LETTERS TO THE EDITOR

Dominion, Volume 6, Issue 1750, 15 May 1913, Page 3

LETTERS TO THE EDITOR

THE PROPOSED SOLAR OBSER- I VATORY. KKi'i.it:s to mi;. nii,i;i;ii)(it: r.\Ki;. Sir,---In y.itn' „|' >| l( v iii yen pub-! b-li a long h'llor j'roin IJr, Coleridge t'arr "" subjcct ii|' Hi,. 11 i'ijpi>- ;■(! Solar I hy-iis Ob-crvatory. I do not wish to take up s;v inut'll ol' your space as ill'. I'arr ha- iloue, lull, in justice to the peopled New /oaland, lo Mi-s I'roctor, to •>lr. (nwlliron, anil to those who have takiMi 11 special intere-l in this matter, think some reply >hould |j« made to -IJr. larr's statements. Dr. I'arr "considers, it to be the duty ot scientific men lo stale fearlessly ,and without hesitation their opinion on scientific. matters." Hut, .surely, 110 scientific man of tho present day*" would try to simulate Francis Jlacon and attempt "io tako all knowledge for his province." However eminent a man may lie in 0110 branch of science at the present day that does not necessarily qualify liiin for giving an opinion on another branch of science, and unless he is so qualified such a proceeding would Ire both unscientific and indiscreet. Dr. Parr's letter consists largely in the elaboration of an idea which is fundamentally wrung. He says, in ell'ect, tluit a Solar Physics Observatory in New Zealand would be practically useless 011 account of its high latitude. He assumes that the sun should be at the zenith for the best, work lo be done. If he will read the reports of the recent. British Sohir Physics Commission, of the South Kensington Solar Physics Observatory (now removed to Cambridge), of the Mount \Yilson Observatory he will find that all the leading observers agree jn stating, that tile best results are obtained during tho first hour or two after dawn, when the sun is only (en or fifteen degrees abovo tho horizon. This being tho case, a certain degree of latitude beyond the tropics would be an advantage because the sun would rise more obliquely and therefore more slowly to the height of ten or fifteen degrees above which it charges the air with undesirable water vapour.

He will also find it staled that even at.tlie high latitude of London (aldeg. N.) results are occasionally obtained which aro equal to those obtainable at any observatory in the world. So it is not tho altitude of the sun (for it is useless at noonday) which affects the problem, but the clearness of the air and its freedom from moisture just after dawn. The clearness of the New Zealand atmosphere is well known, the freedom from moisture just after dawn must depend on local climatic conditions and 011 the contour of the surrounding country. Tho longitude of New Zealand is admitted to be pre-eminently suitable. AVhether a suitablo site can or cannot be found in tho neighbourhood of Nelson can only bo decided by those who aro really expert in the subject of Solar Physics, and it is to be hoped that in the interests of Mr. Cawthron and in the interests of the Dominion an expert may now be import«l from one of tho wellestablished Solar Observatories. He could decide the question of the availability of a site near Nelson and take charge of the observatory, if established, so that work could be commenced on the most economical, and proper lines. AVitli regard to the Geographical Observatory which Dr. Furr would like to sec established and tn which, apparently, he would lie glatl to divert Mr. Cawthron's thousands, I may say it is quite open Caiul always has been) to Dr. Farr lo canvass the country for funds in aid of that object. 1 am in complete agreement,, with Dr. Farr in my desire and hope to see a first-class Stellar Observatory established in the dry, clear air of Central Olago, but. fuller, acquaintance with the subject, will probably convince Jiim that the Solar Observatory is quite as •urgent a necessity as the Siellar one. In conclusion, I would like to repeal' that, if js not proposed "to establish a Solar Physics Observatory in New Zealand regardless of whether it is of much real to the world or not." The be ; lief is widely held that such an observatory would be of great utility and importance. But it is proposed to take the opinion of experts ill the matter and I hope the mailer will 1:0 decided regardless of (lie opinion of those who are not qualified to give an opinion on the matlei'.—l am, etc., C. MONRO HECTOR, M.D.. B.Sc.

Sir,—Before anyone presumes Jo adopt the dogmatic tone which characterises Jfr. Coleridge Farr's letter of Hay 10, be should certainly be a thorough master of Hie subject he is writing about. But what aro we to think of one who assumes the, airs of a professor of astronomy and yet speaks of Mount AVilson as being in Arizona, and repeatedly transforms Kodaikanal into Kodai Canal ? No one whose knowledge of solar physics was not extremely superficial could possibly make such amazing blunders. Mere straws show which way the wind blows, and mistakes' of this kind make one inclined to attach very little importance to Mr. Farr's opinions about solar physics. Mr. Farr's argument really amounts to this: If you cannot locate your solar ol>servatory in the tropics, it is a waste of money to put one up at all. I wonder whether Mr. Farr is aware of tlio excellent work in solar physics _ which has been accomplished by Sir Norman Lockyer at South Kensington in England? .Does he know that it has recently been proposed to carry on tho samo lino of research either at Cambridge or at Fosterdown? If Mr. Farr is right, the authorities in England are a pack of fools to waste their money thus, for it may bo confidently asserted that no site could be found in tho British l-les which offers such advantages for solar research as does Nelson in New Zealand. Mr. Farr is evidently under the impression that, solar observations are made when the sun is upon or near the meridian. Both at Mount Wilson anil at Kodaikanal all the best work is done during the early morning hours when the sun is at no great height above the horizon. For this anil oilier reasons Ihe disadvantage of having the observatory outside the tropics is by 110 means so creat as Mr. Farr would have 11s believe. Moreover, it is obvious- enough that if we aro to wait for 11 Solar Observatory in this part of the world until one is built in Fiji or Queensland, we shall have to wait for a great many years. In the meantime there is 110 doubt that ft Solar Observatory at Nelson could produce results of tho greatest value. Many other statements in Mr. Farr]s letter are open to criticism, such as his remarks about the climate of Nelson's mountains, about which I can claim to know something. But I will only say in conclusion that Mr. Farr can scarcely bo complimented upon his methods for encouraging wealthy men to assist scientific research. Ho practically tolls Mr. Cawthron that he is making a foolish blunder and is throwing away his money. Other rich men may well deem it wiso to avoid making such blunders by tho simple expedient of keeping their money in their own pockets. Fortunately Mr. Cawthron has received so many highlynppreciativo letters from men who really do know something about solar physics and to whom Mount AVilson and Kodaikanal are therefore as familiar as honsciiulil words, that he is not- likely to be perturbed by Air. Farr's arrogant criticism which is no less baseless than it is ungracious—l am, etc.. F. G. GIBBS. Nelson.