|:^/r?7l9, 1877] 



NATURE 



531 



east side of the Cascade Mountains, every stage of gradation 

 may be traced from circular mounds, through ellipiic, long 

 elliptic, to ordinary erosion furrows and ridges. 



Mr. Wallace asks in conclusion whether so extensive and uni- 

 form a deposit could be due to glaciers alone, or is it necessary 

 to suppose submergence ? 



In answer I would say that nothing is to me more puzzling 

 than the drift deposits on the Pacific slope, and I suppose the 

 same is true everywhere. The prairies about Pugit Sound have 

 evidently been submerged during the Champlain ei och, and I 

 suppose the mound structure to have been formed after emer- 

 gence, and the exceptional perfection of the mounds in that 

 region may be due to this fact. But there is not the slightest 

 evidence of submergence in the mound region of Oregon. All 

 the high, bare, grassy, hilly, easein slopes of the Cascade 

 Mountains are covered evenly with a pebble and boulder drift, 

 graduating upwards into a finer top soil. From this surface-soil 

 are carved the mounds, which cover hill and dale so thickly that, 

 viewed from an eminence the whole face of the country seems 

 broken out with measles. This universal drift-covering, twenty 

 to thirty feet thick over thousands of square miles, I know not 

 what to call it, unless it be the moraine pro/onde of an ice- 

 sheet. Joseph Le Conte 



University of Cal., Oakland, Cal., March 6 



OUR ASTRONOMICAL COLUMN 

 Winnecke's Comet, 1877, II. — In a note by Prof. Winnecke 

 in M. Leverrier's Bulletin of April 13, it is remarked with respect 

 to the elements of the comet discovered by him on April 5, "a 

 great analogy exists between these elements and those of the 

 comets 1827, II., and 1852, II., and it acquires a certain import- 

 ance from the fact that the intervals are nearly equal." 



The second comet of 1827 was discovered by Pons at Florence 

 and Gambart at Marseilles, on June 20, and was observed at 

 Florence until July 21 ; the original observations will be found 

 in Astron. Nach., No. 128. The best orbit is by Heiligenstein. 

 The second comet of 1852 was detected by M. Chacornac at 

 Marseilles on May 15, and was observed at Vienna till June 8. 

 On the suggestion of d'Arrest, the elements were calculated by 

 Hartwig, without any assumption as to the eccentricity, and the 

 resulting orbit proved to be a hyperbola, which, as d'Arrest 

 remarked, rendered the identity of this comet with the second 

 of 1827, which had been suspected by several astronomers very 

 unlikely. Now, however, that a comet has made its apperrance 

 after a like interval with elements bearing a certain resemblance 

 to those of the comets of 1827 and 1852, it may not be without 

 interest to examine into the possibility of identity a little further. 

 The elements of the three comets may be taken to be as 



follow : — 



1827, ir. 1852, II. 1877, 11. 



T ... June 784 ... April IQ'SS ... April 18-14 

 IT ... 297° 3i'7 ... 280° o''6 ... 252° o'-Q 

 a ... 318° io'-5 ... 317° 8'-4 ... 317° 5l''3 

 i ... 43° 38'-8 ... 48" 52'-9 ... 56° 42' 7 

 q ... 08081 ... 0-9050 ... 0-9283 



The motion is retrograde. 



It is evident from a comparison of the three orbits that if they 

 applied to the same comet, great perturbation must have taken 

 place between the successive returns, the line of apsides in par- 

 ticular having considerably retrograded, and the inclination of the 

 orbit increased by several degrees. This suggests an examination 

 of the path of the comet near the nodes with respect to proxi- 

 mity to the orbits of the planets. 



Assuming the mean of the two intervals for the period of 

 revolution, we have 24-93 years, and for the semi-axis major 

 $•5338, and taking as sufficient for our present purpose the peri- 

 helion distance of 1852, the angle of eccentricity is 63° 22'-4. 

 Hence it will be found that the radius- vector at the ascending 

 node is i-ooo8, which is less than 0-013 from the orbit of the 

 earth ; but to bring the two bodies together at this point the 

 paisage through perihelion mubt take place about September 3, 

 which is not the case in any of the above years. At the oppo- 

 site node the radius-vector is 5-966, not so very much greater 



than the radius-vector of Jupiter in the same longitude as 

 to forbid the hope of finding a much closer approach. Accord- 

 ingly on calculating the distances at different points of the orbit 

 about the descending node, it appears on the assumption we 

 have made with regard to the period of revolution, that in helio- 

 centric longitude 139° the comet would be distsmt from the orbit 

 of this powerful planet only 015 of the eanh's mean distance 

 from the sun, and it would anive in this lonui'ud- ' .out 480 

 days after perihelion passage, and therefore at the end o 'Sep- 

 tember, 1828, and the middle of ugust, 1853, but at these 

 times the heliocentric longitude of Jupiter was about 232° and 

 265° respectively, and the planet was far removed from the 

 comet in both years. 



The case is a very curious 01 e and possibly unique of its 

 kind : similarity of elements at three epochs separated by very 

 nearly equal intervals, and on the assumption of a corresponding 

 period of revolution, a very near apparent approach to the 

 planet which so greatly disturbs the cometary orbits, yet action 

 to account for outstanding differences of elements, could not have 

 taken place on either occasion of the comet's passage through 

 the part of its orbit where'great perturbation would be looked for. 



A New Comet. — On Monday morning telegraphic intimation 

 of the discovery of a new comet by M. Borrelly on the evening 

 of the 14th reached England from Marseilles, and its position 

 was determined the same night at Mr. Barclay's Observatory, 

 Lejton. The place is thus given in M. Borrelly's telegram : — 

 April 14, at 9h. 30m., R.A. 16° 31', N.P.D. 34° 56'; daily 

 motion in R.A, + 120', in N.P.D. —50', On the i6lh the 

 comet was visible enough in a large-sized Berlin " Cometen- 

 sucher," but was not a bright object in such an instrument. 



Observations at Cordoba. — Dr. B. A. Gould, director 

 of the National Observatory of the Argentine Rcj.ublic at 

 Cordoba, writes with respect to several objects to which 

 allusion has been made in this column. Referring to /t 

 Doradus — after remarking that it was noted as S m. by 

 Lacaille, 6 m. by RUmker or Dunlop about 1825, and 

 8^ m. or 9 m. by Moesta, between February i860 and January 

 1865, Dr. Gould says : " Our observations of it here have been 

 on the following dates: — 1870, Dec. 27; 1871, Jan. 19, 30, 

 March 16, April 13 ; 1873, March 7, on which days it was 

 looked for in the work upon the Uranometry. Also it has been 

 observed with the meridian circle 1874, Jan. 12, 26 ; 1875, 

 Jan. 5, 9, II, 20; 1876, Jan. 5, Feb. 12, 14. Some difficulty 

 was experienced in recognising it on account of several other 

 stars of the same order of brightness being situated in its im- 

 mediate vicinity. The identification was confirmed, however, 

 as soon as the equatorial telescope was mounted. The estimates 

 of magnitude were from 8 to 8.^, but I tee no reason to believe 

 that it has changed since December 1870. * * Mr. Thome 

 estimated it as 8-3 m. last n'ght" (March 3). Dr. Gould 

 proceeds, " While writing, let me add a word regarding the red 

 star in Sculptor, mentioned in the same number of Nature. 

 This is one of the most intensely red stars which I kno->v in the 

 sky. But I should neither call it ' orange-red ' nor ' red purple,* 

 nor 'couleur rose,' but a brilliant scarlet. In such castj, how- 

 ever, different eyes bear different witness, and differe .t indivi- 

 duals express themselves very differently to commu licate the 

 same idea." Dr. Gould intends at the earliest opp atunity, to 

 obtain numerical values for this and some other star:, ijy means 

 ofaZohlner's colorimeter. The star to which we r:re alluding 

 is in R.A. ih. 21m. los, N.P.D. 123° 11' 48" for 187 [O, accord- 

 ing to observations at Cordoba. 



The cluster 7 Argus, respecting which Gillis repoilcd changes 

 since Sir John Herschel's observations, has been photographed 

 several times, and Dr. Gould adds that he has simil.irly eight 

 plates of r} Argus and its surrounding stars — of which a very 

 large number are secured upon the photograph by an exposure 

 of eight or ten minutes. 



