6jJ AIRTIGHT HTNGE. 



fastened : E F, a chain formed of brass plates rivetted to- 

 gether, windhig round in a ^;roove from off one fold of the 

 screen on to the other,the contrary way to the leather, so as 

 mutually lo keep each other stretched tight, the chain 

 windinj^ on when the leather winds off, and vice versa; 

 thus they move smooihly round one another. G, fig-. 10, 

 a piece of brass (left out in the last rls^'ure in order to 

 show the chain) screwed to the centre of each curve of 

 the screens which forms the liinge, and by keeping the 

 folds of the screen at their proper distance secures the 

 easy action of tlie chains and leather, and prevents their be- 

 ing overstretched. H H, a line of green twist fastened 

 along the bottom of the screen, and passing through a sta- 

 ple on the joint at G, serving to keep the screen airtight on 

 the tloor. 



Fig. 11 is an elevation showing the top and bottom joints, 

 ■with the same letters of reference. 



REMARK, 



It would frequently be a desirable convenience to have 

 the doors in the interior parts of a house so contrived, as4o 

 open either inwardly or outwardly. Mr. Furniss's hinge 

 would effectually answer this purpose: but it would be pro- 

 per to have the opposite edge of the door padded, as it 

 could not be made to fit tight, and there must be no ledge 

 for it to abut against. A piece of leather nailed on it, and 

 then stuffed with wool or horse-hair, might be so adapted, 

 as to make this side airtight also, at the same time that it 

 would open and shut freely. It is probable however, that 

 some inconvenience might be felt in applying Mr. Fur- 

 niss's hinge to a door, particularly if large and thick, 

 from the strain upon it by the weight occasioning it to 

 drag. The best remedy for this would be a. couple of 

 castors in the foot of the door, one near each end. C- 



X. 



