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QUERY

TO THE READERS OF SCIENCE.

.

D.C.

Can any

reader of Science cite a case of lightning stroke in

PUBLISHER'S ANNOUNCEMENT. which the dissipation of a small Titles of Some Articles Published in Science since | Baur, G., Clark University, Worcester, Mass.

, J., Agricultural . conductor (one-sixteenth of an

Jan. 1, 1892.

Beals, A. H., Milledgeville, Ga.
Beauchamp, W. M.,

Baldwinsville, N.Y.
Aboriginal North American Tel.

Boas, Franz, Clark University, Worcester, Mass. inch in diameter, say,) has failed Actinism.

Bolley, H. L., Fargo, No. Dak.
Agriculture, Experimental, Status of.

Bostwich, Arthur E., Montclair, NJ. to protect between two horizon- Anatomyano 1oaching of, to Advanced: Medical Brinton, D. G., Philadelphia, Pe. Amenbotep, , the of.

Bradley, Milton, Springfield, Mass.
Students.

Des &. tal planes passing through its Anthropology. Current Notes on.

,

Chandler, H., Buffalo, N.Y.
Architectural Exhibition in Brooklyn.

Comstock, Theo. B., Tucson, Arizona.
Arsenical Poisoning from Domestic Fabrics.
upper and lower ends respective. Artesian Wolis in lowa.

Conu, H. W , Middletown, Conn.
Cragin, F. W., Colorado Springs, Col.

Davis, W. M., Harvard College, Cambridge, Mass. ly? Plenty of cases have been Bacteria, Some Uses of.

,

Dimmock, George, Canobie Lake, N.H.
Botanical Laboratory, A.

Farrington, E. E., Agricultural Station, Champaigo,
Brain, A Few Characteristics of the Avian.

Ill. found which show that when the Bythoscopidæ and Cereopida.

Ferree, Barr, New York City.
Canada, Royal Society of.

Flexner, Simon, Johns Hopkins University, Balticonductor is dissipated the build-Chalicotherium, The Ancestry of.

more, Md.
Chemical Laboratory of the Case School of Applied Gallaudot, E. M., Kendall Green, Washington, D.C.

Foshay, P. Max, Rochester, N.Y. ing is not injured to the extent Science.

Garman, S., Museum of Comp. Zool., Cambridge,
Children, Growth of.

Mass.
Collection of Objects Used in Worship.
explained (for many of these see Corneli, Tho change at.

Golden, Katherine E., Agricultural College, Lafay

ette, Ind,
Deaf, Higher Education of the.
.

Hale, Edwin M., Chicago, Ill. volumes of Philosophical Trans. Blectrical Enginoor, Tho Technical Education of.

Hale, George S., Boston, Mass.
Eskimo Throwing Suicks.

Hale, Horatio, Clinton, Ontario, Canada.

Hall, T. Proctor, Clark University, Worcester, Mass. actions at the time when light. Etymology of two Iroquolan Compound Stems. Halsted, Byron D., Rutgers College, New Bruns

-Habits.

wick, ning was attracting the attention Bach e la pressione Motor Muscles of, to Certain Haworth, Erasmus, Oskaloosa, Iowa.

Facial

Hay, 0. P., Irvington, Ind.
Family Tralts, Persistency of.

Haynes, Henry W., Boston Mass. of the Royal Society), but not Floos

: The Distribution of.

Hazen, H. A., Weather Bureau, Washington, D.C.
Fossils, Notice of .
Four-fold Space, Possibility of a Realization of.

Hewitt, J. N. 'B., Bureau of Ethnology, Washington,

D.C. an exception is yet known, al. Gems, Artificial Detection of. Glacial Phenomena in Northeastern New York.

Hicks, L. E., Lincoln, Neb.

Hill, E. J., Chicago, Ill. though this query has been pub. Great Lakes, origin of tho Basins ol. Grasses, Homoptera to.

Hill, Geo. A., Naval Observatory, Washington, D.C. of

Hitchcock, Romyn, Washington, D.C. “ Healing, Divine.”

Holmes, E. L. Chicago, Ill. lished far and wide among elec- Hemipteri us Mouth, Structure of tho.

Hotchkiss, Jed., Staunton, Va.
Hofmann, August
elm von.

Howe, Jas. Lewis, Louisville, Ky.
tricians.
Hypnotism among the Lower Animals.

Hubbard, Gardiner G., Washington, D.C.
Hypnotism, Traumatic.

Jackson, Dugald C., Madison, Wisconsin
Indian occupation of Now York.

James, Joseph F., Agricultural Dept., Washington,
First inserted June 19, 1891. No re- Influenza, Latest Detalls Concerning tho Germs of.

Jobuson, Roger B., Miami Univorsity, Oxford, O.
Insects in Popular Dread in New Mexico.
sponse to date.
Inventions in Foreign countries, How to Protect.

Kellerman, Mrs. W. A., Columbus, O.

Kellicott, D. S., State University, Columbus, O.
Inventors and Manufacturers, the American Associ.

Kellogg, D. S., Plattsburgh, N. Y.
ation of.
N. D. C. HODGES,

Lintner, J. A., Albany, N. Y.
Iowa Acadomy of Sciences.
Jargon, The Chinook.

Loeb, Morris, New York City.

Mabery, Charles F., Cleveland, Ohio.
Jasside; Notes on Local.
874 BROADWAY, NEW YORK.

Macloskie, G., Princeton, N.J.
Keller, Helen.
Klamath Nation, Linguistics.

McCarthy, Gerald, Agricultural Station, Raleigh,

N.C.
Laboratory Training, Alms of.
Lewis H. Carvill, Work on the Glacial Phenomena,

MacDonald, Arthur, Washington, D.C:
THE RADIOMETER. Lightning, The New Method of Protocting Buildings Mason, O. T., Smithsonian Institution, Washington,

Marshall, D. T., Metuchen, N.J.
Lissajou's Curves, Simple Apparatus for the Produc- Mill-paugh, Charles F., Morgantown, W. VA.

D.C.
By DANIEL S. TROY.

Nichols, C. F., Boston, Mass.
Maize Plant, Observations on the Growth and Chemi.
This contains a discussion of the reasons
cal Composition of.

Nuttall, George H. F., Johns Hopkins University, for their action and of the phenomena pre- Maya Codices, a Key to the Mystery of.

Baltimore, Md.

Oliver, J. E., Cornell University, Ithaca, N.Y. sented in Crookes' tubes.

Medicine, Preparation for the Study of.
Mineral Discoveries, Some Recent, in the State of Osborn, Henry F., Columbia College, New York

City.
Price, postpaid, 50 cents.
Washington.

Osborn, Herbert, Agricultural College, Ames, Iowa.
Museums, The Support of.

Pammel, L. H., Agricultural Station, Ames, Iowa.
N. D. C. HODGES, 874 Broadway, N. Y.

Palopquo Tablet, a Brief Study of.
Patent omce Building, Tho.

Pillsbury, J. H., Smith College, Northampton, Mass.

Poteat, W. L., Wake Forest, N. c.
Physa Heterostropha Lay, Notes on the Fertility of.
Pocket Gopher, Attempted Extermination of.

Preble, Jr., W. P., New York City.
THE BOTANICAL GAZETTE.

Ruffner, W. H., Lexington, Va.
Polariscopes, Direct Reflecting.

Sanford, Edmund C., Clark University, Worcester,
Psychological Laboratory in the University of To

Mass.
A monthly illustrated journal of botany in

Schufeldt, R. W., Washington, D.C.
all its departments.
Psychological Training, The Need of.

Scripture, E. W., Clark University, Worcester, Mass.
Psylla, the Pear-Tree.

Slade, D.' D., Museum Comp. Zool., Cambridge,
25 cents a number, $2.50 a year.
Rain-Making.

Mass.
Rivers, Evolution of the Loup, in Nebraska.
Address

Smith, John B., Rutgers College, New Brunswick,
PUBLISHERS BOTANICAL GAZETTE, Sestrurus and Crotalophorus.
Scientific

N.J.

Southwick, Edmund B., New York City.
Bloomington, Ind.

Star Photography, Notes on.
Star, The Now, in Auriga.

Stevens, George T., New York City.

Stevenson, S. Y., Philadelphia, Pa,
Storage of Storm-Waters on the Great Plains.

Stone, G. H., Colorado Springs, Col.
JOHN IRELAND'S Bookstore, 1197 Broadway Teaching of Science.
Tiger, A New Sabre-Toothed, from Kansas.

Thomas, Cyrus, Washington, D, C. near 20th St., is convenient to the residence quarter of Timber Trees of West Virginia.

Thurston, R. H., Cornell University, Ithaca, N.Y. the city; it is a good place to drop into on the way up

Todd, J. E., Tabor, IOWA. Trachew of Insects, Structure of. or down town to select books or stationery.

True, Frederick W., National Museum, Washing. VoinFormation, Valuablo Experiments in. is well selected and embraces all the new and standard books as soon as issued. Out-of-town purchasers can Weeds as Fertilizing Material,

Turner, C. H., Univers of Cincinnati, Cincinnati, order by mail with every confidence that their wants Will, a Recent Analysis of.

0.
will be as well supplied as if buying in person.
Wind-Storms and Trees.

Wake, C., Staniland, Chicago, Ill.
Wines, The Sophisticated French.
AUTHORS AND PUBLISHERS.

Zoology in the Public Schools of Washington, D. c. Ward, R. Dec., Harvard University, Cambridge,
Material arranged and compiled for all kinds of

from.

tion of.

ronto.

His stock

ton, D.C.

Ward, Stanley M., Scranton, Pa. works, excepting fiction. Statistics a specialty. Some of the Contributors to Science Since Jan. Warder, Robert B., Howard University, WashingIndexing and cataloguing. Address G. E. BIVER, 835 N. 10th Street, Philadelphia.

I, 1892.

Welch, Wm. H., Johns Hopkins University, Balti

more, M.D. Aaron, Eugene M., Philadelphia, Pa.

West, Gerald M., Clark University, Worcester, Mass. ACK NUMBERS and complete sets of leading Mag. Allen, Harrison, Philadelphia, Pa.

Whitman, C. O., Clark University, Worcester, Mass. BA

Rates low. AM, MAG. EXCHANGĒ, Baldwin, J. Mark, University of Toronto, Canada. Willams, Edward A., Lehigh University, BethleSchoharie NY Barnes, Charles Reid, Madison, Wis.

hem, Pa.

Mass.

azines.

HA

SEP 12

LIBRARY

SCIENCE

A WEEKLY NEWSPAPER OF ALL THE ARTS AND SCIENCES.

PUBLISHED BY N. D. C. HODGES, 874 BROADWAY, NEW YORK.

TENTH YEAR. VOL. XX. No. 501.

C' SEPTEMBER 9, 1892.

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SINGLE COPIES, TEN CENTS. $3.50 PER YEAR, IN ADVANCE.

CONTENTS.

INSECTS AND INSECTICIDES. New

The Lightning Dispeller.

XIV.

Protecting Property A PRACTICAL MANUAL,

from ightning THE IMPURITY OF ICE. Charles Platt.......... 141

Concerning Noxious Insects and the Methods
ELEMENTARY SCIENCE IN THE PUBLIC SCHOOLS.
Henry Montgomery

142

of Preventing their Injuries. NOTES AND NEWS....

145

By CLARENCE M. WEED,
THE AMERICAN ASSOCIATION AT ROCHESTER,
D. S. Martin.....
146 Professor of Entomology and Zoology, New

Price, $20 to $30.--According to size.
AMERICAN BOTANISTS AND NOMENCLATURE. John
M. Coulter....

146
Hampshire State College.

The Patent Lightning Dispeller is a conduc-
CURRENT NOTES ON ANTHROPOLOGY.
Daniel G. Brinton, Editor..
147

tor specially designed to dissipate the energy

WHAT IS SAID ABOUT IT. LETTERS TO THE EDITOR.

“I think that you have gotten together a very

of a lightning discharge, -to prevent its A Pre-Aino Race in Japan. Edward S. useful and valuable little book."- Dr. C. V. Riley, doing harm,-placing something in its path Morse....

148 U.S. Entomologist, Washington, D. C. On the Fundamental Hypotbeses of Abstract

"It is excellent." --James Fletcher, Dominion En upon which its capacity for causing damage Dynamics. Edward T. Dixon..

149 tomologist, Ottawa, Canada. J. G. MacGregor...

150 I am well pleased with it.”—Dr. F. M. Hexamer, may be expended.
Editor American Agriculturist, New York.

No recorded case of lightning stroke has The Nomenclature Question. G. H. French, 151

• It seems to me a good selection of the matter The Grand-Gull Formation. Laurence C. which every farmer and fruit grower ought to have yet been cited against the principle of the Johnson..

151

at his immediate command." --Prof. $. A. Forbes, Dispeller. So far as known, the dissipation European Origin of the Aryans. Isaac

State Entomologist of Illinois, Champaign, Ill.

"A good book, and it is needed."-Prof. L. H. of a conductor has invariably protected under Taylor.

Bailey, Cornell University.
Acid Prevention of Cholera. S. V. Clevenger. 151 " It is one of the best books of the kind I have the conditions employed.
Mars. C. W. Kempton

152

ever seen."-J. Freemont Hickman, Agriculturist, La Grippe. M. L. Holbrook. Ohio Experiment Station, Columbus, Ohio.

Correspondence solicited. 152

“I shall gladly recommend it."- Prof. A. J. Cook, BOOK REVIEWS. Michigan Agricultural College.

AGENTS WANTED. Journal of American Ethnology and Archæ

Price, $1.25. ology.

Sent postpaid to any address on receipt of price. The American Lightning Protection Company, Entered at the Post-Office of New York, N.Y., as

N. D. C. HODGES, 874 Broadway, New York.
Second-Class Mail Matter.

United Bank Building, Sioux City, lowa.

151

152

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NEW YORK, SEPTEMBER 9, 1892.

THE IMPURITY OF ICE.

BY CHARLES PLATT.

WHEN we consider the large quantities of ice used annually in the United States, especially during the summer months, when drinking-water without ice is indeed a rarity, it seems strange that the purity of the ice should so seldom be questioned. On the contrary, while many people will exercise the greatest caution regarding their drinking-water, the origin or source of their icesupply troubles them not at all. The ice-man brings it, and there is no further need of investigation. This feeling of danger on the one hand, and perfect security on the other, have been, without doubt, due to tbat peculiar science, “popular chemistry,” so widely disseminated in various publications of the land, and especially in the newspapers of the smaller towns with their “patent imsides” bristling with various startling items, often of scientific import.

That this theory, once so popular, of the purification of water by freezing is not in accordance with facts is hardly worth demonstration; we will simply state that while water in its crystalline state should theoretically be nearly pure, still, owing to its peculiar formation in needle-like crystals, considerable foreign matter present in the water in suspension may be, and is, mechanically held within the mass.

On the other hand, of late years there has been a revulsion of public sentiment, and statements have been made denying that water is purified at all by its crystallization. Others have gone so far as to say that certain bacteria thrive best at this low temperature, and, whilst they may be harmlessly disseminated through the water, in the ice they have become concentrated and doubly active. This certainly cannot be sustained by any known facts regarding bacteriological growth, and yet may have some foundation in the fact that in the freezing of still water, such as that of a pond, or small lake, there is a certain concentration of some species of bacteria at the surface of the water, and thus the first inch of ice may contain these in increased numbers as compared with a sample of water from the same lake. As to the increased activity, or indeed as to any vital activity at all of these bacteria, this is another question, and yet to be proven. When this ice is melted, however, and the temperature of the resultant water is raised maybe to the full heat of a summer's day or to that of an over-heated roon, then we have another problem, that of possible decomposition and organic change in these organisms that may induce results equal to and exceeding those of the bacteria themselves.

We do not mean to say that all bacteria are necessarily killed outright by the freezing of the water, — the contrary has been proven in many cases, and notably by Dr. Prudden in bis wellknown experiments with the germs of typhoid fever, – but, in this as in other cases, the germs were found to be present always in decreasing numbers, and in longer or shorter time their vitality is lost altogether. Disease has undoubtedly been produced by use of ice from polluted sources, and this, too, when mere analysis of the ice in comparison with water standards would by no means condemn it. But here let us state that we can by no means use water standards in the analysis of ice. The standards must be much higher, and the analysis must needs be conducted with great care in order to arrive at correct results, even in cases where the ice may be in a manner contaminated.

In regard to the preparation of samples for analysis, Wm. R. Nichols, in his admirable work on “Water Supply,” gives a few

simple directions that every chemist will do well to follow. “In melting ice for analysis, a fair specimen cake should be selected and broken into fragments in a clean place. The fragments may then be placed in a wide-mouthed bottle covered with a plate of glass, and when enough of the ice has melted to have washed itself, this portion of the water is poured away and the remainder, after melting, subjected to analysis.” The same author points out the danger of exposing the melting ice to the air, owing to its liability to attract organisms from the air itself, thus vitiating entirely the results of the analysis.

In the year 1888, the State Board of Health of Massachusetts was directed “to make a special investigation with reference to the pollution of ponds, lakes, streams, and other bodies of water used as ice supplies" in that State. The results of this investigation, which was admirably conducted, are of extreme value; as, by the systematic methods adopted, they were enabled to secure considerable data of general and vital interest to the public as well as to the chemist. Fifty-eight sources of supply were examined, their chemist making, in all, analyses of seventy-six samples of water and two hundred and thirty-six samples of ice. The deductions drawn from their work, stated as concisely as possible, are as follows: In the formation of the ice the color and saline matter of the water is completely removed, and also all but 13 per cent of the other impurities. The same cake of ice will vary greatly as to quality in different parts. The substances in solution are excluded from the ice in much larger proportion than are those in suspension. Of the different kinds of ice, classified as snow ice, bubbly ice, and clear ice, the two former contain a far greater percentage of impurity than the latter, while the upper third of the cake in all cases carries a higher percentage of impurity than the lower two-thirds.

Snow falling upon thin ice will cause it to sink, and finally the snow will become saturated with water; which, in turn freezing, includes within the mass all of its impurities. Then, too, the falling snow has already collected from the air such impurities as were contained, and those also are to be found in the resultant snow ice. The flooding of an ice-field by cutting holes and allowing the water to spread over the ice surface, there to freeze, gives a layer of ice of equal impurity with the water itself; and yet this inethod of rapidly building up the ice-crop is practised to a great extent throughout the country.

That the bacteria are largely to be found in the surface and snow ice can be seen by the following figures, arrived at by the above mentioned Board of Health. In snow ice was found 81 per cent as much bacteria as in the water itself. The ice as a whole contained but 10 per cent, and the clear ice but 2 per cent. The average results of all the analyses made by the Board of Health show that the total organic impurities of snow ice amount to 69 per cent of those of the water, and the organic impurities of all the ice except snow ice 12 per cent, while the clear ice contains but 6 per cent. The color was entirely removed and the saline matter nearly so.

As mentioned above, the impurity of the snow ice is not due to the water alone, but the air as well must be looked to to account partly for this great increase of organic matter.

These figures might tend to give one a feeling of great security in using ice, as at first thought the decrease of organic matter in clear ice from that originally present in the water itself would seem to argue perfect safety in using ice from any ordinary supply.

The Massachusetts Board of Health, however, carefully point out that it is not the number of bacteria alone that is to be considered, but their kind, and they insist that no water-supply that is not fit for drinking purposes should for any reason be used as a supply for ice; and yet how often is this the case; stagnant ponds and even sluggish canals receiving their drainage from

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many sources being all thought fit to yield their share of the ice scribing the kind of material suited to his condition, and the barvest.

character of the methods of instruction to be employed in his Fortunately of late years, owing to the repeated failure of the particular case. ice-crop, the larger cities in the east are mainly supplied with To the question, Should science be taught in the public or “artificial” ice. This ice, being formed as it is in the greater num- common schools ? I answer in the affirmative. Most decidedly, ber of cases from the regular water-supply of the city, ceases to a yes.

Which of the sciences ? Should it be chemistry, or physics, large degree to be a source of danger from organic contamination. or zoölogy, or mineralogy, or botany, or physiology, or geology ? There have been cases, however, and notably one which fell under I answer, all of them as one subject, the study of nature. Spemy own observation, wbere an ice company, advertising their ice as cialization, differentiation, or the division of labor, characterizes made only from pure distilled water, produced daily for some weeks civilization. It is forced upon us in the higher studies. This is beautiful cakes of crystalline ice, the centre of each cake a rich, simply a matter of necessity, due to the vastness of the fields of dark brown, and actually giving forth an offensive odor! Some higher learning, the shortness of life, and the limits of tbe human of these samples were sent to me for analysis, and the results were mind. But, it is possible to specialize only in the maturity of most startling, indicating rather a concentration of impurity, both manhood and womanhood. It is not possible in childhood. The organic and inorganic, than a distillation or purification. The

youthful mind is not capable of such work. The young mind is cause was naturally looked for and found in the stills themselves, not able to fix attention or concentrate thought upon a subject, which were eventually overhauled and remodeled, with the result and particularly if the subject be studied in an isolated and that finally a first-class high-grade ice was put on the market. disconnected manner. Add to this a method that is both system

The necessity for an absolutely wholesome water-supply for the atic and abstract and the avenues to learning are completely manufacture of ice is at once apparent, as in processes generally closed. In very early years, say before the age of eleven or in use the entire contents of the water tanks are frozen, and all twelve, the average child cannot readily or profitably study impurities contained in the water must needs enter the ice. The

anything in an isolated, a systematic, and an abstract manner, case referred to was interesting, showing as it did how the color and he can do it but very feebly at this age. The study of a and organic matter had been concentrated in the middle of each subject systematically by classification, the study of the abstract, cake, The ice forming first at the sides bad repelled these im- and the cultivation of the reasoning faculty should not be atpurities until finally, with the freezing of the entire mass, they tempted early. Nature rebels against it. It is the faculty of perhad of necessity been included.

ception which appears first. This is the faculty which should

receive the attention of the teacher of children. To the cultiva. ELEMENTARY SCIENCE IN THE PUBLIC SCHOOLS.

tion of observation, expression, and memory, along with the full

physical development of the child, all the best energies of the BY HENRY MONTGOMERY, PROFESSOR OF MINERALOGY AND GEOLOGY

teacher should be given. It is not a question, then, of dividing and IN THE UNIVERSITY OF UTAH, SALT LAKE CITY.

classifying the natural and physical sciences, and choosing one or MANY years' continuous service as a teacher of young men and more of them to be placed on the curriculum of schools. This is women, in a measure, unfits one for acting as an instructor of necessary and proper in the later years of the high-school courses, children. I do not say that a teacher of children requires greater and in the higher institutions, but not in the common school, or or higher qualifications than a teacher of college students; but to any great extent in the lower classes of the high school. Systhe qualifications must be different. One who aspires to be a tem, method, and classification in study åre exceedingly importeacher and leader of students of advanced subjects as taught in tant for matured persons; but, they do not belong to early life. colleges and universities ought to have good mental faculties, and As soon as the mind is prepared to undertake such work, it these ought to be in a high state of cultivation. With the in- should be begun; and it should be increased very slowly, graducreasing intricacy and complexity of the studies come increasing ally, and almost imperceptibly. I repeat it, common-school pudifficulties for the students. These difficulties must be recognized pils ought not to be taught zoology as a distinct science, nor and dealt with by the instructor. Hence the successful univer- botany, nor pbysics, nor geology as such. All systems of classity teacher must be possessed of teaching powers suited to the sification, even to the division of these sciences, are artificial. minds of students of the advanced branches in which he under- Chemistry, physics, mineralogy, botany, zoology, physiology, takes instruction. Both the character of the studies and the men. and geology should not be separated. These sciences come naturtal condition of the students of the university differ widely from ally together; and, therefore, they are most readily understood those of the pupils of the common school. Consequently the and remembered when studied in this way. Let the child see the teachers of these two classes of pupils must differ widely as to fish swim in the water, the bird fly through the air, the duck qualifications. Between the primary or common school, on the swim and sail on the pond, the river erode its banks, the waves one hand, and the university, on the other, comes the secondary or beat and grind the pebbles against one another on the beach. high school, which, of necessity, must be supplied with teachers Let him be led to use his senses in observing the soil, clay, sand, of somewhat different qualifications. The high-school teachers gravel, grasses, trees, flowers, butterflies, beetles, worms, crops, must be adapted to the work of instructing pupils of certain streams, hills, ravines, bees, squirrels, ants, crickets, birds, snow, attainments and generally of a certain average age, which stand rain, stones, rocks, and fossils, just as they occur in nature. In between the common school and the university. A still more any case, even to adult persons, the associations are of vital sigsatisfactory grading is effected by classifying all pupils in five pificance. Many a time it happens that a mineral sample, a bit divisions, viz., the kindergarten, the common school, the high of rock, or a fossil, by itself is of but little use in helping us to school, the college, and the university; and in these, especially in upderstand some question of moment. Again, an extract from a the common school, a further grading often proves beneficial. It book may be unintelligible or ambiguous. But, in the one inhas many times been found that one who has succeeded well stance, permit us to see the associated minerals and rocks in positeaching a class in some branch in the common school, has not tion, and, in the other, to read the context, and what a flood of succeeded as a teacher of a lower class or a bigher class in the light is let in upon us! The relations that objects of the three same branch and in the same school. We all know that a child kingdoms of nature bear towards one another are of the utmost will voluntarily leave other children that may be older or younger importance. But, in addition to the importance of the associathan himself, and seek out those of his own age, or, rather, of his tions and relations, the ease with which children are enabled to own mental attainments; and, again, on reading a story to a child comprebend the characteristic structure, habits, and uses of anyof nine years no interest is awakened, while on reading tbe same thing when studied as it occurs in nature, is something the to another two or three years older or younger the most lively in- teacher and parent cannot afford to ignore. An old-fashioned terest and appreciation of it are immediately manifested. The method of teaching orthography consisted in compelling the first thing, then, to be considered in the teaching of science is pupil to learn a column or a page of isolated words chosen with the stage of the development of the faculties of the child. Let reference to the number of syllables they contained. Some of this be first diagnosed, and then let no mistake be made in pre- these words were extremely rare; many of them would not be

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