A little ramble through 19th century astronomy - Repairs to the Madras Observatory in 1890

 Madras Weekly Mail Wednesday 5^th February 1890 

 

THE MADRAS OBSERVATORY

 

Mr. N. Pogson, C.L.E , Government Astronomer, in submitting an estimate of Rs. 2,772 for making certain repairs, reports an follows:

 

Herewith, I have the honor to submit, in duplicate, an estimate for necessary repairs of the Government Observatory, amounting to Rs 2,772, together with an accompanying report by H. Irwin, Esq., C.L.E the Consulting Architect to Government. The repairs have been much needed for some years past, but were deferred, as the transit circle could not then be spared without serious inconvenience. This fine instrument, which cost I, believe about £1,200, was under the very beams, the collapse of which was most imminent; so after Mr. Irwin’s  warning I lost no time in dismounting and removing the transit circle on a strong temporary wooden roller stand to a more secure part of the observatory, pending the repairs of the transit circle room. The telescope cones, bearing the eyepiece and objective, the counterpoises, damps, microscopes, &c., were all taken off on November 16th, assisted by workmen from Messrs. P. Orr and Sons; in consequence of the risk in case of heavy rain, the remainder of the instrument, weighing about 400 lb, was carefully removed bodily on Sunday, November 17th, and the building placed at the Consulting Architect's disposal for whatever emergent precautions in the way of propping and otherwise securing the roof he might consider necessary. During the repairs of the transit room the Madras mean time has to be determined by means of a small transit instrument by Dollond, formerly in use between 1858 and 1862, but with which the time in less certain within half a second than it is within half-a-tenth of a second with the transit circle. The early completion of the repairs is most desirable and advantage will be taken meanwhile for thorough cleaning up of the large instrument on the spot under my own immediate superintendence with such help as I can obtain from Messrs. P. Orr & Sons. The estimate has been sanctioned by government.

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A little ramble through 19th century astronomy - comet Coggia 1874

 Academy Newspaper Saturday July 11^th 1874

 

The comet discovered by Coggia on April 13 1874 has during the last fortnight rapidly increased in brightness and is now a conspicuous object in the northern sky. It will continue to get brighter, but unfortunately its motion is directly away from the pole, and as it is now beginning to move south rapidly, it will soon get below the northern horizon, so that probably it will not be visible to the naked eye, in the northern hemisphere at least, after July 15, when it will be nearly as bright as a first magnitude star, though very low down.

 It is possible, however, that its tail may be seen after the head has set, as was the case with the famous comet of 1843, Mr. Hind, who has devoted much attention to the present comet, considers that it may be seen in full daylight south of the sun with a powerful telescope about July 22, when it makes its nearest approach to the earth. The circumstance that the apparent path of this comet passes nearly through the sun’s place, coupled with Its very slow motion at first, has made it very difficult to compute its orbit; but theory and observation now agree well, and if observatories in the Southern hemisphere watch it carefully, no less than 200° of its orbit will be fixed, and we can then determine whether it is likely ever to visit us again.

The striking feature of this comet in the telescope is its remarkably bright planetary nucleus, from each side of which a fan of light shoots out transverse to the tail. The spectrum of this nucleus, as found by M. Royet (since confirmed by Mr. Lockyer and at Greenwich), is continuous, indicating a glowing solid or liquid, and therefore supporting the theory that it is a meteor stream. The coma and tail which form the usual parabolic envelope give the characteristic spectrum of carbon consisting of three bright nebulous bands, but what is the form under which the carbon exists remains an interesting question which it is to be hoped that Mr. Huggins will resolve. The tail shows strong radial polarisation.

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Cooke telescope tales - Exhibition of the Phonograph in York

 At this time of year Christmas music is being played everywhere, but a long time ago before music was available online or on a CD there was the phonograph or record player as it would become known was invented in 1877 by Thomas Edison.

On the 17^th December 1878 the first phonograph to be seen in York was exhibited at the Kenrick Rooms, Spen Lane in York by Messrs T Cooke and Sons. Permission had been obtained by Cooke and Sons from the London Stereoscopic Company who had purchased the British patent from Mr Thomas Edison the inventor. 

The phonograph was explained by Mr Cox-Walker of Cooke and Sons. Briefly the phonograph consists of a brass cylinder, around which turns a spiral grove. The operator speaks into a mouthpiece upon a thin diaphragm, exactly like a telephone, to which a metal point is attached. The cylinder is covered with tin foil, and the point being in connection, and the handle turned while the operator is speaking, the point runs in the groove and makes several indentations in the tin foil corresponding to the vibrations of the diaphragm caused by the voice. On turning the reverse way the sounds are reproduced, the indentations in the tin foil, acting upon the metal point, causing the diaphragm to vibrate and communicate its motion to the air. 

The singing is very distinct, but the reproduced words of a speaker are somewhat thick, though the result is marvellous in the extreme. Two instruments were exhibited, one working by clock work and the other by hand. By the former the tone is reproduced more correctly, owing to the greater regularity in the turning of the instrument.   

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A little ramble through 19th century astronomy - S Delphinus in 1865

 

Astronomical Register January 1866 

Mr Baxendell read a communication on the variable star S Delphinus, at the meeting of the Literary and Philosophical Society of Manchester. On the 9^th November 1865. A maximum brightness occurred on the 9^th August 1865, magnitude 8.9, the mean period being 332 days, and the minimum equalling the magnitude 13.5. 

Mr Baxendell’s observations were confirmed in a great measure by Mr G Knott of Cuckfield. The colour iof the star is reddish, and is more intense at the minimum.

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The Astronomy Show on Drystone Radio

 Join me, Martin Lunn MBE every Monday evening from 7.00 pm-9.00 pm on the award-winning Astronomy Show on Drystone Radio, probably the only regular astronomy show on any radio station in the country. 

I will take my weekly look at the night sky and look at all the latest news in astronomy. There will be the astronomical anniversaries this week plus the latest news from the astronomical societies in the north of England.

The Astronomy Show every Monday evening only on Drystone Radio live online at www.drystoneradio.com DAB radio in Bradford and East Lancashire, or 102 and 103.5 FM and can also be heard later on the Drystone Radio Podcast.

Cooke Telescope Tales - Accident at the Cooke factory

On December 28^th 1866 the son of Mr W Tindall printer of Fulford Road, York an apprentice with Messrs Cooke and Sons Opticians, of this city, lost his right thumb which was taken completely off by a portion of the machinery on the works, whilst he was engaged in his ordinary occupation. 

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A little ramble through 19th century astronomy - spectra of comets

 

Nature January 8^th 1874

On the spectra of Comets

Here is a summary of comet spectra by H Vogel published in Poggendorffs Annalen

I will now give a summary of all the observations known to me of cometary spectra. 

1.      The first comet examined by spectrum analysis is the Comet I. 1864. Donati found its spectrum to consist of three bright bands, which (if one may judge from the figure in Astr Nachr No. 1488) do not  coincide with those of the hydrocarbon spectrum.

2.      Huggins and Secchi observed Temple’s Comet I. 1866, and got from it a weak continuous spectrum, in which Secchi saw three bright lines, Huggins only one. The line seen by both was the brightest, and situated in the middle between b and F of the solar spectrum; accordingly no coincidence with the hydrocarbon spectrum.

3.      In the spectrum of Comet II. 867, the continuous spectrum was relatively so strong that Huggins found it difficult to detect bright lines. “Once of twice”, he says “I suspected the presence of two or three bright lines, but of this observation I was not certain. The prismatic observation of this faint object, though imperfect, appears to show that this small comet is probably similar in physical structure to comet I.1866” In this case again probably no hydrocarbon.

4.      Brorsen’s Comet I. 1868 was observed by Huggins and Secchi. Both observed three zones of light; The middle one being the brightest, and lying in the green; while its brightest part was somewhat less refrangible than the brightest line of the air spectrum. From this observation, and the determination of the position of the other two faint bands, it appears that the comet spectrum was neither similar to that of nitrogen, nor to the hydrocarbon spectrum.

5.      Winnecke’s Comet II.1868, was also observed by Huggins and Secchi. The measurements and direct comparisons of Huggins gave an agreement of the cometary spectrum with that of carbon in olefiant gas. From Secchi’s measurements it appears that the sharply defined side of the middle band (towards the red end), nearly coincided with the line group b of the solar spectrum; at which part also the beginning of the middle band of the spectrum of hydrocarbon id situated.

6.      Comet I. 1870 was observed by Wolf and Rayet; the spectrum consisted of three bright bands, whose position, however, was not accurately determined.

7.      Comet I. 1870 was observed by Huggins and myself. Huggins found three bands, I only two. The measurements of the bands observed in common agree well; the spectrum appears to be identical with that of Brosen’s Comet.

8.      Comet III. 1871 (Encke) was observed by Huggins three days, by Young four and by myself six; it showed, as usual a spectrum of three bands. Huggins thought this agreed with the hydrocarbon spectrum ; while young and I observed no such coincidence.

9.      Comet IV. 1871 (Tuttle), examined only by me, gave a spectrum of three bands. Accurate measurements of their positions showed no coincidence with the hydrocarbon spectrum.

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