266 



Propagating-House heated by hot Water 



Fig. 66. Dahlia and Hollyhock Garden, 



whole garden from be- 

 ing seen at once when 

 entering. There may 

 also be a few plants of 

 fupressinae, or other 

 evergreens, sprinkled 

 down the middle of the 

 garden, from b to b, in 

 order to form a back- 

 ground to the dahlias 

 and hollyhocks ; for this 

 garden, like fig. 64., is 

 one of those the beau- 

 ties of which are to be 

 seen in succession, and 

 not at a single glance, 

 as in the design fig. 63. 

 The dahlia beds are so 

 disposed as that every 

 variety may be seen from 

 the walk. The width of 

 the beds is 3 ft., which 

 will admit of two rows, 

 the plants of one row 

 alternating with those 

 in the other. In order 

 to preserve the exact 

 form of the beds, they 

 ought to have concealed 

 brick edgings, formed in 

 the manner shown in 

 figs. 56,37. in p. 217., 

 or by triangular bricks 

 made on purpose. The 

 shapes may also be pre- 

 served by iron I'ods 

 raised 6 in. above the 

 beds, and securely fixed. 



Art. IX. Description of a Propagating-House heated by hot Water 

 circulated in Brick Troughs. By J. M. Lindsay. 



According to my promise, I forward for your inspection a plan and section 

 {fig- 67.) of a propagating-house in the Hammersmith Nursery, recently 

 heated (by my employers, Messrs. John and Charles Lee) by hot water cir- 

 culating in brick troughs lined with cement; top and bottom heat being 

 produced by the same means. We have now had the plan in operation a suf- 

 ficient time to test its merits, and I feel quite justified in asserting that it far 

 surpasses every other means with which I am acquainted for the purpose of 

 commanding a regular, steady, genial, and moist bottom and top heat ; so much 

 so, that I have not the least doubt that, when its superior advantages are fully 

 known, it will ultimately supersede the use of all the fermenting materials 

 which are generally used as a medium for bottom heat, and also the use of 

 iron pipes for horticultural purposes. 



The house to which the system has been applied here is fifty feet long and 



