142 



KNOWLEDGE. 



[JUNB, 1902. 



hardening in si)irit8 of wino, nnd clearing in clove oil, they 

 should be placed in turpentine and mounted in Canada balsam. 



Full particulars of the above processes will bo found in the 

 many works that give instructions in mounting. 



Advici; in rui;i'AUiNi; Si>F.riMi-.NS. -At this time of year 

 many microscopists will be collecting specimens which will 

 prove interesting under the microscope, and would, no doubt, 

 in many cases, wish to permanently iireserve them. I shall be 

 pleased at all times to give any advice or assistiince I can to aid 

 in such work. 



NOTES AND QUERIES. 



I{. W. .S. — Dcsmids should grow well in a shallow cell in 

 some of the water in which they were found ; taj) water will 

 not do. I am unaware of the existence of the article in the 

 journal you mention. 



T. II. ^4.— The specimen you send is not sufficiently perfectly 

 mounted for identification, but it looks uncommonly like the 

 Spinning Mite of the lime tree, Tdruuychus telarius. 



hinoramus. — Good portable microscopes, as well as instruments 

 suitable for the purpose of an amateur, are supplied by all the 

 makers whose advertisements appear in these columns. For 

 examining flowers, etc., Mr. C. Baker, of 244, High Holborn, 

 makes an especially convenient little instrument called the 

 " Plantation " microscope, which would probably do all you 

 require. Good second-hand microscopes can be obtained from 

 several houses, and particularly Messrs. Clarkson & Co., of 

 Bartlett's Buildings, E.C. The book that you would probably 

 find most serviceable is " A Popular Handbook to the Micro- 

 scope," by Lewis Wright, price 2s. 6d. 



C. M. — I have referred your letter to the gentleman who has 

 kindly consented to act as consultant with regard to Rotifera, 

 and he replies as follows : — " I am afraid that the smaller 

 Entomostraca are, like the poor, always with us. When 

 collecting myself, I pass all the water through a small strainer 

 (sold in the streets for a penny), and I find that this keeps out 

 all the larger forms such as Daphnia, etc. I must admit I do 

 not find many free-swimming Rotifers as large as Daphnia or 

 Cyclops, unless the latter are very small, but I think your 

 correspondent would find it jiossible to make a muslin strainer 

 coarse enough to let through most of the Rotifers, and at the 

 same time keep out all the large Entomostraca. But to get rid 

 of Cypris and Chedorus I am afraid will require a pipette and 

 infinite patience." 



Correspondence is invited on the subject matters dealt with 

 in these columns. Readers may see subjects from different 

 points of view and their criticism will be welcomed. 



Communications and enquiries on Microscopical matters are 

 cordially invited, and should he addressed to M. I. Ckoss, 

 Knowledge Office, 326, High Holborn, W.C. 



NOTES ON COMETS AND METEORS. 



By W. P. Denning, f.r.a.s. 



New Comet (1902 A).— A new comet was discovered by Mr. W. R. 

 Brooks, of Geneva, U.S.A., on the morning of April 15th, when it 

 was in about 344' + 29°, and two degrees north of |S Pegasi. The 

 comet was travelling rather quickly to the south-east, and it was 

 observed on April 17th by Prof. E. Hartwig, at Bamberg, who 

 described it as of 8.V magnitude, about three minutes of arc in diameter, 

 and with a tail nearv half a degree long. The object approached the 

 8im so rapidly that it was only observed for a short period, and it 

 arrived at perihelion on May 7th, when in a position about 25 degrees 

 south of that luminary. Thereafter the motion was directed towards 

 north-east, but it soon slackened and prevented the eomct from 

 emerging from the sun's rays to become visible in the evening sky. 

 The object receded rapidly from the earth, and its apparent brightness 

 declined to such a degree that it is questionable whether it was seen 

 at all after its perihelion passage, except from stations in considerable 

 south latitude. The comet's apparition may be regarded as a very 

 fugitive one, and the conditions appear soinev\hat similar to those 

 which affected the great southern comet of last spring, and confined 

 its visibility to narrow limits 



Gheai Detonating Fikeball seen in Sunshine.— On the 

 morning of April lUth, at about lOh. 55m. G.M.T., when the sun was 

 shining brightly, a large fireball was seen in the northern sky from 

 Dunsink, Co. Dublin, and Carlow, and at about the same time a strange 

 i^ound was heai'd over East Tyrone by many people, who were startled 



at its unusual character, and considered it either the presage or 

 u('<^oinpaniment of an earthquake. .\ large number of 'descriptions of 

 the i)henomenon have been published in the Iruh Timet, and a few 

 ac<'uunts have been privately communicated. From these the 



following are selected ;-- 



Mrs. Martin, of Dunsink, says:-" While walking down the fields 

 iTiy atenttion was attracted by a rushing noise above my head, and 

 glancing up I saw a beautiful pear-shaped object, with a tail about 

 six times as long as the head, going in a northerly direction. The 

 head was of dazzling brightness, liaving the appearance of the electric 

 light, and changing to a golden shade before it vanished. Ar I 

 wat<!hed the object the tail suddenly broke in two, leaving the pear- 

 shaped head and part of the tail separate ; then the broken tuil seemed 

 to rush into the head, and drop out of sight. Before T saw the 

 object, and all the time I was watching it, which could only liave been 

 for tlirce or four seconds, I distinctly heard a rushing soimd T first 

 saw the meteor when directly over my head, and it disappeared at an 

 angle of 10" from the N. horizon." 



Herr Boeddicker, of Lord Rosse's observatory, Birr, writes to Iho 

 Irish Times of April 27tli as follows:— "My attention has been 

 drawn to numerous letters concerning a rumbling sound heard over 

 East Tyrone, and ascribed by various writers either to a meteor or an 

 earthquake. That the former explanation is the true one is established 

 beyond a doubt by the fact that Master R. FitzMaurice, of Carlow, 

 saw the meteor at the same time, viz., lOh. .30m. (Dublin time). It 

 flashed into sight in the N.E. in full sunlight, and left a long train 

 behind." 



Willi regard to the strange sound, the Rev. E. F. Campbell, of 

 Moy, says it occurred at lOh. 30m. (Dublin timet, and that he was 

 standing talking to his gardener at the time. The morning was 

 perfectly still, the sun shining, and mist rising. "The sound seemed 

 to be very deep in the heavens ; to the east it appeared to be far above 

 thunder distance, and about half as loud. It lasted from 30 to 60 

 seconds, and I can only describe it as being like the whirringof a very 

 large motor with a deep tone. I looked steadily at the point it seemed 

 to come from, but could see nothing, possibly, or probably, owing to 

 the thin rising mist " The Rev. E. F. Hutching^ of Market Hill, 

 Co. Armagh, says '' that a great rumbling sound was heard there on 

 Thursday, April 10th, at about 11 o'clock a m. (Dublin time), and 

 lasted about eight seconds. I have no, doubt whatever but that it 

 was of seismal origin, it being a full round booming sound, pervaded 

 by a regular wavy rumbling There was an absence of any crashing, 

 detonating, or rippling sound, such as more or less distinguishes the 

 explosion of meteorolites. There was no tremor in the ground or air 

 that I could perceive, but a boy of eleven years, working in a garden 

 when be heard the sound, ran and said the garden was shaking." 



There appears to be no doubt, however, that from the near corre- 

 spondence in time between the rumbling sound and the visible 

 disruption of the fireball, that the whole phenomenon was meteoric. 

 It will be interesting to hear of further observations of the fireball, 

 which seems to have been a particularly brilliant object, even in the 

 presence of the sun, over the north-east region of Ireland. As seen 

 from Duosink, the meteor disappeared at an estimated altitude of 10°, 

 and if its position was then over Tyrone, in the neighbourhood of 

 Dungannon, its height must have been 15 mUes. The probable 

 radiant point would be in Pegasus, near /? Piscium, or in the eastern 

 region of Aquarius if the direction of the fireball's flight was from the 

 zenith to near the northern horizon, as observed at Dunsink. 



Lak&e Meteoe. — Mr, G. Fisk, of Eccleshill, Bradford, wTites 

 that he observed a meteor brighter than Venus on April 20th, 

 lOli. 42m. It appeared to shoot from near a Draconis, and disappeared 

 near y Ursae Mmoris. It was intensely blue in colour, and cast a 

 distinct shadow, though the moon was almost at full. Duration of 

 flight, about 1^ seconds. It left very- little trail. This meteor, though 

 it appeared on the date when Lyrids are unusually numerous, was 

 directed from the region of !; Ursae Majoris and a Canum Venaticorum, 

 so that it could not have belonged to the periodical shower of April. 



THE FACE OF THE SKY FOR JUNE. 



By W. Shackleton, f.r.a.s. 



The Sun. — On the 1st the sun rises at 3.51 a.m., and 

 sots at 8.4 P.M. Ou the 30th he rises at 3.48 a.m , ami 

 sets at 8.19 p.m. 



Summer commences on the 22nd, when the sun is at the 

 solstice, on which date he remains above the horizon fur 

 16h. 35m. 



Sunspots are infrequent; at the time of wriliuL,' the 

 sun's disc is devoid of spots. 



