April 27, 1871 | 
NATURE 
53 

Islands, where it is a serious hindrance to the men em 
ployed in collecting the eggs of the Murre (Uria Brunnichii 
which breeds there in countless numbers. The traffic in 
their eggs between these islands and San Francisco alone 
- reaches annually the sum of between one and two thousand 
dellars. The egg-hunters meet at» one o'clock every day 
during the season (from May to July) with the exception of 
Sundays and Thursdays, and at a given signal, so that 
each may have an equal chance in gathering the spoil, start off 
for the most productive egging grounds. The gulls understand- 
ing, it would seem, what is to cccur, hover overhead, awaiting 
the advance of the men, who rush eagerly into the rookeries. 
The affrighted Murres have scarcely risen from their nests, before 
the gull, with remarkable instinct, flying but a few paces ahead 
of the hunter, alights on the ground, tapping such eggs as the 
short time will allow before the egger comes up with him. The 
broken eggs are passed by the men, who remove only those 
which are sound. The gulijthen returning to the field of its 
exploits, procures a plentiful supply of its fayourite food. Dr. 
Heermann says that he once saw thee gulls scientifically ap- 
proach a single Murre sitting on her egg. Two of them feign- 
ing an attack in front, the Murre raised herself to repel them ; 
instantly the third advancing from the rear seized her solitary 
egg from beneath her, and tlew off with the booty, the two 
first immediately following to claim their share. The egg was 
dropped and broke on the rocks, when a general scramble 
ensued between the three robbers for the valued prize. 
Amonc the plants which have received honour and religious 
yeneration among the Hindoos, the Doob-grass (Cynodon dacty- 
fon) holds a prominent place. Its usefulness, added to its 
beauty, induced them in their earliest ages to consider it the 
abode of a benevolent nymph, and it is employed in many of 
their religious ceremonies. It owes much of its honour to its 
great tenacity of life, being regarded as an emblem of immor- 
tality ; and the Veda celebrates it, under one of its names, in 
words which indicate its supposed mystic origin :—‘‘ May Durva, 
which rose from the water of life, which has a hundred roots and 
a hundred stems, efface a hundred of my sins, and prolong my 
existence for a hundred years.” The extreme rapidity of growth 
in this grass is here referred to, and it is stated that, by merely 
chopping it in pieces and sprinkling these on prepared ground, 
a verdant sward may be obtained in a few weeks. The Doob- 
grass is frequently introduced by name in the popular stories of 
the country, and the roots are esteemed medicinal. 
IN the northern district of Alaska the various grasses, which 
form an important portion of the vegetation, are woven into mats, 
dishes, articles of summer clothing, such as socks, mittens, and 
hats, by the Indians and Esquimaux, Mr. W. H. Dall states in 
his report upon the resources of that region, that in winter the 
grasses are neatly tied in bunches, and shaped to correspond with 
the foot ; they are then placed between the foot and the sealskin 
sole of the winter boots worn in that country. ‘‘ There they 
serve as a non-conductor, keeping the foot dry and warm, and 
protecting it from contusion to an extent which the much-lauded 
moccasins of the Hudson Bay men never do. In fact, I believe 
the latter to be, without exception, the worst, most uncom- 
fortable, and least durable covering for the foot worn by mortal 
man.” 
AMONG other South American districts reported on the point 
of being reworked are the Cinnaba mines of Santa Barbara in 
Huancavolico, in Peru, gold and silver mines in Cauca, and 
copper mines in Doepar, in Colombia or New Granada. 
THE Chilian Government has employed the Cavadonga war 
vessel, Captain Gormaz, on surveying duties. Her work begins 
at Ancud. 


THE TRANSITS OF VENUS IN 2004 AND 2012 ¥ 
WH ILE preparations are being made by astronomers of various 
nations for the observation of the approaching Transit of 
Venus over the sun’s disc in December 1874, it may be of interest 
to know under what conditions the pair of transits in the twenty- 
first century will take place. This consideration has induced me 
to make a careful calculation of the circumstances of the transits 
in 2004 and 2012, from M. Leverrier’s Tables of the Sun and 
Planet, which at present are extremely accurate, and which there 
can be little doubt will closely represent the phenomena to be 
witnessed in those years. The calculations have been made 
entirely by myself, but with every precaution to avoid error, and 
I have confidence in the results. 
The following are the resulting elements of the transit in 
2004 :— 
Greenwich mean time of conjunction in right ascension 2004, 
June 7d 20h 51m 28s°8. 
76 50 28°66 
+22 53 204 
+22 42 52°3 
Right Ascension of Sun and Venus. 
Declination of Sun . 
ay Venus . 
Tcrary motion in R.A, 4 SU 5 2 35°07 
” - . Venus . —I 47°40 
Morary motion in declination Sun . +0 13°00 
ee Oe Venus -9 43°83 
Semi-diameter . Sun . 15 45°74 
F p . Venus 28°75 
Horizontal parallax - Sun. 8-78 
oe Bee cena NAC 30°85 
Log. distance of Venus from the Earth . 9°46069 
Equation of time . 1m 15s°6 (additive to mean time). 
Hence, for the centre of the earth, 
Ki 1 I dy hi nies . 
irst external contact = June 7 17 3 43 at 115'0) 
from N. towards E,. c 
First internal contact = June 7 17 22 35 at 118'0| _. 
from N. towards E.  . A : < “ - or the 
Second internal contact= June 7 23. 5 40 at 214°6| tirect 
from N. towards E. 5 ° mart Se 

Second external contact=June 7 23 24 32 at 218°5 
from N. towards E.. 5 : 5 ‘ 
And / being the geocentric latitude, p the radius of the earth at 
any place,{ and A the longitude from Greenwich + FE, — W., 
the reductions for parallax will be obtained from 
Ist ext. cont. =June 7d 17h 3m 43s+[2 2198]p .sin /— [2°5932] 
-p.cosé, cos(A+176° 32’). 
Ist int. cont. =June 7d 17h 22m 35s +[2°2571]p .sin/—[2°5708] 
-p.cosZ. cos(A+182° 38’). ; 
2nd int, cont.=June 7d 23h 5m gos — [2°5090]p .sin 7+[24353] 
- p.cosdZ. cos(A+47° 17’). 
2nd ext, cont. =June 7d 23h 24m 32s —[2-4928]p .sin /+ [24631] 
-p.cos/, cos(A+54° 35’). 
For the Royal Observatory, Greenwich, I find :— 
dad h = m''s 
First external contact, June 7 17 9 56 
», internal op Ay 17 28 51 \ Mean times at 
Second internal ,, 23 3 24 Greenwich, 
»» external 5 | 23 22 15 
Therefore the entire transit will be visible at Greenwich. 
Similarly, the elements of the transit of 2012 are found to be: 
Greenwich mean time of conjunction in right ascension 2012, 
June 5d 13h 4m 44s°3. 
Right ascension of Sun and Venus . 74 31 11:9 
Declination of Sun a) h22rAOU2AT 
de Venus. . +2250 3°0 
Tlorary motion in R.A...... .. stint ay 95 2 34°67 
aS 4 Venus. — 3470 
Horary motion in declination. Sun , +0 15°23 
7 a" VENTS suis —O 45°37 
Semi-diameter...Sun. . 15 46°01 
» Venus 28°77 
Horizontal parallax...,........... Sun 8-76 
ms oe Venus. . 30°86 
Log. distance of Venus frm the Earth . 9°46042 
Equation of time . Im 19s’8 (additive to mean time). 
* ‘Note on the Circumstances of the Transits of Venus over the Sun’s 
Dise in the years 2004 and 2012.” From the Procecairgs of the Royal 
Society. 
