Marcu 2", ISjo.] 



KNOWLEDGE 



271 



(Pur fubrntors' Column. 



We give here, xceeh iy tcceJi, a terse defcription 0/ ancU of the many 

 inventions as tr« thiji): may he of ttse to our readers. Where it is 

 possible, the nttmher of the patent is quoted, to enable those who 

 desire fuller information to procure the spccijication from the 

 Patent Offiee in Cursitor-street, Chancery-lane. We shall, gene- 

 rally speaking, connne ourselves to the more recent inventions; bid 

 it often happens that an article comes under our notice which, 

 although not quite novel, is worthy of mention for its utility and 

 ingenuity. In such a ease we should not hesitate to refer our 

 readers to it. And while we thus increase the interest of our pages, 

 tve at the same time assist the inventors by giving greater publicity 

 to their ini'entions (Knowledge being a popular magazine) than 

 is accorded by the most excellent trade journals 



REGISTER STOVE. 



[Patent, No. 7,125. 1881.]— Mr. Frodc-rick lirown, of the firm of 

 Hrown & Grcou (Limited), Luton, lU'dfordshire, has patented a 

 now form of stovo, in whicli a largo firebrick ovcrliangs tlio b;ick of 

 the firo. It has also a solid brick or iron bottom, and a p;rated back. 

 A little below tlie bottom is another plate, the space between the 

 two forming a chainbor in which air entering from tlie front 



BIRD-CAGE. 



[Patent, No. 2,577. ISS-t.]— Mr. F. Ostler, of Yeovil, has 

 patented an improved cage in which to exhibit canaries and other 

 birds at cage-bird shows, which will, doubtless, bo welcomed by 

 those who are in the habit of exhibiting birds at these shows, whicli 

 are now held in all parts of the kingdom. The invention does away 

 with the use of wrappers, and affords protection to the birds from 

 draught and cold when travelling to and from an exhibition. The 

 device is as follows; — A metal slide, hinged in the middle so as to 

 fold np, and with perforated spaces for admitting air to the birds, 

 is fitted to grooves in the edges or corners of the cage, so as to 

 cover the wire front, and afford the necessary protection to the 

 birds. 







/.>.^t:v"^ 



i^F^ia/iiiiiiiiiiy 





becomes heated. This chamber communicates with the grating at 

 the back, whence a constant current of hot air is discharged through 

 the back grating into, upon, and over the top of tlie Hre, the result 

 being a more perfect combustion, with tho production of little or 

 no smoke, and a proportionately increased heating power, the fire, 

 too, presenting a cheerful aspect. The accompanying illustrations, 

 section and perspective view respectively, will help to explain the 

 patent. 



TUE ItECTOLIXE. 



This is a useful and simple piece of apparatus, introduced 

 by Messrs. Wolff & Son, of Great Queen-street, Loudon. Its 





-^ 



Fig. 2. 



The Rectolinc. 



The cage ia made with a double top, with a space between its 

 two parts, an aperture being cut in the side of the cage leading 

 into the space. On the arrival of the cage at an exhibition, the 

 metal slide is removed from the front of it, folded up, and placed 

 in this space, and is thus ready at hand for placing down the front 

 again as soon as the exhibition is over and the birds are ready to 

 be returned to their owner. The invention may be better under- 

 stood byreference to the accompanying illustrations. Fig. 1 shows 

 the metal slide in its position in front of the cage. Fig. 2 shows 

 the metal slide folded and placed in the space at the top of the 

 cage. The cage is already spoken highly of, more particularly on 

 account of the time saved by its adoption. 



object is to assist the beginner in his effort to obtain correct pro- 

 portions in copying drawings, prints, &c. Tho work to be copied is 

 pinned to the back of a separate wooden frame — another similar 

 frame is hinged on to a drawing-board. A sheet of paper is cut to 

 the size of the board and pinned on, and tho attached frame is 

 allowed to fall on to it. The copy and blank paper are alike divided 

 into squares by means of threads stretched across the frames. The 

 outline of the drawing can then be easily copied by following the 

 detail contained in each square, letters and numbers being stamped 

 or printed on the frames to indicate the corresponding spaces. 

 The outline being completed, tho frame is raised and the drawing 

 completed. 



