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I understand, Dr. Chree's basis for his most anxious them, despite the protests of such men as Davy. Wclasica doubts ; and the object of my letter was to try to remove and Berzelius, cannot be decomposed or disintegrated, tiat least this form of doubt from the minds of astronomers an hypothesis to the contrary must be rejected. and responsible magneticians.

(6) But the recent discoveries in radio-activity are oppsd One more quite minor point I may take the opportunity to this. It has been shown that the radio-actise elemis of mentioning, though it is connected rather with a letter are disintegrating slowly and gradually from their own of Dr. Chree's in the Times than with his letter in internal energy. The process has been going on for inNATURE.

definite time, although only lately discovered accidental, (7) Disturbance of terrestrial rainfall-say an increase because of certain radiations. Have we reason to beliete for a short period due to influx of cosmic nuclei-need not that it is limited to these elements? Prof. Rutherford be supposed to modify the usual local distribution of rain, has pointed out that the existence of rayless changes in but only to increase its amount in the customary localities. these elements “indicates the possibility that undetected

This I only vrnture to say very tentatively, and with changes of a similar character may be taking place in the no dogmatism at all. It is clear that the total rainfall non-radio-active elements” (“* Radio-activity," P: all over the earth during a long period cannot exceed what 2nd edition). If we suppose that such changes took piare the sun can rvaporate in approximately the same period, at the outer surface of the moon's atmosphere, resulting and therefore depends more on the sun's total activity than in particles sufficiently small, then part after part of the on anything else. It is also clear that rain is a local atmosphere may have been stripped away until the present circumstance, and that the conditions which determine condition has been reached. whereabouts rain shall fall are mainly local. But I ques. (7) The same process may be going on now with the tion whether either of these propositions really negatives earth's atmosphere, notwithstanding the greater force of the idea that cosmic causes may occasionally affect the gravity: rainfall during any given month, even in a specified Briefly, if the atmosphere of the moon was erer driven lo ality.

OLIVER LODGE. away-the repulsive force of the sun (pressure of lign:) is

the only driving force we know of-the component particles

must have been originally too heavy to be driven off, and Why has the Moon no Atmosphere?

were therefore in some way reducible; the transformations

in the radio-active elements suggest possible process. L'ROCTOR (" The Moon,"p. 334) says :-—“ It has been held, Thus the present condition of the moon is an argu. and not without some degree of evidence in favour of the ment for the disintegration of some of the non-radio-active theory; that in our Moon we have a picture of our Earth, elements, and the argument is the stronger in proportion 10 as she will be at some far distant date ... when her the difficulty of finding a solution otherwise to this old and atmosphere have disappeared through the

astronomical problem.

ALEXANDER JOHNSON, action of the same circumstances (whatever they may be)

Montreal, Canada, September 30. which have caused the Moon to be airless and oceanless."

The following considerations suggest what the circumstances referred to may have been, and present what seems

A “Canaan Stone." a possible cause for the absence of an atınosphere. (1) Apart from all theory, we know that the sun exerts

Captain B, of the Brixham (Devon) trawler fleet, a repulsive force on matter around him. The phenomena recently showed me what he termed a “Canaan stone, of comets' tails show this as clearly as the streamers from

He told me that in the hands of his wife's mother it had a flagstaff show that a wind is blowing. Kepler first effected many miraculous cures of diseases of the eye, and suggested the existence of this force. Sir John Herchel, that by its use she had been especially successful in curing in his essay on comets, said, more than forty years ago,

cataract. The stone

a polished sphere of agate, that they have furnished us with a proof, amounting to

translucent, and of a faintly greenish-yellow tint, containdemonstration, of the existence of a repulsive force directed

ing several red-brown patches due to the presence of iron. from the Sun."

It was about l-inch in diameter, and had been drilled (2) Maxwell in 1873, deduced from his electromagnetic through the centre, as though it had at one time formed theory the pressure of light, which Arrhenius in part of a necklace. The treatment simply consisted in ajiplied to explain the formation of comets' tails. Each striking (i.e. gently rubbing) the eye with the stone. particle projected from the comet, under the influence of No prayers or incantations were used, but it was essential the sun's heat when nearing the sun, being submitted to that different parts of the stone should be used in different two opposing forces, viz. gravitation and the pressure of diseases, and the part used also varied with the colour of light, he pointed out that since the pressure varied as the patient's eyes. The stone was rubbed actually on the the surface, while the weight varied as the volume, i.e. conjunctiva, not on the lids. The secret of the exact one compared with the other, varied as the square of a

method of treatment died with the old lady, who is renumber compared with its cube, then, when the particles ported to have had quite an extensive ophthalmic practice, were small enough, the repulsive force of the pressure

and I was appealed to in order that I might explain the might be many times as great as the force of attraction, secret to the present owners of the stone. Beyond the fact and drive away the particles with great velocity.

that the stone had been bought by its late owner from As a common example of such action, I may remark a man in Cornwall for 401., no history was available. that we have the case of a wind blowing on a newly The following extract from the Book of Tobit sudmacadamised road or a single stone on the road. gested itself to me as a possible explanation of the origin Ilhile the stones are unbroken the wind cannot

of the belief in the curative value of the stone :them, but when they are crumbled to powder it sweeps

" When Tobias and Raphael came to the river Tigris, 2 them away in clouds.

fish leaped out of the water and would have devouri-d him, (3) In this way the sun exercises a sort of sifting process but the young man laid hold of it and drew it to land. in space, sweeping away very small particles and drawing The Angel bade Tobias open the fish, and take the heari. the larger ones towards him.

and the liver, and the gall, and put them up safely. (4) Assuming that the moon had an atmosphere for And the Angel said . . . As for the gall : it is good to many ages, the particles would be acted on by the repulsive anoint a man that a whiteness in his eyes shall be healz. force of the sun radiating from its centre, and by gravity

Tobias met his father at the door, and strake of the directed to the centre of gravity of the moon. During the gall on his father's eyes . . . and Tobit recovered to time that the moon retained its atmosphere it is evident sight. that gravity must have been the preponderating force. It does not require a great stretch of the imaginatin The atoms, as Dalton called them, were not small enough see a resemblance between this translucent, greenisha to allow the pressure of light to prevail over the weight. vellow stone, with its red-brown patches, and the distert!

(5) But the atmosphere has disappeared, and we have to gall-bladder of a fish, excised with small portions of account for this fact. Can the particles have been in any adherent to its surface. The expression " to strika," : WAV reduced in size?

to anoint or rub, is still quite common in Devon. In the If we are sure that the chemical atoms, as Dalton called country districts a usual treatment for sprains or abras

was

1900

on

move

to

is to "strike them with fasting spittle,” i.e. to apply sky was clear over a large extent of England, and hundreds saliva when rising in the morning, before any food has of persons saw the meteor, though only a small proportion been taken.

G. HAROLD DREW. of that number have reported their observations. Marine Biological Laboratory, Plymouth.

The great daylight meteor of 1900 January 9 was

directed from Aquila, that of 1894 February 8 emanated Ortbite in North Wales.

from Hercules. It is seldom that meteors appearing at

such times can be suitably observed, as the sky does not Is March, 1908, an unfamiliar mineral was discovered

afford any reference objects such as is furnished by the by Mr. W. G. Fearnsides in a narrow vein which traverses

stars at night.

W. F. DENNING. the intrusive granophyric mass of Tan-y-grisiau, near Ffestiniog, and was submitted to me for identification. It has proved to be the somewhat rare silicate orthite,

An Aurora Display on October 18. and its occurrence will be of considerable interest to I WITNESSED last night one of the finest displays of the mineralogists both on account of the amount of material aurora borealis which it has been my good fortune to see available and for the large size of the crystals, which range in this country. It happened at about 9 p.m., and I up to 1 inches in greatest dimension.

was at the time upon one of the highest summits of the Hitherto orthite, which contains a number of the rarer Cotteswold Hills, close upon 1000 feet above the sea-level, cleinents, such as cerium, lanthanum, didymium, yttrium, so that I had an uninterrupted view of the magnificent dc., has not been found in any quantity in Britain, and spectacle. The first I saw of it was several streamers then only as microscopic crystals and grains. The crystals and an indistinct band low down on the northern horizon, from Tan-y-grisiau are well-forined, black to dark grey, with a detached red, cloud-like portion almost due west. submetallic tables with bright faces; they are conspicuously These resolved themselves eventually into two bands, the tabular, parallel to the form T{100, and are modified by uppermost stretching right across the sky from north-west narrow prisin and dome faces.

to north-east, and during the maximum phase of the It is the “unknown and very interesting mineral ” to phenomenon was a truly grand spectacle, with numerous which the attention of those members of the Geologists' streamers connecting the two bands. The uppermost band Issociation who took part in the long excursion to Northfinally faded away, leaving the lowermost one still visible Wales this year was directed.

but very indistinct, with two or three faint streamers The exact locality is the north-west face of a quarry at shooting upwards. Cein-hvchan, south of Tan-y-grisiau, Blaenau-Ffestiniog, I take this opportunity of inquiring what is the most belonging to the Ffestiniog Granite Quarries Co., Ltd. austral or equatorial limit from whence the aurora borealis

The physical properties of the orthite are undergoing is visible, or rather has ever been observed? This subject investigation, the results of which will be published at a is of particular interest to me from the circumstance that later date.

HERBERT H. THOMAS. when I was at Darjeeling some years ago I was informed Geological Survey and Museum, Jermyn Street, S.W. that the phenomenon had been seen from thence, although

this well-known hill station is so far south as 27° north

latitude. Although it is not impossible for it to be seen Drought in South-west Ireland.

from the altitude of Darjeeling (which is 7500 feet above WHILST all round us have been reports of wintry the sea-level), for far away are seen the tops of the Himaweather and unceasing rain during the summer months, we layas, I feel convinced that what has been seen from thence, in this small south-westerly area of Ireland have been and mistaken for the aurora, is nothing more than the afterpassing through a period of abnormal drought, in fact a glow or reflection from the snow-fields and glaciers upon record season, accompanied by high temperature through-exceedingly thin masses of aqueous vapour, or rather

spicules of snow, floating upwards to 1000 feet or more I have recorded the annual rainfall here (Bandon) for above the summits of the highest Himalayan peaks. This some years, but I have never had anything approaching a latter phenomenon I frequently witnessed after sunset, and, similar experience, and the oldest inhabitant here cannot it certainly possessed the appearance, upon many occasions, recall so continued an absence of rain as we have felt of the aurora, hence the mistake, possibly, of unscientific this season, that too in a country where the rainfall is observers.

W. HARCOURT-Bath. generally excessive. I am bound to say, however, that

October 19. the elements are now distinctly making up for lost time, as though in revenge for letting us off so easily before. I give you the rain-gauge readings for the months June,

Jupiter's South Tropical Dark Area. July, August, and September, which speak for themselves, All the transit estimates, numbering fifty-two, of the and may perhaps prove of some interest to your readers. south tropical dark area on Jupiter, obtained during the

The readings were taken with a 5-inch Negretti and apparition of 1908-9, have been reduced to longitude. The Zambra gauge, and registered daily :

area in 1908 December was found to be more than 50° June.—Total for month, 1.08 inches. Twenty-five days in length at the south equatorial belt. From this date to absolute drought. Highest reading =0.47 inch, on June 24. the close of the observations in 1909 June its dimensions

July.—Total for month, 1.02 inches. Twe -three days exhibited a gradual increase, and in the latter month it absolute drought. Highest reading =0.34 inch, on July 10. covered considerably more than 90° of longitude. This

August.—Total for month, 0.54 inch. Twenty-five days longitudinal growth was due chiefly to a marked difference absolute drought. Highest reading=0.32 inch,

in the observed rate of velocity of the two ends of the August 1.

While the preceding end drifted at a pretty normal September.-Total for month, 0.41 inch. Eighteen days rate of 150 per month in excess of the adopted zero meridian absolute drought. Highest reading=0.08

= inch, of System II., the following end exhibited a monthly drift September 28.

GEO. A. ARMSTRONG. of only go. The following part of the area, therefore, was Ardnacarrig, Bandon, Co. Cork, October 13.

not keeping pace with the preceding portion, and accordingly the object itself became distended in longitude.

The mean rotation period of each end, as well as the The Meteor in Sunshine, October 6.

middle, of the area would seem to have been as under :The great daylight meteor of October 6 was observed

Number of
Mean daily

Mean rotation by many persons in various parts of the country. The observations rotations

period particulars to hand are not, however, very definite, and

h. it is scarcely possible to compute the real path of the

430
- 0:4823

9 55 20 8

16 object. From a comparison of about fifteen descriptions,

295
- 037 54

9 55 253 there seems little doubt that the meteor moved in a direc

16
379
-0.2989

9 55 28-3 tion from south to north over Reading, Thame, and on to The above period for the following end is the longest that a termination near Market Harborough.

has been recorded, either for this or any other part of the The radiant point was in Leo, and it is hoped that more area, the existence of which became known in 1901 February. observations of an exact character will be supplied. The Leeds, October 15.

SCRIVEN BOLTox.

out.

on

area.

on

:

Number of

drift

m.

S.

20

FURTHER EXPERIMENTS WITH THE

physiologists; but, taking a hint from the use of GRAMOPHONE.

elasticity in the construction of the reproducer of the

gramophone and iinproved phonograph. I arranged IN N NATURE of April 15 I described a number of thin india-rubber bands so as to hold the keeper of the

experiments with the gramophone. Since then 1 tiny electromagnet about one or two millimetres from have continued to work on this interesting subject, the small soft iron cores, and so placed that the keeper and have at last succeeded in transcribing the vibra- was kept in equilibrium between two forces, at the tions of tones or chords as these are produced by the distance I have mentioned. I found that with this gramophone; that is to say, during the time that the arrangement, when the gramophone was played, the sounds are given forth. The method is illustrated in electromagnetic recorder gave forth the tune with the figure accompanying this paper (Fig. 1), and I also perfect accuracy, and when one touched the keeper it give several illustrations of the tracing so obtained. could be felt thrilling on the finger. The sounds of the gramophone are carried by a tin The electromagnetic recorder acted like a little tele. tube from the end of the arm of the instrument to phone. After many contrivances, I found the best which the horn or trumpet-resonator is attached, to a method was to place the recorder on the well-knowr

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Fig. 1.- Arrangement of apparatus. "Grainophone to the left. Observe the tin tube carrying the sound waves to the microphone. The operator is on

the right controlling the movable stage. The upper electromagnetic marker adjusted to the cylinder (revolving drum) registers the vibrations of the 1/1ooth per second tuning fork seen in the middle of the table. The lower electromagnetic marker writes the vibrations of the sound waves as these act on the microphone. While it is registering the lower marker gives forth the sounds played by the gramophone,

a

sensitive microphone. The microphone used was made Cambridge platform-stand, which can be moved up or by Herr Müller-Uri, of Brunswick, and was intended down by a finely cut strong screw (see Fig. 1). On to be used in the experiment of the singing-arc flame the platform I placed a device of my own, by which and also for a loud-speaking telephone. In the circuit I could adjust the marker on the smoked paper with of the microphone I have five or six dry cells giving a great nicety. On the same platform, as shown in the current of about five volts. In the same circuit is the illustration, I placed an electromagnetic recorder conrecorder, which is a very small electromagnet having a ' trolled by a 100 vib. tuning fork, so as to register on marker attached to the keeper.

the tracing 1/100ths of a second. The drum used In early experiments I used a large electromagnet was an old-fashioned Hawksley drum, well known to acting on a spring that carried a marker, but such physiologists, and it rotated at a speed that gave an arrangement only recorded notes or chords, as 12 inches per second. The paper was smoked in the regards intensity, but without showing the usual way over a camphor flame, and, after the stituent vibrations. It was not quick enough. tracing was taken, it was fixed by clear shellac Accordingly I adopted a small electromagnetic ar- varnish. The tracings shown are from slightly enrangement, like Deprez-signal,” known to larged photographs of a portion of each tracing, and

con

a

the length of each line, from side to side, represents made which was attached to the circular plate of in time oʻ3 second. Short descriptions of the tracings another gramophone, and having a circumference such are printed below the figures.

that the recorder traversed from 21 to 24 inches per The experiment was performed thus : After care- second. The two gramophones, one to play, the other fully adusting the markers on the smoked paper, the to carry the wooden drum, were driven at the same cylinder was allowed to rotate until it reached its speed. Tracings were thus obtained similar to the

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F«. 2.--Small portin of tracing of the Westminster chimes. The tracing begins at the left-hand corner at the bottom, runs along the line to the

right, then is cɔntinued in the next line above, again at the lower left-hand corner, and so on. The length of time represented by the length of one line from left to right is about one-third or a second. The tracings of the 1/1coth of a second are seen at the top. The tracing is from the portion of the record giving the strokes of i welve o'clock. Near the top little groups of waves indicate the beats, &c., alter the last stroke.

maximum uniform speed. By closing a key, a time indentations or waves on the gramophone record. record was taken. Then the gramophone was started; Trouble arose, however, from the oscillations of the the sound waves acted on the microphone, and the gramophone plate (one of the conditions of the success little electromagnetic marker began to sing or play; of the gramophone, in which all the arrangements are finally, by having my right hand at the top of the more or less mobile), but this difficulty was easily

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Fig. 3.-Small portion o tracing of a number of male voices s iging the "So.diers' Chorus" from Faust. Froin th: La Scala Theatre, Milan. The

uime relations, &c., are the same is in Fig. 2. Ubserve the complicated form of the curves.

screw, as shown in the figure, I was able slowly to surmounted. Finally, I found that with my arrangeraise the platform, carrying the recorder, so as to ment it was not necessary to use the gramophone, as describe a long spiral line, about 135 feet in length, it was easy to record the vibrations of a human voice from the bottom to the top of the cylinder. by causing the singer or speaker to sing or speak reaching the top, the experiment came to an end. To direct to the microphone. The arrangement is an

On

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FIG. 4.-Small portion of a tracing giving the vibrations of the voice of Signor Caruso in singing “Spirito Gentile." Time relations, &c., same as in

Fig. 2. Cbserve the crescendo and diminuendo of certain notes, the high pitch of others, and the regularity in form of the waves.

1

secure good results, great care had to be taken to excellent phonautograph. About five minutes are secure nicety of adjustment. It must be explained that occupied in taking a tracing, the average length of in the tracings so taken the recorder traverses which is 135 feet. 12 inches per second. The waves in my tracings are An inspection of these tracings shows the wonderful thus compressed laterally. To obtain waves at the variety of pressures pouring in upon the ear as we speed of the gramophone, I had a wooden cylinder i listen to music. Three or four or more notes differ. NATURE

[OCTOBER 21, 1909

ing in pitch may affect the ear in a second of time.
From ten to twenty vibrations, falling on the ear at

PEAT IN NORTH AMERICA.
a certain rate, are sufficient to arouse the sense of

FOR

OR many years peat was looked on as a source pitch of a tone of that frequency. It would seem that of fuel in poor countries only, where communi. with notes of low pitch, within limits, fewer vibrations cations were undeveloped, and where cottagers exare required to enable the ear to appreciate pitch, and tracted it by their personal labour for use in their own the opposite holds good with notes of high pitch. This household 'fires. To this day, the economist will corresponds with the fact that differences of pitch are probably find that this is the best and most practical difficult to detect both in the upper and the lower treatment of a peat-bog. It becomes idle in such limits of the scale of audibility, whereas a skilled ear cases to speak of relative calorific values, and to in the middle ranges of the scale can appreciate a point out that, even under present conditions of transdifference of one sixty-fourth of a semitone. The port, coal would form a more effective fuel. Where tracings also indicate approximately the pitch of any the right of digging peat over a certain

area is note registered. Suppose three small waves included in the rent of a small holding, this peat is spond to the wave of the one-hundredth of a second, dug at odd but suitable times, when the crofter or his then the pitch of the note will be about three hundred family might otherwise have remained idle. The cost per second, or (taking the middle c at 256) a little of labour thus becomes insignificant, especially where below f. The highest pitch I have mentioned is g", or creels are used for transport; and even the horse or more than 1500 vibs. per second, in the "Bell Song, ass must be fed, whether or no he is engaged in Lakmé (Delebes), by Madame Tetrazzini. I have drawing the red cart along the ridges between cutalso observed that the tracings show intervals in which away boglands, or down the grooved hillside from the there is a straight line, with no vibrations. If those i high-level deposit on the plateau. intervals are very short, then the interval may not be But from time to time capitalists have turned appreciated by the ear, even with the most careful longing eyes towards these stores of carbonaceous attention. In all the tracings the wave form is com- matter, and have sought to get rid of the 80 or 90 pound, not only owing to the existence of overtones, per cent. of water in the peat, and to produce a fuel but also because the voice is usually accompanied by economically capable of transport. Others have proan instrument, the piano, or an orchestra. I took one posed to produce gas at the bog itself; while others,

corre

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Fig. 5.-Small portion of a tracing from the record of the overture to Tannhäuser played by the band of the Coldstream Guards. Time relations, &c., as in Fig. 2. Observe the variations in pitch as indicated by the number of waves in a short period, and the irregularity in form of the waves.

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tracing of voice-tones (a bass voice) with no accom- / often with marked success, have manufactured mosspaniment.

litter for use as an absorbent bedding for city stables The most complex waves are those produced by the and dairy barns. blending of many voices or by an orchestra (see Figs. The various uses of peat have now attracted atten. 3 and 5). Here again there arises a curious considera- tion even on the North American continent. Messrs. tion. Suppose that in an orchestral piece all the E. S. Bastin and C. A. Davis have provided an introinstruments do not attack at the same instant, or if ductory manual on the subject in their description of one lingers after the rest the fraction of a second, The Peat Deposits of Maine" (Bulletin No. 376 of in both cases the wave form and the tracing picture

the United States Geological Survey, 1909, pp. 128). in general will be affected. If the want of coincidence They acknowledge that they have been preceded by passes beyond a limit, which it is difficult to define, Mr. Erik Nyström's treatise on “ Peat and Lignite : a musical ear finds the result defective, although one their Manufacture in Europe,” issued a year previously can scarcely tell why. Nothing has excited more in by the Canadian Department of Mines. Messrs. my mind a feeling of wonder at the powers of the Nyström and Anrep have now also published the ear than the inspection of these tracings. Is there a results of their “ Investigation of the Peat Bogs and damping mechanism, or is a damping mechanism Peat Industry of Canada, during the Season 1908-9 necessary? May it not be, after all, that our per- (Bulletin No. 1, Department of Mines, Canada, 1909, ceptions of musical tones, as in a musical composition, pp. 25). are the result of different modes of stimulating the The deposits in Maine are at present so little utilised ends of the cochlear nerves? May not innumerable that Messrs. Bastin and Davis direct attention to the varieties of pressures act on the nerve-endings, possibly various ways in which peat has become profitable as a whole, and send corresponding impulses to the elsewhere, and, we must admit, to the various ways brain? I confess that in the face of these tracings in which it has been worked without profit to anyone I find it more difficult to realise an analysis in the except the makers of machinery. The buildings and cochlea; but if not there, where does it take place ? heaps of scrap-iron lying derelict beside the bogs of That there is an analysis when we make an effort of Europe have not yet served to warn those who are attention there can be no doubt.

fascinated by some fancy process, put before them JOHN G. McKENDRICK. under seductive influences in the glamour of a weli-lit 1 I have to thank Prof. Noël Paton, of Glasgow, and Prof. MacWilliam,

exhibition. The authors of the United States bulletin of Aberdeen, for the loan of some portions of the apparatus.

have no false enthusiasms, and they lay proper stress No. 2036, vol. 81]

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