Mechanics for young America; how to build boats, water motors, wind mills, searchlight, electric burglar alarm, ice boat ..etc.; the directions are plain and completeReprinted from Popular mechanics . , thuscausing the air in F to contract and conse-quently opening the circuit through C. Ifat any time the furnace should overheat,the raising of A, on which is grounded awire from a signal bell upstairs, will makea circuit through the bell by means of thepoint Z and wire leading therefrom. Thisbell also serves to tell me whether H hasdropped or not. This same device of regu-lating the draft D can
Mechanics for young America; how to build boats, water motors, wind mills, searchlight, electric burglar alarm, ice boat ..etc.; the directions are plain and completeReprinted from Popular mechanics . , thuscausing the air in F to contract and conse-quently opening the circuit through C. Ifat any time the furnace should overheat,the raising of A, on which is grounded awire from a signal bell upstairs, will makea circuit through the bell by means of thepoint Z and wire leading therefrom. Thisbell also serves to tell me whether H hasdropped or not. This same device of regu-lating the draft D can be used to regulatethe damper, found on the coal doors of mostfurnaces, by simply fusing a platinum pointon the other side of M and changing thecord which is attached to D. A two-contactswitch could also be inserted to throw con-nections from 2 to 3. It would work in thismanner: The damper door, of course, whichkeeps a low fire, would be up in a positionsimilar to D; on the furnace cooling toomuch, connection, due to contracting of airin F, would be made through 3 and C, caus-ing H to drop, thus closing door. This sim-ple device worked very well all last winterand gave me no trouble FIG. 2 If you cannot readily procure a U-tube,you can make one, as I did, and the workis interesting. The U-tube is constructed in the followingmanner. A glass tube is closed at one is done by holding the tube in onecorner of a gas flame, somewhat near thedark area (A, Fig. 2), and constantly turn-ing the tube, when it will be found that theglass has melted together. Now, after itis cool, about 3 or 4 inches from the sealedend, the tube is held steadily so that theflame will heat one small portion (B, ). After this small portion is heated blowinto the tube, not very hard, but justenough to cause tube to bulge out. Allowto cool. Then reheat the small bulged por-tion, blow quite hard, so that the glass willbe blown out at this point, forming a smallhole. Now insert about a ha
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Keywords: ., bookcentury1900, bookdecade1900, bookp, booksubjectindustrialarts
