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ether put a few drops of water. Place under receiver and exhaust until ether is almost evaporated. If the pump works well the water will be found frozen. If the pump is not perfect the water will be found very cold. The pressure of the air being removed by the pump, the ether evaporates rapidly and removes the heat from the water.

This explains why a room may be cooled by sprinkling the floor or why it turns cooler after a rain.

Exp. 16. A Magic Test Tube.

To show liquid condition of ether due to the fifteen pounds' pressure, fill a test tube with water. Replace a few drops by ether and keeping thumb over mouth of tube insert in a wide-mouthed bottle of water and place under receiver. When the air is exhausted the liquid ether changes to a gas and the test tube rises as by magic. Let the air return to the receiver and the tube suddenly sinks in the water.

Exp. 17. To Show How Clouds are Formed.

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sel of water and put under receiver. Exhaust rapidly noting the effort of the fish to keep from floating. Notice the air bubbles escaping from the mouth of the fish. On readmitting the air, see how heavy the fish appears to be, how it sinks to the bottom of the vessel. Ex

a fish breathes air. Refer to Exp. 11.

Moisten the inside of a receiver plain to your Physiology class how and exhaust the air. The removal of a part of the air removes likewise a part of the heat and leaves the temperature of the remaining air below the dew point. This simple experiment explains the philosophy of cloud formation.

Exp. 18. Smoke Falls in Thin or Rare Air.

Exp. 21. Fountain Under Receiver.

Place under your tallest receiver (you ought to have several) the bottle with jet described in Exp. 6, January number. It should be filled with water. Exhaust and ex

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Exp. 26. To Make a Siphon the water you can have the spring Spring.

flow at regular intervals of from a minute or two to a half hour if you so desire. Use the rubber tube to show pupils the action of a plain siphon.

Exp. 27. To Make a Constant Fountain.

A

Fig.VI.

To illustrate the subject of intermittent springs in geography, arrange apparatus as shown in Fig. VI. Select a good heavy bottle holding say a pint. With a broken file or brass tube and emery powder bore aor in. hole as indicated in figure. Bend and insert a glass tube of in. or even larger diameter. A small tube does not succeed well because of capillarity. Place a bucket of water two or three feet above the bottle and by means of a small rubber tube siphon the water into the bottle. By putting a wood plug in the lower end of the rubber tube to regulate the flow of

Fig. VII.

Your pupils will work out No. 27 for you and be delighted with the success of the experiment. If the fittings at A are air tight the fountain will flow until it is empty. Fill A full of water, then fasten to a hook or nail on the wall, mean

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Fig. VIII.

The Cartesian Diver costing usually $1.00 to $2.50 can be made in a few minutes and without cost. By reference to Fig. 8, C is a small phial closed by a cork having a slot cut in the side of the cork and weighted down by a small nail or a screw. The delicate part of the experiment is to put just enough water into C that it will barely float. In other words, the specific gravity of C must be a little less than that of water. Drop C into a fruit jar or wide-mouthed bottle of water filled to within inch of the top. Stretch tightly over the top of jar a piece of sheet rubber and tie in place. Then by pressure on rubber the "diver" will descend but ascend with removal of pressure. If you prefer, it may be made to

"FROM THE LAKES TO THE SEA."' To the Editor:

An article with the above caption may be found in the "Review of Reviews" for November, which all teachers of Geography will find fruitful and suggestive in that, directly and incidentally, it gives a clear notion of the Chicago Drainage Canal, the importance, commercially, of Chicago, Cleveland, Buffalo, Detroit River, and the southern coast of Lake Erie, the difficulties in the way of utilizing the Welland Canal as an outlet to the sea, and many other facts with which progressive teachers should be somewhat conversant.

This article might well be substituted for the more formal geography for an entire week, and all pupils as well as the teacher be gainers by the substitution. Indeed it may well be doubted whether the study of Geography ever attains its true importance in any schools where such supple

mentary work, as this article suggests, is not done.

F. B. PEARSON.

THE TEACHING OF DRAWING.

[Answers to questions in January MONTHLY. By Ida G. Doute, St. Marys, O.]

1. Because the average teacher does not know what, or how to draw.

2. The special purpose of drawing in primary grades is to teach pupils to see. In the intermediate, to see and put down what they see. In the grammar not only to teach them perception and expression but exactness.

3. The most profitable material is that which they can see and get. Do not have them draw tubs, buckets, elephants, flowers and such things from memory, as that is teaching drawing with your eyes shut. Let them draw what they can see from the objects.

4. Drawing of types is profitable only as it comes up in their work.

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7.

(a) Perspective should be taught by rule in the grammar grades but not in the primary. (b) Shading should not begin until the pupil is able to represent form by outline and that correctly.

8. (a) Where it enables the pupil to put down what he sees and thinks. (b) No. (c) Not necessarily. 9. It should cultivate the imagination also.

10. First have them know a few of the principles of drawing or art. Then practice faithfully and diligently. But it can never be a success unless they have some love for the work. The only way is to go to work and draw.

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