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28; Adria, on February 23; Abundantia, on November 1; an unnamed one, No. 155, on November 8, and Xanthippe, on November 22.

Finally, we have to record the discoveries (three in number) of M. Perrotin, at Toulouse. They comprise Tolosa, found on May 19, 1874; No. 149, on September 21, 1875, and No. 163, on April 26, 1876.

When at the beginning of the century, the first of the small planets was found, little was it imagined how large a number there really were; now of course the probability is that it is very great indeed. As may be supposed, the brightest were as a general rule picked up first, and the most recent discoveries are exceedingly faint.

The inclinations and eccentricities of the orbits are in general much greater than those of the large planets; the distances from the sun are very various, some being not much more than that of Mars, and others not much less than that of Jupiter Attempts have been made to test the old idea of Olbers that they might be fragments of a large planet, which had been separated by some explosion or other catastrophe; but as it did not appear that they could actually be traced back to any common point, that idea has been abandoned. The reflection that is principally suggested to us by the consideration of these discoveries and those of comets and meteoric streams, is what a wonderful collection of moving bodies is contained within our solar system. It has become a trite remark to call to mind with what unerring precision the motions of all these bodies can be calculated (when once the elements of their orbits have been accurately determined) in accordance with the Newtonian law of universal gravitation. But it may be not out place to remark that not only is this law no à priori truth, capable of demonstration like the theorems of Euclid, but one which the genius of Newton unravelled from the laws empirically deduced by Kepler from astronomical observations (chiefly those of Tycho Brahe); not only, we say, is this the case, but the law of gravitation, according to which every body in the universe attracts every other directly in proportion to the mass of the attracting body, and inversely as the square of the distance between the two, is capable of explaining the planetary and other motions of celestial bodies only by uniting it with the so-called laws of motion. These laws also are no part of the necessary constitution of matter, nor could they ever have been known by mere mathematical reasoning; our knowledge of them is due to observation, and the philosophical experiments by which Galileo established them, contributed immensely more to the progress of science than did his discoveries with the telescope. With much more force than Anaxagoras of old, can we feel that both the great and small bodies around us are moving under the control of mind or intelligence--the intelligence, indeed, of the Divine Mind, which has impressed upon matter those constant laws by which science teaches us that its motions are governed and directed.

ADDENDUM.-In view of the continued rapid progress of discovery of small planets, we have thought it desirable to append a table of those found during the last two years in the order of discovery. It is as follows:

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Although the excessive smallness of the mass of the members of the extensive group of minor planets prevents their producing any effect upon the motions of the larger bodies of the system, the reverse effect of the latter upon the motions of the small planets is, in certain cases when they come within a small distance of Mars or Jupiter, very sensible, and advantage has been taken of it to determine the mass of Jupiter, the largest and most powerful of all the planets. Professor Krüger of Helsingfors obtained, about three years ago, a careful determination of this kind from the planet Themis, which agrees well with those obtained by other methods, viz., by the motions of Jupiter's own satellites, and by those of Faye's comet. The labours of Dr. Galle have shown that some of the brightest of the small planets may be employed to confirm our knowledge of the sun's distance, of which important element he has recently obtained by observations of Flora, a value nearly the same as that which results from other methods. If, therefore, a selection has to be finally made amongst the small planets, those will be chosen for continued observation and accurate calculation of orbit which approach nearest to the large planets Mars and Jupiter, on either side of the group, as well as those which are the brightest, and probably of the greatest magnitude. W. T. LYNN,

19

PUBLIC HEALTH AND MORTALITY.

THE tempting picture of a city comparatively free from sickness, because totally free from defects as far as its natural position and its sanitary arrangements are concerned, has been placed before the public during the past year, and an effort will, it is said, shortly be made to prove by experiment the possibility of attaining the proposed end. Anything more absolutely desirable tha Dr. Richardson's Hygeiopolis it would be difficult to imagine, but to the practical mind it must be obvious that such schemes can at the most be but partially adopted, and that their chief benefit must lie in the evidence they afford by sheer force of contrast as to the advantages to be derived from the observance of what may be broadly termed the laws of health, and as to the possibility of escaping a large number of the ills to which man is popularly, but, as facts prove, very erroneously, believed to be the heir. In expressing the opinion that such schemes are unlikely to be speedily successful, we are far from wishing to imply that they are absolutely Utopian; rather we believe them to be far more capable of realization than the leaders of local government are inclined to imagine; but it is precisely because of the apathy of the majority of public bodies, and the almost equal negligence of individual householders that we regard any genuine reform as being inevitably a work of time, and even of several generations. That we have in sanitary matters advanced to a remarkable degree of late years all students of our national condition will gladly admit, and in the course of time education in this respect may be so far extended that cities where the public health is esteemed the first consideration may become more and more common, but for the present the value of such plans as that advocated by Dr. Richardson, must, as we have suggested, lie in the attention which they draw to a great and important subject rather than in any immediate and universal attempt to enforce the principles advocated by their promoters. And of precisely the same character as this effort to present in the concrete the ideal of a healthful town are the annual reports which are issued under the editorship of Dr. Farr from the office of the RegistrarGeneral of births, deaths, and marriages, and the reports which have for some years past been issued by Mr. Simon from the Medical Department of the Local Government Board. In Dr. Farr's returns, which perhaps receive from the newspapers more attention than is given to the publications of any other Government department, we have week after week, month after month, and year after year, masses of facts and figures, showing not only the numerical progress of the nation, but its growth or decadence in particular districts, and the causes which affect its well-being in one direction or the other in those districts; we see not only that babes are born, that men and women marry, and that young men and maidens, old men and children alike die, but we see

actually before us the reasons why these processes of nature are worked out more speedily in one place, or in one section of society, than in another, and, if men were wise, if they were willing to read between the lines, and to accept the lessons that were offered, they might to a great extent change the face of human life. From such records, dealing with humanity, not only in the aggregate, but at the several age-periods of life, under the different aspects of town and country existence, and even under the still more various conditions of the daily occupation which has so much to do, not only with health and happiness, but absolutely with the duration of life, we have a constant reflection of the picture which the nation itself is throwing on the great mirror of time, and as we look beyond its lights and shadows, we see at work the causes which, if rightly regarded, would enable us to disperse many a cloud, and to render many an existence brighter, purer, and in the highest sense better. There is, in fact, in the records thus placed before us, as in the stones under our feet, a sermon if we will but heed it, and those who turn aside from the blue book as a mere collection of figures, uninteresting as the share list in the daily paper to the reader who has no stocks, make a mistake which cannot too often be pointed out. If, indeed, Dr. Farr's vast tabular returns were of as little value as nine-tenths of the public imagine, judging by the slight regard that is paid to their teachings, the time and money expended on their production would be a gross waste. That the contrary is really the case is, however, easy of proof, and it would be well if the stern lessons which are here set forth of the results of neglecting the most elementary laws of life were brought home to those whose duty it is not only to guide, but to teach the people. That there is an urgent need for such teaching public men who are not only qualified, but honest enough, to tell the truth, do not hesitate to affirm, and Mr. Simon, whose recent retirement from the post of Medical Officer to the Privy Council and Local Government Board is deeply regretted by all true sanitary reformers, has more than once spoken out plainly on the subject. Writing in 1854, he said: "Except against wilful violence life is practically very little cared for by the law. Fragments of legislation there are indeed in all directions, enough to establish precedents, enough to testify to some half-conscious possession of a principle, but for usefulness little beyond this. The statutes tell that now and then there has reached to high places the wail of physical suffering. They tell that our law-makers to the tether of a very scanty knowledge, have, not unwillingly, moved to the redress of some clamorous wrong. But, tested by any scientific standard of what should be the completeness of sanitary legislation, or tested by any personal endeavour to procure the legal correction of gross and glaring evils, their insufficiencies, I do not hesitate to say, constitute a national scandal, and perhaps, in respect of their consequences, something not far removed from a national sin."

That this grave indictment was justified by facts when it was

written was amply proved, and has been proved over and over again in the twenty and more years that have since passed away, and although we have advanced, and are advancing, the need of the utilisation of the knowledge we possess is as urgent as ever, and the sources from which it can be derived are therefore well worthy of attention. Looked at, then, as something more than an aggregation of figures, we may find in Dr. Farr's reports, as in Mr. Simon's, matter which suggests not only thought but action; we may see in them the amplification of the great text "Sanitas, omnia sanitas," on which Mr. Disraeli once began to preach, and which, it may be hoped, will furnish Lord Beaconsfield with a basis for much useful practice; and even to the ordinary Englishman they present food for reflection and a ready means of judging how far he is liable to suffer from effects of which the causes are here laid bare to view, and how far those causes can be controlled by watchful care, or removed altogether by compulsory measures.

But while each annual report is valuable in itself, it is from the comparison of the figures of a series of years that the most trustworthy and useful deductions can be made, and to his twentyfifth annual report Dr. Farr has added an appendix, giving a most exhaustive series of tables showing the mortality in the registration districts of England during the years 1861 to 1870 as compared with a similar series of tables for the previous ten years. To this appendix we propose to direct the reader's attention. And, first, as a justification of the labour involved in the preparation of the work, we are supplied with certain facts to show that the knowledge gained from tables such as these is of vital importance. To take small-pox as an instance, after it had been learnt that a milder type of the disease could be induced artificially, fatal to few of the inoculated, the practice of inoculation was introduced in London, and was publicly performed in the years 1746 to 1763 on 3,434 persons at the Small-pox Hospital, only 60 of whom, it is said, died of the disease. But it was found that the deaths from small-pox in London, compared with the deaths from all other causes, and also the absolute mortality, increased considerably when inoculation became common, and subsequently it was made illegal. Then vaccination was introduced, and its benefits at once became apparent, for cow-pox, unlike small-pox was completely innocuous. From 1771 to 1780 small-pox caused 100 out of every 1,000 deaths in London, but from 1831 to 1835 it only caused 27 in every 1,000, while in 1861 to 1870 the number was reduced to 11. But, in order to prove that while the figures of the statistician thus tell a pleasant tale only when he is justified in prophesying smooth things, we have the other side of the shield held up to view, and it is shown that as the mortality from small-pox decreased, the deaths from scarlet fever, clearly traceable to the increasing density of the population, So again, the evidence is complete as to the indirect causes which contribute to a large increase in the rate of mortality, among which must be reckoned the spread of civilization. A

rose.

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