SOME RECENT IMPROVEMENTS IN THE MECHANIC ARTS. 257 



SCIENTIFIC MISCELLANY. 



SOME RECENT IMPROVEMENTS IN THE MECHANIC ARTS. 



BY F. B. BROCK, WASHINGTON, D. C. 



Novel Reversible Window. — A recent invention provides a window, the 

 sash of which slides up and down in the usual way with counterweights passing 

 over pulleys A portion of the length of the window jambs is a pivoted swing- 

 ing frame, so that both sashes may be run up into the frame, and swing out 

 horizontally or reversed, as desired. The swinging frames are mounted on hoi 

 low pivots provided with cross-pintles and rollers, over which the sash-cords pass. 

 A spring catch in one of the side frames, operated by a lug on a rod, engages a 

 notch 111 the sashes. The cords have an apertured plate to prevent twisting. 

 The swinging frames are grooved to receive the sashes. 



Fire Proof Curtain for Theatres. — A recent German invention has 

 been gotten up by Herr Von Falkenhausen, for separating the stage from the audi- 

 torium in theatres in the event of the breaking out of a fire. The curtain, which 

 is closed at the sides and open at the bottom, is secured at the upper end to a 

 perforated water-pipe. The other end is rolled upon a roller stationed above and 

 in front of the water pipe, so that when the water is turned on the weight of the 

 wet curtain nearest the water-pipe will tend to unroll the curtain until it falls 

 down. 



Electric Flat-Iron. — This novel flat iron is chambered out near its smooth- 

 ing face, forming a cavity for the reception of an electrical resistance, the latter 

 being connected by suitable wires with a galvanic battery. The face of the flat- 

 iron is heated by the radiation from the electrical resistance. A layer of non-heat- 

 conducting material is placed above the cavity in the iron to confine the heat to 

 the face of the iron. 



Wood-Pkeserving Composition — A late invention mixes in the following 

 proportions, viz: Linseed oil, one gallon; common salt, four ounces; saltpetre, 

 two ounces; turpentine, one pint, and applies while hot. It is used for oiling 

 fellies, and at the same time producing tightly-fitting tires. iNIay also be applied 

 to buckets or casks which are to stand in the sun, to prevent shrinkage or warp- 

 ing. 



Electric Incandescent Lamp. — This invention consists in a novel mode 

 of affixing and seahng luminant carbon loops and their circuit wires vacuum-tight 

 in the globes of electric lamps viz : first, immersing the tubes and wires in molt- 

 en metal, and causing the same to rise in the tubes and around the wires; second, 

 retaining the column of metal in said tubes and raising them out of the molten 

 mass ; and finally allowing the charge in the tubes to solidify. 



