coal, iron, etc., should be presented to the child in all the stages of their development. Such material systematically arranged can be furnished only by the museum. The weaving of material, the tools and utensils used by other peoples, such as mentioned in the "Seven Little Sisters" and "All Around the World," are illustrated by the real objects furnished by the museum. The different modes of transportation and the homes of people in foreign lands about which the children read are shown by excellent stereoscopic pictures.

MATHEMATICAL AND PHYSICAL GEOGRAPHY.

Collection 1565.-Advanced Geography-Expansion by Frost.

Apparatus: Test tube, copper beaker, cork. Fill test tube full of water, cork securely. Put into the beaker some cracked ice and salt, one-third salt, two-thirds ice. Set test tube upright into freezing mixture, put beaker on newspaper on desk. Wrap beaker in a towel to exclude heat that would waste ice. What occurs as the water in test tube freezes? Have pupils seen sidewalks raised by frost in the winter time?

Collection 1566.-Atmospheric Moisture.

Apparatus: Two-ounce flask, cork, some ice water, some hot water. Fill flask with ice water, cork securely. Invert and let flask stand two or three minutes on desk. Let pupils note formation of dew. Whence came the dew? Now empty flask and refill with hot water. Repeat as before. Note that no dew is formed. On what does formation of dew depend? Will hot air or cold air hold most moisture? If out of doors it is cold, try putting flask of ice water out of window. Let pupils see that cold air will not form dew in contact with cold flask, while hot air will do so.

Collection 1569.-Cloud Formation.

Apparatus: Two-ounce flask, test tube holder, Bunsen burner. Fill flask twothirds full of water and hold over flame till the water boils. Remove flask and hold at open window for a moment. Let pupils see cloud of escaping steam. Have pupils seen such clouds before? (Steam escaping from engine exhausts.) Bring flask into room-cloud disappears. Why so? Can pupils tell why a morning mist disappears as sun rises? What is dew? Hoarfrost? Their cause?

Collection 1576.-The Seasons.

Apparatus: The tellurian. This can be used with profit to make clear to pupils the inclination of the earth's axis, the varying length of day and night, the difference of temperature between day and night, the succession of the seasons, the equinoxes,

etc.

Mathematical and physical geography in the higher grades are considered by almost all teachers the most difficult part in the whole study of geography to present to the children intelligently and intelligibly. It is, if we teach them abstractly. We can not give the children clear ideas and permanent impressions of the shape of the earth, its rotation, directions, change of seasons, cloud formations, the cause and direction of winds, etc., through the textbook or verbal description. The children must see these processes by means of simple apparatus such as the museum furnishes, and the experiments with such apparatus should be performed by the children under

the guidance of the teacher. The whirling table will give the children a better idea of the true shape of the earth than the orange in the textbook. The real compass, not a picture, should be used by the children to determine directions. The simple apparatus of the collection given in the extract from the catalogue, if operated by the pupils, will give them vivid concepts of expansion by frost, atmospheric moisture, and cloud formations. No better device to present the difficult subject of the change of seasons can be found than the tellurian, which makes clear to the children the inclination of the earth's axis, the varying length of day and night, the difference of temperature between day and night, the succession of the seasons, the equinoxes, etc.

Of seacoast, erosion, volcanic action, geysers, divides, canyons, falls, and cataracts, of glaciers, of plains and deserts, no text or verbal description can give the children concepts clear and strong enough. Neither can this be done by the small, flat, illustrations in our textbook. We have excellent stereographs representing them. These stereoscopic pictures do not show flat photography, but supply double vision, giving three dimensions of a detailed diagram instead of two. The child, looking at a scene through the stereoscope, points

not at places on the flat view, but at things and places far behind it, and when he looks into the depth of the landscape he sees them all in their proper proportion and true relation.

SETS OF 15 STEREOSCOPIC VIEWS.

To give opportunity for a more intensive study of some of the more important topics of physical and commercial geography, sets of 15 views, each card showing the same picture, are furnished by the

museum.

FIG. 23.-German castle.

A picture with holder is given to each pupil or each two pupils of a class-every room in the St. Louis schools is divided into two classes-and the teacher has a copy of the view. This arrangement enables the teacher to take her pupils into the situation which is the topic of the lesson. By discussing every detail in the picture, she makes them thoroughly understand, makes them live, what they discover.

Some time ago the writer heard a lesson on marble quarrying. By means of the picture, of which each pupil had a copy, the children

1 Page 31.

were transported into the mine, as it were, and, under the tactful guidance of the teacher, they found their way into everything the teacher wanted them to learn. In previous lessons the various classes of rocks had been developed, and the order of deposition of the sedimentary rock was studied. The children had brought in samples of sandstone, clay, and marble, and the collection of rocks furnished by the museum had been used to show the limestone in its various degrees of hardness, viz, ooze, coquina, coral, chalk, and marble. After studying the ways in which the rocks were placed in the ground,

a sandstone quarry was visited to observe the method of taking them from the earth. Then the method of quarrying marble was studied by means of a set of stereoscopic pictures, and the following outline used:

Location of quarry.

History of surface as read from picture.

Observation of the details of the picture: Discoloration, stratification, bedding, tunnels, water, pillars, method of drilling-Gadding machine, wedging, channeling machines, derricks.

Comparison with a mine.

Nature's compensations.

The compositions written by the children on the subject of "Marble" showed that they had thoroughly enjoyed their trip to the mine and had received valuable information and training.

The following is a list of the subjects illustrated by sets of 15 stereoscopic views:

Coffee: Coolies picking coffee-Ceylon.

Scouring logs and hauling them into sawmill-Minneapolis.
Stupendous log raft.

Steam shovel loading cars.

Lumber:

Iron:

Marble:

Marble quarry in Vermont.

Coal:

Ladles emptying molten metal into molds.

Cutting peat in the Allen bogs-Ireland.

Miners entering shaft-Illinois.

Digging into the hillside-Pennsylvania.

Seacoasts: Rock and town of Gibraltar.

Volcanoes: Fugiyama's vast, mysterious crater.

Mallibon, strange river of fire-St. Vincent, West Indies.
Crumbling ash deposits-St. Vincent, West Indies.

Erosion: The Sinuous Colorado.

Geysers: "Old Faithful" in action.

Divides: The Continental Divide.