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This is a thing to be avoided, for, in districts where 

 coal is dear, it becomes a grave consideration how to 

 economise in the consumption of this useful material. 

 If the flue takes its first course along the bottom of 

 the wall, the heat of course will be strongest there, 

 but surely it would be better to place some non-con- 

 ducting material in contact with that portion of the 

 flue, which, if properly managed, would supersede the 

 necessity of the trellis ; the best substance with 

 which we are acquainted for this purpose is dry and 

 new sawdust. An objection may here, however, be 

 started, that this in the neighbourhood of the fire 

 would be liable to ignite. Here, then, for a short 

 space, some other substance might be used ; and 

 pounded glass, the refuse of the glass-house, would 

 perhaps answer the purpose. If we mistake not, this 

 material was employed by Mr. Forrest some years 

 since in the houses at Syon, where, we believe, the 

 main piping from the steam apparatus, which had to 

 travel some distance before branching into the respec- 

 tive houses, was imbedded in pounded glass. The 

 next point in Mr. Irving' s practice, to which we would 

 allude, is the depth of soil he deems necessary. Three 

 feet of soil may do in our southern counties, but will 

 oftener produce failure than success in our more nor- 

 thern ones. Half a yard of this depth, moreover, is 

 composed of strong clay ! Surely this is not to be 

 recommended for general practice. Although peach 



