214 



CASSELL'S POPOLAE GARDENING. 



In like manner, broken squares can te taken out and 

 replaced by new ones, by any unskilled workman. 

 Fig. 33 is a section of one of the sash-bars : o is the 

 rafter-bar, -which is composed of iron in the shape of 

 ii T. On these, long strips of bituminised felt, dd, 

 are laid for the reception of the glass, similar strips 

 being also placed between the upper side of the glass 

 and the covering cap *. By means of hard white 

 metal nuts, c, the whole can be secured in position and 

 Hghtened or slackened at pleasure. The glass is 

 thus held securely between the strips of felt, which, 



the annexed illustrations, no putty is required, and 

 nothing but lead and glass is exposed to the atmo- 

 sphere; consequently, the usual expense of outside 

 maintenance is reduced to a minimum. Repairs of 

 accidental breakage can be readily effected, as there 

 are no fastenings or screws to remove at any time, 

 and, although no putty is used 

 and no breakages arise from 

 change of temperature or vibra- 

 tion, the roof is air-tight, water- 

 tight, and capable of resisting 

 storms. The lead strips. Fig. 

 34, are made in lengths up to 

 eighteen feet, and can be fitted 

 to wooden or other sash-bars ; Fig. 35, showing a bar 

 ready for glazing, and Fig. 36, the same when the 

 work is finished. By the removal of the tonguea 



Fig. 34. 



Fig. 33.— Beard's System. 



being a non-conductor of heat, prevents its passage 

 from the internal to the external bars. The former, 

 therefore, do not become rapidly cooled in cold wea- 

 ther, and there is consequently decreased danger of 

 drip from condensed moisture. The squares of 

 glass employed are thirty inches long and twenty 

 inches wide, and may either be placed edge to edge, 

 which is always done in the fronts and ends, or 

 lapped vertically, the covering bars in the latter 

 case being made of the same length as the squares. 



Mr. Beard's system of glazing may be applied to 

 any kind of house — span-roof, curvilinear, or lean-to 

 — but those for which it is most frequently used are 

 generally made with fronts from two to four and 

 a half feet high, provided with hollow columns at 

 every five feet, which serve to carry off the water 

 collected in the troughing that also forms the front 

 plate from which the rafters spring. The columns 

 can be secured either to brick or stone-work at their 

 base, or to iron or wood where the house is not in- 

 tended to remain as a fixture. The whole of the 

 iron-work is enamel-painted, and the paint is ren- 

 dered very durable by being well baked. 



Simplex Glazing — Smith's System. — This system, 

 like the preceding, is extremely simple and economi- 

 cal, and, judging from the materials used, promises to 

 become one of the most useful methods hitherto in- 

 troduced to the public. As will be gathered from 



Kg. 35. 



Fig. 36. 



from ordinary sash-bars, as in Fig. 37, existing houses 

 can easily be re-glazed upon the Simplex principle. 

 It will be observed that the lead strips, which are 

 the special feature of the system, are fastened to the 

 wood- work by means 

 of three-quarter-inch 

 copper tacks, and 

 grooves on either 

 side of the sash-bar 

 are provided for car- 

 rying off condensed 

 moisture ; but the 

 utility of these is 

 doubtful, as owing 

 to their position they 

 may become clogged 

 with the dust and other matter which soon accumu- 

 late in hot-houses ; this, however, is of little, conse- 

 quence, as existing improved modes of ventilation 

 now carry off moisture before it has time to condense 

 and drop from the sash-bars. 



The manufacturers, Messrs. Grover and Co., Bri- 



Fjg. 37. 



