448 



PITS AND FEAMES. 



them in the span-roofed form. A glance 

 at the ground-plan of this garden (vide 

 Plate V.,) will show the propriety of 

 this arrangement. 



Dalkeith succession pine-pits. — These pits 

 are exactly similar to the last, only that 

 they are 10 feet wide within, and about 

 10 feet deep at the back, and are filled 

 more than half-way up with leaves, into 

 which the plants are plunged. They are 

 sunk under ground like the former. The 

 walls are of 9 -inch brickwork, wrought 

 solid, and coped with wood on the back 

 walls, and with stone on the front, as 

 the latter, being more liable to be affected 

 by damp, either from rain without or 

 condensation within, would be liable to 

 decay, if of the former material. They 

 are provided with water-gutters in front, 

 as are all the buildings in the garden, for 

 the collection of rain-water, and keeping 

 the buildings dry. They are heated by 

 4-inch hot-water pipes placed along the 

 front, the boilers being placed in the 

 centre of the ranges, the water flowing 

 from them to the right hand and to the 

 left. They are thoroughly free from damp 

 within, as the ground they are sunk in is 

 a sharp alluvial gravel. 



We would no doubt have tanked all 

 these pits, to save the time and expense 

 of collecting leaves for them ; but in that 

 case the pits would have been of a perma- 

 nent depth ; and as the plants extended in 

 height, they would get broken by coming 

 against the glass. This is avoided by 

 their being plunged in leaves, as, when 

 the plants touch the glass, they are taken 

 out, and the depth of leaves reduced, 

 which could not very readily be done by 

 the tank mode of heating, unless the floor 

 they stood on, or the roof above them, 

 could be elevated and depressed by ma- 

 chinery — both of which, although quite 

 possible, would render them complicated, 

 and liable to derangement. 



Pelvilain 9 s pine-pits. — M. Pelvilain was 

 one of the gardeners to the late King of 

 the French at Meudon near Paris, and his 

 success in the cultivation of pines, of late 

 years, has been reported as being extra- 

 ordinary. When we knew something of 

 French gardening, and were in the habit 

 of seeing it practised, we used to consider 

 a French-grown queen pine of 2 or 3 

 pounds' weight extra good. However, it 

 is not with the culture, but the means 



employed, so far as structures are con- 

 cerned, that we have at present to deal. 



We have not been in Paris since the 

 pine revolution took place, therefore we 

 must take the description and illustration 

 of the Meudon pits from those who have 

 been there. We are informed by " Mira- 

 bile Dictu," a correspondent in "The 

 Gardeners' Chronicle," that M. Pelvilain's 

 pits for young plants are frames or wooden 

 boxes. " These boxes," he says, " are sup- 

 ported by piers of wood about 2^ feet 

 above the ground. The under portion of 

 the boxes is lined with old ship-timber, 

 laid as close as possible to prevent the 

 ingress of steam, and also to keep the soil 

 in which the pines are planted from mix- 

 ing with the stable litter which is em- 

 ployed in heating them." The heat is 

 applied in shape of linings of hot dung 

 round the sides of the pits, and the same 

 material placed in a vault under the beds, 

 but from which it is also carefully sepa- 

 rated by a flooring of boards, upon which 

 the soil is laid in which the pines are 

 planted, M. Pelvilain making it a prin- 

 ciple to exclude ammonia and all other gases 

 from entering his pits. Now, we have 

 here to confess our ignorance how heat, 

 in degree to be at all useful to the plants 

 within, can penetrate through the closely- 

 boarded sides and bottoms of these pits. 

 With the principle of these pits we do 

 not quarrel, but with the material used. 

 For why not use slate, thin pavement, or 

 even plates of thin iron, all of which are 

 conductors of heat, while timber is quite 

 the reverse 1 Or why not use Baldwin's 

 pits, page 432, which are all also of wood, 

 that portion, however, which separates 

 the dung lining from the dung-bed being 

 of open timber-work, for the purpose of 

 more readily admitting the heat? To 

 separate the mould-bed from the heated 

 dung underneath with thick boarding is 

 the height of folly ; and no man having 

 the slightest knowledge of the proper- 

 ties of heat, or of the non-conducting 

 power of timber, would do so. If the 

 exclusion of ammonia and other gases 

 is the only object in view, surely slate, 

 tiles, pavement, or metallic plates, would 

 answer as well. Taking these pits as a 

 whole, we consider them as the very worst 

 that could possibly be conceived. 



The fruiting pits are thus described in 

 " The Gardeners' Chronicle : "— " M. Pelvi- 



