Februaky 1, 1898.] 



KNOWLEDGE 



35 



fine illustration of their theory ; but inasmuch as the flecks 

 and blotches are numerous on the pale egg, there must be 

 as much colouring matter on it aa on any of the others. 



The smaller end marking of eggs is a physiological 

 enigma well worthy of the attention of oologists. This 

 departure from the usual larger end marking is much 

 more frequent among the eggs of the I'alcuniihi- and the 

 Corviiiiv than among those of any other birds ; and in 

 looking through a series of twenty clutches of the sparrow- 

 hawk — now before me — I see thirty per cent, of the eggs 

 exhibit this peculiarity. Then, on the other hand, the sis 

 hundred clutches of the common house sparrow I have 

 in my cabinet, exhibit less than a dozen examples. 



Another question may be asked. Why do two birds of 

 the same genus, namely, the corn bunting and the 

 yellow bunting, oppose and support this style of colora- 

 tion ■' I have a very long series of the clutches of both 

 birds before me. In the former there are a very few 

 examples of smaller end marking, whilst in the latter there 

 is a large percentage ; and in some of the clutches all the 

 eggs have a circlet of fine lines around the smaller ends, 

 leaving the crown quite bald. 



I dare not trespass further upon your space beyond 

 expressing a hope that some of the scientific contributors 

 to your journal may write more fully upon this subject. 



Koyston, Herts. Joseph P. Nunn. 



A BRILLIANT METEOE. 

 To the Editors of Knowledge. 



Sirs, — It may interest you to know that an unusually 

 brilliant meteor was observed from here in dnyliijht at 

 5h. 7m. o'clock, Dublin time, this afternoon. It was seen 

 by several persons. My companion and I saw it first 

 about E.S.E., at a low altitude, perhaps twelve or thirteen 

 degrees above the horizon. It appeared to travel .slowly 

 across the sky in an almost horizontal line, slightly 

 inclining earthwards, and disappeared behind a cloud and 

 the hills to the S.E. 



The nucleus was very brilliant and large, and was 

 surrounded by a glowing greenish colour ; the tail tapered 

 to a point, and was pink along the margins and glowing 

 pale green on the central line. My companion describes 

 the colour as sparkling green. Another observer at a 

 distance from us (of five hundred yards or so) also observed 

 the green colour. Our point of observation was about 

 forty feet above mean sea-level ; our view eastwards down 

 the valley was unobstructed. Across the river to the S.E. 

 hills rise about five hundred feet high, and over these 

 some clouds rested ; otherwise the sky was clear, act! there 

 was ijiioil daylight. No noise was heard. The wind was 

 about S.W. and hght ; thermometer 52". 



Carrick-on-Suir, J. Ernest Grubb. 



Jan. 21, 1898. 



DISSOCIATION OF THE ELEMENTS. 

 To the Editors of Kxowledge. 



Sirs, — Dr. Emmens, of New York, has just published a 

 book in which he says that he has obtained a new 

 substance from iron and nickel, and the same substance 

 also from cobalt. He also says that he has converted 

 silver into a substance that cannot be distinguished from 

 gold and which appears to he gold. Is not this an 

 argument in favour of Sir Norman Lockyer's theory 

 with regard to the pre-nebular condition of matter ? He 

 describes it as being matter too tine to receive a chemical 

 name, which curdles and produces H. or something allied 

 to H. Further curdling goes on and the dust of Mg., 



C, O., Fe., Si., and S. is produced, etc., from which I 

 infer that he considers all the so-called elements to be 

 derived from one kind of matter. If the same substance 

 can be obtained from Fe. and Ni., and also Co., does it 

 not appear as if these so-called elements are derived from 

 one and the same kind of matter, or that they are 

 compounds "? — which latter is improbable. 



Again, if one element can be converted into another, 

 does it not seem probable that each so-called element had 

 one and the same origin ? Of course, we know that An. 

 and Ag. belong to the same group of elements, also Co., 

 F., and Xi. ; but might not this grouping of the so-called 

 elements point to the same conclusion that they have been 

 buUt up from the same kind of matter ? Might it not 

 also be possible on further investigation to find relations 

 which have not yet been recognized between the diS"erent 

 groups of the so-called elements ! It appears to me that 

 there is a law, as yet not recognized by chemists, having 

 some connection with temperature, in accordance with 

 which law these so-called elements are built up from one 

 and the same kind of matter. W. H. Cook. 



THE BRITISH TRAP.DOOR SPIDER. 

 To the Editors of Knowledge. 



SiBs, — In connection with the extremely interesting life 

 history of Ati/pus piceiis sul:., the so-called trap-door spider 

 of Britain, by Mr. Fred. Enock, in your November and 

 December, 1897, issues, it may interest some of your 

 readers to know that the Hastings colony is no longer 

 nameless from the want of a mature male. On 

 October 17th, 1897, I accidentally discovered the colony, 

 and on the 31st obtained a mature pair, since determined 

 by the Eev. O. Pickard-Cambridge to be Atypu.s piceu.i 

 suh., the same unfortunately as all the other known 

 colonies in Britain. I have since found several strong 

 colonies in this district, widely distributed, but all 

 A, picetis. 



52, Tackleway, Hastings. H. G. Jefferv. 



THE URANIA STERNWARTE. 

 To the Editors of Knowledge. 



Sirs, — I think the following extract wUI be of some in- 

 terest to those of your readers who desire to see established, 

 either in the metropolis or in some other large town of 

 England, a liimilar institution to that now existing at 

 Berlin, vir.., the Urania Sternwarte, an institution referred 

 to in Knowledge for September, 1897. I may add that 

 I came across this extract quite accidentally, shortly 

 after reading Mr. Lavalette's letter on this subject in 

 Kno\^xedge for August, 1897. 



The following is the extract, which was in the Penny 

 ^[a^|f1zinc for September 25th, 1833. 



'•PrBLlc Obsehtatort. — A correspondeut, who signs himself 'A 

 Man of Kent,' says ; ' Last week, for a shilling, I was able to make 

 acquaintance with an aquatic world whose existence I, till then, had 

 never been aware of. The "hydro-oxTgen microscope " convinced me 

 that a dewdrop may be as full of moving beings as Almack's. But I have 

 been ail my life, or half my life — that is, all the nights of it — desiring 

 a nearer acquaintance with the stars ; and I wish that my honest 

 shiDing C3ultl procure me admission to some observatory, where I 

 could contemplate those enormous evidences of the Creator's power 

 with as much ease as I did the minute atoms whose existence I had 

 never known of before.' The hint appears to us well worthy the 

 attention of those who have capital and enterprise. We have little 

 doubt that the prevailing desire for knowledge would render a cheap 

 observatory one of the most attractive objects in the metropolis." 



If, sixty-four years ago, such an opinion was expressed, 

 bow much more now is there need for such an observatory ! 

 Ivo F. H. Cabr-Gregg. 



