Fastening Mats or other Sash- Coverings. 109 



removed, and light admitted in the morning. In houses heated 

 by combustion this can in some measure be guarded against, 

 but in those heated by fermenting substances the evil becomes 

 aggravated ; and to structures heated by such materials I cannot 

 see the utility of this application, as economy here cannot be the 

 motive; materials capable of maintaining a sufficient temperature 

 during a sunless winter's day will in all cases be sufficient 

 during night, when a fall of temperature is so beneficial ; yet 

 these structures are covered more than all others, the evils not 

 becoming so apparent, possibly because the plants there con- 

 tained are generally but of annual growth. The debilitating 

 effect of covering houses heated by fire is particularly per- 

 ceptible in vineries, probably from the position that the plants 

 occupy in the house. Thus, were economy not a material ob- 

 ject, heating power at command, and the good of the plants the 

 only consideration, I certainly should add no covering to the glass 

 roof. The scientific may well smile at the homely argu nents 

 here used, but they are level to the capacity of many interested, 

 who (like the writer) could not discuss them in a more phi- 

 losophical manner. 



Folkstone, January 14. 1842. 



Art. IX. On a Mode of securely fastening Mats or other tvove 

 Coverings on the Sashes of Pits and Frames. By H. C. Ogle. 



The following is the description of a method of securely 

 fastening mats or other coverings on pits and frames : it is su- 

 perior to any other mode I am acquainted with, and, I believe, 

 requires but to be known, to be generally adopted. It effectually 

 answers the purpose it is intended for, is not expensive, is easy 

 of application, and entirely obviates the necessity of driving some 

 scores of nails every night, or of having a quantity of boai ds 

 lying in all directions in the melon ground, for the purpose of 

 placing on the covering of the frames, to prevent its being 

 blown away. The breakage of glass by this latter method is 

 usually a large item in the glazier's account, which the plan I 

 am about to describe will be a saving of. This is of great 

 importance, independently altogether of its other merit. Theie 

 are at this place about fifty lights fitted with wires, and I know 

 of no objection to them whatever. 



Three pieces of iron, of the form of fg. 5. a, are screwed on 

 to the end of the frame, one piece at the top, another at the 

 bottom, and the other in the middle, so that the top of the iron 

 is about 2 in. above the light; on the opposite end, three pieces, 

 of the form of c, are screwed on at the same distances as a; b is 



