M. Stumpe's intrepid industry was further shown in disregard of customary "scamping" subterfuges. Expedients for abbreviation vainly spread their allurements; every one of his 2,108 equations was separately and resolutely solved. A more important innovation was his substitution of proper motion for magnitude as a criterion of remoteness. Dividing his stars on this principle into four groups, he obtained an apex for the sun's translation corresponding to each as follows:

Number of
included stars.		Proper motion.Apex.
Group""°°
I.5510.16to0.32R.A.287.4Decl.+42.
II.3400.32to0.64"279.7"40.5
III.1050.64to1.28"287.9"32.1
IV.581.28andupward"285.2"30.4

Here again we find a marked and progressive descent of the apex toward the equator with the increasing swiftness of the objects serving for its determination, leading to the suspicion that the most northerly may be the most genuine position, because the one least affected by stellar individualities of movement.

By nearly all recent investigations, moreover, the solar point de mire has been placed considerably further to the east and nearer to the Milky Way than seemed admissible to their predecessors; so that the constellation Lyra may now be said to have a stronger claim than Hercules to include it; and the necessity has almost disappeared for attributing to the solar orbit a high inclination to the medial galactic plane.

From both the Albany and the Bonn discussions there emerged with singular clearness a highly significant relation. The mean magnitudes of the two groups into which Prof. Boss divided his 279 stars were respectively 6.6 and 8.6, the corresponding mean proper motions 21".9 and 20".9. In other words, a set of stars on the whole six times brighter than another set owned a scarcely larger sum total of apparent displacement. And that this approximate equality of movement really denoted approximate equality of mean distance was made manifest by the further circumstance that the secular journey of the sun proved to subtend nearly the same angle whichever of the groups was made the standpoint for its survey. Indeed, the fainter collection actually gave the larger angle (13".73 as against 12".39), and so far an indication that the stars composing it were, on an average, nearer to the earth than the much brighter ones considered apart.

A result similar in character was reached by M. Stumpe. Between the mobility of his star groups, and the values derived from them for the angular movement of the sun, the conformity proved so close as materially to strengthen the inference that apparent movement measures real distance. The mean brilliancy of his classified stars seemed, on the contrary, quite independent of their mobility. Indeed, its changes tended in an opposite direction. The mean magnitude of the slowest group was 6.0, of the swiftest 6.5, of the intermediate pair 6.7 and 6.1. And these are not isolated facts. Comparisons of the same kind, and leading to identical conclusions, were made by Prof. Eastman at Washington in 1889 (Phil. Society Bulletin, vol. xii, p. 143; Proceedings Amer. Association, 1889, p. 71).

What meaning can we attribute to them? Uncritically considered, they seem to assert two things, one reasonable, the other palpably absurd. The first—that the average angular velocity of the stars varies inversely with their distance from ourselves—few will be disposed to doubt; the second—that their average apparent luster has nothing to do with greater or less remoteness—few will be disposed to admit. But, in order to interpret truly, well ascertained if unexpected relationships, we must remember that the sensibly moving stars used to determine the solar translation are chosen from a multitude sensibly fixed; and that the proportion of stationary to traveling stars rises rapidly with descent down the scale of magnitude. Hence a mean struck in disregard of the zeros is totally misleading; while the account is no sooner made exhaustive than its anomalous character becomes largely modified. Yet it does not wholly disappear. There is some warrant for it in nature. And its warrant may perhaps consist in a preponderance, among suns endowed with high physical speed, of small or slightly luminous over powerfully radiative bodies. Why this should be so, it would be futile, even by conjecture, to attempt to explain.—Nature.

ANIMAL ORIGIN OF PETROLEUM AND PARAFFIN.

R. Zaloziecki, in Dingl. Polyt. Jour., gives a lengthy physical and chemical argument in favor of the modern view that petroleum and paraffin owe their origin to animal sources; that they are formed from animal remains in a manner strictly analogous to that of the formation of ordinary coal from wood and other vegetable debris. For geological as well as chemical reasons, the author holds that Mendeleeff's theory of their igneous origin is untenable, pointing out that the hydrocarbons could not have been formed by the action of water percolating through clefts in the gradually solidifying crust until it reached the molten metallic carbides, as these clefts could only occur where complete solidification had taken place, and between this point and the metallic stratum a considerable space would be taken up by semi-solid, slag-like material which would be quite impervious to water. Under the conditions, too, existing beneath the surface of the earth, such polymerization as is necessary to account for the presence of the different classes of hydrocarbons found in petroleum is scarcely credible.