It would be advisable, if possible, to have the part of the needle that touches the contact points, as well as these points, of platinum, as the arc that is likely to be formed will not destroy the platinum as easily as it will the brass. A small wooden containing case can now be made and the thermostat is complete. There should be a large number of holes drilled in the sides, ends and back of the case so that the air inside may be always of the same temperature as the outside air.
In adjusting, testing, or calibrating your thermostat, make sure that it is in the same position that it will be in when in use.
The connections of the thermostat for ringing one bell when the temperature rises or falls to a certain value, are shown in Fig. 11. The connections of the thermostat for ringing one bell when the temperature rises to a certain value and another bell when the temperature falls to a certain value, are shown in Fig. 12. The complete thermostat is shown in Fig. 13.
A Tailless Kite
Plan and Dimensions for Kite
The frame of a 3-ft. kite is made of two sticks, each 3 ft. long. These are tied together so that the cross stick will be at a distance of 15 per cent of the full length of the upright stick, from its end, or in this case 5.4 in. The sticks may be made of straight grained pine, 3/8 in. square, for small kites, and larger hardwood sticks, for larger kites.
The cross stick is bent into a bow by tying a strong cord across from end to end. The center of the bend should be 4-1/2 in. above the ends. The bend is shown in the sketch. Connect all four ends or points with a cord, being careful not to pull the bend of the cross stick down, but seeing that it remains straight across the kite. When this is done the frame is ready for the cover.