Littell's Living Age,

THE ONLY WEEKLY ECLECTIC. 1844. 1893.

"The Oldest and the Best."

It selects from the whole wide field of EUROPEAN PERIODICAL LITERATURE the best articles by

THE ABLEST LIVING WRITERS
In every department of
Literature, Science, Politics and Art.
OPINIONS.

Only the best has ever filled its pages; the best thought rendered in the purest English. Nothing poor or unworthy has ever appeared in the columns of THE LIVING AGE."-The Presbyterian, Phila.

"Considering its size, it is the cheapest of literary periodicals, and no collection of magazine literature is complete without this foremost of eclectics."-Educational Courant, Louisville, Ky.

"It is one of the few periodicals which seem indispensable. It contains nearly all the good literature of the time."-The Churchman, New York.

"The fields of fiction, biography, travel, science, poetry, criticism, and social and religious discussion all come within its domain."-Boston Journal.

"To read it is itself an education in the course of modern thought and literature."- Buffalo Commercial Advertiser.

Published WEEKLY at $8.00 a year, free of postage.

Club Rates.

For $10.15 THE LIVING AGE and SCIENCE will be sent for a year, postpaid.

Rates for clubbing THE LIVING AGE with other periodicals will be sent on application.

Sample copies of THE LIVING AGE, 15 cents each. Address,

Littell & Co., 31 Bedford St., Boston, Mass.

BRENTANO'S,

Publishers, Importers, Booksellers.

Ticknor & Co., 211 Tremont St., Boston. branches of science, and in all languages.

"Extremely useful to beginners and collectors for the region it covers."-Wm. H. Dall.

MOLLUSKS OF THE

We make a specialty of technical works in all Subscriptions taken for all American and foreign | scientific periodicals.

Our Paris and London branches enable us to import at shortest notice and lowest prices. REPORTS OF SCIENTIFIC SOCIETIES, MONOGRAPHS, GOVERNMENT REPORTS, etc. Correspondence solicited.

All books reviewed in SCIENCE can be ordered

from us. SEND FOR A SAMPLE COPY OF BOOK CHAT. A Month$1.00

ATLANTIC COAST OF THE UNITED STATES, South to Cape Hatteras. By AUSTIN C. APGAR. This work contains a key to all the genera, a glossary of Molluscan terms, de-y Index of the Periodical Literature of the World. scriptions of all the species of shells, and over sixty illustrations. Price, Bound in Cloth, Postpaid, $1. For sale by AUSTIN C. APGAR, 511 East State St., Trenton, N. J.

per year.

BRENTANO'S, Union Square, New York,

Chicago, Washington, London, Paris.

LIGHT, HEAT AND POWER.

Manufacturer and Builder. THE INDEPENDENT GAS JOURNAL

Published Monthly. A handsomely illustrated mechanical journal, edited by DR. WILLIAM H. WAHL. Every number consists of 48 large quarto pages and cover, filled with useful information on all subjects of a practical nature. Specimen copy free. For sale by all newsdealers." Agents wanted everywhere. Address

HENRI CERARD,

OF AMERICA.

PUBLISHED MONTHLY AT PHILADELPHIA.

Subscription, $3.00 per year.

P. O. Box 1001. 83 Nassau St., N. Y. POPULAR MANUAL OF VISIBLE SPEECH AND

A FIRST-CLASS WEEKLY MEDICAL NEWSPAPER. ESTABLISHED 1828. Terms of Subscription: In the United States, and to Canada and Mexico, $5 00 a year in ad vance. To Foreign Countries embraced in the Universal Postal Union, $1.56 a year additional. Single numbers, 15c. Ten consecutive numbers free by mail on receipt of $1.00.

This JOURNAL circulates chiefly through the New England States, and is seen by the great majority of the profession in that important district. As a means of reaching physicians it is unequalled. It is under the editorial management of Dr. George B. Shattuck, assisted by a large staff of competent coadjutors. Subscriptions and advertisements received by the undersigned, to whom remittances by mail should be sent by money-order, draft or registered letter.

RACES AND PEOPLES.

By DANIEL G. BRINTON, M.D. "The book is good, thoroughly good, and will long remain the best accessible elementary ethnography in our language."-The Christian Union.

"We strongly recommend Dr. Brinton's Races and Peoples' to both beginners and scholars. We are not aware of any other recent work on the science of which it treats in the English language." -Asiatic Quarterly.

"His book is an excellent one, and we can heartily recommend it as an introductory manual of ethnology."-The Monist.

"A useful and really interesting work, which deserves to be widely read and studied both in Europe and America."-Brighton (Eng.) Herald.

"This volume is most stimulating. It is written with great clearness, so that anybody can understand, and while in some ways, perforce, superficial, grasps very well the complete field of humanity."The New York Times.

"Dr. Brinton invests his scientific illustrations and measurements with an indescribable charm of narration, so that 'Races and Peoples,' avowedly a record of discovered facts, is in reality a strong stimulant to the imagination."-Philadelphia Public Ledger.

"The work is indispensable to the student who requires an intelligent guide to a course of ethnographic reading."-Philadelphia Times.

Price, postpaid, $1.75.

THE AMERICAN RACE.

By DANIEL G. BRINTON, M.D. "The book is one of unusual interest and value."Inter Ocean.

"Dr. Daniel G. Brinton writes as the acknowledged authority of the subject."-Philadelphia Press.

"The work will be of genuine value to all who wish to know the substance of what has been found out about the indigenous Americans."-Nature.

"A masterly discussion, and an example of the

successful education of the powers of observation." -Philadelphia Ledger.

Price, postpaid, $2.

The Reichert III (vertical, No. 8) is a favorite pattern for laboratory work, and is fitted with his best lenses.

We are prepared to import the above instruments, duty free, for educational institutions, at extremely low prices. Correspondence Solicited.

QUEEN & CO., Sole Agents. Philadelphia.

1893 Catalogue

of Books on Building, Painting, and Decorating, also Catalogue of Drawing Instruments and Materials, sent free on application to

Wm. T. Comstock, 23 Warren St., New York.

NEW YORK, AUGUST 4, 1893.

THE FLORIDA LAND TORTOISE-GOPHER, GOPHERUS

POLYPHEMUS.

BY HENRY G. HUBBARD, DETROIT, MICH.

It seems very strange that so little has been known, or at least has been published about the habits of this very common animal. Winter visitors to Florida and the Gulf States often observe their burrows on the sandy ridges, each with its yawning entrance and scattered mound of subsoil, and are not unlikely to mistake them for the woodchuck holes with which they are familiar at the north. It is the permanent resident, however, that is most likely to have some acquaintance with the animal itself; for only in the hottest weather and at noonday does the gopher leave its burrow to feed upon the surrounding grass and herbage.

In summer, when the thermometer is in the nineties, the animal comes forth daily, some time between the hours of eleven A.M. and two P.M., and takes a careful look around to assure itself that no danger threatens. Then, if no ominous sounds disturb the stillness of the sultry air, it raises itself high on its ungainly legs and starts briskly off for the nearest patch of grass or cultivated field.

For about an hour the gopher wanders about with its long neck outstretched and plucks ravenously at every green vegetable within its reach. Often, indeed, in its eagerness it cracks up and swallows dead twigs and dry leaves together with the more succulent food, until its ravenous appetite is appeased. It then retires to the bottom of its burrow in the moist, cool sand, there to remain until the morrow or, if the season be rainy, until the next dry, hot day.

The gopher is a very timid and alert animal, and although it feeds with great gusto and apparent abandon, it is seldom so absorbed in its work that it fails to hear the sound of approaching footsteps. The near approach of any large amimal sends it scurrying back to its hole. It requires lively work to head off its retreat, but if surprised and captured at a distance from its hole, like other turtles, it retires into its shell, and, drawing its plethoric and scaly fore paws like double doors over the front of its shell, it resigns itself supinely to its fate, and never under any circumstances attempts to bite or otherwise defend itself.

In winter the gopher very rarely quits its burrow, and comes forth to feed only on the very hottest days at noon. In the warm Florida soil it is never torpid, but remains quiescent at the end of its gallery awaiting the return of dog day weather.

A well grown gopher measures 10 inches in length by 74 inches in width and 4 inches in thickness, and weighs about 6 pounds. Individuals are sometimes found measuring 12 × 9 × 5 inches, and weighing 9 or 10 pounds.

They are sold in the markets of many towns at high prices, and are eaten by the negroes and lower classes every where in the south. The flesh is excellent in quality, very tender, of a rich red color and has the appearance, flavor and odor of beef. But the supply of meat obtainable even from individuals of the largest size is scanty, the greater part of the body cavity being occupied by the enormous gut crammed with grass and the long intestines filled with wads of fibrous dung. The flesh is greatly relished by all carnivorous animals, but a gopher of average size has little to fear from their attacks. The largest dogs are unable to bring their canine teeth to bear upon any vulnerable part unless the specimen is young and small enough to be taken into their mouths.

In May or June the female deposits in the sand outside of her burrow from one dozen to twenty eggs. The eggs are perfectly

spherical, pure white in color and have a diameter of 1 inches. More beautiful objects can hardly be found to grace an oölogical cabinet.

The burrows of the gopher are excavated by the aid of a remarkable spade-shaped projection on the front of the under shell, assisted by the powerful fossorial front legs, which are armed for this purpose with strong blunt claws.

In the sandy uplands of Florida the galleries descend at an angle of about 35°, and reach a vertical depth of seven to nine feet from the surface of the ground. They follow a straight course unless deflected by a root or some other obstruction and usually terminate in a layer of indurated soil. The length of the gallery varies from twelve to eighteen feet. The temperature at the lower end does not vary greatly throughout the year, and will generally not fall below 74° in winter nor rise above 79° in summer. The conditions as to moisture are probably equally constant. At Crescent City, Fla., where these observations were made, the permanent water table lies at an average depth of eighteen feet. The burrow of a gopher once completed becomes its permanent residence, and it is with extreme difficulty that the animal can be compelled to vacate and excavate a new home.

It is inhabited by the same individual for long periods of time, and if the popular belief in the great age attained by turtles in general and the land tortoise in particular is well founded, some of these reptilian domiciles may have antedated the present century, and even rival in antiquity the dwellings of man. Certain burrows in this vicinity are pointed out as having been in existence twenty-four years ago, when the oldest orange groves were planted. This necessarily implies a continuous occupancy by the same individual tortoise during that period, since if the galleries are abandoned they shortly become filled up and obliterated in our shifting sand.

Every naturalist will appreciate under the above showing what unusually favorable conditions here exist for the preservation of animal life, and will not be surprised to learn that these little sand caves, with their equable climate, permanent and abundant moisture, perpetually and hospitably open to the outer air, afford an asylum and a domicile to a most interesting assemblage of animals. The list of these, when it shall have been completed, bids fair to become a long one.

Not only the Florida burrowing owl, the rattlesnake, the rabbit, the raccoon and the opossum find in them a temporary shelter, but another vertebrate also, a frog, here takes up its permanent abode and lives on terms of perfect friendship with the gopher. This frog is the sub-species Rana areolata æsopus, a beautiful form, with soft subterranean coloration and crepuscular, toad-like habits.1

It is not at all rare, nearly every gopher hole harbors one or several specimens. They may be seen at evening sitting just outside the entrance of the burrow, and frequently in the morning or on cloudy days their softly radiant eyes may be detected gleaming out of the shadows a few feet back from the entrance. It is not easy to capture them, except with a baited hook and line, for at the slightest alarm they leap quickly down the yawning throat of the gallery and disappear from view. Specimens of this frog have been seen which would weigh more than a pound, and individuals of colossal proportions are reported to exist.

In January and during July of the present year more than a dozen species of articulates have been discovered living in the gopher holes. The majority are undescribed and new to science.

1 Mr. Fred'k C. Test, of the National Museum, who kindly determined the species, writes: "Only one specimen, the type, is in the museum collection or presumably in any other." The type specimen came from Micanopy, Fla., probably without notes of habits, etc.

Two only are parasitic upon the gopher: (1) a large tick, which fastens itself upon the skin of the animal or to the sutures of the shell; (2) a gigantic acarus, a quarter of an inch in length, which does not remain upon the body of the gopher but attacks it within the nest, which, like the bed-bug, it never quits. Some of the burrows are infested with these blood-sucking mites and others appear to be entirely free from them.

The dung of the gopher furnishes food to five beetles and one interesting caterpillar of a moth. All of these are new and peculiar forms, presenting characters that indicate subterranean habits of life. A large wingless cave cricket, apparently a Phalangopsis, swarms in all the burrows.

Three predatory beetles, one of which, a new species of Anthicus, may prove to be a prowler from without, have been found within the galleries.

A very large specimen of the whip-tail scorpion (Telephonus) was found in one of the burrows. It was living in a short gallery of its own, which opened into the nest of the gopher at the lowest level. A minute Pseudo-scorpion is also found at the lower end of some of the burrows.

A flea of undetermined species, of which a single specimen was found in one of the holes, may prove to be an intruder, left behind possibly by some mammalian visitor.

The following is a review of the animal parasites and messmates of the gopher:

Vertebrate.

1. The gopher frog, Rana areolata æsopus.

Articulates.

1. Copris, new sp. Feeding upon dung of gopher.
2. Onthophagus, sp. Feeding upon dung of gopher.
3. Saprinus, new sp. Feeding upon dung of gopher.
4. Saprinus, sp. Feeding upon dung of gopher.
5. Aphodius, new sp. Feeding upon dung of gopher.
6. Staphylinide, probably a Philonthus. Predatory.
7. Trichopteryx, sp. A species found also outside.

8. Anthicus, new sp. One specimen only.

9. Pyralid moth. Caterpillars feeding upon dung. 10. Cave cricket (undetermined).

11. Acaride parasite of the gopher (undetermined).

12. Gopher tick (undetermined).

13. Pseudo-scorpion (undetermined).

14. Whip-tail scorpion. Predatory intruder.

15. Flea, probably a mammalian parasite.

Most of the insects have been submitted to Mr. E. A. Schwarz, of the Department of Agriculture, Washington, D. C., and to him I am indebted for the determinations given above.

NEW METHODS OF TREATING THE SICK.

BY WILLIAM C. KRAUSS, M.D., BUFFALO, N. Y.

ON June 1, 1889, Professor Brown-Séquard presented a communication to the Société de Biologie of Paris on a new method of therapeutics. It seems that Brown-Séquard had been at work on this project for many years, for, in 1869, he expressed a belief that if it were possible to inject spermatic fluid into the veins of old men they would experience a rejuvenation, sexually, mentally, and physically. After repeated experiments upon rabbits, dogs, and guinea pigs, he, in a true scientific spirit, injected some of the testicular fluid into his system, and his experiences and results form the most interesting part of his memorable communication to this learned society. "The author of this communication, now 72 years old, has for the past twelve years watched his physical powers slowly and continually decline. The laboratory work has become laborious and heavy, and after each meal I have been obliged to take a short nap. After the third injection a complete change took place. The work in the laboratory has become agreeable, not the least fatiguing, and after three and a half hours of such work I have been able to edit a memoir. The dynamometer showed an increase of 6.7 kilogrammes, the bowels regained their former activity, and, in short, I have regained all that I have lost."

These results, coming from one of the ablest physiologists in France, yea, of the world, were in an incredibly short space of time dispatched to all corners of the earth, and Brown-Séquard's "Elixir of Life," erroneously called, was being tested by hundreds of doctors and would-be scientists.

Enthusiastic reports are not easy to corroborate, and the Elixir of Life was doomed to bitter disappointment. At first encouraging results were reported by a class of observers least fitted to test the virtues of the new discovery, but in a short time the whole proceedings were looked upon with disdain and distrust.

Not so in France, Brown-Séquard published several later reports with equally good results, and the experiments were further conducted by some of his co-workers and students. The bypodermic injections of testicular juice gave encouraging results in anæmia, organic diseases of the brain and spinal cord, cachexia, tuberculosis, and in many of the chronic diseases. It was also found that ovarian juice gave nearly the same results as did the testicular juice. Thyroid juice. It has been definitely proven that removal of the thyroid glands from a dog will be followed by death. Gley, in his experiments, decided to inject the juice of thyroid glands in dogs thus deprived of these glands, and, instead of dying, they recovered without any serious difficulties. In the human family it has been found that after removal of the thyroid gland or the destruction of this gland through disease, that a certain train of symptoms will develop, which had received the name of myxœdema, a disease characterized by swelling of the face, body, and extremities, loss of hair, sub-normal temperature, etc. Horsley attempted to transplant the thyroid gland of animals to these patients, and met with partial success. Dr. Murray of Newcastle, England, then injected hypodermically a glycerine extract of thyroid gland into patients suffering with myxedema, and his efforts were rewarded with beneficial results. Brown-Séquard and D'Arsonval were conducting similar experiments about the same time with equally good success. It was found, however, that the injection of this substance was followed in many cases with pain, inflammation, and abscess formation. To overcome these hindrances, Fox of Plymouth and Mackenzie advised and practised the treatment of myxedema by feeding with sheeps' thyroid glands, and the results seemed to be in every way satisfactory.

The writer has had a little experience in treating two cases of myxoedema, but he has been unable to attain anything like the results claimed by the English and French writers. In fact his experience has been negative, not even obtaining temporary improvement.

MacAlister of England has treated cases of pseudo-hypertrophic paralysis with injections of thymus gland extract; also a case of lymphadeuoma with a mixture of red and yellow marrow, with seemingly good results.

He

Dieulafory of Paris has injected extracts of the cortical portion of the kidney into patients suffering with Bright's disease. proposes the name Nephrine for this particular fluid Comby and Dieulafory have also injected the extract of pancreas in cases of diabetes, with temporary good results.

Spermine is the name of another fluid extract derived from Brown-Séquard's testicular juice, its action seems to be similar to the testicular juice, acting upon the motor areas of the cerebrospinal axis, increasing the strength of the arms and legs, regulating the sexual, urinary, and digestive functions, and in improvement of the general sensibility.

American experimenters have not been idle during the rise of this fin de siècle therapeutics. There are now houses in New York manufacturing animal extracts known as cerebrine, medulline, testiculine, musculine, and other newly-coined-word remedies which have been recommended in the various diseases of the human body. Personally, the writer has had experience with cerebrine only, and, if he has noticed any results, they have been but temporary. Perhaps they do not even deserve the name "result," only a reaction had set in. Those of the writer's friends who have had experience with these remedies have also obtained negative results. The injection of water and glycerine has succeeded in accomplishing exactly what the animal extracts have done.

What the outcome of this innovation will be, or where it will end, is at present impossible to say. The field is so broad and the inclination to experiment so great that, in all probability, some little time will elapse before the returns will all be in. Whether these extracts exert any specific action, or whether the results thus obtained have been through "suggestion" and auto-suggestion, is likewise hard to explain, the writer is inclined to the latter view, that "suggestion" has been the specific" agent.

NOTES ON ARSENIC.

BY JAS. LEWIS HOWE, POLYTECHNIC SOCIETY, LOUISVILLE, KY. NOTWITHSTANDING the well recognized danger of arsenical greens as coloring materials, their use is still far too common, especially in green enameled papers for covering boxes and for more reprehensible purposes. I cite two cases in point.

1. Some time since my attention was called to some so-called "Kiss Candies" for sale in a little variety shop, largely patronized by the children of a neighboring public school. These candies were squares of caramel, etc., each wrapped up with a verse of poetry (?) in a piece of colored paper, together with other candies not wrapped. Some of these papers were colored with anilin dyes, but a very considerable number were green enameled papers. An examination of several of these latter revealed the following:

Paper I. Bright-green surface, 50 square centimetres, arsenic found (estimated as arsenious oxid), 0.0285 of a gram.

Paper II. Light-green surface, 50 square centimetres, arsenic found, 0.0062 of a gram.

Paper III. Dark-green surface, 50 square centimetres, arsenic found, 0 0093 of a gram.

Paper IV. Bluish-green surface, 47 square centimetres, arsenic found, 0.0209 of a gram.

In the latter cases the enameled surfaces appeared much abraded, doubtless by contact with the other candies.

It is needless to say that here was not only a grave danger of the surfaces of the candies containing considerable arsenic, but the well-known habit of young children of putting everything bright colored in the mouth, might have easily resulted in taking a toxic dose.

2. Very recently there has appeared in the market a natural leaf twist chewing tobacco, wrapped around with a strip of green enameled paper three-fourths of an inch wide and about six inches long, fastened to the tobacco by a tack. The surface of this paper is an arsenic green. An examination was made of the twist by cutting off the exterior and using Reinsche's test. Distinct traces of arsenic were found. The quantity from a single twist was far too small to be dangerous, but it is needless to say that the practice of using arsenic paper under such circumstances should be condemned, and the manufacturers of the twist were cautioned on the point. The arsenic found in the tobacco doubtless came, by abrasion, from the paper wrapped around it, but there is another possibility. It is more or less widely known that Parisgreen is used by tobacco-growers against the tobacco worm. While in general, when properly used, probably no danger is to be apprehended, it has occurred in my knowledge that tobacco has been sprayed very shortly before gathering. This would seem to be dangerous, and investigations upon this point are being now carried out.

As regards the detection of arsenic in medico-legal cases, atten. tion has been called by Dr. Bernard Dyer in the Proceedings of the Chemical Society' to the fact that in certain cases, at least, a large proportion of the arsenic is precipitated upon the zinc in Marsh's test. The following is an observation in point. Arsenic was recovered in a certain case by Reinsche's test on six pieces of copper foil, each 20 square centimetres surface. Three of the pieces were divided, and from each the arsenic was sublimed in well-defined crystals, which could be identified without difficulty. From the other three pieces all the arsenic was sublimed, dissolved, and submitted to Marsh's test. Only the very slightest trace of a mirror was found, not enough to identify it as arsenic in a doubtful case. In this case, as in that of Dr. Dyer, cast zinc was used. 1 Proc. Chem. Soc., 1893, p. 120.

Another recent case illustrates the necessity of the physicians who perform the autopsy preserving other organs than the stomach. G. had given her husband coffee from a pot in which she bad emptied probably a whole box of Rough on Rats. He drank two cups, containing probably in the neighborhood of 7 grams. The coffee left, which I afterwards examined, was practically a saturated solution of arsenious oxid. Death ensued in four hours. The stomach was brought me, and was found to be empty, and much inflamed. Using the whole stomach, but a very small quantity of arsenic was found, evidently only what the walls of the stomach as a tissue could absorb, and far from enough to have produced death. The corroborative testimony was, however, sufficient to secure the woman's conviction.

Brodie's statement that when arsenic is taken in solution no trace of it will be found in the stomach is too broad, but it is imperative that in such cases other organs, notably the liver (as well as spleen and kidneys), should be preserved for analysis.

In my own experience, Reinsche's test, when carefully carried out, is far more satisfactory and no less certain in testing for the presence of arsenic than Marsh's. It can be readily learned by medical students and used practically by the physician, which is not true of Marsh's test. In order to secure well-defined arsenic crystals in Reinsche's test with a minimum of arsenic, I have found it desirable to use electrolytic foil, to roll the strip very closely, and to sublime in a tube of the smallest possible diameter.

A NEW IDEA IN MICROSCOPE CONSTRUCTION.

BY C. W. WOODWORTH, UNIVERSITY OF CALIFORNIA, BERKELEY, CAL. EVERYONE who has worked with the microscope, especially in studying rather large objects with medium and low powers, has felt the need of a better means of orientation than those at present available.

Stage forceps admit of complete rotation in one direction and some degree of motion at right-angles to this by raising or lowering the object and readjusting the focus. Ordinarily, any change in the direction of the object requires this readjustment of the focus, and generally the part to be studied is out of the field and must be found as well.

The ideal condition would be to rotate the object at the exact focal point of the microscope, and one can readily see that this could be attained if the object was supported by an apparatus revolving upon two axes at right-angles to each other, which intersect at the focal point, provided neither of these remains fixidly coincident with the optical axis.

There are many ways by which this condition might be attained, but perhaps as simple a modification of an existing stand as could be made with this object in view is a stand I have recently had the Bausch & Lomb Optical Company make for the Entomological Department of the University of California.

The instrument is a "Model" stand with an ordinary revolving mechanical stage. This is supported on a rotating bar, resembling the usual sub stage bar, and provided with a rack and pinion adjustment.

The stage is centred in the usual way, which brings the axis of revolution coincident with the optical axis. The stage bar swings upon a core which is adjustable laterally, so it becomes possible to make the axis of its rotation intersect the optical axis.

These adjustments being made, the instrument fulfils the conditions specified above whenever the focal point is brought to the axis of rotation of the stage bar. Consequently, in using the instrument the tube is brought to a certain position and the focusing of the object accomplished by means of the rack and pinion of the stage bar. The correct position of the tube is determined by trial for each objective, and marks made on the tube to indicate this position.

Different objectives, as those who have used revolving stages must have noticed, have somewhat different optical axes, and there is enough variation with the medium powers to make a centreing nose-piece essential.

While it is mechanically impossible to make all these adjustments perfectly correct, still I find that even with medium powers the object remains in the field during orientation, and that the

fine adjustment is generally sufficient to keep it constantly in focus, and I have no doubt that it might be adjusted well enough to use satisfactorily as high a power as a long focussed quarterinch objective.

Indeed, the instrument has proven to be all that could have been expected of it as an orienting microscope, and, at the same time, its value for ordinary work is is no way decreased, unless the slightly less rigidity of the stage is an objection.

Plans have already been completed for a dissecting microscope for use in my laboratory embodying the same principal but involving greater changes from instruments now in use. The new stand will consist of a stage which remains horizontal, so that insects may be dissected on it under water. The arm is jointed and the lower section bent so that the axes of the two hinges are at right-angles to each other. There will be the necessary arrangements for so adjusting these axes as to make them intersect, and the tube will be fitted with a nose-piece adjustment.

The base will be clamped to the desk for sake of rigidity. The focussing will be all done at the stage, though the tube will move to accommodate the varying focal-lengths of the objectives.

It is expected to use the objective under water, providing it with a hard-rubber shield having a cover-glass on the end. This kind of instrument should be also very useful for the study of aquatic forms.

SUMMER WORK IN MARINE ZOÖLOGY AT NEWPORT.

BY W. E. CASTLE.

OUT on the extreme southwestern point of the Island of Rhode Island, in Narragansett Bay, is Castle Hill, the comfortable residence of Mr. Alexander Agassiz. Against this point the waves of the Atlantic break with full force as they sweep round the east end of Long Island past Point Judith. This is the one rough spot in the trip from New York to Boston by boat.

As the tide comes in at Castle Hill and passes the narrow entrance of the bay, it makes a bend and carries its rich pelagic life into a little cove on the north side of the point. On this cove is Mr. Agassiz's laboratory.

It is a modest-looking little structure, modelled after a Swiss cottage, but within it is a very paradise for the marine zoologist.

Aquaria, tanks, and glassware it contains in abundance, while fresh and salt water are carried in pipes to all parts of the laboratory. Fresh, salt water, and air to aërate the aquaria are pumped in by a wind-mill.

Mr. Agassiz carries on his own investigations in the smaller room at the west end of the building. The larger room of the ground floor each summer he generously puts at the disposal of a certain number of students from the Museum of Comparative Zoology at Cambridge, Mass.

Any day through the summer you may see half a dozen men here industriously bending over their microscopes, studying animals in their living form or preserving material for future study. On account of the extreme moisture of the atmosphere, little balsam mounting or clearing can be done at the sea-shore, so that work of this kind is usually postponed to be done at Cambridge during the fall and winter months.

Each morning at nine o'clock a hack from the boarding-house in town puts the men down at the laboratory door. It calls for them again at five, after their day's work is ended.

About ten o'clock each evening "Thomas," Mr. Agassiz's faithful man-of-all-work, rows slowly up and down the cove skimming the surface of the water with a tow-net. From time to time he lifts the net of fine cheese-cloth carefully from the water, turns it inside out and dips it repeatedly in a bucket of water.

The soup thus obtained is carried into the laboratory, diluted, and poured out into half a dozen glass dishes placed on black tiles.

Around these dishes the men gather upon their arrival in the morning, each furnished with pipettes and watch-glasses of various sizes. Every nook and corner of the dish is carefully scanned with naked eye and with the aid of lens, and in different lights, that no egg or larva, however minute, may escape notice.

After a man has acquired a general knowledge of the pelagic

fauna, he usually confines his attentions to some particular group of animals, and the tow is sorted out and divided accordingly. One man studies the mollusks, another the echinoderms, another the jelly-fishes, and so forth.

The tow is the chief source of material for study. It is supplemented, however, by dredging from the steam-launch, and shore collections at low tide.

The laboratory contains a good library of general works of reference, while literature on special topics is supplied from Mr. Agassiz's private library and from the museum library at Cambridge.

Not least among the advantages afforded to the training investigator are the helpful suggestions of Mr. Agassiz himself, whose long experience in marine work makes him an invaluable adviser.

With such excellent opportunities for advanced work in zoology, it is not surprising that in this little laboratory material has been gathered for many scientific papers of a high order, and that here many of the best zoologists Harvard College has produced have received an important part of their professional training.

BACTERIOLOGY IN THE DAIRY.

BY C. C. GEORGESON, MANHATTAN, KANSAS.

THE bacteria which affect the quality of our dairy products may, for practical purposes, be classed under two heads, namely, those which are beneficial, and those which are injurious, and it is as essential to encourage the one as it is to wage a constant war upon the other. It has been established beyond a peradventure that the pleasant flavor and aroma of good butter are developed by certain species of bacteria present in the cream and instrumental in producing the changes which take place during the process of fermentation usually termed "souring." And it is equally well established that there are certain other species which, if permitted to get the mastery, will, as it were, overpower and neutralize the influences of the former class and give a disagreeable taste and smell to the butter. Both classes are present in all dairies, and the skill and success of the butter-maker depend in large degree on the recognition of this fact and his ability to foster the growth of the beneficial bacteria and to keep the injurious kinds in subjection. His chief weapon against the latter is cleanliness. Filth of every description is their best breeding-ground. But it also happens that the conditions are such, in surrroundings over which the butter-maker has no control, that, in spite of the strictest cleanliness on his part, the injurious organisms propagate too fast and deteriorate his products. Again, it may lie in the health, feed, or other conditions affecting the cows from which the milk is drawn. Under such conditions, what is he to do? It is the solving of this problem which has brought bacteriology into intimate connection with the dairy business; and the honor of solving it and thereby ensuring the production of "gilt-edge" butter under naturally adverse conditions belongs to the Danes.

In practical dairying there are two forms of physical means by which the growth of bacteria may be controlled, namely, cold and heat, relatively speaking. At a temperature at or near the freezing-point the active growth of the bacteria ceases, and hence the reason for keeping the milk cool by the use of ice. The cold produced by the ice does not kill the organisms or purify the milk, it simply retards their multiplication, and thus affords time for the dairy operations to take place before they work injurious changes. Heat, on the other hand, kills the bacteria. At the boiling-point nearly all those forms ordinarily found in milk are destroyed. But, as this high temperature affects the taste of the milk or cream by imparting the characteristic "boiled taste,” in practice the temperature is raised to but 75° or 80° C., at which point the taste is not materially affected, and still the greater portion of the bacteria are killed.

This much known, the Danes have gone a step farther. They have isolated and perpetuated "pure cultures" of those forms which they have found to be beneficial to the production of firstclass butter, and by impregnating the cream, under proper conditions, with these artificially grown bacteria they give their butter the desired flavor and aroma. It is now between two and three