40 
NATURE 
[Vov. 10, 1870 


potash bulbs and weighed. Some results obtained by four different 
methods of estimating the carbon in iron and steel are given at the 
conclusion of the paper.—‘‘ On the Deter:nination of Phosphoric 
Acid,” by Mr. W. C. Williams. The author suggests a modifica- | 
tion of the process for separating phosphoric acid from the 
alkaline earths originally proposed by Reigsig. 


SOCIETIES AND ACADEMIES 
BrIsTOL 
Observing Astronomical Society.—Report of observations 
made during the period from Aug. 7 to Oct. 6, 1870, inclusive. 
Solar Phenomena.—Mr. Thomas G. E. Elger writes :—The 
magnificent display of solar spots observed in August was re- 
peated, though in a rather less striking manner, during Septem- 
ber. Between the 7th and 12th the spots were small, few in 
number, and mainly confined to the S. hemisphere ; on the 11th 
only three moderately-sized groups were visible. The immense 
group observed last month, and which was near the centre of the 
disc on August 30, was due at the E. limb about the 17th, but 
owing to unfavourable weather and absence from home, I did not 
notice it till the 24th, when it measured 2’ 45” x 1’ 50” without 
including the outlying penumbra which followed it ; its length 
on the 25th was 3/0". The penumbra of this group presented 
some remarkable features. It contained four large umbrz and 
many smaller ones ; on the preceding side it was thickly studded 
with minute dots of every shade from black to light brown, 
When examined with a power of 180 at 3" on the 25th, the 
entire group was evidently undergoing rapid and violent changes, 
the striation of the penumbra and the dark “spurs” and serrated 
edges of the umbra clearly indicating the cyclonic nature of the 
forces involved. The above group was preceded bya very long and 
narrow V-shaped spot, which occupied nearly the same position 
as a large spot observed in August. Several other groups were 
observed during the month, which presented mteresting details, 
but they were generally smaller than the August groups. The 
appearances exhibited by the large group described above, and 
indeed by most spots of a similar class observed this year, seem 
altogether opposed to the ‘‘deep excavation” theory of sun spots. 
—Mr. T. W. Backhouse, of Sunderland, reports ‘‘a very fine 
group of spots passed the sun’s centre in the northern zone on 
September 21; on Sept. 23, at 21" 15™, it contained two very 
long penumbrze, which were not widely separated ; the ¢ one 
was 74,000 miles long, and the f one 92,000! On the 25th, at 
194 45™, it was only 66,000 miles long, and the / penumbra 
was divided into two. Another very fine group, also in the N. 
zone, passed the sun’s centre on the 24th. The dimensions in 
miles of its chief spot were as follows :— 


Penumbra. Umbra. 
Date. Time. Length. Width. Length Width. 
Sept. 21 iH aoe 47,000 26,000 ‘11,000 
ye abt. 72,000 50,000 31,500 —— 
22 gh 25m 50,000 ——— 29,500 ——— 
23 ‘2rh 25m 63,00 = —— 9 —-— —— 
25 2h 30 abt. 70,000 -_ - 
On the 23rd, at 4" 4o™, I found it was divided into four, 
apparently by a violent current in the middle from / to /".— 
Mr. William T. Dunning, of Bristol, observed the large spot 
visible on September 21 ; with his 4-inch metallic reflector he 
could very distinctly see a black nucleus in the S part of the um- 
bra. It did not appear to be actually enclosed within the umbra, 
but was situated on the margin of the penumbra.— Mr. E. B. Kno- 
bel, of Burton-on-Trent, says that on Sept. 25 the large group near 
the centre of the disc measured 2! 54" by 1/ 44" ; on the 26th 
the two largest groups were equal in length to 2’ 44" and 2’ 
36" respectively, They were distinctly vistble to the naked eye. 
—The Rey. S. J. Johnson, of Crediton, writes that on September 
21, at 4" 30™, a power of 70 on a 23-inch O.G, showed penum- 
bre on, at least, 26 spots visible on the sun. On September 20 
“*seven spots were very large indeed, and arranged in five groups, 
each scattered over a large surface.” —Mr. Albert P. Holden, of 
London, referring to the large spot, says that on September 20, 
“when entering on the solar disc it appeared as an elongated spot 
with a bright arm stretching over half the umbra till it joined a 
projection on the N. side. It was followed by a large broken 
group of broken masses of various dimensions. On the 23rd, 
at 8 a.M., the chief spot had enlarged considerably, while the 
broken ones following it had very much decreased. The great 
spot was very nearly divided into two by a very broad arm 
i 

springing from the N.; the W. portion of the umbra being 
again subdivided by asimilar arm on the S. side. This last was 
on one side broken up very peculiarly, so that it presented the 
appearance as if a hanéful of bright~straw had been thrown 
carelessly upon it. The eastern portion of the umbra was 
crossed bya very bright curved streak, which was so bright and so 
clearly distinct right up to its edges as to appear more like a 
carved piece of silver. On the 24th, at 8 A.M., the broken mass 
before referred to as following the chief spot had almost dis- 
appeared, with the exception of one small spot and a small 
amount of penumbra. The great spot was also a little smaller 
and quite divided by the broadarm. A large crack appeared in 
this latter. Each of the two portions of the original spot were 
also divided by luminous bridges across them. On the 28th the 
appearance of the umbra was much the same, although the 
penumbra was entirely changed and a great narrow branch had 
projected S. to an immense distance. This great arm was dotted 
here and there with a few patches of umbra, The broken mass 
which had followed the great spot at its first appearance was 
now entirely dissipated. On the 29th the two portions of the 
original spot were widely separated and much contracted, and 
two spots to the S. which had hitherto been of very small size 
much increased in dimensions. The rotation of the solar orb 
then carried the spot out of sight. The principal fact impressed 
upon the mind by these observations is that a spot becomes: dis- 
sipated in consequence of its continual division and subdivision 
by the projection of luminous bridges across its various portions. 


DIARY 
THURSDAY, NoveMBER 10. 
Lonpon InsTITuTION, at 7.30.—Acoustics of the Orchestra: Dr. W. H. 
Stone 
Lonpon Maruematicar Society, at 8.—Annval General Meeting. Re- 
cent Kesearches on Quartic and Quintic Surfaces ; By Prof. Cayley.—Ihe 
Kefiring Pre-ident’s address. 
FRIDAY, NoveMbBeER 11. 
ASTRONOMICAL Society, at 8. 
MONDAY, NoveMBER 14. 
Lonpon Institution, at 4.—Chemical Action: Prof. Odling. 
TUESDAY, NoveMBkrR 15. 
ANTHROPOLOGICAL SocrETy, at 8.—Ubservations on the Condition of the 
Biood-Corpuscles in Certain Races: Dr. Rk. H. Bakewell —Tribal Affini- 
ties among the Aborigines of Australia: Mr. C. Stanilana Wake.—Descrip- 
tion of Australian Aborigines and Half-Castes, with Exhibition of Skulls: 
Dr. Robert Peel. 
Zo LuGicaL Society, at 9—On the Form and Structure of the Manatee 
(Manatus Americanus): Dr J. Murie.—Observations on the Salmonide 
in ‘Lasmania: Mr. Morton Allport.—On the Anatomy of Aidurus /udgens: 
Prof. Flower. ’ 
STATISTICAL SOCIETY, at 7.45.—On the Claims of Science to Public Recog- 
nition and Support, with Special Reference to the so-called “Social 
Sciences ’; Ir. Guy, F.K.S 
Royat GEOGRAPHICAL SOCIETY, at 8.30. 
THURSDAY, Novemeer 17. 
Linnean Society, at 8.—On the Passifioree : Dr. M. T. Masters.—On 
the,White-beaked Bottle-nose : Dr. James Murie. 
CuEmicat Society, at 8.—Mineralogical Notices: Prof. N. Story Maske- 
lyne and Dr. Walter Flight. 
Lonpon InstituTION, at 8.30.—Acoustics of the Orchestra; Wind Instru- 
ments: Dr. W. H. Stone. 


CONTENTS PAGE 
ScIENCE AND THE WORKING CLASSES - - » - «+ + + s «© « 5 w @t 
Huxcey's Lay SERMons . oo 4el oe eS SD 
FerNet’s ELEMENTARY Puysics. By Prof. W. Jack . - - +. + + 23 
OuR BOOKSHELF a ie eee en Ses oe 
LErTEeRs TO THE EpITOR :— 
Hypothesis regarding the Corona.—J. A. C. OUDEMANS . « + + 25 
The Fuel of the Sun.—W. Marttieu WILiiams, F.C.S. . 26 
The Cockroach —J. DuKie 6: bt on ae fe) diel” Sl 
Were Cockroaches known to the ancient Greeks and Romans ?— 
Rev. W. HOUGHTON! 3 02 SS ae Sa a, 
The Aurora Borealis —W. R. Grove, F.R.S,; J.R. Capron. . . 27 
Clouds —J« Jo-Murvny, EGS... 5 0. Se. 3.5 ee ey ee ee 
Extreme Seasons.—J. BLAKE. . . . «5 . «© » «© © oo 4 28. 
Cyclones,—J. M. Crapy be ses z Rip ity) 
Singing of Swans.—J. A. HJALTALIN. . . . «we eee es) 
State «id to Science.—Prof. BALFour STEWART, F.R.S. . - . . 29 
TueEory of NATURAL SELECTION FROM A MATHEMATICAL POINT OF 
View, By A. W. bennett. F.L.S. cs! chee. ie ee eS 
Tue ProFessorsHip OF NaTurat History, QuEEN’s CoLteGe, BEL- 
FAST TS: 651) Pie he ae le oe et ALD oS a NAT CR ORRCTEI Wier te ie erect a 
PircHer PLants. By G. B RuckToNn net ae ae ee 
SPECTROSCOPIC OBSERVATIONS OF THE SUN. By J. Norman Lockyer, 
Lo eee eee Se og oe ieee 5 34 
NOTES 1075s ia Soren ile Ae ee mn ta po) aire a soe 
Tue BRITISH AssoctiATION :—SECTIONAL PROCEEDINGS . 37—39 
SCIENTIFIC/SERIALS ©, \-< ho) 51) pIETS AIOE eT < aleuice) at os aa 
SOCIETIES AND ACADEMIES’ .9. «© e+ “+/+ s+ = = = «© « 6 40 
DIARY 6 sl 5 RR Sey ae te, nana ee 
3 
} 
+f 

