CHAPTERS XX-XXV.

It is not expected that any one scholar can accomplish all that is here outlined. Examples may be selected from the list, as opportunity offers, so that each scholar shall become familiar with several problems.

Few of the problems suggested call for continuous routine observation at fixed hours. They require, on the other hand, an intelligent examination of ordinary weather phenomena, with special reference to discovering their explanation. In most of the problems a small number of observations will suffice. Under the supervision of the teacher, different problems may be a.s.signed to the several members of a cla.s.s; or several scholars may work on different parts of the same problem, exchanging records in order to save time. All the scholars should have a general knowledge of the results which have been obtained from the observations made by the other members of their cla.s.s. The teacher will use his discretion in arranging the order of the problems, and in selecting those that are best suited to the season in which the work is done, to the locality in which the school is situated, and to the facilities and apparatus at command. Although the variety of accessible problems is less in city schools than in country schools, much may be done in the city as well as in the country.

The opportunities for carrying out such observational work vary so much in different schools that it is impossible to give specific instructions, which shall be available in all cases. Some general suggestions are therefore given, which the teacher may supplement by more detailed instructions framed to fit the particular circ.u.mstances of each case.

A review of the headings of the different problems shows that a very general correlation exists among them, whereby the subjects of every heading are a.s.sociated with those of nearly every other. In other words, every weather element is treated as a function of several other elements.

It follows from this that the variety of work here outlined is more apparent than real, and that many problems which appear from their wording to be entirely new are in large part rearrangements of problems previously encountered.

APPENDIX B.

THE EQUIPMENT OF A METEOROLOGICAL LABORATORY.

_A._ INSTRUMENTS.

_Exposed Thermometer_ (United States Weather Bureau pattern), with bra.s.s support, $2.75.

_Maximum and Minimum Thermometers_ (United States Weather Bureau pattern), mounted together on one board, $6.25.

_Wet- and Dry-Bulb Thermometers_ (United States Weather Bureau pattern), mounted on one board, complete with water cup, $6.50.

_Sling Psychrometer_ (designed by Professor C. F. Marvin, of the United States Weather Bureau), consisting of two exposed mercurial thermometers, mounted on an aluminum back, and provided with polished, turned hard-wood handle and bra.s.s tr.i.m.m.i.n.gs, $5.00.

_Sling Psychrometer_, consisting of two cylindrical bulb thermometers, mounted one a little above the other upon a light bra.s.s frame, with a perforated guard to protect the bulbs while swinging, but which can be raised (by sliding upon the frame) for the purpose of moistening the linen covering of the wet bulb. Much less liable to be broken than the Weather Bureau pattern, $5.00.

_Rain Gauge_ (United States Weather Bureau standard), 8 inches in diameter, complete, with measuring stick, $5.25.

_Rain Gauge_, 3 inches in diameter, with overflow and measuring stick, $1.25.

_Wind Vane_ (United States Weather Bureau pattern), $10.00.

_Anemometer_ (United States Weather Bureau pattern), with indicator, aluminum cups, and electrical attachment, $25.00.

The same, with painted bra.s.s cups, $23.00.

_Anemometer Register_ (United States Weather Bureau pattern), with pen and ink attachment, $35.00.

The same, with pencil attachment (old style), $24.00.

_Aneroid Barometer_ (for meteorological work), $14.00-$16.00.

NOTE.--Much cheaper aneroids can be purchased, and may be used to some advantage in the simpler observations in schools.

_Mercurial Barometer_ (Standard United States Weather Bureau pattern), complete with attached thermometer, vernier, etc., $30.00-$33.00.

NOTE.--The above instruments, as used by the United States Weather Bureau, are made by H. J. Green, 1191 Bedford Avenue, Brooklyn, N. Y. The prices are those given in Green's latest catalogue.

_Mercurial Barometer._ New improved form, especially designed for school use. Mounted on mahogany back. Scale engraved on aluminum. Divisions of scale on metric and English systems. No vernier, $5.75.

(L. E. Knott Apparatus Co., 14 Ashburton Place, Boston, Ma.s.s.)

_Thermograph_ (designed by Dr. Daniel Draper, of New York). Consists of a bimetallic thermometer in a case which carries a disk, with a chart upon its axle instead of hands like the ordinary clock. A pen (resting on the face of the disk) registers the fluctuations of temperature as the chart is carried around. Sizes, 14 20 inches, $30.00; 10 14 inches, $15.00.

This instrument may be purchased of H. J. Green.

_Thermograph._ Self-recording thermometer (as adopted by the United States Weather Bureau), made by Richard Freres, of Paris. Records continuously on a sheet of paper wound around a revolving drum, which is driven by clock-work inside. Standard size (without duty), $30.00.

_Barograph._ Self-recording barometer (as adopted by the United States Weather Bureau), made by Richard Freres, of Paris. Similar in general arrangement to the thermograph. Standard size (without duty), $27.60.

These last two instruments can be procured through Glaenzer Freres & Rheinboldt, 26 & 28 Washington Place, New York City.

_Instrument Shelter_ (standard United States Weather Bureau pattern) will hold a set of maximum and minimum thermometers, psychrometer, and a thermograph. May be set up on top of posts driven into the ground, or may be attached to a wall, $18.00.

_Barometer Box_, for the standard mercurial barometer. Made of mahogany, with gla.s.s panels on front and sides; lock and key, and with fittings complete, $8.50.

These may be purchased of H. J. Green.

_B._ TEXT-BOOKS.

_The Story of the Earth's Atmosphere._ DOUGLAS ARCHIBALD. New York, D.

Appleton & Co., 1898. 18mo, pp. 194. 40 cents.

To be recommended to the general reader who wishes to gain some knowledge of meteorology quickly. Not a text-book. Contains a chapter on "Flight in the Atmosphere."

_Elementary Meteorology._ WILLIAM MORRIS DAVIS. Boston, Ginn & Co., 1898.

8vo, pp. 355. $2.50.

The most complete of the modern text-books, and the best adapted for use in the systematic teaching of meteorology. The modern views are presented clearly and without the use of mathematics. Portions of it are somewhat too advanced for school study, but teachers will find it invaluable as a reference book in directing the laboratory work, and in answering the questions of school cla.s.ses.

_A Popular Treatise on the Winds._ WILLIAM FERREL. New York, John Wiley & Sons, 1890. 8vo, pp. 505. $3.40.

This can hardly be regarded as a _popular_ treatise. It embodies, in condensed and chiefly non-mathematical form, the results of Ferrel's researches during his long and profound study of the general circulation and phenomena of the atmosphere. Teachers who advance far into meteorology will find this book indispensable. It is not at all suited for general cla.s.s-room use.

_American Weather._ A. W. GREELY. New York, Dodd, Mead & Co., 1888. 8vo, pp. 286. Out of print, but secondhand copies are probably obtainable.

Deals, as the t.i.tle implies, especially with the weather phenomena of the United States. Contains brief accounts of individual hot and cold waves, hurricanes, blizzards and tornadoes, and gives specific data concerning maxima and minima of temperature, precipitation, etc., in the United States.

_Meteorology: Practical and Applied._ JOHN WILLIAM MOORE. London, F. J.

Rebman, 1894. 8vo, pp. 445. 8 shillings.

A readable book. Considerable s.p.a.ce is given to instrumental meteorology.

Contains chapters on the climate of the British Isles and on the relations of weather and disease in the British Isles. Especially adapted for the use of English readers.