NOTES AND ABSTRACTS. 



133 



5 per cent, alcohol and 0.1 per cent, ether solution. It burst into 

 leaf twenty-six days earlier than the non-injected shoots. Carpinus 

 Betulus gave similar results. Populus canadensis and P. halsamifera 

 require a 10 per cent, alcohol solution. If the injections are to be of 

 any value they must be made before the dormant period is over. 



S. E. W. 



Forcing" Vegetables, &e., Thermosiphon for (Rev. Hort. 

 Beige, p. 93, March 15, 1911; p. 113, April 1, 1911; p. 155, May 5, 

 1911; p. 190, June 15, 1911; figs.). — A series of articles written with 

 the object of explaining the advantages of the thermosiphon, a simple 

 type of hot-water apparatus for heating frames. The use of manure for 

 this purpose has been proved to have many disadvantages, and the usual 

 form of brick pit heated by pipes is both cumbrous and costly. This 

 apparatus, which requires practically no mason work and is applicable 

 to the usual wooden frames, is described and illustrations of two types 

 suited to the use of market gardeners are given. In one type the pipes 

 are arranged so as to be laid on the top of the soil merely, among the 

 plants, until the temperature of the soil has reached the desired degree, 

 when the pipes are withdrawn and, if required, moved to other frames. 

 It is thus possible to heat a considerable number of frames with one 

 portable apparatus, as after the first few days it will only be necessary 

 to introduce the pipes every other day or even once in three days. 

 Heating from below the soil requires, of course, more elaborate laying 

 of the pipes, which in the case of perennial plants must be put in 

 position before the plants are moved into the frame in autumn. In 

 either case December 15 is given as the earliest date at which it is 

 advisable to begin forcing perennial vegetables. Careful directions as 

 to cultivation, degree of heat necessary, and general management are 

 given for raising asparagus, sea-kale, chicory, lettuces, &c., for the 

 early market. — M. L. H. 



Forcing-, Modern Methods of. By Curt. Reiter (Rev. Hort, 

 de VAlgdrie, p. 50, Feb. 1911). — This is an extract from the Journal 

 d' Horticulture Suisse, and concerns the forcing of various plants in 

 that climate so as to be ready by Christmas. The principal methods 

 employed are : — ■ 



1. Warm-water treatment for lily of the valley, lilac, azalea, and 

 most spring-flowering bulbs. 



2. Etherization for lilac and generally all flowering shrubs. 



3. The cultivation of all Dutch-grown flowering bulbs, and 

 especially of hyacinths, Narcissus in Southern France for a year before 

 forcing in the North. 



In forcing lily of the valley the crowns should be plunged about 

 November 27 in a basin of warm water at a temperature which is kept 

 as regularly as possible at 35^ Cent, for about fourteen or sixteen 

 hours. They should afterwards be placed in drills in a temperature 

 of 30° Cent. By December 15 the crowns may be removed to a 

 greenhouse where the temperature is 15° to 18^ Cent. After their 



