466 
NATURE 
[Sep¢. 17, 1885 
stellar point situated near the central region of the nebula. 
It is quite free from any blurred appearance or any aspect of 
indefiniteness other than that introduced by the nebula on which 
it is projected. 
On later nights the star seemed to have slightly decreased ; its 
light was feebler and less sparkling, but I made no exact com- 
parisons for tracing the decline of brilliancy, if any. 
During many years the naked eye appearance of this con- 
spicuous nebula has been familiar to me, and I have been 
accustomed to notice it particularly while engaged in prolonged 
watches for shooting stars. No sharply-defined nucleus was ever 
perceptible, but now the involved star is distinctly visible by 
slightly averting the vision, When the air is very clear the 
glowing out of the star now and then is very obvious, and I 
mention the fact in proof that the variation of the nebula by 
this new phenomenon is sufficiently great to affect its naked-eye 
aspect. W. F. DENNING 
Bristol, September 13 
GEALERS HO LE EDI OR: 
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Red Rays after Sunset 
THERE have lately been seen here some remarkable examples 
of rose-coloured streamers radiating from the sun at an interval 
of from 20 to 30 minutes after sunset, particularly on the 3rd, 
5th, and 6th of this month. On the 3rd the appearance was 
especially striking, the contrast of colour between one very 
broad, vertical ray and the greenish-gray sky which separated 
it from its neighbours being most marked. 
That these rose-coloured rays are essentially identical with 
the diffused rose-tint observed on other occasions is evident, 
not only from the similarity of colour and of interval after sun- 
set at which they appear, but also from the occurrence of inter- 
mediate examples, in which the rays are so far and so broad that 
the radiate character is almost lost. 
It is, however, by no means so clear why the coloured tract 
of sky should be sometimes split into rays, and it is with a view 
to ventilate this question that I desire to call attention to the 
subject. 
I believe it is generally supposed that the dark spaces between 
the rays are due to masses of cloud intercepting the sun’s light, 
but there are difficulties in the way of this explanation which I 
have never seen met. 
It need hardly be pointed out that the matter (whatever it be) 
which reflects the red light must be at an altitude far above any 
such masses of cloud as could intercept the sun’s rays ; it could 
not otherwise receive and reflect those rays half an hour after 
the sun had set to the observer. But although above the level 
of the clouds, the reflecting matter would still be subject to 
interception of the sun’s rays by cloud at sunset, and in order to 
judge whether the phenomenon can be so accounted for it is 
necessary to consider what kind of horizon that would be behind 
which the sun would set to an observer at the altitude supposed. 
My impression is that the horizon as seen from such a height 
would te so distant that whatever the irregularities of cloud- 
surface forming it, it would be practically a level line, and that 
the most mountainous masses of cumulus-cloud would be 
insufficient to cast at that distance the enormous shadows which 
would be necessary to account for the rifts between the rays. 
Clifton, September 8 GEORGE F, BURDER 
Fireball 
A LARGE fireball was visible at Bristol and other places on 
September 11, at about 9h. 25m. p.m. It was described to me 
by several observers who approximately assigned its path as from 
Altair towards the western horizon. The sky was much clouded 
here at the time, with only Ist magnitude stars visible, but the 
light of the meteor appears to have been something astonishing. 
Mr. G. T. Davis, of Theale, near Reading, writes me that, 
when first seen there, the meteor was near B Ophiuchi, and 
seemed to describe a slightly curved path to the horizon, which 
it touched apparently under 8 Serpentis. It exhibited a greenish 
tinted disk with bright, white aureole around it, and left'no train. 
The aureole was at least 16’ in diameter. 
It will be desirable to collect further accounts of this fine 
meteor. The direction of its path suggests that it may belong 
to the same system as that of the detonating fireball of Septem- 
ber 14, 1875, which had a radiant point at a 348°, 6 o°+ (Tup- 
man). During the past fortnight I have observed a considerable 
number of shooting-stars, and one of the best radiant points is 
at a 346, 80° +, or 2° W. of that of Col. Tupman’s fireball of 
September 14, 1875. W. F. DENNING 
Bristol, September 13 
Pulsation in the Veins 
Ir Mr. Hippisley will refer to Landois’ text-book, vol. i. 
p- 196, he will find it there stated, on the authority of Quincke, 
that a venous pulse occurs on rare occasions, normally, in the 
veins on the back of the hand and foot, when the peripheral 
ends of the arteries become dilated and relaxed. But it is to be 
remembered that the very same phenomenon may obtain 
abnormally, owing to some pathological condition of the heart, 
as stenosis of the mitral orifice, or insufficiency in action of the 
mitral valve. Mr. Hippisley does not state in his letter whether 
the heart was in a healthy condition, or whether any lesion of 
that organ was present in those on whom his experiment was 
tried. J. W. WILLIAMS 
Middlesex Hospital 
«* Furculum” or ‘‘ Furcula ” 
Is there any authority for the use of furcu/wm for the os 
furculatorium of birds? I am told by a contributor to the 
Proceedings of this Society, whose phraseology I have ventured 
to interfere with, that ‘‘furcu/zm” has been employed by 
Balfour, Huxley, and Rolleston. Such may be the case, but it 
is possible that even these great anatomical writers may have 
erred in the use of a Latin termination. No dictionary that I 
have been able to refer to contains the word ‘‘ furculum.” 
The Zoological Society of London P. L. SCLATER 
THE BRITISH ASSOCIATION : 
Aberdeen, Monday 
HERE have been few meetings of the British Asso- 
ciation so crowded with papers in nearly all the 
sections. On Saturday several sections met which, unless 
under the greatest pressure, never meet on that day. 
Section D has been compelled to split up into three sub- 
sections, and probably most of the sections will have to 
meet on Wednesday morning. The social distractions 
have been much more numerous than usual, and we 
suspect have somewhat seriously interfered with the 
legitimate work of the meeting. As might be expected, 
the Music Hall was crowded on Wednesday evening last 
to hear the President’s address, which seems to have 
produced a great impression on the audience. 
It is being more and more strongly recognised that 
such pre-arrangements as those of Sections A and B 
ought to become general throughout the sections. The 
discussions in the two great sections, of which the pro- 
grammes have appeared in NATURE, have certainly 
excited great interest among real workers in physics and 
chemistry. It is to be hoped that a full abstract of these 
discussions will be placed on record, as otherwise they 
cannot have any great permanent results. Perhaps the 
most popular feature in the regular sectional work has 
been the reading of Sir John Lubbock’s paper on ants, in 
Section D, on I’riday. 
The number of entertainments, afternoon parties, ex- 
cursions, and cozversaztones is almost without precedent. 
The conversazione in the Art Galleries on Thursday last 
was in every way successful, though the place was over- 
crowded. The flower and fruit show and the illumina- 
tions outside reminded many of the South Kensington 
displays. It was satisfactory to notice that, thanks to 
