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ether put a few drops of water. Burn brown paper under mouth Place under receiver and exhaust of receiver until filled with smoke. until ether is almost evaporated. Place on plate and exhaust. Note If the pump works well the water that the rare air will not float the will be found frozen. If the pump
smoke and that it falls to the plate. is not perfect the water will be found very cold. The pressure of Exp. 19. Pressure and Volume. the air being removed by the pump, Fill with air to one-half its capacity the ether evaporates rapidly and
a toy balloon or bladder, place unremoves the heat from the water.
der receiver and exhaust. Explain This explains why a room may be the undue expansion. Is this excooled by sprinkling the floor or
periment related to No. 13? Put why it turns cooler after a rain.
a shriveled apple under receiver Exp. 16. A Magic Test Tube.
and note effect upon exhausting the To show liquid condition of air. ether due to the fifteen pounds' pressure, fill a test tube with water. Replace a few drops by ether and
Exp. 20. A Fish Under the Re
ceiver. keeping thumb over mouth of tube insert in a wide-mouthed bottle of
Have the pupils bring you a water and place under receiver.
small live fish. This they will be When the air is exhausted the liquid
most happy to do. Place in a vesether changes to a gas and the test
sel of water and put under receiver. tube rises as by magic. Let the
Exhaust rapidly noting the effort air return to the receiver and the
of the fish to keep from floating. tube suddenly sinks in the water.
Notice the air bubbles escaping from the mouth of the fish.
admitting the air, see how heavy Exp. 17. To Show How Clouds
the fish appears to be, how it sinks are Formed.
to the bottom of the vessel. ExMoisten the inside of a receiver plain to your Physiology class how and exhaust the air. The removal fish breathes air. Refer to of a part of the air removes likewise
Exp. 11. a part of the heat and leaves the temperature of the remaining air below the dew point. This simple ceiver.
Exp. 21. Fountain Under Reexperiment explains the philosophy
Place under your tallest receiver of cloud formation.
(you ought to have several) the bot
tle with jet described in Exp. 6, Exp. 18. Smoke Falls in Thin January number. It should be i or Rare Air.
filled with water. Exhaust and ex
plain the fountain. What pressure May be the valves are dry, or poson the water, in the bottle?
sibly there may be a leak. Attach the pump to a rubber tube connected with good piece of glass tubing entering a tightly corked quart bottle. Exhaust the air for two or three minutes. Then pinch the rubber tube tightly, disconnect the pump and insert the end of tube in basin of water. The bottle should almost fill with water. This is as successful a test as the highpriced mercury apparatus for testing.
Exp. 24. The "Sucker."
This illustrates in a unique manner atmospheric pressure. Pierce with an awl through the center a 3-inch piece of harness leather. Pass a strong cord through the
opening, soak the leather for some Exp. 22. To Fill an Inverted
hours in water when by pressing it Bottle.
closely upon some flat surface and Invert a slender bottle in a cup
pulling the string quickly a weight or in a glass of water and place un
of several pounds may be supder the receiver. Exhaust the air
ported. and on re-admitting it the bottle will appear to suck up the water from the vessel in which it was Exp. 25. The Inverted Glass of placed. This experiment may be
Water. rendered more striking if the upper The following experiment may bottle be supported on a glass tube lead your pupils to question the Law through a closely-fitting cork. of Gravitation. Cut a piece of
writing paper to near the size of the Exp. 23. To Test Air Pump.
top of a glass tumbler. Fill the It may
be wise to halt a little and glass with water, place the paper take your bearings. Possibly some carefully over the glass and invert of the experiments may not come holding the paper in place with the up to the “diagram and specifica hand. Then remove the hand and tions." Test your pump carefully. explain the phenomenon.
Exp. 26. To Make a Siphon Spring
the water you can have the 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.
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 a } or 4 in. hole as indicated in figure. Bend and insert a glass tube of } inor 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
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 1 full of water, then fasten to a hook or nail on the wall, mean
time keeping the lower ends of the fall and rise by placing the mouth tubes closed until A is in position. to the bottle and condensing and Make the opening of the jet tube exhausting the air. in A small so that the vessel does In the next number I shall exnot empty too rapidly. To stop plain how C may be used to make the fountain, plug the lower ends of an amusing Lung Test. the tubes.
(To be Continued.)
Exp. 28. Another Lung Test or the Bottle Imp.
It is with sincere regret that we again state that Prof. Mills is quite ill, and therefore unable to prepare his article on Arithmetic.
" 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 Fiy VI
teachers of Geography will find The Cartesian Diver
Diver costing fruitful and suggestive in that, diusually $1.00 to $2.50 can be made
rectly and incidentally, it gives a in a few minutes and without cost. clear notion of the Chicago DrainBy reference to Fig. 8, C is a small age Canal, the importance, comphial closed by a cork having a slot mercially, of Chicago, Cleveland, cut in the side of the cork and Buffalo, Detroit River, and the weighted down by a small nail or a southern coast of Lake Erie, the screw. The delicate part of the ex- difficulties in the way of utilizing periment is to put just enough wa- the Welland Canal as an outlet to ter into C that it will barely float. the sea, and many other facts with In other words, the specific gravity which progressive teachers should of C must be a little less than that be somewhat conversant. of water. Drop C into a fruit jar This article might well be subor wide-mouthed bottle of water stituted for the more formal geogfilled to within 1 inch of the top. raphy for an entire week, and all Stretch tightly over the top of jar pupils as well as the teacher be a piece of sheet rubber and tie in gainers by the substitution. Inplace. Then by pressure on rub- deed it may well be doubted ber the "diver" will descend but whether the study of Geography ascend with removal of pressure. ever attains its true importance in If you prefer, it may be made to any schools where such supplementary work, as this article sug- Conventional designs and patgests, is not done.
terns, to teach them to be neat and F. B. PEARSON. exact.
Point and line drawing, to THE TEACHING OF DRAWING. strengthen the muscles and to
teach the eye to see straight. ( Answers to questions in January MONTHLY. By Ida G. Doute, St. Marys, 0.)
5. (a) Yes. (b) By overdoing 1. Because the average teacher it. (C) Yes. does not know what, or how to 6. There are very few. draw.
7. (a) Perspective should be 2. The special purpose of draw- taught by rule in the grammar ing in primary grades is to teach grades but not in the primary. (6) pupils to see. In the intermediate, Shading should not begin until the to see and put down what they see. pupil is able to represent form by In the grammar not only to teach outline and that correctly. them perception and expression 8. (a) Where it enables the pupil but exactness.
to put down what he sees and 3. The most profitable material thinks. (b) No. (c) Not necessarily. is that which they can see and get. 9. It should cultivate the imagDo not have them draw tubs, buck- ination also. ets, elephants, flowers and such 10. First have them know a few things from memory, as that is of the principles of drawing or art. teaching drawing with your eyes Then practice faithfully and dilishut. Let them draw what they can gently. But it can never be a sucsee from the objects.
cess unless they have some love for 4. Drawing of types is profitable the work. The only way is to go only as it comes up in their work. to work and draw.
0. T. R. C. DEPARTMENT.
It will be queer to change our name BY J. J. BURNS.
for it when we talk of the glories Hopkinsville, Ky., Jan. 1, 1898.
or the shames of the century unless The year died in the night. we practice betimes on the “TwenThree years from this morning tieth.” I wish we had some short those of us who still walk in the word in English for our hundredlight will think and perhaps say, year period, like hour, day, week, “The century died in the night.” month.