Slike stranica
[merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][merged small][merged small][merged small][merged small][merged small]
[blocks in formation]



.7, 8, 9, 10, 11, 12

..12, 13

[blocks in formation]

IN seeking a means of protection from lightning-discharges, we have in view

two objects, the one the prevention of damage to buildings, and the other

the prevention of injury to life. In order to destroy a building in whole or in

part, It is necessary that work should be done; that is, as physicists express

it, energy is required. Just before the lightning-discharge takes place, the

energy capable of doing the damage which we seek to prevent exists in the

column of air extending from the cloud to the earth in some form that makes

it capable of appearing as what we call electricity. We will therefore call it

electrical energy. What this electrical energy is, it is not necessary for us to

consider in this place; but that it exists there can be no doubt, as it manifests

itself in the destruction of buildings. The problem that we have to deal with,

therefore, is the conversion of this energy into some other form, and the ac-

complishment of this in such a way as shall result in the least injury to prop-

erty and life.

Why Have the Old Rods Failed?

When lightning-rods were first proposed, the science of energetics was en-

tirely undeveloped; that is to say, in the middle of the last century scientific

men had not come to recognize the fact that the different forms of energy-

heat, electricity, mechanical power, etc.- were convertible one into the other,

and that each could produce just so much of each of the other forms, and no

more. The doctrine of the conservation and correlation of energy was first

clearly worked out in the early part of this century. There were, however,

some facts known in regard to electricity a hundred and forty years ago; and

among these were the attracting power of points for an electric spark, and the

conducting power of metals. Lightning-rods were therefore introduced with

the idea that the electricity existing in the lightning-discharge could be con-

veyed around the building which it was proposed to protect, and that the

building would thus be saved.

The question as to dissipation of the energy involved was entirely ignored,

naturally; and from that time to this, in spite of the best endeavors of those

interested, lightning-rods constructed in accordance with Franklin's principle

have not furnished satisfactory protection. The reason for this is apparent

when it is considered that the electrical energy existing in the atmosphere

before the discharge, or, more exactly, in the column of dielectric from the

cloud to the earth, above referred to, reaches its maximum value on the sur-

face of the conductors that chance to be within the column of dielectric; so

that the greatest display of energy will be on the surface of the very lightning-

rods that were meant to protect, and damage results, as so often proves to be

the case.

It will be understood, of course, that this display of energy on the surface

of the old lightning-rods is aided by their being more or less insulated from

the earth, but in any event the very existence of such a mass of metal as an

old lightning-rod can only tend to produce a disastrous dissipation of electrical

energy upon its surface," to draw the lightning," as it is so commonly put.

Is there a Better Means of Protection?

Having cleared our minds, therefore, of any idea of conducting electricity,

and keeping clearly in view the fact that in providing protection against light-

ning we must furnish some means by which the electrical energy may be

harmlessly dissipated, the question arises, "Can an improved form be given

to the rod, so that it shall aid in this dissipation ? "

As the electrical energy involved manifests itself on the surface of conduc-

tors, the improved rod should be metallic; but, instead of making a large rod,

suppose that we make it comparatively small in size, so that the total amount

of metal running from the top of the house to some point a little below the

foundations shall not exceed one pound. Suppose, again, that we introduce

numerous insulating Joints in this rod. We shall then have a rod that experi-

ence shows will be readily destroyed-will be readily dissipated - when a

discharge takes place; and it will be evident, that, so far as the electrical en-

ergy is consumed in doing this, there will be the less to do other damage.

The only point that remains to be proved as to the utility of such a rod is to

show that the dissipation of such a conductor does not tend to injure other

bodies in its immediate vicinity. On this point I can only say that I have

found no case where such a conductor (for instance, a bell wire) has been dis-

sipated, even if resting against a plastered wall, where there has been any

material damage done to surrounding objects.

Of course, it is readily understood that such an explosion cannot take place

in a confined space without the rupture of the walls (the wire cannot be

boarded over); but in every case that I have found recorded this dissipation

takes place just as gunpowder burns when spread on a board. The objects

against which the conductor rests may be stained, but they are not shattered,

I would therefore make clear this distinction between the action of electri-

cal energy when dissipated on the surface of a large conductor and when dis-

sipated on the surface of a comparatively small or easily dissipated conductor.

When dissipated on the surface of a large conductor, a conductor so strong

as to resist the explosive effect, - damage results to objects around. When

dissipated on the surface of a small conductor, the conductor goes, but the

other objects around are saved

A Typical Case of the Action of a Small Conductor.

Franklin, in a letter to Collinson read before the London Royal Society,

Dec. 18, 1755, describing the partial destruction by lightning of a church-tower

at Newbury, Mass., wrote, “Near the bell was fixed an tron hammer to strike

the hours; and from the tail of the hammer a wire went down through a small

gimlet-hole in the floor that the bell stood upon, and through a second floor in

like manner; then horizontally under and near the plastered ceiling of that

second floor, till it came near a plastered wall; then down by the side of that

wall to a clock, which stood about twenty feet below the bell. The wire was

not bigger than a common knitting needle. The spire was split all to pieces

by the lightning, and the parts flung in all directions over the square in which

the church stood, so that nothing remained above the bell. The lightring

passed between the hammer and the clock in the above-mentioned wire,

without hurting either of the floors, or having any effect upon them (except

making the gimlet-holes, through which the wire passed, a little bigger), and

without hurting the plastered wall, or any part of the building, so far as the

aforesaid wire and the pendulum-wire of the clock extended; which latter

wire was about the thickness of a goose-quill. From the end of the pendu-

lum, down quite to the ground, the building was exceedingly rent and dam-

aged.... No part of the aforementioned long, small wire, between the clock

and the hammer, could be found, except about two inches that hung to the

tail of the hammer, and about as much that was fastened to the clock; the

rest being exploded, and its particles dissipated in smoke and air, as gun-

powder is by common fire, and had only left a black smutty track on the plas-

tering, three or four inches broad, darkest in the middle, and fainter towards

the edges, all along the ceiling, under which it passed, and down the wall."

One hundred feet of the Hodges Patent Lightning Dispeller (made under

patents of N. D. C. Hodges, Editor of Science) will be mailed, postpaid, to any

address, on receipt of five dollars ($5).

Correspondence solicited. Agents wanted.


874 Broadway, New York City.



Electrical Engineer.

"The book is good, thoroughly good, and will long remain the best accessible elementary ethnography

Most people interested in Electricity Comparative Philology of the Old and New in our language."-The Christian Union.


If you do not, now is a good time to

Worlds in its Relation to Archaic
Speech. By R. P. GREG, Esq., F.S.A.,

"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.

It is published every Wednesday.

With an introduction on Race and Language, giving a résumé of the opinions of many of the principal writers on those subjects, accompanied by copious vocabularies and numerous tables of comparison for similar words and their cognate forms as for most of the chief families of languages, both ancient

"A useful and really interesting work, which deserves to be widely read and studied both in Europe

Subscription, $3.00 per year.
You can try it three months for fifty and modern, conveniently arranged for purposes of and America."--Brighton (Eng.) Herald.


An immense number of words are given, and especially for Turanian (including Chinese, Accadian and Egyptian), as well as for African and American ones.

"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.

The general results tend to show that there still exists in most languages, whether dead or living, a certain element of what may be called an Archaic

Residuum, more or less common to all.



"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.

Probably you take

The Electrical Engineer, New York, N. Y. Every reader of "Science" should subscribe for the

203 Broadway,


[ocr errors]



Architectural publication in the country. Interesting articles on architecture. Sanitation, Archæology, Decoration, etc., by the ablest writers. Richly illustrated Issued weekly. Send stamp for specimen copy to the publishers,

[ocr errors]

Ticknor & Co., 211 Tremont St., Boston. "Extremely useful to beginners and collectors for the region it covers."-Wm. H. Dall.


By AUSTIN C. APGAR. This work contains a key to all the genera, a glossary of Molluscan terms. descriptions 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.



South to Cape Hatteras.

1893 Catalogue

of Books on Building,
Painting, and Decorating,
also Catalogue of Draw
ing Instruments and Ma-
terials, sent free on appli-
cation to


For use in Colleges and Normal Schools. Price 50 cents
Sent free by post by

N. D C. HODGES, 874 Broadway, N. Y.


Imp. 8vo, Cloth, 430 pp. By Kegan Paul, Trench,
Trübner & Co., London. Price, 31s. 6d.
(less discount.)


Newspaper Clippings. 25,000 in Stock.
What do you want? Let us know.
can supply you. The Clemens News
Agency, Box 2329, San Francisco, Cal.

"A masterly discussion, and an example of the successful education of the powers of observation." -Philadelphia Ledger.

Price, postpaid, $2.



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

ly Index of the Periodical Literature of the World.

$1.00 per year.

Chicago, Washington, London, Paris.



Publishers, Importers, Booksellers.

We make a specialty of technical works in all branches of science, and in all languages.

Subscriptions taken for all American and foreign
scientific periodicals.

Our Paris and London branches enable us to im-
port at shortest notice and lowest prices. REPORTS
REPORTS, etc. Correspondence solicited.

All books reviewed in SCIENCE can be ordered

from us.

GERMANIA A monthly magazine for the study

of the German language and literature. is highly recommended by college professors and the press as "the best effort yet made to assist the student of German, and to interest him in his pursuit." Its BEGINNERS' CORNER furnishes every year a complete and interesting course in German grammar. $2 a year. Single copies 20 cents. P. O. Box 151, Manchester, N. H.

The Boston Medical and

Surgical Journal.

[blocks in formation]


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.

DAMRELL & UPHAM, 283 Washington Street, Boston, Mass.

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

"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.


This book is the result of an attempt to collect the scattered notices of fossil resins, exclusive of those on amber. The work is of interest also on account of descriptions given of the insects found embedded in these longpreserved exudations from early vegetation. By CLARENCE LOWN and HENRY BOOTH 12°. $1.


By DANIEL S. TROY. This contains a discussion of the reasons for their action and of the phenomena presented in Crookes' tubes.

Price, postpaid, 50 cents.


874 Broadway, New York. BUSINESS OPPORTUNITY.

There is an opening for a young man to open a New York office of the American Lightning Protection Co., operating under my patents. But little capital will be re




NEW YORK, JULY 7, 1893.


MOST of the text-books on the subject of chemistry in use at the present time still recognize but one compound of hydrogen and nitrogen, viz., ammonia. There are, however, now known to science, several compounds of these two elements. Of these the most important are ammonia, NH,; hydrazoic acid, HN,; and hydrazine, N,H1. There is a remarkable difference in the properties of the first two substances. Ammonia, the volatile alkali, has very strong basic properties, uniting directly with acids to form the ammonium salts. Only with the strongest basic elements does it act like an acid, forming sodium amide, NaNH,, with sodium, and potassium amide, KNH,, with potassium.

Hydrazoic acid, on the contrary, is a comparatively strong acid. Being a binary compound of hydrogen and nitrogen, it might well be called hydronitric acid, after the analogy of hydrochloric acid, hydrobromic acid, etc. Its structural formula is represented thus:

[merged small][merged small][ocr errors][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small]


NH,, N,H,, NH, NH, NgHs, and HN.. Heretofore hydrazoic acid and its derivatives have been made only by reactions' of organic chemistry; but within the past few months a method has been devised by Wislecenus' by which the acid is made entirely from inorganic substances. This is done by first treating molten metallic sodium (or potassium) with dry ammonia gas, and then treating the sodium amide thus formed

1 Berichte der deutsch. Chem. Gesellschaft (Curtius), xxiii., 3023; xxiv., 3345. Ibid (Noeting and Grandmongin), xxiv., 2546.

2 Ibid, xxv., 2084.

with dry nitrous oxide. The sodium salt of hydrazoic acid is thus formed; and, by treating this with dilute sulphuric acid, the hydrazoic acid itself is liberated, and may then be distilled off with water, thus giving a dilute aqueous solution.

Wislecenus performed the operation in a small porcelain boat within a glass tube. The porcelain is strongly attacked by the sodium compounds, and the yield of hydrazoic acid which Wislecenus obtained was nearly 50 per cent of the theoretical amount, and, besides, only a small quantity of the acid (about one-half a gramme) could be made at a time.

These objections to the apparatus used by Wislecenus induced the author to seek for a better form of apparatus with which to prepare the acid.

A cylindrical copper air-bath was selected, which was provided with two mica windows placed opposite each other, through which any operation that was carried on within the bath could be easily observed. The bath was about fifteen centimetres from top to bottom and of about an equal diameter. The cover was of heavy asbestos board. In the centre of this a large circular opening was made, through which a glass beaker of 750 cubic centimetres capacity was inserted into the bath until its rim rested upon the asbestos board, the bottom of the beaker not being allowed to touch the bottom of the bath. A small quantity of clean sand was placed in the bottom of the beaker, and upon this a small iron sand-bath, hemispherical in shape, and having a capacity of 100 cubic centimetres. The mouth of the beaker was closed with a large flat cork, provided with three holes. Through the central hole passes a glass tube which reaches a little way into the iron dish, and through which the gases are conducted into the apparatus. The second hole carries a short exit tube, and the third a thermometer.

Neither the metallic sodium nor the compounds formed have any action upon the iron dish, and the reactions which take place in the dish can be readily observed through the mica windows of the air-bath and the glass beaker.

The ammonia gas was obtained by gently heating on a waterbath a flask containing strong ammonia water, and the nitrous oxide by the decomposition of ammonium nitrate by heat. The gases were dried as directed by Wislecenus, by passing them over soda-lime and solid potassium hydroxide.

To perform the operation 25 grammes of metallic sodium were placed in the iron dish, the temperature of the bath raised to 300° - 360° C., and dry ammonia gas conducted in and delivered just above the surface of the molten sodium. The specific gravity of sodium being less than that of the amide formed, the metal floats on the surface until the action is finished. The reaction is represented by the equation:—

[merged small][merged small][merged small][merged small][merged small][ocr errors][merged small]

solved in 500 cubic centimetres of water, and then dilute sulphuric acid added till the hydrazoic acid was liberated. The solution was then distilled till the distillate ceased to give a precipitate with silver nitrate.

The distillate was then diluted to a definite volume and its strength determined by titration with standard ammonia solution. The yield of the acid was 87 per cent of the theoretical, 500 cubic centimetres of nearly 4 per cent solution being obtained.

A part of the acid solution was neutralized with potassium carbonate, and evaporated to crystallization. Beautiful, tabular, transparent crystals of the potassium salt, KN,, were formed.

The salts of hydrazoic acid, excepting the salts of the alkali metals and the metals of the alkaline earths, are explosive. In some respects the acid resembles hydrochloric acid. With soluble silver salts a white precipitate, AgN,, is formed. Lead acts similarly. These salts explode very viole when heated.


The most remarkable property of hydrazoic acid and its soluble salts is their physiological action. In this respect they resemble the nitrite of amyl, C, H11NO2, having a marked influence upon the action of the heart. The author found by experiment that one-tenth of a grain of the potassium salt, KN,, dissolved upon the tongue (the resulting solution not being swallowed, but ejected from the mouth) was sufficient to increase the pulse from 96 beats per minute to 153. This required only five minutes' time after the dose was taken. This rate of heart-beat is not sustained, however. A sudden and rapid reduction takes place, and ten minutes after the dose was taken the heart was giving 60 feeble beats per minute, making a total variation of 97 beats per minute. Considering the fact that this effect was produced by the small quantity of the substance which was absorbed by the mucous membrane of the tongue, this property is certainly remarkable. The vapors of the hydrazoic acid produce similar effects when inhaled.

The laboratory work reported in this article was performed in the chemical laboratory of Cornell University; and the author wishes to acknowledge that the success of the work was largely due to the aid and direction given by Dr. W. R. Orndorff. Thanks are also due him for his kindness in reading and correcting the manuscript.



THERE has been very recently published in the Transactions of the Royal Irish Academy (Vol. XXX., Part III., pp 109-230, Plates vii. to xvii.) the long-delayed work of Professor W. N. Parker of the University College, at Cardiff, Wales, "On the Anatomy and Physiology of Protopterus annectens." Through the courtesy of its author, a reprint of that most valuable quarto is now before me, and it is my wish to write a brief notice here in regard to it. The elaborate manner in which the Transactions of the Academy are published is too well know to require remark, but in the present instance it is impossible to pass this work without a word upon the truly superb plates that illustrate it. These, some ten in number, were chromo-lithographed by Professor Parker's younger brother, M. P. Parker, and printed by West, Newman. They present us with much of the anatomy and histology of Protopterus, and are throughout perfect masterpieces of the kind, and of the very highest order of merit.

As is well known, this genus formerly was written Lepidosiren, the South American species being L. paradoxu, and the African one L. annectens,' and among the first to pay any attention to it, of a reliable nature, was Sir Richard Owen, who, in 1839-1841, 1 Dr. Günther classifies them as follows:

Suborder III.

1. Sirenida
2. Ctenododi-

3 Phancro-

And he remarks that "Two species are known, L. paradoxa, from the system of the river Amazon, and L. (Protopterus) annectens, which abounds in many localities of the west coast of Africa, is spread over the whole of tropical Africa, and in many districts of the central parts forms a regular article of diet."

ORDER II.- Ganoidei Dipnol.


published his " Description of Lepidosiren annectens" in the Transactions of the Linnæan Society of London (Vol XVIII.), since which time naturalists have never ceased to furnish various accounts of the biology of this extremely important form, but usually based, as Professor Parker remarks, upon badly preserved material. Our present author was far more fortunate as he had perfectly fresh specimens to work upon. Of these he has said in his Introduction," that "All my material, with the exception of two specimens, purchased last autumn, were placed at my disposal by Professor Wiedersheim. These were received alive direct from the neighborhood of the Gambia, and to Dr. J. Beard is due the credit of having arranged for their transport. While in the torpid condition about one hundred specimens had been dug out, each surrounded by a clod of earth, and the clods were then packed together in open crates. In this manner they travelled without harm, nearly all of them being alive and in a healthy condition on their arrival in Freiburg. On being removed from the clods, they were, by the kind permission of Professor Hildebrandt, placed in a large wire cage, sunk beneath the water in a basin used for the culture of water plants in one of the hot-houses of the Botanical Gardens, in which a constant temperature of 22.5° C. was maintained." . . . . Protopterus lives probably to a great age, and this supposition is supported by the somewhat incredible statement of the natives mentioned by Stuhlmann, that some specimens reach a length of six feet. From the observations of Hyrtl and Bischoff, it appears that Lepidosiren also attains a large size, reaching, at any rate, three feet in length" (p 112).


Genera. (Lepid siren, incl. Protopterus Ceratodus. (Two extinct genera, Dipterus and Heliodus. Extinct Phancropleuron.


It was found that Protopterus grows very rapidly, has great vitality, and, although able to sustain fasts, is exceedingly voracious, devouring all the abundant snails, earth-worms, and small fish given them, and then killing and eating each other, making it difficult in the extreme to preserve the specimens.

Protopterus is most active at night, and appears to keep mostly to the shallow water, where they move deliberately about on the bottom, alternately using the peculiar limbs of either side, though their movements do not seem to be guided by any strict regularity. "Gray has compared these movements with those of a Triton, and several other observers bave noticed them. The powerful tail forms a most efficient organ for swimming rapidly through the water."

"It is well known that Protopterus comes to the surface to breathe at short intervals, and thus it is evident that the lungs perform an important, if not the chief, part in respiration during the active life of the animal. The air passes out again through the opercular aperture, and the movements of the operculum itself indicate the fact that bronchial as well as pulmonary respiration takes place."

Externally, the sexes present no characters whatever distinguishing them apart, and even in immature specimens it is difficult to tell ovary from testis.

In the present brief notice it will be impossible for us to even abstract the positive advances Professor Parker has made for us in our knowledge of both the anatomy and physiology of this instructive Dipnoan. He sums up handsomely on page 213, under his "General Abstract, Summary of Chief Resu ts, and Conclusions."

His researches convince him that, although many points of resemblance exist between Protopterus and certain Elasmobranchs and Ganoids on the one hand, and on the other to some of the lower Amphibians, it exhibits numerous distinctive characters of its own, both primitive and specialized, and so, together with Lepidosiren and Ceratodus, must be placed at a great distance from either class. Further, he believes that the Dipnoi, as a group, should not be retained among the fishes, still less among the Amphibia.

2 To those less familiar with the habits of this extraordinary fish, I would say that the species averages about four feet in length, and is an inhabitant of the Gambia River in Africa. They bury themselves in the mud during the dry season, making a kind of nest in which they pass a period of torpidity. Here they may remain for the best part of the year, but on the return of the wet season resume again their aquatic mode of life.

In 1889, it will be remembered, Stuhlmann also gave an interesting account of Pro:opterus, published in German. (Berlin.)

[ocr errors]

Highly specialized in some respects, in both Protopterus and Lepidosiren, this specialization is largely due to a change of habit, and that, undoudtedly, these two types are, genericly, very distinct.

In conclusion, I may simply add that this classical work will, in the future, prove to be one of the very greatest value to all students of the morphology of the Amphibia and of Pisces, as it will be indispensible to the general biologist


BY E. H. S. BAILEY, UNIVERSITY OF KANSAS, LAWRENCE, KAN. A SEVERE and fatal cyclone visited a small area of country in the Kaw ralley, in Jefferson County, on June 21, at about six o'clock in the evening, and the peculiar topography of the country gave an opportunity to make some observations that may be of scientific interest. The valley at this point is about two miles in width, the river running nearly east. On the south side it is bounded by bluffs about a hundred feet in height, and on the north side there is a strip of level meadow, something over a mile in width, before one reaches the bluffs, which are of about the same height as those on the south side.

The general trend of the broad valley is east, but at a point a mile or so beyond where the cyclone lifted the river runs toward the southeast for perhaps a mile. On the particular afternoon in question the weather had been extremely hot and sultry, the mercury ranging between 90° and 95° F. The weather had been warm and dry, with only one local shower for about two weeks. About two hours before the cyclone burst upon the valley there was a gathering of clouds in the northwest, with thunder and lightning. A short time before the storm burst an ominous stillness was noted, and a sudden darkening of the sky. During the heaviest of the storm a peculiar green tint of the sky was noticed in the locality.

As the storm came from the west, it seemed to settle near the ground at the base of the bluff, and, wherever the bluff was not broken by lateral valleys, its path was about one-half on the side of the hill and the other half on the sloping meadow to the south. Wherever the cyclone crossed the course of lateral ravines, even if they were quite narrow, it dipped down into them and destroyed trees and buildings. It was not swerved from its general eastward course even at one point where a broader valley joined that of the Kaw. At this point, as the country was heavily timbered, there was a special opportunity to observe the action of the wind. Elm and walnut trees, two or three feet in diameter, were either torn up by the roots, laid prostrate, or twisted off fifteen or twenty feet from the ground. Here the track of the cyclone, where it did appreciable damage, was a little less than 600 yards in width. There were, occasionally, wrecked chimneys and slightly injured roofs on the outer edges of this path. All along the course of the storm the debris was deposited in the peculiar way that is characteristic of these furious whirlwinds. The material north of the centre of the track was deposited in lines from northwest to southeast, and that on the south side of the centre in lines running from southwest to northeast. In the centre of the track there was a tendency to distribute the material in an east and west direction. A line of telephone poles on the south side were laid in parallel lines, thus, /////. Fields of grass and wheat were beaten to the ground and the stalks laid in the directions above noted: W. →E. The wires of the telephone line and of the barb-wire fence were lifted into the tree-tops about fifty feet north of their original position. There was a little debris deposited on the west side of some of the buildings demolished, but most of it was carried along the track and thoroughly pulverized. Strong, new farm wagons were wrenched to pieces, and the spokes were even broken off near the hub, before they were deposited half a mile away.

The terrible force of the wind could be seen in the beheading of the wheat, the uncovering of potatoes in the hills, the transportation of grave-stones 300 yards, and the picking of all the feathers from the chickens

One of the most interesting effects that was noticed was upon

the trees that were left standing or laid prostrate and bereft of every vestige of foliage and of nearly all the bark. All the wood on the west side of these trees, often being exposed by having the bark torn off, was roughened as if by a sand blast; while that on the east side was smooth. This roughness was uniform, showing that it was not produced by occasional missiles hurled through the air. This roughening, if not produced by the actual friction of the air, must have been produced by the sand and gravel in the air, or by the rain that beat against the surface.

Some who witnessed the storm saw the clouds of dust that accompanied the wind, so the sand-blast theory is no doubt the correct explanation.

The most serious work of destruction was accomplished just before the cyclone lifted. Here the valley broadened out towards the north, and the bluff for a distance of a mile or more disappeared. With one last sweeping blow the storm lifted, and the only other evidence of its work was a partially demolished barn. Just at the point where the intensity seemed concentrated, the path was much narrower than farther west. The strip of land devastated was about five miles in length. From the manner in which it followed the base of the bluff, one would infer that had it not been for this obstruction the storm would have passed off towards the northeast instead of pursuing, as it did, a direction a little south of east.



In the waters of Wisconsin and in the adjacent lakes are found the following twenty-one species of free-swimming copepods : Diaptomus sanguineus, Forbes; D. leptopus, Forbes; D. fallidus, Herrick; D. sicilis, Forbes; D. ashlandi sp. nov; D. minutus, Lillj.; D. oregonensis, Lillj.; Epischura lacustris, Forbes; Limnocalanus macrurus, Sars; Cyclops americanus, sp. nov.; C. brevispinosus, Herrick; C. pulchellus, Koch; C. navus, Herrick; C. parcus, Herrick; C. leucarti, Sars; C. signatus, Koch; C. modestus, Herrick; C. fluviatilis, Herrick; C. serrulatus, Fischer; C. phaleratus, Koch; C fimbriatus. Fischer.

Although two of these, D. ashlandi and C. americanus, are new species, it is not probable that they are peculiar to the Wisconsin fauna. The copepods of America have thus far received very little attention, the only important publications on the subject being by three men, Professor Cragin, Professor Herrick and Professor Forbes. If more were known of our copepods it is probable that it would be found that there are few local differences in the faunæ of our northern States. The copepods are readily transported from one body of water to another and, without change of structure, seem to endure great changes in their environment In fact, half of our species of cyclops are not only widely distributed in America, but are identical with those of Europe. Those that may be considered distinctly American are closely allied to well-known European forms.

C. leucarti is found in nearly all parts of the world where collections have been made and, so far as can be inferred from the published descriptions, varies but little, even in the minute details of its structure.

[blocks in formation]
« PrethodnaNastavi »