60 
THE CONSERVATORY. 
For the bed at the back for larger trees, where two ranges are contemplated, the afore- 
named soils are mixed in equal quantities, adding some sandy gravel, the mixed earths , 
to be laid about two feet thick, and then trod evenly over ; near the top the chopped 
turf is omitted, and sand substituted for the gravel. The front bed, for smaller 
plants, equal quantities of bog and loam are used, with some gravel, until within one 
foot of the surface. The gravel is then omitted, and sand used in lieu of gravel, 
except in places intended for clumps of Camellias, and there two parts of loam and 
one of bog is added quite up to the surface. 
Such is the general direction for preparing the soils for permanent beds in a conser- 
vatory of the highest class. At the time when the plan was first adopted, little was 
known of the analysis of soils, and as to loam, the term was indefinite as possible. 
Even at the present day, when chemistry has taught the certain investigation by 
re-agents which cannot deceive, practical men cannot command the precise material, 
hence loam must be determined alone by a thorough investigation of texture and 
temperament, when wet, dry, in pots, and in the open ground. If the colour be a 
fair hazel, the sandy constituent be fine and soft, and the state when dry neither 
harsh nor cracking into fissures, the earth may be reckoned safe, and congeuial to 
the plants. Bog-earth — that is, the lieath-soil of moors — may generally be trusted, 
but it should always abound with white siliceous sand. 
One further remark must be attended to ; it is the following : — In the Grange 
conservatory, after allowing the ground to settle, at the time of planting, “ loam, 
sand, bog turf, gravel, and potsherds, were used under or about individual plants, as 
was thought necessary or agreeable to their different natures.” 
We believe that the article of charcoal chips, about the size of the small pot- 
sherds usually employed, would always be fomid a most useful substitute ; they hold 
water pertinaciously, yet never need be wet; and the screenings, or dust of the 
same material, would be found a sweet and indestructible meliorater of texture. 
Bone- dust, bone superphosphate, might also be safely and efficaciously employed; 
but we lack the data and facts whereon to assume a proper standard. Gardeners 
have never studied these matters : but by the stride that science is making in agricul- 
tural practice, we judge that it will not be long ere she lend equally efficient assist- 
ance to the garden. 
Our limits will not permit any reference to the noble list of plants which con- 
stitute the inhabitants of grand conservatories : they rank among the very finest of 
Southern Europe, the temperate climes of America, of the East, China, and New 
South Wales ; but as to the mode of heating, there can as yet be little question that, 
from its great equability of radiation, hot water, worked by the saddle boiler, or some 
such apparatus, where every particle is operative, must be preferable, or even indis- 
pensable. And, finally, it may be stated, that a good cast-iron boiler will last 
twenty years ! 
