Lapas attēli
PDF
ePub

original surface there was found the principal bones could ever have been distributed as this part of the skeleton, considerably scattered

skeleton was.

The bones must, perhaps withabout, but with the skull nearly intact and out exception, have been held together by the with unbroken tusks. The bones lay on a bed ligaments and probably much of the flesh reof clay, broken slate, gravel and water-worn mained. At this moment the river rose and pebbles. This was probed to a depth of ten swept the flood plain, carrying the cadaver feet without finding bottom. The right fore over the potholes. First the right leg became leg of the skeleton was missing, but was later detached and was swept into the upper one of found in another pothole 60 feet farther up the two holes; then the remainder of the body stream and at least 25 feet higher. Hall was carried on and dropped into the second thought that the potholes were of glacial or hole. Here the swirling waters either at once preglacial origin, but I am assured by Pro- or during subsequent floods scattered the fessor Fairchild that they have been drilled skeleton somewhat. As time went on, all sorts since the Wisconsin ice sheet abandoned that of materials were borne into the potholes vicinity. When the ice began to withdraw, during freshets. Possibly some trees growing the region was depressed about 350 feet below on their margins fell into them. At any rate, its present level, as a result of which the site they finally becanie filled up. of Cohoes was covered with a thick deposit It appears quite certain that when the of sand and clay. As the land slowly emerged, Cohoes mastodon was buried the deposition of the old Mohawk River (Fairchild's Iromo- marine sediments in the Champlain and the hawk) cut through the estuary deposits and upper St. Lawrence valleys had largely taken finally reached the underlying Hudson slates. place and the Champlain epoch, about the Then under the action of strong currents the last leaf of the last chapter of the Pleistocene, drilling of the potholes began. The land had had nearly ended. Did mastodons end their then risen, as Professor Fairchild writes, at career at this stage of geological history or least 150 feet. At the same time the stream did they continue on into the Recent epoch? bed was being worn down into the rock and It may be impossible to determine this. If the falls were moving up stream past the they did continue to exist, it might be suppotholes. When the mastodon entered the posed that remains of them might be found pothole this had long before ceased being cut; in deposits of marl and muck overlying the for, as already stated, it had became filled to Champlain deposits along Lake Champlain, a depth of at least 10 feet with rock débris. and the St. Lawrence and Ottawa rivers; but It had quite certainly been abandoned by the the writer has not learned of any such cases. river waters, except at times of food. How At any rate, the close of the Pleistocene or now did the mastodon get into that hole? the beginning of the Recent became an inHall concluded that it had been frozen up in salubrious time for this species, a mighty race the glacial ice and had been dropped part in which can be traced back possibly to the one pothole, part in the other. But when Pliocene and which had weathered the vicissithose potholes were ready for occupation as a tudes of four or five glacial periods. At aptomb for the mastodon, there was no part of proximately the same time there perished two the general glacial sheet from which the species of elephants, the giant beaver (Castocadaver could have reached Cohoes.

roides), the moose (Cervalces), and perhaps recently dead body it might indeed have been other great animals.

0. P. HAY floated down the Mohawk; but the animal U. S. NATIONAL MUSEUM could as well have lived and died at Cohoes. We may fairly assume that it had

HUMAN FLYING cently died and was lying on the flood plain TO THE EDITOR OF SCIENCE: While engaged not far above the potholes. No disarticulated in some scientific research, my attention was

As a

re

we are

called to an editorial article with the above

KEEPING STEP caption, in the American Journal of Mining, TO THE EDITOR OF SCIENCE: Sound travels April 25, 1868, Vol. V., p. 264, which later about 1,060 feet per second at 0° C., or 265 feet became the well-known Engineering and Min- in one fourth second. The soldier next the ing Journal. A comparison of what is accom

drummer steps with the drumbeat, the soldier plished now with the scientific view of that 265 feet in the rear is one fourth second late day, a little over fifty years ago, may prove

and has his foot in the air when the foot of interesting to the readers of SCIENCE.

the front man is on the ground. This is be

cause they march at 120 steps per minute (2 In part, the article states:

steps per second), which gives one half a step Inventors have puzzled their minds for ages to in one fourth second. Hence the soldier who compass the problem of air navigation by machines hears the signal one fourth second late will or by flying men; and but little advance has been

fall one half step behind. I have seen this in made. It would of course be absurd to af.

columns turning into Victoria Street from firm that anything could not be done, in this age

Westminster Cathedral, at Lancaster Gate or of the world; but while this feat may be accom

Holloway Road, on Salisbury Plain, etc. plished to an extent “enough to say so,'

When tired out or on rough roads soldiers incredulous of any practical benefit of the thing

left to themselves do not keep step; but it is to man. The force which a man is able to expend in rapid ascension of heights, even 'with

a remarkable fact that the only time they keep the firm earth under his feet, is very small; and perfect step is when they are without sound we have never seen any principle elucidated which signals. If the drum begins they lose perfect was able by apparatus to increase his power or step at once and the feet are seen to strike the lessen his gravity in proportion to it.

ground in receding waves as the sound passes The balloon remains; but that, if used, presents down the line. If the drum stops, the men in such a surface to the atmosphere that it can not

two or three seconds get into perfect step again, be accurately guided without, by means of steam

and go with a sway and swing absent at other boilers or other weighty machinery, storing up

times. The French term it rapport or esprit power for propulsion, in a manner of itself too cumbrous and heavy for successful navigation.

du corps. Is there a mutual subconscious force So that, whether it is for his own personal flight passing between the men? In a short brochure through the air or the management of a great at

of experiments in such matters to be found at mospheric ship, man seems to be hemmed in on public libraries I have suggested an explanaevery side by almost insuperable natural difficul

tion. Is it the right one? I should be glad to ties. And besides, even were all this obviated, hear from American observers of the phewho would run the risk of accidents at a great

WALTER MOORE COLEMAN, height above the earth, beyond the reach of help Fellow of the Physical Society of London but not of gravitation It is an interesting prob- HARSTON, CAMBRIDGE, ENGLAND lem, and may result in pretty scientific toys; but for real helpfulness to humanity we see but little in

QUOTATIONS Aeronautics.

THE ORGANIZATION OF RESEARCH IN

GREAT BRITAIN Taking the vast change that has been worked out in the life time of many of us,

In a paper on the state organization of redoes it not afford encouragement to our young

search, read at a recent meeting of the Royal

Society of Arts, Sir Frank Heath, K.C.B., people to endeavor to solve the many problems lying before them, ere the next fifty years

Secretary of the Department of Scientific and shall pass ?

Industrial Research, succeeded in compressing M. E. WADSWORTH,

into a few pages a lucid amount of the work Dean Emeritus

of his department. His characterization of SCHOOL OF MINES,

research in general is, so far as it goes, exUNIVERSITY OF PITTSBURGH

cellent, and ought to be taken to heart by the

nomena.

public, but the treatment of a vast and com- penalty of a hundred years' sloth. It is too plex subject which approves itself to one late to build from the ground on the German thoughtful man can not be expected to satisfy lel, but we need not pretend that we have all his readers. If, then, we dwell upon points discovered for ourselves a better model, but of disagreement, we are not the less conscious should, with humble and contrite hearts, try that Sir Frank's paper compares favorably gradually to improve our temporary strucwith the lucubrations of most administrators. ture into something like a real university sys

In the earlier part of his paper he empha- tem, keeping it free from such defects and sized the novelty of the departure made by the abuses as in Germany that system revealed government in 1915, and, without the assertion in practise; of these the worst was the prostiin so many words, rather implied that our tution of scientific appointments and scholarly government has handled the problem of na- reputations to the uses of political propaganda. tional research with more courage and on more - British Medical Journal. satisfactory lines than did that of the Germans. While we agree that the course fol

SCIENTIFIC BOOKS lowed here since 1915 was the best in the circumstances, we are emphatically of opinion

Bastardierung als Ursache der Apogamie im that this is only true in consequence of past

Pflanzenreich. Eine Hypothese zur experierrors; that the idea inspiring the memoran

menteller Vererbungs- und Abstammungsdum of v. Humboldt, quoted by Sir Frank

lehre. By ALFRED Ernst, professor of botHeath, is correct, and that the system of the any in Zürich. Jena, Fischer. 1918. Pp. German government was in principle thor

650, with 172 figures and 2 plates. oughly sound.

The ultimate practical aim of the theory of The German ruling caste appreciated the

mutation is avowedly to discover the means of importance of scientific knowledge a century producing new qualities in plants and animals before ours, and conceived that the best way at will and in arbitrarily chosen directions. to foster research was to create a number of Some investigators assume that one of the adequately equipped university departments; chief causes of mutation is to be looked for they believed that the multiplication of oppor- in crossing, whereas others think that crosses tunities for disinterested investigation would are far too rare in nature to have had any lead to the production of trained minds appreciable effect in the production of species, capable, in Sir Frank Heath's words, " of ex- except for the polymorphous genera. Obtending the powers and capacities of man in viously the best way to decide between these relation to the world in which he lives.They two opinions is to study the influence of hy. had their reward; all that scientific ingenuity bridizing on the origin of a new character. and foresight could do to safeguard the Teu- The author of this book has attacked this tonic hegemony was done there was no need problem from a special side, proposing to try of hasty improvisations. The German state to induce a definite character, viz., apogamy, system has perished in scenes of death and or the production of seeds and spores without disaster, but of the many crimes and blunders fecundation, by means of artificial crosses. committed by its makers, the neglect of sci- The book does not bring any new results, but ence is not one. In this country, generations a collection and discussion of the facts, availof neglect have compelled us to adopt in our able for the choice of the material and the hour of need an expedient which would not method of experimentation to be used. have found a single defender if proposed as a From this point of view it may be comnormal method of evolution. The courage of mended to the student of rich questions. It the government in 1915, which Sir Frank gives a full description of all known cases of Heath extols, was the courage of despair; we apogamy, including algæ and fungi on one could not then, we can not now, escape the hand, Marsilia, Antennaria, Alchemilla and Hieracium on the other. The doubling of But it seems highly desirable that the exchromosomes, the terminology of partheno- perimental trials should be made, the more genesis, the nucellar embryos, the lessened while in any case the gain for the theory of fertility and many other effects of hybridizing, mutation must be expected to be of the highas well as those of vegetative propagation are est importance. extensively dealt with. From this survey the

HUGO DE VRIES author concludes that Chara crinita seems to

LUNTEREN,

HOLLAND afford the best material for further studies and gives an ample review of the mode of PRELIMINARY REPORT OF EXPERIpropagation of this algą.

MENTS ON THE ACTION OF DIIt is a dioecious plant, which has a par

CHLOROETHYLSULFIDE thenogenetic variety. The latter has been

(MUSTARD GAS) ON described by Alexander Braun as early as

THE CELLS OF

MARINE OR1856 and since by numerous authors. The

GANISMS species is rather rare; in some stations it is found without the variety but in the larger

The toxic action of a sample of “mustard number of localities only the apogamous form

gas

sent us by Major H. C. Bradley, of the occurs. In some, however, both grow together,

Chemical Warfare Service, has been investiindicating the possibility of a repeated origin gated on a number of typical marine organof the variety from the dioecious type. More

isms, including various swimming larvæ (seaover it is shown that the differences between

urchin, starfish, squid, the annelids Nereis the two types are of such a kind, that they

and Arenicola), the developing eggs of seacan not have originated slowly and gradually

urchin and star-fish, the spermatozoa of seabut must be assumed to be due to a sudden urchin and starfish, and young and adult fish change (p. 104). This is the well-known way

(Fundulus). The most satisfactory objects for in which in other cases mutations are seen

experimentation have proved to be the developto arise. The probable difficulties of the in- ing eggs of the starfish (Asterias forbesii), tended investigation are then amply discussed.

and most of our work has been carried out To these the reviewer might add the objection with this material. Changes in the rate and that it is a species which has already produced character of cleavage in the eggs after treatan apogamous form, and probably more than ment with “mustard,” the production of abonce and which therefore may be expected to

normalities of form and structure in the larvæ, repeat the mutation from time to time, even and the degree of ciliary activity, furnish a without the aid of experimental interference. very delicate index of toxic action. Valuable Furthermore, the experience with the evening information has also been obtained with Arenprimrose has shown that mutations occur in icola larvæ and with small fish (Fundulus). crossed progeny as well as in pure lines and In the experiments with fertilized starfish the research of Baur on Antirhinum and of eggs we have investigated the influence of Morgan on Drosophila have amply confirmed solutions of the “mustard gas” in sea-water this result. Among hybrid progenies they upon the cleavage and early development (up seem to be more numerous, but only in con- to the gastrula stage). The procedure chiefly sequence of the fact that such cultures usually employed was as follows: A small quantity of embrace many thousands of individuals more the “mustard gas” (ca. 5 grams) was shaken than are kept in the pure stocks. The same vigorously with one liter of sea-water in a will be the case in the cultures of chara crinita

1 This preliminary report in its present form and the expected occurrence of apogamous was sent to the Medical Section, Chemical Warfare mutations in hybrid families can, therefore, Service, Septe

Service, September, 1918. A more detailed acnot be regarded as a proof of their origin by count of these experiments will be published in means of hybridization.

the near future.

2-liter glass-stoppered bottle. After the finely solid at this temperature), and the cold saturdivided undissolved oil had settled, the clear ated solution thus obtained was kept at 0° liquid from the middle of the solution was (surrounded by ice in the refrigerator). The drawn off, and the action of this saturated toxic action of a portion of the solution kept solution upon the recently fertilized mature thus cold and brought to room temperature eggs was tested, using varying dilutions (e. g., immediately before adding the eggs was com1/2, 1/4, 1/8, 1/16 saturated) and varying pared with that of portions which were times of exposure (from one fourth minute to brought to room temperature and allowed to an hour or more). The eggs were exposed to stand for varying times (e. g., 1/4 hour, 1/2 the solutions in glass-stoppered bottles, and at hour, 3 hours, 24 hours) before using. In all intervals portions were transferred by pipette cases solutions which were kept cold until just to dishes of normal sea-water; this water was before using were decidedly the most toxic, changed when the eggs had settled. The sub- 15 minutes' exposure to room temperature resequent course of cleavage and development, duces toxicity by about one half, and 30 minas compared with that of untreated “control” utes by two thirds or three quarters. The eggs, was carefully studied.

decline in toxicity is thus at first rapid, then The toxicity of “mustard” solutions pre- more gradual; the same is true of the propared in the above manner is not constant but duction of acid as shown by titration. The decreases with standing, and the more rapidly reaction is apparently mono-molecular. the higher the temperature. Solutions made Our experiments favor the following conat room temperature (20–24°) always prove ception of the mode of action of “mustard” strongly toxic if used immediately after prep- upon the living cell. The undecomposed aration; if used later the toxic action is less “mustard gas" is slightly soluble in water marked, the decline of toxicity being rapid in (according to our titrations of completely the first hour and more gradual later. This hydrolyzed solution to the extent of ca. .05 per decline is due to the progressive hydrolysis of cent.). This dissolved “mustard” readily the “mustard,” which breaks down rapidly in penetrates the cell, presumably because of its aqueous solution, yielding HCl and residual high lipoid-water partition-coefficient, and colcompounds of low toxicity. The toxicity of a lects in relatively high concentration in the "mustard” solution two days old, in which the organic solvents of the protoplasm (cellacid freed is neutralized by NaOH, is not lipoids, fats, etc.). In this situation it serves more than one fiftieth of that of the freshly as a reservoir of toxic material which conprepared solution, as measured by the com- tinually enters solution in the aqueous phases parative times of exposure required to pro- of the protoplasm and is continually being duce a definite impairment of development or there decomposed. Since by its hydrolytic a definite proportion of dead eggs in a given decomposition it yields acid, the dissolved time. The attenuation of toxicity, as thus “mustard” acts destructively on the protoshown by the physiological action of the solu- plasm as soon as the available buffer comtion, exhibits a general parallelism with the pounds (which normally prevent protoplasmic production of HCl, as measured by titration hyper-acidity) are exhausted. The destructive (with dibromocresolsulphonephthalein as in- action is thus due primarily to the HCl freed dicator). The essential toxic action is thus by hydrolysis. The other decomposition-proddue to the undecomposed "mustard” in the ucts are only slightly toxic; this we have solution. This conclusion was confirmed by shown experimentally by comparing the action experiments in which the hydrolysis of the of partially or wholly hydrolyzed solutions of compound was retarded by cold. The oil was the “mustard," from which the acid was reshaken with ice cold sea-water (below 3°), the moved by neutralization with NaOH, with solution was filtered free from the residual that of the unneutralized solution. The latundissolved crystals of “mustard” (which is ter solution is always by far the more toxic;

« iepriekšējāTurpināt »