Handy man's workshop and laboratory . ident that the height of the mercury inthe tube responds to the variations in the weight of the atmo-sphere pressing on the bath of mercury. The relations of themovements of theglass to theweather are of coursesimple enough. Whenthe atmosphere isheavy it causes themercury column torise, indicating fairweather; and con-versely when the at-mosphere is tinderlow pressure the mer-cury column sub-sides, indicating theapproach of a the construc-tion of a home-madebarometer, purchaseabout three-quartersof a pound of mer-cury, a glass tubethree feet in l
Handy man's workshop and laboratory . ident that the height of the mercury inthe tube responds to the variations in the weight of the atmo-sphere pressing on the bath of mercury. The relations of themovements of theglass to theweather are of coursesimple enough. Whenthe atmosphere isheavy it causes themercury column torise, indicating fairweather; and con-versely when the at-mosphere is tinderlow pressure the mer-cury column sub-sides, indicating theapproach of a the construc-tion of a home-madebarometer, purchaseabout three-quartersof a pound of mer-cury, a glass tubethree feet in lengthand closed at one end,and a small glassreceptacle four orfive inches long. This should be large enough to take the endof the long glass tube, allowing a quarter of an inch or so allaround. The wood necessary for the construction of the frameis likely to be found in almost any house. It is desirable that thiswork should be taken in hand in the first place. To make theframe take a board about three feet three inches long- and four. Fig. 166—Inserting the tube in themercury receptacle 186 HANDY MAN S WORKSHOP AND LABORATORY inches wide; make the whole nice and smooth. Now cut twostrips of wood, say thirty inches long and one and a quarter inchesin width. Screw these to the board far enough apart to allowthe glass tube to be dropped in between them, at the same timetaking care to place them four inches from the bottom of the board. Along the bottom ofthe board fasten a strip ofwood sufficiently wide to sup-port the glass two pieces of wood toeither side of the board, theseto run up to where the twolong strips terminate. Inthis way will be formed thethree sides of a little box. Apiece for the top of the boxmust have an archwayscooped out in the center toallow for the passage of thetube. A square piece of thinwood may be cut to form thelid of the box. After apply-ing some stain to give thewood a finish the frame iscomplete. i The next matter for con-sideration i
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Keywords: ., book, bookcentury1900, bookdecade1910, booksubjectworkshoprecipes
