A half-dozen, or dozen, males chase down a female, roll her in the dust or mud, as the case may be, and, despite the frantic fighting back, pull her tail, peck her wings, pinch her with their claws, and when the tormenters are tired out, and she panting with exhaustion, the whole party adjourn to a convenient heap of dung, and, in less time than it is spoken, the joke seems forgotten.

They drive away birds larger and more courageous than themselves, if they are perching birds, by following at their heels, and doubtless also making uncomplimentary remarks. Watch the arrival of the first robin, and see the three or four hoodlums follow him from tree to tree for the first week after his coming. dares touch him, but they make his life miserable.

Not one

The song sparrow, though he will vanquish the Englishman every time, soon tires of being tagged from bush to tree, and leaves in disgust. The same is true of the catbird, and to some extent of the oriole, which is also less common by half. I have seen them pull a "chippy's" nest to pieces during the owner's absence out of pure mischief, and I presume they do the same to the nests of other birds.

It is difficult to see what there is to recommend the little villain, and the man who introduced him should be classed with the man who introduced rabbits into Australia.

Fort Edward, Aug. 22.

Celestial Photomicrography.

X.

STELLAR photography has advanced enough to justify the hope that, by the next opposition of Mars, some means of scrutinizing his landscape more closely may be found. If microphotography and its associated science, photomicrography, are pushed on parallel lines with stellar photography by co-operating specialists who can appreciate the requirements in both fields, something valuable may result.

The possibility of an Atlantic cable was laughed at by good electricians, and astronomers despair of overcoming the difficulties presented by diffraction, irradiation, chromatic and atmospheric blurrings, and light absorption; but these matters have been conquered in many respects in telescopy and general photography.

Materials that will afford the densest homogeneity of surface should be sought for, upon which the photographs can be taken, to be later scrutinized with microscopic lenses. It may be possible to arrange a battery of microscopes to take enlarged cameralucida photographs, which in turn may be enlarged by "solar prints;" and if surfaces can be invented or discovered smooth and continuous enough to admit of these successive enlargements without breaking up the details, we may possibly capture the Martial men in the act of filling Schiaparelli's canals, and otherwise observe what their estimated five million years of seniority over us affords them. S. V. CLEVENGER.

Chicago, Aug. 21.

As to the "Extinction" of the American Horse. IN 1881, in the Kansas City Review, E. L. Berthoud pointed out the fact that, in maps drawn up by Sebastian Cabot (who went in 1527 to the east coast of South America) to show his discoveries, at the head of La Plata, with figures of other animals he gives that of the horse.

This fact, as thus put on such indubitable record, is accepted by scientists, including Heilprin, Wilckins, and Flower. The latter, in his manual on "The Horse "(1891), says: "The usual statement as to the complete extinction of the horse in America is thus qualified, as there is a possibility of the animals having still existed, in a wild state, in some parts of the continent remote from that which was first visited by the Spaniards, where they were certainly unknown. It has been suggested that the horses which were found by Cabot in La Plata in 1530 cannot have been introduced."

The above is surely of great interest, and is worthy of repetition. The writer has come across two statements, which, taken in connection with the above, appear to be even more important and

significant, and may profitably be given wider prominence. As they are not generally known, they are given for the purpose of their receiving the attention that they seem to deserve.

In the volume of the Naturalist's Library, entitled "The Horse," by Major Hamilton-Smith, published in London in 1841, appears the following: "Several recent travellers in the northern portion of that continent [America] question the race of horses now so abundant being imported subsequent to the discovery by Columbus" (p. 147).

In "The History and Delineation of the Horse," by the noted authority, John Lawrence, published in London, 1809, the following sentence occurs: The non-existence of the horse in America, previous to its discovery by Europeans, has, however, been disputed; but I recollect not by whom, or upon what ground” (p. 7). ROBT. C. AULD.

Some Notes on The Rochester Meeting.

WHERE did the scientists come from? The first four hundred names on the register show their geographical distribution as follows, by States: New York, 119; Washington, D. C.. 44; Ohio, 35; Pennsylvania, 24; Massachusetts. 22; Indiana, 19; Illinois, 18; Canada, 17; Connecticut, 13; Michigan, 11; Wisconsin, 10; Iowa, 10; New Jersey, 9; Missouri, 7; Maryland, 4; Kentucky, 4; Tennessee, 4; Alabama, 4; Maine, 3; Vermont, 3; California, 3; New Hampshire, Rhode Island, Minnesota, Georgia, and Florida, each 2; Virginia, West Virginia, North Carolina, Mississippi, Louisiana, and Texas, each 1.

More than one-fourth of the whole number came from New York State. Of the 119 from the State, 32 were from New York City and Brooklyn, 24 from Rochester, and 18 from Ithaca. Washington, D. C., furnished 44, the largest number from any one city. The whole of New England sent oaly 45, although it has until recently been considered the scientific headquarters of the country, and is more thickly dotted with colleges than any other section. Cornell University was more largely represented than any other University, while Princeton was not represented at all; the New Jersey delegation coming ehiefly from Rutgers and Stevens. The central western States showed up handsomely, and twelve southern States sent from one to four men each; while from the States and Territories west of the Missouri River there was no representation at all, except three from California.

Geographically, therefore, the scientists who attended the meeting are not evenly distributed. New York State sent far more than its quota, even after deducting the attendance from Rochester, the place of meeting. In proportion to its population, Ohio sent twice as many as Pennsylvania, although its average distance from Rochester is greater.

The programme for the third day of the meeting (Friday) contained a list of 146 members that had been elected since the Washington meeting, with symbols expressing their affiliations with the different sections. The majority of these new members specified their intention of joining one section only, but many named two sections, and some three. Twelve members did not specify any section. The following shows the apportionment of these new members among the sections:

plied sciences, chemistry, physics, and mechanical science, put together. Geology, geography, biology, and anthropology furnish more than half of all the new members.

In the reading of papers before the sections, the same want of proportion was shown. Section F, biology, held sessions on both Thursday and Friday, morning and afternoon; and 32 papers were listed for those two days. Section I, economic science and statistics, held a session on Thursday afternoon only, and none on Friday, and only 4 papers were listed, and of these the only paper that was statistical was a five minute paper on Statistics of the Salvation Army! The Section of Biology, in fact, is so overcrowded with papers and discussions that it was decided to split it into two sections, F, Zoology, and G, Botany; while a proposition was made, although not entertained, to consolidate sections D and I into one section.

At the recent meeting of the British Association, it is reported that there were 2,500 members in attendance. At the Rochester meeting there were less than 500.

From the above facts, it appears that the American Association is not a fairly representative body of American scientific men. In it the physical sciences are dwarfed by the natural sciences. The reason for this is undoubtedly because the applied scientists, and especially those in the department of mechanical science, have so many societies of their own that they are diverted from and lose their interest in the American Association. In engineering there are four large national societies, the civil, the mechanical, the mining, and the electrical, besides numerous local societies, aggregating a membership of probably 5,000 persons, not counting duplications of those who belong to two or more societies. The small attendance at the section of economic science is probably due to the superior attractions offered by the American Social Science Association. The recent reorganization of the American Chemical Society with its branches will be very apt to diminish the interest of chemists in section C.

These facts are worthy of consideration by those interested in the future of the Association. WILLIAM KENT.

New York, Aug. 29.

BOOK-REVIEWS.

Report of the United States Board on Geographic Names. Ex. Doc. No. 16, House of Representatives, 52d Congress. Washington, Government.

THE necessity of bringing about a uniform usage and spelling of geographic names throughout the executive departments of the government has led to the creation of a board representing the Departments of State, War, Treasury, Navy, and Post Office, the Coast and Geodetic Survey, the Geological Survey, and the Smithsonian Institution, who serve without pay and can officially say in many cases what names shall be used. Names in our country have not been bestowed by any formal authority, except the more important ones of States, counties, and municipalities. The early explorers would employ aboriginal designations or others of little import; their successors often proposed others; a mountain range would receive different names from different sides of approach. Post-offices and railroad stations may not conform to the local names of the enclosing townships, or else very familiar terms have been excessively multiplied. The modes of spelling vary from time to time. To meet the various necessities, the Board adopted the following rules in case the local usage is divided: 1, Avoidance of the possessive form of names; 2, the dropping of the final "h" in the termination burgh;" 3, the abbreviation of “borough" is "boro:" 4, the Websterian spelling of "center;" 5, the discontinuance of hyphens in connecting parts of names; 6, the omission, whenever practicable, of the letters "C. H." (court house) after the names of county seats; 7, the simplification of names consisting of more than one word by their combination into one word; 8, the avoidance of the use of diacritic characters; 9, the dropping of the words"city" and "town" as parts of names.

66

As to the employment of foreign words, the Board recommend that our charts for the use of the navy adopt the local names in

the language of the several countries, and for home use the Anglicised forms. About 2.000 names have already been passed upon, of which a list is printed as an appendix to the report. Another appendix presents a list of all the counties in the United States. It is easy to see that this Board is doing great service for the improvement of geographic nomenclature. Unfortunately, it cannot have power to compel the adoption of the sensible names proposed for the new States recently added to our galaxy and rejected by Congress, nor can it persuade people to use good sense after controversies have been inaugurated. The world is, however, improving, and the very objectionable names are everywhere ridiculed.

The Naturalist in La Plata. By W. H. HUDSON. London, Chapman & Hall. Ill. 396 p.

THE universal interest now taken by all classes in scientific matters has of late years given rise to a new class of books of travel. The celebrated “Voyage of a Naturalist," by Darwin, or perhaps more properly the "Wanderings in South America," by Waterton, formed the starting-point for a series which includes such books as "Travels in Peru," by von Tschudi; "Travels on the Amazon" and "Malay Archipelago," by Wallace; "Naturalist on the Amazons," by Bates; "Naturalist in Nicaragua,” by Belt; "Two Years in the Jungle," by Hornaday; "Life in the East Indies," by Forbes, and many others of similar title and character. The existence and popularity of these books is evidence of the interest they have excited in the public mind; and in view of the good influence they exert there cannot be too many of them. The "Natural History of Selborne," although limited in its scope to a single parish in England, is an example of the multitude of objects which can be made interesting to all classes of readers, and it is perhaps not too much to say that there is scarcely a section of our own country about which an equally interesting book could not be written. The fact is that the objects to be studied in nature are inexhaustible. They exist in earth, in sky; in air, in water; in lane, in tree, in barren plain. Everywhere in fact that one can turn, facts of the profoundest interest are to be observed.

The ordinary globe-trotter has left few places unexplored as far as his foot alone is concerned. He has penetrated to the wilds of tropical Africa, and has left his traces amid the snow and ice of the Arctic regions; he has suffered from hunger and thirst in the deserts of Australia, and has been shipwrecked in the vast Pacific; he has explored the snowy heights of the Himalayas and the Andes, and penetrated the humid jungles of India; he has braved the sands of the desert of Gobi and the terrible glare of the Sahara. The globe-trotter used to write books describing his travels; but, alas, too frequently his eyes saw no further than his feet. He chronicled his daily aches and ills, his breakfast and supper, and mentioned the rivers he crossed or the mountains be The day for such books has passed; and a man who would be listened to now must have more to tell of than how he cooked bis dinner, of how many miles he sailed or walked or rode. The modern traveller must, therefore, be versed in some branch of science. He must know men, or birds, or beasts, or plants. volume, too, must be something more than a mere itinerary; and the more closely he studies the workings of nature in her secluded haunts the wider the circle of his readers and the greater the value of bis book.

saw.

His

Of such books as those we have mentioned above there cannot be too many. It is, therefore, with a feeling of pleasure that we welcome a late comer to the ranks, "The Naturalist in La Plata." The author is a native of the country whose phases of life he chronicles. He is an enthusiast, a lover of beasts and birds, and he makes his reader love with him. The book is filled with interesting matter, and in this notice we will mention some of the many tidbits which are offered.

One of the most interesting subjects touched upon, all too briefly be it said, is that wonderful instinct of bird migration. It seems incredible that out of twenty-five species of aquatic birds, thirteen are visitors from North America, several of them breeding in the Arctic regions and crossing the whole tropical zone to winter, or rather to summer, on the pampa. In September and even in August they begin to appear on the pampa-plover, tatler, god

wit, curlew, "piping the wild notes, to which the Greenlander listened in June, now to the gaucho herdsman on the green plains of La Plata, then to the wild Indian in his remote village, and soon, further south, to the houseless huanaco-hunter in the gray wilderness of Patagonia." Of the god wit― Limosa hudsonica - some go north in March to breed; while later in the season (May) others come from the south to winter on the pampas. The north-flying birds travel thousands of miles to the hundreds traversed by those from the south. It is considered probable that these last have their breeding-places on the as yet undiscovered Antarctic continent, which they have left, after breeding, in time to winter on the pampas.

Numerous

Another interesting chapter is that upon the Puma. facts are given to show that this animal, contrary to the habits of all the other wild Felida, is a friend of man, not only refraining from attacking him, but actually protecting him from the attacks of other animals, like the jaguar for example. One instance of this must suffice. During the course of an extended hunt one of the men fell from his horse, and in falling broke his leg. His companions did not notice his loss until evening, and the next morning he was found where he had fallen. He related that while lying there a puma had prowled about the vicinity but did not attempt to harm him. About midnight he heard the roar of a jaguar, and between that time and morning he several times saw the two animals engaged in fierce fights, the puma preventing the jaguar from attacking the prostrate and helpless man.

In discussing the question of fear in birds, Mr. Hudson discards the idea that it is only found in those which have been persecuted by man, and advances the theory that the older birds teach the young ones to fear their enemies. So strong is the habit of attending to the warning or danger note uttered by many birds, that when a nestling is hammering at its shell and seeking to reach the outer air, uttering meanwhile its feeble "peep," "if the warning note is uttered, even at a considerable distance, the strokes and complaining instantly cease, and the chick will then remain quiescent in the shell for a long time, or until the parent by a changed note, conveys to it an intimation that the danger is over."

Mr. Hudson is not content to record the observations he has made. He seeks also to explain, sometimes plausibly, sometimes perhaps not so well, many of the facts. For example, we are all familiar with the, to us, absurd cackling of a hen when she has laid her egg. She wants the whole world to know it. Obviously it would in a wild state be a serious objection, and be decidedly injurious to the species as a whole, to have all the egg-feeding snakes and mammals apprised of the fact that a new egg had been laid for them to seek. The author therefore contends that this habit is a perversion of the original instinct, and that while it now serves no purpose or a bad one, originally it was useful. He finds in a certain half-wild fowl of the pampa, a babit of making her nest sometimes 400 or 500 yards away from the feedinggrounds. After the egg is laid the hen flies directly from the nest 40 or 50 yards and then, still silently, runs along to the feeding ground. Then only does she give vent to a low cackle. The cock, if within hearing, answers her, runs to her, and the cackling ceases. "If," says Mr. Hudson, "we may assume that these fowls, in their long, semi-independent existence in La Plata, have reverted to the original instincts of the wild Gallus bankiva, we can see here how advantageous the cackling instinct must be in enabling the hen in dense tropical jungles to rejoin the flock after laying an egg. If there are egg-eating animals in the jungle, intelligent enough to discover the meaning of such a short, subdued, cackling call, they would still be unable to find the nest by going back on the bird's scent, since she flies from the nest in the first place."

In a chapter on spiders mention is made of the many strange and wonderful features known in connection with them. Some spin a wonderfully complex and beautiful web; some live on or in the ground; many simulate inanimate objects or death itself. Of two species belonging to the same genus, one is green, while another is like a withered or dried-up leaf. The first, when disturbed, falls rapidly to the ground like a fresh green leaf broken from a twig; but the second falls slowly like a very light, dried,

and withered leaf. Some of the spiders are very large and will chase a man from thirty to forty yards, keeping pace with a slowtrotting horse. An instance is related where one ran up the lash of the author's riding-whip to within three or four inches of his hand, and would have bitten him had he not thrown the whip away. Some rather fanciful speculations are indulged in when considering how a man-like monkey would act were he to have a cord permanently attached to his waist, as the spider may be considered to have his web-making material.

In an interesting chapter on music and dancing in nature, accounts are given of the habit as indulged in by many kinds of birds. Not the least strange of these is that of the spur-winged lapwing. These birds live in pairs, each pair jealously guarding its own chosen ground. But frequently one of a pair will fly off to visit a neighboring couple, leaving its mate to guard the ground. The visitor is graciously received, and the performance gone through with is described as follows: "Advancing to the visitor they place themselves behind it; then all three, keeping step, begin a rapid march, uttering resonant drumming notes in time with their movements; the notes of the pair behind being emitted in a stream like a drum-roll, while the leader utters long single notes at regular intervals. The march ceases; the leader elevates his wings and stands erect and motionless, still uttering loud notes; while the other two, with puffed-out plumage and standing exactly abreast, stoop forward and downward until the tips of their beaks touch the ground, and, sinking their rhythmical voices to a murmur, remain for some time in this posture. The performance is then over, and the visitor goes back to his own ground and mate to receive a visitor himself later on."

We have given here but a bare outline of some of the interesting chapters of the book. The one dealing with the dying-place of the huanaco attempts to explain the habit the animals have of returning to a remote place in which to die. It is traced back to a probable origin in ancient times when the animals herded together in winter for protection and warmth, and the idea is advanced that at present the habit is an aberrant and perverted instinct which has descended by inheritance. When the animal feels the pangs of approaching death, its feelings impel it to the spot where long ages ago its ancestors, with their fellows, found refuge and relief. Mr. Hudson thus regards the habit, not as going to a place to die, so much as going to a place to recover health. Other chapters deal with the odoriferous skunk, of which numerous anecdotes are told; with mimicry and warning colors in grasshoppers; the value and importance of the mosquito in the economy of nature and the question why it possesses a bloodsucking apparatus in such perfection, while scarcely one out of many hundreds of thousands ever tastes blood. The hummingbirds are treated of in another chapter, while in still another is given a full account of a large family of birds known popularly as "wood-hewers." The biography of the vizcacha, the prairiedog of the pampa, is given in full; while an account of certain birds and animals seen once or twice and then lost, never to be again brought to view, reminds one that disappointment sometimes waits upon the investigator into nature's secrets. The book is an interesting one, and we believe worthy of an extended circulation among lovers of natural objects. JOSEPH F. JAMES.

Washington, D.C., Aug. 22.

Mineralogy. By FREDERICK H. HATCH. London, Whittaker & Co. 12°. $1.

DR. HATCH has brought together the most essential principles of mineralogy, and embodied them into what is really an abridgment of a larger treatise. He experiences the difficulty felt by earlier authors of making popular conceptions of geometrical figures and relations, and relieves it so far as is possible by stating the principles of their construction and by giving graphic representations of the perfect solids and diagrams illustrative of the crystallographic axes. There is a very wise selection of the more important figures described. Throughout the descriptions of crystalline form, chemical composition, and the various physical properties, including the choice of the minerals described, the author has shown that he knows what selection should be made in

order that the most essential features shall be presented. He is evidently a master of the whole science, and not an amateur content to explain the familiar portions and to overlook the difficult topics needful to make the sketch symmetrical. Wisdom is also shown in the classification and description of the minerals. The thoroughly scientific arrangement by chemical character, of use to the learned, is laid aside for the following practical scheme: First, the rock-forming minerals, such as are world-wide, and extend through the whole crust; second, the ores; third, the salts and useful minerals supplementary to the ores; and fourth, the gems and precious stones. Under the first head there is presented the important distinction of those that have been formed secondarily in contrast with those that were original. We think the author might wisely have devoted three or four pages, instead of a brief paragraph scarcely exceeding fifty words, to the hydro-carbons. No effort is made to describe the phenomena connected with refraction and polarization, nor to the microscopic structure, nor to petrography.

Notes and Examples in Mechanics. By IRVING P. CHURCH. New York, John Wiley & Sons, 1892.

THIS work, as stated in the preface, is "a companion volume to the writer's Mechanics of Engineering,' and contains various notes and many practical examples, both algebraic and numerical, serving to illustrate more fully the application of fundamental principles in mechanics of solids; together with a few paragraphs relating to the mechanics of materials, and an appendix on the "Graphical Statics of Mechanism." A knowledge of the elements of trigonometry and calculus is assumed.

The work is clear and practical. Many problems are first treated analytically, then by assuming numerical values for the several algebraic quantities. English units are used. Engineering data are drawn from well-known and reliable authorities.

Among the structures and machines discussed (after the necessary exposition of general principles) are the bell crank, simple

Publications Received at Editor's Office.

THIS elementary Treatise belongs to Whittaker's "Library of Popular Science." The undulatory theory is presented in clear and non-mathematical language, and the various phenomena of common observation are explained on this theory.

In a very lucid and attractive style, the author discusses such topics as reflection, refraction, color, optical instruments, the chemical action of light (as in photography), polarization, and fluorescence. The cuts are abundant and well drawn.

The appendix contains an annotated list of elementary works on light, color, spectroscope, etc.

Chemical Calculations, with Explanatory Notes, Problems, and Answers. By R. LLOYD WHITELEY. London and New York, Longmans, Green & Co. 1892.

A WIDE range of topics is included in these hundred pages; as metric system. thermometric scales, density and specific gravity, percentage composition of compounds, calculation of empirical formulæ, volume of gases, calculations depending on chemical equations, combination of gases by volume, calculation of the results of quantitative analysis, atomic weight determinations, gas analysis, absorption of gases by liquids, molecular weights, calorific power and calorific intensity.

The problems on molecular weights are not confined to vapor densities; but the more recent methods of freezing points (Raoult) and boiling points (Beckmann and Wiley) are duly explained.

The table of atomic weights is based upon O= 16, and agrees, for the most part, with Ostwald's "Outlines of General Chemistry;" thus H = 1.003, in accordance with the older determina

Wants.

GRADUATE of the University of Pennsylvania

States. Washington, Government. 8°. 678 p. GARNER, R. L. The Speech of Monkeys. New York, Charles L. Webster & Co. 8°. 233 p. JACKMAN, WILBUR S. Nature Study for the Common Schools. New York, Henry Holt & Co. 12°.

448 p.

MERRILL, GEORGE P. The Materials of the Earth's Crust. Washington, Government. 8°. Paper.

87 p. SALTER, WILLIAM M. First Steps in Philosophy. Chicago, Charles H. Kerr & Co. 12°. 155 p. $1. U. S. DEPARTMENT OF AGRICULTURE. Insect Life Washington, Government. 8°. Paper. 90 p. "WATERDALE." Researches on the Dynamic Action and Ponderosity of Matter. London, Chapman & Hall, 12°. 309 p.

members.

experience desires to give his services and a cabinet of 25,000 specimens, all named, with about the same number of duplicates, in minerals, crystals, logical specimens and woods to any institution derocks, gems, fossils, shells. archæological and ethnosiring a fine outfit for study. The owner will increase the cabinet to 50,000 specimens in two years and will act as curator. Correspondence solicited M.D., Ph.D., San Francisco, Cal., General P. O. from any scientific institution. J. W. Hortter, Delivery.

WANTED. A position as zoological artist in con

rection with a scientific expedition, institution or individual investigations. Experienced in microscopic and all scientific work. References given if desired. Address J. HENRY BLAKE, 7 Prentiss Place, N. Cambridge, Mass.

YOUNG MEN destined for a medical career may

ington, Government. 8°. Paper. 30 p.

WELLS, CHARLES R. Manual of the Natural Movement Method in Writing. Syracuse, C. W. Bardeen. Sm. 4°. Paper. 44 p. 25 cts. WILLIAMS, SAMUEL G. The History of Modern Education. Syracuse, C. W. Bardeen. 129. 403 p. $1.50.

Reading Matter Notices.

Ripans Tabules: best liver tonic.

Ripans Tabules cure jaundice.

FOR SALE.

ΤΟ

thereto, at the same time, if desired, pursuing the so-called elementary medical studies. Advanced students can have clinical instruction, use of modern text books, etc. Will take one or two students into my family and office. Such must furnish unexceptionable references. Quizzing by mail. Address Dr. J. H. M., in care of 417 Adams Avenue, Scranton, Pa.

type specimens and thousands of duplicates. For further information address

JOSEPH F. JAMES,

U. S. Department of Agriculture,
WASHINGTON, D. C.

AYOUNG MAN with a thorough training in Analytical Chemistry (including analysis of minerals, food, water, etc), and holding a diploma of the

timonials, desires a position as Analytical Chemist or as assistant to such. Address to WM. LAWSON, 16 Washington Ave., Toronto, Ontario.

A

tions of the ratio O: H. For many of the problems, however, the atomic weights are rounded to whole numbers, except Cl = 35.5.

The work is recommended as a well-planned text-book of the subjects indicated.

Mechanics for Beginners. Part I. Dynamics and Statics. By J. B. LOCK. London and New York, Macmillan & Co., 1891.

THIS is a carefully-prepared elementary text-book, presenting the subject in the following order: rectilinear motion, motion in one plane, forces acting at a point, parallel forces, machines (including friction), uniform motion in a circle, energy, the pendulum. The definitions are clear and examples abundant. The demonstrations presuppose a knowledge of trigonometry.

English units are employed throughout. The following terms are convenient (in the absence of metric units), but not very familiar in this country: velo, the velocity of one foot per second; celo, the acceleration of one velo per second; poundal, a force producing one celo on one pound; and foot-poundal, the work done by one poundal acting one foot.

While this work shows marks of thoroughness, it seems a great pity to ignore the international system of weights and

measures.

Elementary Lessons in Heat. By S. E. TILLMAN Revised Edition. New York, John Wiley & Sons, 1892.

THESE lessons, prepared as a short course for the U. S. Military Academy, present the most essential and practical aspects of the subject, in a clear and descriptive manner. The language of

trigonometry and differential calculus are scarcely introduced, even in discussing the conduction of heat. English units are employed, for the most part. The various kinds of thermometers and other instruments required by observers are explained; and the last two chapters are devoted to meteorology.

Forty-six numerical problems are added in this edition, illustrating thermometric scales, linear and cubic expansion, properties of gases, specific heat, latent heat, relative humidity, and mechanical equivalent of heat.

. AMONG THE PUBLISHERS.

THE September number of The Mother's Nursery Guide contains medical articles on "Natural and Artificial Feeding of Infants," "A Short Talk about Disease Germs," "Some Common Nervous Diseases," etc. Other subjects are: "A Mother's Duty in Mental Child-Training," "Kindergarten-at-Home Stories," "A Child's Vocabulary," etc.

-All teachers and those interested in the eduction of young children will wish to read the article in The Atlantic Monthly for September by Horace E. Scudder, entitled "The Primer and Literature."' This paper proves in a very logical, clear, and interesting manner that "the time has come when the . . . statement may be made that there should be no break in the continuity of literature in the schools; that from the day when the child begins to hold a book in his hands until the day when he leaves the public school he shall steadily and uninterruptedly be presented with genuine literature; that the primer itself shall serve as an introduction to literature." The paper will well repay careful reading and discussion.

2 OU

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material by the pound, for mineralogists, collectors, colleges, schools, and chemists. Send for 100-page catalogue, paper bound, 15 cents; cloth bound, 25 cents; supplement, 2 cents. GEO. L. ENGLISH & Co., Mineralogists, 733 & 735 B'way, N. Y.