Fuly 29, 1886] 
Some meteorologists have asserted that the south-west mon- 
soon may be considered a stationary cyclone. This might beso if 
we define a cyclone simply as an irregularly circular area of low 
pressure round and into which the wind blows spirally. But 
when we look at the kind of rain and varieties of cloud which 
give distinctive character to various parts of a cyclone, our own 
observations and the information we have received from others 
entirely discountenance this idea. 
In Malaysia, between Singapore and Borneo, in the early 
days of April the surface-winds were all from about north-east, 
and the clouds at various levels always from more south of east. 
In North Borneo, later in the month, the south-west land breeze 
of the morning always went round by south-east to north-east 
in the afternoon and evening, while the higher clouds came 
always from about north-east. 
In Sooloo and the Philippines during the month of May the 
surface winds were much complicated by land and sea breezes, 
but the sequence of upper currents was always that proper to 
the hemisphere. 
So far for ordinary weather. I was not fortunate enough to 
meet with a typhoon, but the reports of the observatories at 
Manilla, Hong Kong, and Tokio are all agreed that the relation 
of upper and lower currents is the same in a typhoon in the 
China Seas as in a European cyclone. 
Yokohama, June 12 RALPH ABERCROMBY 
Mock Sun 
I INCLOSE sketch of the first mock sun I have been fortunate 
enough to see at Cranbrook, Kent, on July 20, 5 to 54 p.m. 
About Iom. before noticing this fine phenomenon we had 
noticed a fragment of it, not knowing what was to follow ; and 
we were struck by the extraordinary position of the bow with 
reference to the sun, viz. about 45° from it, and at an unaccount- 
able angle to the horizon. The latter picture I can only draw by 
memory. ‘The upper drawing is from one made on the spot in 
presence of two intelligent adult witnesses, who were consulted 
on each point which I proceed to notice. 
(1) The rainbow near the zenith was of the breadth and _bril- 
liancy of an ordinary rainbow (the same was the case with the 
fragment seen ten minutes earlier, which was lost when the rest 
came out). The fact of the arc seen near the zenith belonging 
to two circles, one small and one large, touching each other, 
was sufficiently certain to my eye, confirmed by another educated 
eye, but not admitted by the third less educated one. I draw 
it as I apprehended it. The colours were unusually vivid against 
a thin veil of fleecy clouds. 
(2) The halo-circle round the sun, and the arched eyebrows, 
so to call them, were about half the breadth of the rainbow, 
and washy in colour. The shapes drawn are quite faithful, and 
were so sharp as to leave no room whatever for doubt or 
Imagination. 
(3) The interior area of the circle was darker than the ouside. 
(4) The position of the mock sun was not diametrical. The 
sun, seen through a handkerchief whose edge was stretched 
through the two mocks, was about two-thirds of its own breadth 
below the edge, clear. 
(5) The white rays (about half the breadth of the mock lights) 
were seldom seen both at the same time, but were quite decided 
outside the circle and traceable within it, but nowhere nearly so 
bright as the mock lights. 
(6) The mock lights were short fragments of arcs of rainbows, 
more vividly coloured than the halo-circle outside of which they 
stood clear of it, but not so broad and not quite so vivid as the 
great rainbow arc. 
These fragments were wof tangential. Short as they were, 
their own axis was clearly determined by all three witnesses to 
be inclired towards the radial ray, and more inclined to the 
arc of the halo. But I have unconsciously given a curved shape 
to the short fragment. It was too short to show a curve. There 
was no pretence of a disk, as if really a mock sun. It was only 
a very vivid fragment of a rainbow. A third fainter one was 
at the top of the halo. 
The sky was much covered with thin cirrus ; a fine sunny 
evening ; air peculiarly clear for distant views. 
Collingwood, July 22 W. J. HERSCHEL 
P.S.—Radius of halo-circle, measured as best I could, 224° 
+ 23°. Radius, continued to the rainbow, 45° with propor- 
tionate error. The arc of the halo-circle was generally absent 
next to the mock lights, but could sometimes be traced. 
NATURE 2 
co 
\o 
“The Duration of Germ-Life in Water” 
IN a letter bearing this title in your last issue (p. 265) Mr- 
Downes refers to the recent publication by Messrs. Crookes» 
Odling, and Tidy, of some experiments which they have made 
on the vitality of the Bacillus anthracis in water, with regard to 
which I should like to call attention to the fact that this sub- 
ject has during the past three years been investigated by various 
experimenters, including Koch, Cornil, and Babes, Nicati and 
Rietsch. Within the past two months no less than three papers 
have been published on this subject, two of them in Germany by 
Dr. Wolfhiigel and Meade Bolton respectively, whilst the third, 
by myself, ‘‘On the Multiplication of Micro-organisms,” was 
communicated to the Royal Society at the meeting in June last. 
In this paper I have recorded a number of experiments made 
both with the mixtures of organisms found in various natural 
waters, as well as with three well-characterised forms which are 
associated with disease, viz. Koch’s ‘‘Comma”’ spirillum of 
Asiatic cholera, Finkler-Prior’s ‘‘Comma” spirillum of European 
cholera, and the Bacillus pyocyaneus, which produces the 
greenish-blue colouring matter frequently present in abscesses. 
The methods of research which have been independently se- 
lected both by Wolfbiigel, Meade Bolton, and myself, are 
identical, and consist in the examination, by gelatine plate- 
cultivation, of waters purposely impregnated with the organisms 
in question. This method is obviously the one which most 
recommends itself for the purpose, as it not only enables one to 
ascertain the presence or absence of the organisms, but also to 
quantitatively follow their multiplication or reduction. I may 
mention that these three organisms present great differences in 
their behaviour under similar circumstances; thus the Baczllus 
pyocyaneus is possessed of far greater vitality in water than either 
of the other two, its presence being demonstrable even in dis- 
tilled water after fifty-three days, in numbers exceeding many- 
fold those originally introduced. Koch’s ‘‘Comma” spirillum, 
on the other hand, was in the purest forms of potable water no 
longer demonstrable after the ninth day, whilst in London 
sewage it was found in largely multiplied numbers after twenty- 
nine days; whilst Finkler’s spirillum could in no case be 
detected after the first day, and frequently not even on the day 
of inoculation. A curious phenomenon, which my experiments, 
as well as those of Wolfhiigel and Meade Bolton have brought 
to light, is that when organisms of this kind, which are not the 
natural inhabitants of water, are introduced into this medium, 
a large proportion of them are frequently at first destroyed, a 
greater or less multiplication in their numbers often subsequently 
taking place. 
The Aactllus anthracis, as is well known to bacteriologists, 
appears in two very distinct forms, the Jacz//ws-form and the 
sfore-form, and these present very great differences in their 
powers of endurance, the former being destroyed with compara- 
tive ease, whilst the spores are remarkable for their vitality. 
Mr. Crookes and his colleagues have apparently experimented 
with the bacillus-form of anthrax only, which they state is rapidly 
destroyed when introduced into London water, but Dr. Meade 
Bolton, who has dealt with anthrax in both its forms, has shown 
that the spores of anthrax retain their vitality even in distilled 
water for upwards of ninety days, and that it is only the bacilli 
which rapidly perish in some kinds of potable water. In pol- 
luted well-water Meade Bolton has also shown that even the 
bacilli are persistent for upwards of ninety days, and the spores 
for nearly a year, whilst Wolfhiigel has found that in polluted 
river-water (the River Panke, in Berlin), even when diluted ten- 
fold with distilled water, the anthrax bacilli undergo extensive 
multiplication. Percy F, FRANKLAND 
Normal School of Science, 
South Kensington Museum, S. W., July 26 
Animal Intelligence 
In Nature for July 22, on p. 265, Mr. Frederick Lewis calls 
attention to a nest-building wasp who closed up her nest without 
filling it first with grubs or laying an egg. There is nothing 
uncommon in this neglect on the part of the wasp, as any one 
who has at all studied their habits in the tropics will know, such 
perfectly empty nests being frequently met with. I have 
often thought the empty nest might have something to do 
with the fact that the wasp may not have been prepared to 
deposit her egg; but then, if that were the case, we should 
occasionally find nests with the remains of the caterpillars or 
