HOW TO WATCH THE TRANSIT OF VENUS.

Waikato Times, Volume VII, Issue 381, 22 October 1874, Page 2

HOW TO WATCH THE TRANSIT OF VENUS.

In answer to queries of one or two correspondents, who are desirous of learning a simple method of watching the transit of Venus aci'oss the sun's disc. Mr Ellery, the Government astronomer, has kindly supplied the following notes to the dus/ra/asian, which will be useful for the guidance of amateur observers : — " Observations of the transit of Venus across . the sun's disc will be principally confined to the determination of the exact time at which the planet's disc enters upon that of the sun ; and those particular instants when the outer edge of the planet is in precise coincidence with, the sun's edge, called internal contacts, will be taken. These contacts occur when Venus first shows, as a full round disc on entering on the sun's disc, and again while she still shows a round disc just before egress. Such observations require the use of good telescopes well mounted, witk apertures of not less than 3in. or 2|in. ; they also require the use of a good clock or chronometer, and the exact mean time or sidereal time. " For simply viewing the phenomenon very simple apparatus will be sufficient. To good eyes protected by deep colored or smoked glass, Venus will be visible after she is well on the sun's disc. Any ordinary telescopes, and even binocular, opera, or field-*-' glasses, will give a better view ; but whatever telescope is used, great care is necessary to protect the eye from the intense gjave and heat concentrated at the eye apei-ture, and if proper sunshades are not^ provided they must be impi*ovised before attempting to look at the sun, for many have lost or injured their eyesight by not attending to this most necessary precaution. Deeply' colored glass, especially a piece of deep red, and a piece of deep green or blue together, would be found very safe and pleasant ; a piece of blue and green, or deep neutral tint, will also do nicely. If none of these can be obtained, th« old-fashioned smokedglass will form an excellent substitute. The proper method of making this is — Obtain two strips of thin clear glass, say 3in. long by lin. broad (the glass sold for microscopic slides is the best) ; around the margin of one of the surfaces paste a strip of thin writing paper about the eighth of an inch broad,, and smoke this surface by holding the slip. over a candle with, a long- wick or a small kerosene flame (without chimney), taking care to warm the glass gradually at first, or it will crack. The proper density of the blackening can be got after a few trials. After the right kind of smoked surface has been obtained, the second glass can be fastened over it ; the strips of paper will keep it from coming into contact ;. by pasting a strip of thin paper over the edges so as to hold the two glasses together a dark shade for observing the sun is formed, which will last any length of time."

An interesting little establishment has just been broken up at Trcbizond under circumstances which, have created, if not a " scandal," at least a sensation in that place. It appears that for some time past Trebizond has been kept in a state of uneasiness owing to the proceedings of this household, wliich consisted of a father, six sons, and one daughter. | Delightful as was the charm which reigned over their domestic circle, it did not extend beyomd the hearth, for, unfortunately, the family weakness was murder. In a biief space of time the eight persons composing the family managed to get through, according to the Trebizond correspondent of the Levant Herald, no fewer than 235 murders. Out of this number the gentlemen of the family were each responsible for thirty murders, while the young lady only committed twenty-five, though, for the premature interterence of the authorities, it is considered probable that she would have completed an equal number. The predecessors of the present Governor most ungallantly caused her to be arrested, together with her amiable parent and four of her brothers. It is not stated what became of the remaining brothers, but the poor old gentleman was hanged about three months ago, and two of his sons met with a similar melancholy accident on the 25th of 1 ist month. The other two and the young lady are still languishing in captivity, and much anxiety is felt on their behalf, for unless the local judges take a lenient view of their offences on account of their youth they have but a poor chance of resuming their position in society. Altogether it is a sad story, and it is not surprising that these young people and their misfortunes have of late been the talk of Trebizond. I A telegraphic message was recently despatched from Adelaide to Bombay, the delivery to the person to whem it war, sent and the receipt of an answer in Adelaide occupied leta than ejjght minutes.