is 



JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



It was proved from the experiments of Moris. Ledieu that — 



1. The varieties of Lilacs usually forced in Germany, ' Marie Legraye,* 

 ' Charles X.,' and 'Leon Simon,' were in full flower eighteen days after 

 being placed in the greenhouse. The variety ' Marie Legraye ' even 

 expanded its flowers still earlier. 



2. Different kinds of flowering shrubs were made to flower in a much 

 shorter time than by the ordinary methods now in use. Plants of the 

 same variety that had not been etherised did not flower at all, or flowered 

 very badly in the comparative trials in early forcing, or at any rate 

 opened their blossoms eight or ten days after those treated with ether. 



3. The plants treated with ether could be forced at a lower tempera- 

 ture than that required by those not thus treated. 



Hamburg is one of the largest centres for the forcing of Lilacs in 

 Germany. One of the principal forcers of that city, Mons. Friedrich 

 Harms, devoted himself to a series of experiments on the same subject the 

 results of which fully satisfied him. He described them in an article, 

 illustrated with some very instructive photographs, which appeared in 

 Motlcr's G&rtnerzcitung. The conclusions that he drew from these 

 experiments may be summed up as follows : — 



1. Lilacs treated with ether force much more rapidly than the others. 



2. In consequence of the ether treatment, some varieties of Lilacs 

 which are known to be difficult to force can be forced w T ith equal ease as 

 1 Charles X.,' ' Marie Legraye,' &c, which are known as good subjects for 

 forcing. 



3. Some Lilacs not having been specially prepared for forcing, that is 

 to say, plants taken up from the open ground with a ball of earth and 

 etherised, and then put in a warm house, developed their flowers perfectly 

 and very rapidly. * 



The experiments made in France were chiefly made to confirm and 

 prove the results obtained by the German gardeners, to try the action of 

 other amesthetics, and to draw from them theoretical and practical con- 

 clusions. Thus Mons. Charles Leblanc communicated to the Societe 

 centrale d'Horticulture de Nancy on April 13, 1902, the results of his 

 researches. In a general way his trials confirmed the very important 

 influence of ether vapour on forcing ; but what made them far more inter- 

 esting was that he turned his attention, not only to ether, but also to 

 chloroform. He says : — 



M My experiments were quite successful. On February 19 I chloro- 

 formed some plants of Azalea mollis, giving them a dose of half the quantity 

 I should have used had it been ether. I left the plants forty-eight hours 

 under the influence of the chloroform, and on February 21 I put them in a 

 greenhouse at 1N° ('. (Go F.) From March 5 the flowers began to 

 . \ | >,iii<l u little, and attained about to their full dimensions on the 8th, 

 whereas plants grown for comparison were not expanded until March 21. 

 Lilacs treated with the same amount of chloroform were a little retarded ; 

 as regards those not chloroformed, in my opinion, the amount given them 

 was too st rone;." + 



The trials made by Mons. Aymard, junior, a horticulturist at Mont- 



* Bulletin de i<i Sociiti centrale d'Horticulture de Nanei/, 1901, p. 201). 

 t Ibid. 1909, pp. 88 and 40. 



