January i8, 19 12] 



NATURE 



\hg 



obscrsed a certain sparkling flocculence which I interpreted 

 ID be a dissipation of the ring." 



Commenting on this message, the Rev. T. E. R. Phillips 

 stated that he had observed Saturn the previous night, but 

 had failed to note any extraordinary feature such as was 

 described in Pf-of. Todd's message ; it was, however, 

 possible that the affected section of the ring was not then 

 in view. He also added that, according to the accepted 

 viiw of the constitution of the rings, disturbances of some 

 kind were likely to occur from time to time, and that these 

 might be revealed by irregularities in the shape of the 

 shadow of the ball on the rings. At the previous appari- 

 tion he had seen such irregularities, but recently he had 

 thought the shadow perfectly uniform. Other observers, 

 who had been able to see the Encke's division easily, had 

 also noted nothing irregular or unusual. 



.\ Daily Mail inquiry at Greenwich elicited the sugges- 

 tion that the phenomenon may have been produced by the 

 collision of two of the particles forming the ring, the heat 

 Itinerated by the impact possibly raising the particles to 

 incandescence. Owing to the comparatively large separa- 

 tion of the particles and their uniform motion, such 

 collisions would not be of frequent occurrence. 



-Mars. — Numerous observations made at the S^tif 

 Observatory are recorded in No. 4545 of the Astronomische 

 Nachrichten. Among other things, the disappearance of 

 ihc south polar spot since December 13, 191 1, is noted, and 

 it is remarked that its position was occupied by a large, 

 well-marked area having the same hue as the southern 



inlands." Special attention has been paid recently to the 

 study of Libya, which M. Jarry-Desloges considers 

 important in the study of abnormal clear places on Mars. 

 He gives details of observations showing changes in the 

 brightness and tint of Libya during the period December 

 14-23, 1911. A telegram received on December 28, 1911, 

 states that the Thyle region had been abnormal since 

 December 18, being whitish with brilliant spots. The 

 Styx was observed double, and M. Tyrrhenum and Syrtis 

 .Minor were always vague. Telegraphing on December 30, 

 til-- same observer stated that considerable changes had 

 lakm place in the north polar cap during the preceding 

 i\\«ni\-four hours. An important white band was seen 

 iiiw.-n Propontis and Palus Maiotis, and M. Tvrrhenum 

 w.i^ extended over Eridania. On January 4 M. Jarry- 

 1 >i sloges announced the reappearance of the south polar 

 (ap. 



A \iw \'.\Ki.\Bi.E OR Nova, S7, 1911, Persei. — Mr. 

 ( i\. 1 )'I',>i.rrr, in a note appearing in No. 4545 of the 

 .l^lnninnu.ulii' .\ dchrichten, describes his observations of 

 an (ilij-M I in I'rrseus which would appear to be a new 

 \arial)li' star or a nova. On a pliniograph taken on 

 Xovr-nihir 13. 191 1, when the objei t was at its maximum 

 iirigliin.ss, about mag. 11-12, l\v iin.ig,- ,,f the newly dis- 

 iiivi-i-il \aiial)I(' (iverlapprd []\c images of two neighbour- 

 ing star-,, whereas il is noi shown ai .all on photographs 

 shdwing objects mucli fainl- 1- than ih-- . l.-vinih magnitude 

 t.iken with the sani'- instiiniiinl s (hniiiL; August, 191 i. 

 I h'- position of till' ohji'ct in t|ui-i!(in is 2I1. om. i3-is., 

 -r S>''' .i')>i' fur 1X550, and jh. ^in. i(i.,s., + 5(1° 42-8' for 



I in: l.ir.iii n\ (Umlis mii/i and iqiir. — In a note 



^q'p' .irin- in No. .)5.)5 of tln' .\ slroiiiniiisrhc Xiuil lifh hii 

 ^I. ()ilow (h'siaiss.-, ihi- v.ar\ing hrightiirss of Kies^^ 

 Hoii/i) ami Hnioks's (,ic,ii,) c (inirts. Adiniliing thai ih. 

 liii^L^hln.ss i, proportional to A-\ In- sreks lor ihr diff.r.ni 

 I "nuts tin- i'\piiniail of lli.' t|uanlit\ r. I'or Hrook's's 

 'iinicl, Iroui I Willi \ -Ihiir ohscrv.ations niadi' during 

 Au-usi ..•;- t,, 0, loh.r 15, hi- IiikIs that 1 S'l'- glvi-s iji',- 

 n'^ne-l .ap|)ro\inialion to thi' ohs.a-\i-il (ii|-\-.', II,, lin' 

 III. an hri<;hl n.s>, h.'ing 5^ 1 . 



i'ldiii twi-K- ohs.av.alioiis piihh.h.'d h\' l)i-. llol,|., h. k 

 li" iinds thai il„ 7... anil r ' an- 1 In ■ "v.alin s whi,h h. -I 

 M ih- hri-hlni-~ of Kir^.,", (oni'l. h'or 1 wo other conn-ls, 

 I'lMw ;in<! nM.Sr, h.- d-riv. s th,. xalu' - | 1 ,_ =5.4, r-*-\ and 

 II, i .,, (•' ■ ', ri-|)ii lively. 



1 in, >(,\..\R ('o\si\\i. -In No. 5, vol. xwiv., ol 77;, ■ 

 Astropliystcal jxtirunl PlJ. Very has ;ni .irliili- on tin- 



need of adjustment of the data of terrestrial meteorologv 

 and of solar radiation, and on the best value of the solar 

 constant. In it he criticises the recent work of Abbot and 

 Fowle in the determination of the solar constant, and 

 argues that while their methods purport to follow 

 Langley's methods, they have abandoned the essential 

 prn-K.-iple of the latter, and more nearlv approximate to 

 Pouillet's. Prof. Very argues that too 'low a value has 

 been assigned to the efTective depletion of the incident solar 

 rays, and consequently too low a value has been obtained 

 for the solar constant. Whereas the value of approxi- 



I mately 2 calories is given in the second volume of the 

 Annals of the Astrophvsical Observatorv of the Smith- 

 sonian Institution, Prof. \'ery finds evidence on ever\ 



i hand that the value should be greater than 3 but less 



! than 4 calories. 



THE SURVEY OF INDIA.' 



'P'HE report of the operations of the Survey of India 

 during the year 1909-10 ' has just been' issued bv 

 Colonel S. G. Burrard, R.E., F.R.S., the Officiating 

 Surveyor-General. During the year the new scheme of re- 

 organisation which had been approved was brought into 

 operation, and in it provision is made for three topo- 

 graphical circles, the northern, southern, and eastern, each 

 under a superintendent. Four topographical survey parties 

 are allotted to each, and there ari six trigonometrical 

 parties under the direction of the Superintendent of 

 Trigonometrical Surveys. Details are given of thr topo- 

 graphical work executed in each of the three cin l. s, .md 

 maps show, the distribution of the areas surveyed and the 

 portions which have been surveyed since October, 1905. 

 The forest surveys were carried out in almost every case 

 by the particular topographical parties in whose spheres 

 of work the forests lay, and were niainl\ on tlie scale of 

 2 inches to i mile. 



The principal triangulation was coniiiuied in the North 

 Baluchistan series, the Kashmir series, and in the Upper 

 Irrawaddy series, a total of thirty-five sta'tions being 

 observed from, and thirty-nine triangles being completed, 

 the average angular errors being 0-303", 0-591'', and 0-381" 

 respectively in the three areas of work. .A series of com- 

 parisons was carried out to test the accuracy of mercurial 

 barometers, aneroid barometers, and hypsometers as height- 

 measuring instruments. The result's showed that " the 

 aneroid barometers differed greatly from on-- anotli.r .uid 

 from the mercurial barometers. Tin- l.atn r u-iv- heigjus 

 in defect, and the hypsometers gax, hi ii^lns eonsi,!, r.ihh 

 in excess of those obtained by tri.Mignlaiion ; ih- . m . s., ai 

 16,000 feet being as much as (;oo 1..1. Asironomit al 

 latitudes were observed in Oudh, and ]» luhilum opi rations 

 were extended to the east and niiriii-i .isi ol thr .area in- 

 vestig.ated in the s.ason kioS o in Cmtral Inili.i, twelve 

 stations iiavini.; heen \isitr(l this \r.ar in th,- tr.iit situated 

 between lals. ^i' .ami .'1. \,, .iml lon-s. -,,' am! .S v' l'"-- 

 The m;ii;nilie sui\i\ .iml iIm lid.il ojMt.iiions \\,\i> con- 

 tinuid. 



.\l Dihra Dun ihr l.,is.-lini' ohs,r\,aloi\ w.is c oinnn need 

 in looo, anil its i amsi i m t ion is now in h.iml. .\ i onipji'te 

 apparatus ot wii's has h. ,11 juircliasr ij 10 [.plari' llii- old 

 compi'iis.at ion h.ais, .mil .ap|)ro\im.ili' sii. ., |or h.ise linis in 

 lun'ni.i and K.ahu iiisi.an h.i\i' h. in s, lieti d. Ih.- sinnil- 

 lani'oiis ii-duelion ol llf lf\.|lin;; was r, anplit . d during the 



sununir ot ; o 10 ; .ill 1 '. - 

 .■Hniin.ii.d, .mil ih.- l.\. I 1 . 

 nin.- dillii .lit poinis ; oil hi .. 

 and .adjii~l.(l values of .all '> 

 .mil loiiii wi-re ohlaiilid. I 

 \i\. ol ill.' ■ \i 1 inml I.! 

 I riL;onomi'lrii .1' Sui \ . \ ol 

 1 ills \ olmn.- ui.ti ks 1 h.- 1 Ills. 

 1. A'.lliii'^ \\ iM k in I ndi.i. thus 

 roiisi^l.ail ii.isis for till li \ . lliiu 



II. G. 1,. 



NO. 2203, VOL. 88] 



' The Gener.il Report on the Operatiuni of the Survey of Imli.-i during 

 the Survey Year 19119-10. Prepared under the direction of Colonel S. G. 

 Hurrard, K.E., F.R.S., Officiating Surveyor-General of India. (Calcutta, 

 1911.) Price a rupees or 3jr. 



