Popvlar Science Monthly
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��bricks to make the front opening. On top of this lay ten more bars imbedded in the mortar, then lay five layers of brick, finishing the top by rounding it oflf with mortar.
When this is completed the incinerator will have a fire grate below and another grate above entirely surrounded with bricks. The second grate forms a receptacle for garbage. The mortar should be made of slacked lime and sharp sand. — Ronald F. Riblet.
Holder for the Starting Crank of an Automobile
ON some older types of automobiles no provision was made for securing the starting crank when it was disengaged. The
���BEARING
The pin on the jaw-clutch that slips into a notch for holding crank in an upright position
arrangement shown herewith for holding the starting crank is easy to make and apply and will be found very effective. The sketch shows the usual jaw-clutch shaft held in a bearing fastened to the underside of the radiator channel.
The crank-holding device consists of a hardened steel pin driven in the large part of the clutch shaft so that it will engage the slot plate when the spring forces the shaft outward. When cranking the motor the pin clears the slot plate. The pin is either a drive fit in the clutch shaft or is threaded. If the shaft is hardened it will be necessary to anneal it before trying to drill the holes. — W. Burr Bennett.
Cut Your Ice Silently and Easily With a Needle and Thimble
A BLOCK of ice can be split into small pieces in a very short time by the use of a needle and thimble, without the trouble of putting the ice in a bag and pounding it or the muss attending the shaving or picking process.
A rather coarse needle of the variety used for hand sewing, or a small darning needle,
��and a thimble are the only tools required. Hold the needle between the thumb and index fmger of the right hand, and with the thimble on the second finger of the same hand press the needle firmly and steadily into the ice. In a second or two the piece of ice of the size desired will quietly crack off. This method has its silence to recommend it. — C. B Whitehouse.
��A Built-in Writing Desk Made from a Bre^d Board
WHEREVER a compact writing desk is needed this type can be used to ad- vantage, especially in the summer cottage. The desk itself is nothing more than a flat board. A bread board 16 by 22 in. woulc'. be about as satisfactory as anything. First decide on the location. If, as in a summer camp, there is no plaster and the studs are exposed, the position of the desk may be between tv, o of the studs. If there is plaster, it will have to be broken through between two studs. About 30 in. above the floor and between the studs nail another piece the same size as the studs like a header. From this cross-piece hinge the bread board as shown in the illustration and fasten it to a chain on one side to hold it in a horizontal position when it is down. On the inside of the desk top fasten a blotter, and adorn the outside with a picture. The studs are usually spaced about 18 in. on
���The built-in writing desk as it ap- pears when it is open and closed
centers so that a clear space of about 16 in. will be in the wall between them. The back of this may be used as a space for a rack for papers and hooks for pens and pencils and place for ink, etc. The illustration furnishes a suggestion as to what can be done and how the desk looks when it is closed and out of the way. — Harold V. Walsh.
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