PROPAGATING DEVICES. 49 



propagating-oven, is illustrated in Fig. 53. It is an interest- 

 ing apparatus, and is worth attention as showing the care 

 which has been taken to control the conditions of vegetation 

 and germination. It is too elaborate for common purposes, 

 and yet for the growing of certain rare or difficult subjects 

 it might find favor among those who like to experiment ; 

 and it affords an accurate means of studying plant growth 

 under control. The apparatus is sold in France for about 

 |6. All the portion below the glass top, P, P, is made of 

 earthenware. The base, a a, holds a lamp, d ; ^ is a. water 

 reservoir, to which water is supplied by means of the fun- 

 nel, j. A vase or rim, b b, rests upon the base, and upon it 

 a plate or disc, c c, is fitted. Above this is the glass top, P P. 

 Air is admitted to the apparatus at i, K K, and between 

 the vase and plate, as at c on the right. The plate con- 

 tains two concentric circular grooves, g g and h h. In 

 these grooves the soil is placed or pots plunged. The heat 

 circulates in the valleys tn and nnnn, and supplies a uni- 

 form temperature to both sides of the plants. 



Barnard's propagating-tank. Fig. 54, is a practicable de- 

 vice for attachment to a common stove. A similar appa- 

 ratus may be attached to the pipes of a greenhouse. The 

 tank consists of a long wooden box made of matched 

 boards, and put together with paint between the joints to 

 make it water-tight. The box should be about 3 feet wide 

 and 10 inches deep, and may be from 10 to 30 feet long, ac- 

 cording to the space required. In the middle of the box is 

 a partition, extending nearly the whole length, and on the 

 ■ inside, on each side, is a ledge or piece of moulding to 

 support slate slabs to be laid over the entire surface of the 

 box. The slates are supported by the ledges and by the 

 central partition, and should be fastened down with cement 

 to prevent the propagating-sand from falling into the tank. 

 One slate is left out near the end, next the fire, to enable the 

 operator to see the water and to keep it at the right level. 

 On the slates sand is spread, in which the cuttings may be 

 struck, the sand nearly filling the box. At one end of the 



