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JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



yet been proved in so definite a manner. Frcm the results obtained it 

 appears that chloroform ought to be employed in much smaller quantities 

 than ether — a third or four part, for instance— fcr I understand that Mons. 

 Leblanc, by employing about twenty grammes of chloroform for a 

 hundred litres of air, did not obtain any particular results with Lilacs, and 

 that Mons. Aymard, by using the same quantity of chloroform as of ether, 

 nearly lost all his Lilacs, although the Lilies of the Valley, treated in the 

 same way, were a wonderful success. One can perfectly understand that 

 the buds of Lilies of the Valley, like the bulbs of Hyacinths, Tulips, &c, 

 being enveloped in a great thickness of tissues, require a larger quantity of 

 the vapour of ether or chlofororm to penetrate to them than the buds 

 of Lilac or Azalea, which are protected by quite thin scales. 



It may also be asked, to what is the influence of ether and chloroform 

 on plants to be attributed ? These two substances are anaesthetics, that is 

 to say, their vapour produces insensibility in animals, and in time 

 suppresses all movements indirectly caused by sensation ; it produces a 

 sleepiness, a numbness, an intoxication ; and, according to Professor 

 Johannsen, such is also its action on plants : it renders their vital power 

 latent ; it makes their repose and their sleep far deeper ; and to exactly the 

 same extent that these lose in duration do they gain in intensity, and 

 the more easy and rapid is their recovery. But can it be said that the 

 plant has been amestheticised ? When a Sensitive Plant is treated in 

 this manner everything happens in the same way as when an animal is 

 anaestheticised ; the mobility of the plant is for the moment destroyed ; but 

 who would venture to assert that sensibility, that is to say, sensation, 

 exists in the Mimosa, and that it has been abolished ? This is a hair- 

 splitting of words ycu will say ; but nevertheless there may be some 

 common sense in it. Dr. Raphael Dubois, who also studied the action ( f 

 anaesthetics on plants, wrote : " These anaesthetic vapours will produce 

 very marked modification of the tissues exactly corresponding to these 

 caused by the action of frost. ... It is a general law that not only do almost 

 all anaesthetics hinder the absorption of water by the cellular tissues, but 

 also that they tend to deprive them of part of the water which they 

 already contain. If you put any fleshy plants, such as Echeveria, into a 

 closed vessel in contact with the vapour of ether they will, after a certain 

 time, exude large drops of water through the epidermis. ... It is curious 

 to find that the most noticeable action of anaesthetics is generally closely 

 allied to that of cold, which also hinders the absorption of water and pro- 

 duces in frozen earth its separation &c. But cold, as is well known, is an 

 anaesthetic." * 



We kin.w that a spell of cold or of very dry weather greatly assists the 

 Kiibsequent forcing of plants that have been subjected to their action. 

 May we not attribute the influence of ether and chloroform to their dry- 

 ing powers, drying up and coagulating the protoplasm and the food reserve 

 contained m the stems, and still more at the base of the buds, in the same 

 way as cold or -reat drought dees ? Or just as Alpine plants which have 

 boon for a long time benumbed under the snow speedily recover and begin 

 to flower as soon as a ray of sunlight arrives to melt it, so flowering 

 branches, coagulated, dried up, and rendered torpid by ether or chloro- 

 * Dr. Raphael Dubois, quoted in Lc Jardin, 1002, p. 12. 



