258 PROCBEDINdS AT m E T I N G d .

!Che following Papers were read :-

‘ ,A CURIOUS CASE OF DAMAGE BY LIGHTNING.” By ALFRED HANDS, F.R.Met.Soc. (p. 226.)

ON THE MEAN TEMPERATURE OF THE AIR AT THE ROYAL OBSERVATORY, GREEN- WICH, AS DEDUCED FROM THE PEOTOGRAPHIC RECORDS FOR THE FORTY YEARS FROM 1649 TO 1886.” By WILLIAM ELLIS, F.R.A.S., F.R.Met.Soc. @. 233.)

ON TEE COMPARISON OF THERYOXBTRICAL OBSERVATIONS MADE IN A STEVENSON SCREEN WITH CORRESPONDIXG OBSERVATIONS MADE ON THE REVOLVING STAND AT THE ROYAL OBSERVATORY, GREENWICH.“ By WILLIAM ELLIS, F.R.A.S., F.R.Met.Soc. @. 240.) .

Ii PIIONOMETER.” By W. F. STANLEY, F.G.S., F.R.Met.Soc. (p. 250.)

SOME SUGGESTIONS BEARING ON WEATHER PREDICTIONS.” By ALEX. H. MACDOWALL, M.A. (p. 252.)

CORRESPONDENCE AND NOTES. h EXPERIMENT SHOWING THE EFFECT OF ELECTRIFICATION UPON THE CON-

WATER is boiled in a small tin bottle, furnished with a cork through which passes a glass tube terminating in a nozzle of about 1-16th inch aperture. The shadow of the steam as it issues from the nozzle, .when cast upon a white screen by a powerfnl light, appears under ordinary conditions to be of feeble intensity and of a neutral grey tint, showing that the steam is nearly transparent. But if a discharge of electricity is directed npon the base of the jet of s t e m by means of a bundle of needle points in connection with an influence machine, the shadow at once becomes dark and dense, at the same time assuming, especially near its edges, a peculiar orange-brown hue. The electrical discharge appears to act by promoting coalescence of the exceedingly minute particles of water contained in the jet, thus forming drops large enough to obstruct the more refrmgible rays of light.

The experiment suggests 8 possible explwmtion of the intense darkness of thunder clouds, as well as of the lurid yellow glow by which such clouds are often distin,~shed.

DENSATION OF STEAM. By SHELFORD BIDWELL, M.A., F.R.S.

FURTHER NOTE ON THE RELATIVE PREVALENCE OF DIFFERENT WINDS AT THE By ~VILLIAM ELLIS, F.R.A.S., of the

T ~ ~ p a p e r which I communicated last year to the Royal Meteorological Society 011 the above question’ was prepared with the object of showing whether the increased prevalence of North-east winds which Mr. Prince had found in recent years to exist at Crowborough was indicated ah0 by the Greenwich records. In that paper I compared together the results obtained by Ivir. Prince from one observation daily at 9 a.m., with results for Greenwich tak‘ 0‘ into account the whole twenty-four horns. This was done simply because the%reenwich results esisted in such shape avJlable for immediate use. Eir. Prince took exception at the time to the comparison made in this way, and indicated his belief, as I under- stpod, that ifthe comparison of his results had been made with correspondin, -Green- wlch results, that is with such as would have been obtained by discussion of the observed indication of the wind at 9 a.m. only, much of the discordance wodd

ROYAL OBSERVATORY, GREENWICH. Royal Observatory.

1 Quarterly JOW, Yol. XVI, page ‘221.

CORRESPONDENCE AND NOTES. 259

have disappeared. I am afraid that I may not have appeared to give due atten- tion to his remarks on this point, one reason that weighed with me perhaps being that my examination of the Osler anemometer record, day by day, through a long series of years, had certainly not impressed me with any idea that the difference in the results found for the two places could be due to the circumstance that, in the discussion of the Greenwich winds, the whole day was considered, instead of 9 a.m. only.

In Mr. Prince's Report for the year 1890, of which he has kindly favoured me with a copy, I observe that he reiterates his objection to the method of comparison adopted. I t seems, therefore, desirable to make the comparison in the way sng- gested by him. I t happens that the Meteorological Beport that we send daily to the Meteorological Office, and in other directions, includes the direction of the wind at 9 a.m. as taken from the anemometer record. These directions I have now discussed for the years 1885 to 1889 to which Mr. Prince again refers. Unlike the resillts before given, these have been tabulated as referred to sixteen points of the compass, instead of eight. And since it is not a new extraction from the Osler record that is now made, but simply the employment of the daily directions of wind as given in reports all prepared before the discordance mentioned by Mr. Prince was (in the year 1890) pointed out, any possibility of individual bias in the preparation of the results becomes removed. In saying this I cast no reflection, wishing simply to make clear the thorough independence of the Greenwich result.

TABLE I.-NUJIBER OF DAYS OF PREVALENCE OF DIFFERENT WINDS IN EACH YEAR, I88j TO 1889, AS DERIVED, AT 9 A.M. ON EACH DAY, FROX THE RECORDS OF TEE SELF- REGISTERING OSLER ANEYOYETER OF THE ROYAL OBSERVATORY, GREENWICH.

Year. ' I

To reawe the numbers of Table I. to eight points of the compass, half the nimber of days of North-north-west wind, and half the number of daysof North- north-east wind were in each year added to the number for the North wind, and SO on. The results as referred to eight points are contained in Table II., adding thereto the previous Greenwich means, and also the Crowborough means.

TABLE I I . - N U M B E n OF DAYS OF PREVALENCE OF DIFFERENT WINDS AS GIVEN I N TABLE I. REFERRED TO EIQHT POINTS OF THE COXPASS.

Year.

-_---. ISSj 1886 1S87 1sss 1889 -_--------_I__

-___---__---I-- Mean, Greenwich 9 a.m. direction .... Mean from previous paper, Green-

-

m

48 55 34 20 4" 3s 54 32 18 42

46 53 25 18 45

------

61 60 zz g zE

5 0 48 22 I S 37

48 5 1 27 17 39

} 149 wich whole day direction.. .. ... ... 5 2 35 23 37 ______-----I

Mean, Crowborough 9 am. direction . . I +I 1102 ____-. ___ -- ----

ZI I zz 38

260 CORRESPONDENCE AND NOTES.

By the substitution of the 9 a.m. direction for that for the whole day st Green- wich, the mem niimber of days of North-east wind becomes increased from 52 to 54, and the number of slays of South-west wind decreased fkom 100 to 92, both changes, though small, being in the direction of bringing the numbers more into harmonywith those of Mr. Prince. But thenew Greenwichnumbersfor North-east and South-west winds are still widely different from those of Mr. Prince. The difference is, therefore, not t o be explained in the way supposed. One curious point is that the numbers for other winds are in general in good agreement.

THE L L 11331s FATUUS,” OR, WILL 0’ THE WISP. By F. RAMSBOTHAM, F.R.Met.Soc. FOR some years now, since’ I have been living at the Warren, Crowborough, in Susses, I have, in common with many others, been struck by seeing Will 0’ the Wisp, or X p i s Fatuus, playing about in the evening at various times, sometimes in one place, sometimes m another, and sometimes two at once, but not in the same place. Now I have observed that these appearances always coincide with unsettled weather, that is, that bad weather has invariably followed their appear- ance-in fact, it is quite a storm warning to us, as bad weather is sure to follow sooner or later, generall sooner. On Saturday, Septemzer 26th, 1891, one of my brothers and myself watched

one for some time, md last night (October 1st) it appeared in the same place and was visible quite half-an-hour. I t does not dance about, but now and then takes a gracefid sweep, now to quite a height, and then makes a gentle curve down- wards, after sparkling and scintillating away for ten minntes or more.

In the winter there is generally a very remarkable one which appears to rise in Ashdown Forest beyond this estate, which I have known to keep steadily in the air for half an-hour, and then sail away a long space and stop again. oln keeper has seen it dozens of times, and in every case bad weather followed.

SOUTH AFRICAN WEATHER 1890-91. By C m s COWEN. &Ir. COWEN, in B letter from Johannesburg, dated April 1691, says :-I‘ Nem-ly every mail from beyond the Equator to South African ports, for months past, has brolight news of the phenomenal winter which has covered the Europerm belt of the northern hemisphere, increased mortality to an unusual degree, and clone vaet damage to property.

l L To readers on the northern side of the globe, it may be of interest to have attention drawn to what has been transpiring meteorologically on this side ; and for some to consider whether beneficial results of m y kind may be obtained by extending systematic observations to at least the principal parts of this Continent, now being widely embraced by the white race, in addition to what is done by the Meteorological Commission of the Cape of Good Hope, whose observers touch Bloemfontein in the Orwge Free State, and Johannesburg and Rushen- burg in the Transvaal.

“While the winter in Europe and North America has been one of greater hwdness, and its range wider than has been known for man years, the corre- spondmg period (our munmer), in portions extending from gmbezia towards the Cape, has been remarkable for the rains and stoims that have prevailed. They began in the Trmsvaal at an unusually early date ; and I find that the Free State, Natal, the Transkeian Territory, and sections of the Colony had these early downpours as we have had them-often accompanied by high winds asd heavy electric storms, with brief intervals to the present time. Mniiy of these fierce storms synchronised with distressing snowfalls and extreme frost on the northern half of the globe (reported to us by cablegram).

4 ‘ I do not give details here, because too many of them would be required to be of practical use to the readers of SO brief a paper as this must be. Those who care to follow up the subject will find all the information at present recorded in the files of Sonth African newspapers et the Royal Colonial Institute, the offices of the Agent-Geueral For the C:\pe of Good Hope, Sir Charles Mills, K.C.M.G., the CrownAgents for Natal, and the Consuls-General iu London for the South