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way comparable to the convincing evidence above adduced separating from the mass, and at the same time assuming concerning the heterogenetic origin of Monads from the a brown colour. This change was proceeding more rapidly transformation of Zooglæa masses-a transformation in at the edge of the mass; but further in, as may be seen which we have vegetal organisms giving rise to animal in the upper portion of the figure, the mass shows more organisms of a totally different kind, though between these of the appearance to be seen in Fig. 8. Although the germs two forms of life no relation of kinship has ever been seem to separate from the metamorphosed Zooglea mass admitted, or even suspected, by the great majority of as bodies of varying size, I think there can be no doubt that biologists.

some of the separate units subsequently increase distinctly in Origin of Fungus-germs from Masses of Zoogloea. It has seemed to me, as I have said, impossible to say from the mere microscopical characters of the masses of Zooglæa whether they are likely to yield Monads or Fungusgerms. It will be observed, however, that in the three cases to which I have just referred the masses giving rise to embryo Monads have all been small, and that they have tended to go through their metamorphoses with some rapidity.

It is certain, however, that the great majority of the larger Zooglæa masses tend rather to produce Fungusgerms of one or other kind, and to go through their changes at a slower rate. These statements may be illustrated by a record of the changes taking place in the larger Zooglæa masses that were found in great abundance in the pellicle forming on infusion A. These larger masses of Zooglæa, and also all the later changes which I am now about to

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Fig. 9.-Development of small brown Fungus-germs from a mass of Zoogica

(X 500). describe, were, however, wholly absent from the pellicle on infusion B, up to the eleventh day.'

Where the changes occur to which I would now direct attention the Zooglæa masses gradually become larger and much more refractive, while they also stain much more deeply with logwood, gentian violet, or other of the aniline dyes. At the same time the constituent bacteria, which are so very distinct in the early stages, seem to become enlarged and gradually more or less hidden as the molecular changes taking place in the mass increase. One of these aggregates in this refractive, glistening stage, which was found and photographed on the fifth day, is shown in Fig. 7 (x375).

The next stage of change is revealed by distinct indications of segmentation beginning to show themselves through the mass, such as may be seen in Fig. 8 (< 500), which represents a portion of a large Zooglæa mass that was found on the sixth day. This condition may persist for several days, but occasionally further changes occur rapidly, as may be seen by Fig. 9 (x 500), showing a portion of another large Zooglæa mass found on the seventh day, in which minute ovoid germs of different sizes are

i See note on p. 78.

Fig. 11.-A, Heterogenetic Fungus-germs ( X500): B, Acrospores produced

from the mycelium (x500).

but occasionally they do so, and two or three masses of mycelium to which they had given rise (also of a brown colour) were found on the eighth day. One of them had sent a hypha above the surface, and there produced a great number of ovoid acrospores having a bluish-black appearance. Some of the mycelium is shown in Fig. 10 (X125). while the acrospores are represented in Fig. 11, B (x500)

It will be noted that the acrospores are comparatively uni

enormous increase of knowledge, and the benefit which has form in size, and are wholly different from the extremely

accrued to the human race, from their studies, but should variable brown Fungus-germs produced from the Zooglæa

like to see a little more toleration displayed for those who masses.

prefer to work in a different way, and strive to find out What has just been illustrated is only one of the ways what goes on under more natural conditions—undeterred in which Fungus-germs are produced in the pellicle from

by the much talked of but much over-rated risk of “inZooglæa masses. Anyone working at this subject will have

fection." Assuredly, in the future, much of what is now no difficulty in recognising many other modes in which

ascribed to “infection " will be differently regarded as the they originate. Sometimes the germs separate from the

origin of species by heterogenesis becomes more and Zooglæa masses as colourless units, and then take on an

more known. almost black colour before they begin to germinate, as in the specimen shown in Fig. 12, which was taken on the

If such processes as have just been described are contwelfth day from another pellicle on a hay infusion.

tinually going on in nature, but are not to be met with in

the laboratories of bacteriologists, it should make us hesiI have frequently found that these heterogenetic Fungusgerms are small ovoid bodies with one, or sometimes two,

tate to repudiate a natural origin of living matter at the nuclear particles such as may be seen in this case, and

present day simply because undoubted proof of its occuralso in some of the small brown units shown in Fig. 9.

rence cannot be produced by laboratory experiments. If it It is interesting, moreover, to find that the immediate pro

occurred in the past the law of Continuity would lead us ducts of segmentation which are about to develop into

to expect that it has bee

continually occurring ever since,

and, as I said in my letter of November 10, if the origin flagellate Monads present, except for their spherical shape,

of living matter takes place by the generation in suitable very similar characters, as may be seen by reference to fluids of the minutest particles gradually appearing from Fig. 5, A. It seems to me impossible to doubt that we have in the

the region of the invisible, such a process may be occurring

everywhere in nature's laboratories, though altogether processes which I have just described definite instances of

beyond the ken of man.”

H. CHARLTON BASTIAN. heterogenesis. The fact of the individualisation and the segmentation of these Zooglæa masses cannot be denied. It is plain, indeed, that from such aggregates of bacteria,

The Temperature of Meteorites. by common consent regarded as belonging to the vegetal DURING the early part of the year 1901, when I was on kingdom, we have the production of typical animal the staff of the Elswick Works, it occurred to me that it organisms, and that, as I have said, no kinship between would be useful and interesting if a connection could be

made between the conditions of the flight of artillery shells and of meteorites. Later in the same year I made a preliminary mathematical investigation into the matter, and as a result a paper on the temperature of meteorites was sent in as an essay to compete for the Smith prizes at Cambridge. It was distinguished from other essays sent up in not receiving a prize.

It has since remained a strong wish on my part some day to work up the subject into a form fit for presentation to a scientific society, but the pressure of other matters has prevented this. In order, therefore, to preserve at least its outlines, I give here a brief exposition of the premises, the procedure, and the conclusions of the essay.

Ordinary ballistic tables contain a wealth of information as to the retardation experienced by projectiles of all sizes and of one general shape. The shape of the shell is well known. If the same rules can be made to fit the motion of meteorites it is clear that the velocity at any time can be obtained, and thence the loss of energy due to the obstruction caused by the air. This energy reappears as heat, sound, electrical energy, chemical energy, &c. Of these by far the most important is heat. Thus the conditions under which a meteorite “heats up can be ascer

tained, and if it be assumed that all the energy is so spent, Fig. 12. —Heterogenetic Fungus germs becoming black and germinating it is obvious that a superior limit to the resulting tempera(x 500).

ture may be obtained. One further point should, however,

be mentioned—a meteor which reaches the earth is called a bacteria and flagellate Monads has ever been recognised, or meteorite,' and the velocity necessary for this is such that eren suspected, by the great majority of biologists; and,

the time of passage through the material part of the earth's though it cannot be said that there is the same lack of

atmosphere is so short, say five seconds, that chemical burnkinship between bacteria and Moulds, it can certainly be ing will not, in general, introduce any sensible error. Such said that the majority of biologists have never suspected error as might be introduced would be of the opposite sense any such relation between these two forms of life as that to radiation losses, themselves small for much the same which has now been made known.

I care little what names may be given to the bacteria, Meteorites may be of almost any shape. I have only though I am certain that many different varieties are prone considered the shell shape, as it is the only one the flight of to form zooglæal aggregates, and to go through one or which has been thoroughly investigated by exhaustive other variety of such changes as have just been described. Being much interested with these processes that go on

experiment.

According to Ingall's “ Exterior Ballistics," the law of in nature, and under more or less natural conditions, I have the resistance of the air is a function of the velocity which, been familiar with such phenomena for more than a gener- for velocities above 1380 feet per second, is the velocity atron; but although they were made known so long ago squared. For meteoric problems, velocities less than this I am not aware that any bacteriologist in Europe, America are unimportant. Whether this simple law would hold or elsewhere has ever repeated my observations. Bacterio- good for velocities of, say, 20 miles a second, or even the logists to whom I have personally mentioned the subject 3 miles a second which the earth can impose, is not known, have, with only one exception, shown not the least desire but for lack of a better it has been necessary to employ it. to examine specimens or to follow up the inquiry. They The next difficulty, and of difficulties there is no small seem wedded to their strict laboratory methods, and seem- number, lies in the varying density of the air. A few ingly preler to have dealings with nothing but pure cultures thousand feet is the upward limit of ordinary projectiles. and sterilised media. I do not deny for a moment the Even for howitzer shell the correction for rarefaction is so

1 See Proceedings of the Royal Society, 1872, vol. xx. p. 239. slight that the simplest kind of correction is enough. For

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are

were

were

meteorites, however, more extended treatment is required. volcanoes. The results of such an investigation may be I have taken the resistance to be in direct proportion to briefly summarised as follows :-Had the earth no atmothe density of the air. To do even this requires a know- sphere all masses shot off vertically at 7 miles a second ledge of the density at all altitudes, and for this I have and over would fail to return. With the existing atmoassumed an isothermal distribution of temperature. The sphere the large meteorite would require a velocity of 13 theory of adiabatic distribution makes the atmosphere cease miles per second, and the “ twelve pound shell would at distances well within twilight and meteor phenomena, want a velocity of 78 miles per second. These velocities and is therefore of no use. Probably something between not without interest in view of the theory that these two would be most accurate, but its precise form is meteorites originated from terrestrial volcanoes. Śmaller not of great importance in this investigation owing to the velocities would suffice

the masses discharged very slight influence of the uppermost reaches of the air from high altitudes. Thus, from a height of 5 miles, on the motion of meteorites.

the velocity for the large iron meteorite would be only I now come to the meteorites themselves. Many sizes 81 miles per second, and for the “ twelve pound shell have been considered, but chiefly diameters of 0.10 inch only 18 miles a second. Further calculation shows that and 12.0 inches. I refer to these as the “ small and the with an initial velocity of 7 miles a second the large “ large” meteorites. When other sizes are mentioned meteorite would rise to only some 120 miles, and the their diameters are given. I have further taken two “twelve pound shell "to between 40 and 50 miles, and both materials, viz. iron and stone (trap rock), representing would then fall back to the earth. holosiderites and asiderites. The thermal constants for In conclusion, the result of the investigation may be said the materials are those found by Forbes.

to have created a strong presumption in favour of the I stated above the circumstances in which a knowledge following general deductions :of the heat energy given to the meteorite might be taken (a) That the velocities of meteorites are materially changed to be known. To find the temperature distribution in the by the resistance of the atmosphere, and, in general, by a interior of the iron or stone I have adopted the approxi- fractional part of the velocity which is independent of the mation of considering the meteorite to be cylindrical, and velocity of approach. then utilising ordinary cylindrical coordinates. During the (b) Íhat the superior limit for incandescence is probably investigation a good many results were obtained which in

about 150 miles above the earth's surface. dicated methods by which the simple labour of the work (c) That no iron meteor the original weight of which was could be lightened. Some of the more cumbersome ex- less than 10 to 20 lb. reaches the earth's surface, and that pressions could be simplified by dividing the distance between when a meteor does do so the temperature of its centre is the earth's surface and infinity into two regions, that within not in general above that of liquid air (assuming the the sensible effect of the atmosphere and that without.

temperature of space to be zero). Many results obtained during the investi

I am aware that the whole structure of the investigation gation. In the large meteorite it was found that for

rests on the evil principle of extrapolation, but until man all velocities of approach the temperature at the centre is capable of experimenting with velocities of 10 or 20 miles was a most minute fraction of that at the surface. For a second, and surviving thereafter to record his results, no the small meteorite it was found that the final velocity was other manner of investigation seems possible. always very small and the time of flight correspondingly London, November 13.

H. E. WIMPERIS. great, with the result that the whole of the material would be consumed before reaching the earth's surface—this would

Mount Everest : the Story of a Controversy. then properly be termed a meteor, not a meteorite. In its turn this consideration gives the altitude at which incan- I have read with interest in your columns under this descence would occur. The small iron meteor would burst title a carefully compiled and instructive account of the into brilliance at 45 miles up, and the stone one at 68 miles. discussions that have from time to time during the past To obtain a superior limit to the point of incandescence I fifty years broken out with regard to the naming of the assumed a meteor the diameter of which was only a highest measured point on the earth's surface, Peak XV of millionth of an inch. For iron, brilliancy obtained at the Indian Survey. 106 miles, and for stone at 129 miles. These figures are I have long maintained it to be a matter for regret that the obtained by assuming the meteors to have the maximum monarch of mountains should be called after any individual, velocity which the earth could impose. If, however, an however eminent, and I am still of this opinion, which initial velocity of 250 miles per second be assumed, surely is shared by most mountaineers and mountain lovers. We a superior limit, incandescence would occur some 35 or 40 should prefer that Peak XV should bear a Nepalese or a miles further off, so that the greatest height for visibility Tibetan name, even had one to be invented for it, as twenty would lie well within some 170 miles.

years ago Alpine Clubmen, in accord with Russian surveyors, An iron meteorite 3 inches in diameter falling to the found or invented native names for many of the great peaks earth from an infinite distance would begin to get warm of the Caucasus. about nine seconds before reaching the earth, and continue But, since your correspondent appeals to me not to prolong to increase in temperature for about seven seconds, after the controversy further, I must remind him that the opinion which its velocity would be practically “killed," and two I have expressed is an individual and not an official opinion. seconds later it would reach the earth at about two-thirds For ten years I have had no official connection with the of a mile per second. This represents a typical case for Royal Geographical Society. what might be termed the “ twelve pound shell size.

Should the council of that body resolve that, considering In the twelve pound shell ” size the internal temperature the length of time the title “ Mount Everest " has been more falls off very rapidly towards the interior. Thus, taking or less in use in this country for Peak XV, the absence of the mean temperature in the severest case as 1.00, the any evidence that that individual peak is designated as, or surface temperature was 2.2, and at a depth equal to a included in the designation of, Gaurisankar by the Nepalese, fifth of the radius (0.30 inch) the temperature was about and the practical inconvenience (whether the name be 03 only, whilst at the centre it was 0.0016. So that for authentic or not) of introducing a new Tibetan name such the most excessive surface temperatures the central tempera- as Chomo- or Jamokangkar, it is expedient that the title ture would be well below the temperature of liquid air, Mount Everest should be generally accepted, I shall assuming, of course, that the initial temperature of the acquiesce. For I attach greater importance to the general meteorite is at the absolute zero.

principle than to the particular case, and I believe the proThe steepness of the heat gradient at or near the surface tracted discussion and many protests summarised in your is the probable cause of the nodular appearance of columns have served their purpose in helping to discourage meteorites. Great resistance to the inward flow of heat the practice of giving personal names to mountains. would be offered by any internal veining, and as a result I should add that foreign geographers are not, as your such surfaces of separation would tend to become the limit-correspondent suggests, mainly dependent on the Geoing surfaces for any burning which might occur.

graphical Journal for information in this matter. Captain The various formulæ used to obtain the above results Wood's report has been noticed in that well known periodical were suited to a subsidiary investigation, viz. that of the Petermann's Mitteilungen. problems connected with the ejection of rock from terrestrial

DOUGLAS W. FRESHFIELD.

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