AQUICK and accurate way of obtaining an impression of the holes already drilled in a flange when a new flange or cap is to be fitted to it, is to rub a piece of chalk down into the hole so that the edge will scrape off a small amount, forming a bead of chalk that is slightly raised above the surface of the flange. On the flange thus prepared the new flange is laid in the exact position in which it is to be bolted. On removing the chalked flange an accurate tracing of each hole will be found on flange. These circular tracings can be centered and drilled and they will be sure to mate the holes in the other flange when it is replaced for bolting. Magnetic T-Square By William Grotzinger WHEN much hatching is to be done there is always a tendency to move the T-square out of position because it is necessary to hold the T-square and at the same time to manipulate the triangle and the ruling pen. To eliminate this trouble the writer took two small electro-magnets out of an old door bell, and fastened one on each end of the head of the T-square, taking care to get the magnet cores on a line with the edge of the head. Then a piece of thin iron band was fastened to the edge of the drawing board with several small screws. The magnets were connected in series with a battery and switch. When turning on the current, the magnets will hold the T-square firmly against the drawing board. Then all one needs to do is to attend to the triangle and the pen. This will eliminate slipping of the T-squareand make for accurate work.