the use of electric light under glass would make up for a defic- 

 iency of sunshine the market gardener would have an invaluable 

 agent in the rearing of winter stuff and numerous experiments 

 point to the possibility of this being the case. 



With a view to finding out if electric light had a similar effect 

 on plant growth as solar radiation, Sir William Siemens, an elec- 

 trical engineer of great fame, commenced in the winter of 1880- 

 1881 some very interesting experiments at his home in Tunbridge 

 Wells, Kent, which were only terminated by his untimely death 

 due to an accident. 



He installed in a greenhouse of 2,318 cubic feet capacity a 

 powerful electric arc lamp ; in this Jiouse were planted peas, 

 French beans, wheat, barley, oats, cauliflowers, as well as straw- 

 berries, raspberries, peaches, vines and tomatoes. During the 

 whole of the experiment a temperature of 60 Fahrenheit was main- 

 tained. The effect of the lamp was found at the commencement 

 of the experiment to be anything but satisfactory. On the pre- 

 sumption that the naked light from the arc was too strong, he 

 devised a means of softening the rays by introducing a jet of 

 steam through small tubes which produced a cloudy effect be- 

 tween the plants and the light. This had a decidedly beneficial 

 effect, but still the plants did not respond in the way that had 

 been anticipated. He next arranged a clear glass lantern round 

 the light to act as a screen after which satisfactory results soon 

 manifested themselves as the following testifies : 



PEAS. 



Raspberry Canes 

 Strawberries 



Vines 



SOWN END OF OCT. 



Planted Dec. i6th 



Planted middle of 

 Dec. 



Broke Dec. 26th 



READY FOR PICK- 

 ING FEB. 16. 



Fruit ripe on March 



ist 



Produced ripe fruit 

 of excellent quality 

 and flavour on Feb. 



I4th. 



Grapes of unusually 

 fine flavour picked 

 off them on March 



i6th. 



On a former occasion Siemens made an interesting experiment 

 on strawberry plants. Having proved to his own satisfaction 



