192 



NATURE 



\yune 29, 1876 



rendering a supposed good piece of metal quite brittle and 

 dangerous if trusted to do its ordinary duty, such accidents 

 happening as a rule in cold weather ? 

 June 24 WiLMOT H. T. Power 



Sagacity in Cats 



The following facts are curious : I should be glad if any of 

 your readers can inform me wliether anything of the kind has 

 been already noticed. I have a cat of half-Persian breed ; she 

 is about eight years old, and has always been remarkable for her 

 aversion to strangers, more especially to children. If children 

 have at any time come into the house where she was, she has 

 invariably decamped and secreted herself. She never could 

 bear to be handled or pulled about (which so many cats seem to 

 enjoy) by anyone but by her master. 



During the present year this cat has remained in Scotland ; a 

 few weeks ago my little boy went to reside in the house where 

 the cat is at present. This boy is just at that age when children 

 delight in pulling about everything they can get hold of : natu- 

 rally a cat was a perfect godsend to him. After a few days the 

 cat was seen to smell the child repeatedly ; she seemed to be 

 satisfied of his relationship, and since that time she follows him 

 about the house (a thing which she never did to anyone but her 

 master), rubs herself against him, and allows him to pull her tail 

 and ears and draw her about by the legs. 



Owens College, June 22 M. M. Pattison Muir 



OUR ASTRONOMICAL COLUMN 



Le Verrier's Tables of Saturn.— Vol. xii. of the 

 Annales of the Observatory of Paris, containing, in addi- 

 tion to his Tables of Jupiter, the more extensive Tables 

 of Saturn, was presented by M. Le Verrier to the 

 Academy of Sciences on the 5th of the present month. 

 To insure, as M. Le Verrier has explained, their accurate 

 and convenient application, the Tables of Saturn occupy 

 two-thirds more space than those of Jupiter, or 278 and 

 J 70 pages respectively, though their general form and 

 arrangement appears to be the same, and as those who 

 have seen the Tables of Jupiter will be aware, is materially 

 different from the arrangement of the Tables of Mercury 

 to Mars inclusive. The tables of Saturn represent exactly 

 the observations from Bradley to the present day. 



M. Le Verrier again mentioned that his theories of 

 Uranus and Neptune were complete, and susceptible of 

 being extended to an indefinite number of years. The 

 comparison of the theories with observation is already 

 sufficiently advanced to enable him to pronounce upon 

 their satisfactory agreement. 



36 OrHiuCHi. — It appears to have been somewhat 

 hastily concluded that this star, so remarkable for its 

 identity of proper motion, both as regards amount and 

 direction with the distant 30 Scorpii, is also a binary 

 system. So far the measures by no means bear out this 

 inference, and unless they are affected with unusual 

 errors it is not easy to explain them. For comparison 

 the following may be selected : — 



Herschel and South i822'52 Pos. 227-4 I^^s. 5*55 



Herschel i835'i9 ,, 223-5 ,, 4'88 



Dawes 1841-59 „ 219-3 ». 478 



Jacob 1846-21 ,, 216-2 ,, 4-66 



1850-62 „ 214-9 ,, 4'49 



1854-07 „ 214-4 • M 4'i3 



Barclay 1871-51 „ 210-6 ,, 501 



It might be supposed from these measures, that while 

 the angle has been slowly retrograding between the years 

 1822 and 1 87 1, the distance had diminished until 1854, 

 and is now on the increase, but on projecting the mea- 

 sures it will be seen that this would indicate a motion of 

 one star in a curve convex towards the other. If there 

 are material errors of observation, the real motion of the 

 companion may be rectilinear, or the change in angle and 

 distance may be caused by a slight difference in the proper 

 motions of the stars. Further careful measures, how- 

 ever, are yet required before any safe inference can be 



made, and more especially in latitudes where the star rises 

 to a greater altitude than in this country. Capt. Jacob's 

 comparatively small distance in 1854 is not supported by 

 the meridian observations at Greenwich, Oxford, and 

 Washington, from which we might conclude, it was nearly 

 one second greater than his result, but meridian obser- 

 vations are not always reliable for such delicate com- 

 parisons, and besides it seems hardly probable that so 

 practised and excellent an astrometer as Capt. Jacob 

 would be in error \" in the distance of so easy a star, 

 favoured as he was by his positions at Poona and 

 Madras ; Secchi also is confirmatory. The statement of 

 Chr. Mayer that the companion was 1 3"-2 due S. of the 

 principal star, or on an angle of 1 80° (not 360° as given by 

 Smyth in the " Cycle "), does not assist an explanation. 



Nova Ophiuchi, 1848. — This star has been a difficult 

 object for the generality of telescopes during the last few 

 years. In 1856 it had descended to the eleventh magni- 

 tude ; ten years later it was a faint twelfth, and in 1874-75 

 not higher than thirteen in the scale in ordinary use. 

 Herr Julius Schmidt carefully examined the vicinity at 

 Athens in August 1867, fixing the positions of the small 

 stars near the variable, which were discernible in the 

 6-feet refractor of that observatory. These places are 

 here brought up to the beginning of the present year, 

 with the view to facilitate the recognition of the object 

 which became so suddenly conspicuous to the naked 

 eye at the end of April 1848. The magnitudes are 

 Schmidt's. 



No. of Magui- RA. N.P.D. 



Star. tude. h. m. s. o / // 



1 ... II ...1652 3-9... 10246 I 



2 ... 13 ... 16 52 28-7 ... 102 44 4 



From the first 

 Radcliffe Catalogue. 



Nova . . Var. ... 16 52 33-1 ... 102 42 3 j 



3 ... II ... 16 52 55-4 ... 10249 12 



4 ... II ... 16 53 25 ... 102 34 I 



5 ... loii ... i6 54 19-8 ... 102 49 6 



The ninth magnitude, Lalande 30853, R.A. 1876-0, 

 i6h. 52m. 18 5s. N.P.D. 103° o' 24", may be used to 

 identify the variable which it precedes 146 seconds, and 

 is 18' 21" more southerly. Schmidt thought there might 

 be a star 13" 14, following the variable 5s. or 6s. His 

 stars (i) and (3) had these position-angles and distances, 

 while Nova was still visible without the telescope in 

 1848. 



(i) Position ... 249-4 Distance ... 475-4 

 (3) M •• 144-5 M ••• 530-8 



The star (2) was repeatedly measured in position and 

 distance in 1848, with the 15-inch refractor at Harvard 

 College by the Bonds, with the view to discover if there 

 were appreciable parallax in the variable ; it is called a 

 fifteenth magnitude in the Harvard scale, and by a mean 

 of ten nights' measures its position was 2i2"-ii, and dis- 

 tance ii5"-65 for 1848*52. 



Stephan's Comet, 1867 (I). — This comet, for which 

 Mr. Searle found an elliptic orbit, period 33*62 years, or 

 almost precisely that of the comet of the November 

 meteors, and which was shown some years since to make 

 a very near approach to the orbit of the planet Uranus, 

 appears also to pass at a short distance from that of 

 Mars. In heliocentric ecliptical longitude 8i° 53', and 

 latitude •\- 1° 5', with true anomaly, 6° 10', the distance 

 between the two orbits is only 0*0207, thus affording a 

 similar instance of close approximation to this planet 

 which Dr. Briinnow found to take place in the case of 

 De Vico's comet of short-period. It is singular that a 

 comet's orbit should lie so very near to the orbits of two 

 of the planets, in one instance near its perihelion, and in 

 the other not far from aphelion. 



The Comet of 1698. — In the first orbit of this comet in 

 the last Astronomical Column, the perihelion passage 

 should be dated October. 



