AvcusT 8, 1912] 
NATURE 
581 
LERGERS TO THE EDITOR: 
[The Editor does not hold himself responsible for 
opinions expressed by his correspondents. Neither 
can he undertake to return, or to correspond with 
the writers of, rejected manuscripts intended for 
this or any other part of Nature. No notice is 
taken of anonymous communications.] 
August Meteor-showers. 
Tue following meteor-showers become due during 
the month of August :— 
Epoch August 12, 4h. 30m., approximately fifteenth 
order of magnitude. Principal maxima, August 9, 
22h. 55m., and August 11, 19h. 15m.; secondary 
maxima, August 10, 12h. 45m., and August 11, 
11h. 25m. 
Epoch August 13, 2h. 30m., approximately seven- 
teenth order of magnitude. Principal maxima, August 
13, 7h. 50m., and August 15, 4h.; secondary maxima, 
August 14, th. 20m. and 13h. 15m. 
Epoch August 15, 8h., seventeenth order of mag- 
nitude. Principal maximum, August 16, 20h. 15m.; 
secondary maxima, August 15, 11h. 50m., 21th. 4om., 
and August 16, 1toh. 25m. 
Epoch August 20, 16h., seventeenth order of mag- 
nitude. Principal maximum, August 18, 16h. 30m.; 
secondary maxima, August 17, 8h. 5m., and August 
18, 6h. 4om. 
Epoch August 17, gh. 30m., third order of mag- 
nitude. Principal maximum, August 18, 20h. 30m.; 
secondary maxima, August 19, 14h. tom., August 20, 
12h. 45m., and August 21, toh. 25m. 
Epoch August 23, 16h., fifth order of magnitude. 
Principal maximum, August 22, gh.; secondary 
maxima, August 21, 23h. 1tom., and August 22, 
12h. 55m. 
Epoch August 23, 20h. 30m., twenty-fourth order of 
magnitude. Principal maximum, August 22, 
20h. 50m.; secondary maxima, August 20, oh. 35m., 
and August 23, 6h. 4om. 
Epoch August 25, 21h. 30m., approximately first 
order of magnitude. Principal maximum, August 25, 
8h.; secondary maxima, August 24, 5h. 1om., and 
August 25, 2h. 55m. 
Epoch August 29, 21th. 30m., fourteenth order of 
magnitude. Principal maximum, August 30, 5h. 30m.; 
secondary maxima, August 31, 3h. 55m. and 13h. 45m. 
Though the meteor-showers of August are somewhat 
numerous, yet, taken in general, they do not indicate 
great meteoric intensity, and this remark is true as 
regards the middle portion of the month, when the 
Perseid radiant is usually expected to be most active. 
The most noteworthy maximum in the early part of 
the month occurs on August 4, 2h. 5m., and other 
maxima of less intensity belonging to this period that 
may be particularised are those of August 4, gh. 55m. 
and 23h. 45m., August 8, 2h. 4om., and August 9, 
22h. 55m. During the middle period, August 10-20, 
maxima of note occur on August 13, 7h. som., August 
16, 20h. 15m., and August 18, 20h. 30m. There is 
considerable meteoric activity also on August 22 
and 25. 
Early Perseids should be in evidence on the nights 
of August 2-6, and there are rather weak maxima of 
these meteors on the nights of August 10-11. The 
conditions as regards intensity improve on August 
14-16, and the Perseid radiant may be found to be 
considerably, if not most, active on the night of 
August 16. Joun R. Henry. 
July 29. 
NO. 2232, VOL. 89] 
A Flower Sanctuary. 
THE ravages of plant-raiders, about which Mr. 
Perrycoste so justly complains in your number for 
July 25, are a serious and growing evil, and the 
deplorable effects are felt and seen in almost every 
accessible part of the realm. I am encouraged to 
hope that the case of the Cheddar pink is not so crying 
as that of some other plants, especially orchids and 
; ferns. It is far easier to grow the Cheddar pink from 
the seed which it produces so freely than to extract 
the roots thereof from its native limestone chinks. 
Let us hope that the plants Mr. Perrycoste saw offered 
for sale were grown for that purpose, just as white 
heather, once esteemed and hunted up as a rare 
emblem of good luck, is now grown in thousands by 
nurserymen, and hawked through the streets of 
northern towns at a penny a bunch. I do not know 
to which Thalictrum Mr. Perrycoste refers as suffer- 
ing from plant-stealers; fortunately the Welsh poppy 
(Meconopsis cambrica) has spread to many districts 
of the country, and is naturalised far and wide. 
In this matter, unluckily, botanists are among the 
worst offenders, for they reckon a herbarium specimen 
incomplete unless the root is taken away as well as 
the inflorescence and seed. HeErsert MAxweE Lt. 
Monreith, July 27. 
Contrast Colours in the Use of Zone-plates. 
THESE effects would never escape the notice of those 
who experiment with zone-plates, but perhaps they 
have not been previously recorded. 
A zone-plate is placed at 14 ft. from an electric 
glow-lamp; 6 ft. further on a red image of the fila- 
ment is formed, which is conveniently observed with 
a microscope eyepiece. As this is moved away from 
the plate there follows in view a continuous succession 
of images in all the colours of the rainbow. The 
chromatic dispersion extends along the general axial 
line through more than 6 ft. Whatever may be the 
colour of the filament, the groundwork of the circle 
of illumination assumes the complementary colour. 
{ is surprising to observe how strong is the yellow 
field impressed upon the eye, while the violet image 
is growing imperceptible. W. B. Crort. 
Winchester College, July 24. 
LORD MERSEY’S REPORT ON THE LOSS 
OD REE. “TI RANIG. 
CP BE proceedings of the Court, over which Lord 
Mersey presided as Wreck Commissioner, ex- 
tended over thirty-seven days of public sittings, 
at which ninety-seven witnesses were examined, 
a large number of documents, charts, and plans 
were produced, and a great mass of facts and 
evidence was accumulated in connection with this 
“formal investigation” of the circumstances at- 
tending the loss of the Titanic. On the basis of 
these materials Lord Mersey, with the aid of five 
assessors, has produced a report in which twenty- 
six questions formulated by the Board of Trade 
are specifically answered. These questions “deal 
with the history of the ship, her design, construc- 
tion, size, speed, general equipment, life-saving 
apparatus, wireless installation, her orders and 
course, her passengers, her crew, their training, 
organisation, and discipline; they request an 
account of the casualty, its cause and effect, and 
of the means taken for saving those on board the 
ship; they call for a report upon the efficiency of 
