FeBruary 26, 1914] 
regard to his remarks about the lava flows from a 
crater, though I am by no means an authority upon 
this subject, such as Dr. Johnston-Lavis, I would 
beg to point out that the lava from the crater of 
Skaptar Jokul in the year 1783 formed two main 
streams which flowed for a distance of forty to fifty 
miles each, and varied in thickness or depth from 
600 to 1000 ft. Now I cannot help thinking that such 
streams, only so much bigger, might have flowed 
from the craters of the moon, and it is well known 
that enormous floods have issued from volcanoes in the 
Sandwich Islands without much eruption of recky, or 
pumaceous débris, which might hide the effect of the 
lava, as Dr. Johnston-Lavis suggests, though Prof. 
Pickering puts forward the suggestion that it is some 
material, such as pumice, which we see in the moon’s 
rays. Apart from which geologists tell us that appar- 
ently in prehistoric times lava seems to have issued 
from vertical fissures, and deluged large areas, as is 
well seen in the great basalt plain of Snake River, 
Idaho, North America. Assuming that these fissures 
were caused by the contraction of the earth’s outer 
crust when cooling, and again comparing the moon 
with the earth, we at least come to Nasmyth’s well- 
known theory as regards these ray systems, though 
the manner in which these peculiar phenomena radiate 
from the craters still seems to suggest to me the 
same actions which took place from Skaptar Jokul, 
and in the Sandwich Islands. However, assuming 
Dr. Johnston-Lavis to be correct in his objections to 
this theory, I should like to know if he considers 
Nasmyth’s theory any more likely to solve this in- 
teresting problem? 
Then with reference to the meteorite theory, it 
seems to me that this scarcely satisfies all the objec- 
tions. In the first place, these rays are in many cases 
as wide as ten to twenty miles, and of avery consider- 
able length, and it would take a meteor or other body 
of excessive size to cause such markings, apart from 
which the speed would have to be truly prodigious, 
and, however horizontally the object was approaching 
the lunar surface, the gravitational attraction, though 
comparatively slight, would tend to divert the path 
into a vertical one to some other portion of the sur- 
face. Again, it is a curious coincidence that by far 
the greater number of these rays radiate from the 
principal craters, and if the meteorite theory is correct, 
how is it they crossed such a huge-walled crater as 
Clavius without apparently breaking down its walls, 
though leaving their marks? The rills and clefts 
certainly lend themselves to this theory, though when 
we consider the Sirsalis cleft, 300 miles long, and that 
there are no fewer than forty in the interior of Gas- 
sendi, it becomes difficult to explain even these. 
I certainly agree with Dr. Johnston-Lavis, that a 
practical astronomer with a high-power instrument 
ought to collaborate with a thoroughly practical vul- 
canologist, when perhaps some satisfactory explana- 
tion would be arrived at. Until then, I am afraid 
things will have to remain as they are. 
C. Hupert Prant. 
Lichfield Road, Walsall, February 10. 
The Discovery of Australia. 
In a note in Nature of November 27, 1913 (p. 379) 
relative to the Houtman’s Abrolhos Islands, the re- 
mark is made:—‘tThe wreck of the Dutch East 
India Co.’s ship, the Batavia, under the command of 
Capt. Pelsart, in 1629, is said to have led to the 
first recorded discovery of Australia.” 
Without entering into the vexed question of who 
first discovered Australia, I may point out that there 
are records of more than a dozen visits of Dutch 
ships and one English shiv to the northern and 
NO. 2313, VOL. 92] 
NATURE 
715 
western coasts of Australia before 1629. In fact, the 
general outline of the whole of the present State of 
Western Australia and of the Gulf of Carpentaria 
was known to the Dutch before that date. 
The Abrolhos Islands were discovered by the ships 
Dordrecht and Amsterdam, under the command of 
Frederik de Houtman, whose name they still bear, in 
1619 (vd. Heeres, “‘The Part Borne by the Dutch in 
the Discovery of Australia”). They were rediscovered 
by the ship Tortelduif in 1624, and the East India Co. 
recognised their danger to navigation, and had accord- 
ingly issued warnings to the commanders of all its 
vessels before Pelsart sailed from Holland. 
From a scientific point of view the wreck of the 
Batavia is of most interest, because it led to the 
discovery of the first member of the kangaroo family, 
viz., the Dama Wallaby, Macropus eugenii, which is 
plentiful on the two largest islands of the group. 
As it is generally supposed that the first discovery 
of the kangaroo was made by Sir Joseph Banks on 
Captain Cook’s first voyage in 1770, I think that 
zoologists may find Pelsart’s account of this smaller 
species, written nearly 150 years earlier, of interest. 
He says :—‘‘ We found in these islands large num- 
bers of a species of cats, which are very strange 
creatures; they are about the size of a hare, their 
head resembling the head of a civet-cat; the fore- 
paws are very short, about the length of a finger, on 
which the animal has five small nails or fingers, 
resembling those of a monkey’s forepaw. Its two 
hind legs, on the contrary, are upwards of half an 
ell in length, and it walks on these only, on the flat 
of the heavy part of the leg, so that it does not run 
fast. Its tail is very long, like that of a long-tailed 
monkey ; if it eats, it sits on its hind legs, and clutches 
its food with its forepaws, just like a squirrel or 
monkey. 
“Their manner of generation or procreation is 
exceedingly strange and highly worth observing. 
Below the belly the female carries a pouch, into which 
you may put your hand; inside this pouch are her 
nipples, and we have found that the young ones grow 
up in this pouch with the nipples in their mouths. 
We have seen some young ones lying there, which 
were only the size of a bean, though at the same 
time perfectly proportioned, so that it seems certain 
that they grow there out of the nipples of the 
mammez, from which they draw their food, until 
they are grown up and are able to walk. Still, they 
keep creeping into the pouch even when they have 
become very large, and the dam runs off with them 
when they are hunted.” W. B. ALEXANDER. 
The Western Australian Museum and Art Gallery, 
Perth, Western Australia, January to. 
DAILY SYNOPTIC CHARTS OF 
THE NORTHERN HEMISPHERE AND 
ABSOLUTE UNITS. 
N January 1 of this year, as already men- 
tioned in the Notes of the issue of Nature 
for February 5, the Weather Bureau of the United 
States commenced the issue of a daily weather 
map of the northern hemisphere, compiled from 
observations received daily at Washington by 
telegraph. 
In addition to the regular reports from the 
United States and Canada, represented in the 
well-known daily weather map of the bureau, 
reports are obtained from upwards of forty 
stations, which are sufficiently distributed in lati- 
tude and longitude to form the basis of a chart 
of isobars and isotherms for the northern hemi- 
