DISCOURSES on ASTRONOMY.

Waikato Times, Volume XX, Issue 1683, 19 April 1883, Page 3

DISCOURSES on ASTRONOMY.

On- February 20th, Dr. R. S. Ball, F.R.S., Andrews' Professor of Astronomy in the University of Dublin, and Royal Astronomer of lieland, delivered at the Royal Institution the first of a course of four consecutive lectures on "The Supreme Discoveries of Astronomy," illustrated by the oxy-calcium light. The bpecial topic for the afternoon was the scale on which the universe is built. The lecturer began by remarking that it is the laws of pure mathematics which present to us tiuths of the highest generality and principles which must hold good thioughout all space and all time. The supieme discoveries of astronomy were those which in this respect most closely approximate to the truths of mathematics. Chained as we were to the surface of the earth and dazzled by the proximity of the &un, it needed a special intellectual effort to view the solar system in its true perspective. The first step was to apply as far as possible the ptinciples ot rigid measurement. We must attempt a survey of the contents of the visible universe. However imperfect that survey, it would yet yield us information enough to enable us to assign to the solar system its true rank among the heavenly bodies. The measurements of that survey depended upon a sure baseline, and the most convenient base was the true distance from the earth to the sun. Various methods have been employed in the determination of this distance ; the best known was that tound by means of the transit of Venus. So much lias been said and written about the transit of Venus that a comparatively brief sketch would suffice for his present purpose. A conjunction of Venus and the earth took place every 19 months. Owing, however, to the inclination of the path of Venus to the eliptic, it but rarely happened that Venus was actually seen in front of the sun. Such an occurrence, however, took place on December 6th last, but no other would happen until the year 2004. By observing the passage of Venus across the sun from pioperly chosen spots a difference in the time of her entering and leaving the solar disk was perceived. From the exact measurement of these differences of time the distance of the sun could be ascertained. The practical application, however, of this method was beset with difficulties. The atmosphere surrounding Venus and the effects of irradiation made it difficult to catch the precise moment when geometrical contact takes place. There were, however, other methods not so celebrated as the transit of Venus, which might be expected to yield results of a satisfactory nature. He would simply describe the principles of one of these alternative methods, which, taking everything into account, seemed to himself to be certainly free from some of the chief objections to which the other was open. The method to which he referred was based upon the observation of the minor planets, those small bodies which revolve between the orbits of Mars and Jupiter. Last year Mr Gill, the astronomer at the Cape of Good Hope, invited the co-operation of astronomers in the northern hemisphere in an attempt to measure the distance of the suit by watching the minor planets Victoria and Sappho. It was by methods of this kind in which the small point presented by a minor planet could be measured in comparison with an equnlly.small fixed star, that the distance of the sun could be obtained without our needing to await the transit of Venus. The distance of the sun once known became the measuring rod by which to reckon the distances of the stars. The star of 61 Cygni still.remained the nearest of all the known stars in the northern hemisphere. The accordance of the measurements made by Jfrofeisor Awph Hall with

those obtained elsewhere by different methods had reduced the limits of uncertainty within a very narrow compass. It was further pointed out that in the same constellation Cygnus j there is another double star of the same j general type as 61 Cygni, which also j seemed to be within a strictly measurable distance. The direct measurements of star distances were, however, # few and scanty. In most cases the distances of the stars were hopelessly beyond our ken, and to estimate these distances we could only fall back on Mr Herschel's reasoning. If Vega, for instance, were shitted ten times as far as it is it would still be | visible to the naked eye. if 100 times it would still be visible in a small telescope, if 1000 times it would yet be seen in a great telescope. The inference was that some of the minute stars revealed by our great telescopes only must be 1000 times as far off as Veea. In the case of clusters and other still more distant objects we could not form even a reasonable conjecture as to their remoteness or their proportions.

If a cheerful heart is a continual feast there must be a large nuirber of people who do not get a square meal once a year. It is rumoured that the Duke of Edinburgh has accepted the offer of the German Government of a million sterling to forego all his rights and claims in connection with the Grand Duchy. A painful elopement has occurred near Burnley, the absconding women being the mother of nine children. Her husband, a miner, has been working at Durham for three years, during which time he accumulated £200, and on coming home at Christinas he stitched the money in a bed-tick, after which he left with his two eldest sons for Durham. Recently a widower, a bricklayer, became the wife's lodger, and the pair disappeared, taking with them the whole of the hardearned savings of the absent husband. Ax infirmary and dispensary at Rochdale, the gift of a resident, Mr Thomas Watson, has been opened by Mr Blight, M.P. The right lion, gentleman spoke of the need of such institutions in a manufacturing town like Rochdale, and dwelt on the necessity of the townspeople subscribing liberally to keep the hospital in a state of efficiency. In the course of his remarks he alluded to the changes in men's lives. He recollected his father telling him, how when he first came to Rochdale he at first thought he should mairyas soon as he earned a guinea a week. Mr Watson had once been a workman earning less than 30s a week. In 1869, Mr Archibald Winterbottom, merchant, of Manchester and Bradford, failed in the sum of -£46,000 and paid his creditors a composition of 10s in the pound. He has since succeeded in realising a fortune, and on the 23rd October last created some sensation in commercial circles at Bradford by suddenly appearing on 'Change and discharging iv full the amount of his indebtedness by the distribution of cheques to 11 his Bradford creditors to the amount of £20,000. This gratifying illustration of commercial integrity has now been duly acknowledged by the Bradford creditors entertaining Mr Winterbottom at dinner at the Victoria Hotol in that town and presenting to him a handsome service of silver plate. The experiments with torpedo boats at the recent naval review at Spezi, in the presence of the king of Italy, appear from the report of Mr Beauclerk, secretary to the British Embassy in Rome, to be regarded by the Italian naval authorities as establishing facts of great importance. The monster ironclads Dandolo and Duilin, having steamed up the gulf to fire blank cartridge, became, we learn, in a very short time enveloped in a dense cloud of smoke so that two torpedo boats able to approach within 200 metres of them (that is to say, within the distance necessary for launching the torpedo) without being signalled, though those experiments were made in broad daylight. The experiments made by night at Spezia gave even more striking results. All the torpedo boats employed succeeded in attaining their object, and one of them came within ten metres of the Venezia. It is (adds Mr Beauclerk) at once suggested by the above incident that had Arabi Pasha possessed some torpedoboata on the occasion of the late bombardment of Alexandria, the position of the English fleet might have been very critical. In speaking of the Jersey Lily's stay in NewYork,thefollowinsrgood story is told, which is rich :—lt: — It seems that two very pretty young girls were strolling 1 up Fifth Avenue a few days since when they noticed Mrs. Langtry walking in front of them with Mrs. Labouchere. They hurried up so as to pet a good look at her, and as they passed her Mr*. Langtry said to Mrs. liabouohere: " Do you call these girls pretty ? " "No " replied Mrs. Labouchere, in her loudest voice, " I do not, and I haven'f seen a pretty girl since I came to America." "Isn't it odd?" said Mrs. Langtry, " there doesn't seem to bo any pretty girls here at nil. " This was said in very loud tones, evidently intended for the passers-by to hear. American wit was her match, though. " Isn't that Mrs. Langtry ? " paid one of these girls to the other, looking round at her. "Oh dear no, that is not Mrs.. Langtry," wra the reply, given in a good clear voice : "Mrs. Langtry is pretty, and this woman U not, and Mrs. Langtry is well bred, and thin woinnn certainly is not. " To say that Mrs Labouchere's pale eyes flashed fire would be doing injustice to the daggers which leaped from out of them. It was this that led to the quarrel which caused Mr Labouchere's prompt return to England.