owned, fat was true aneuch, that the fush had fairly bestit her. Weel, amo' the veesitors at the Castle was the Dowager Leddy Breadanham; an' it seemed that whan Leddy Carline was through wi' her narrateeve, the dowager be tae gie a kin' o' a scornfu' sniff an’ cock her neb i' the air; an' she said, wha but she, that she didna hae muckle opingin o' Leddy Carline as a saumon fisher, an' that she hersel' didna believe there was a fush in the run o' Spey that she cudna get the maistery ower. That was a gey big word, min' ye; it's langidge I wadna venture for tae make use o' mysel', forbye a south-countra dowager.

'Weel, I didna say muckle; but, my faith, like the sailor's paurot, I thoucht a deevil o' a lot. The honour o' Spey was in my hauns, an' it behuvit me for tae hummle the pride o' her dowager leddyship. The morn's mornin' cam, an' by that time I had decided on my plan. o' operautions. By guid luck I fand the dowager takin' her stroll afore brakfast i' the floor-gairden. I ups till her, maks my boo, an’ says I, unco' canny an' respectfu', "My leddy, ye'll likely be for the watter the day?" She said she was, so says I, "Weel, my leddy, I'll be prood for tae gae wi' ye mysel', an' I'll no fail tae reserve for ye as guid water as there is in the run o' Spey!" She was quite agreeable, an' so we sattlit it.

The duke himsel' was oot on the lawn whan I was despatchin' the ither fushin' folk, ilk ane wi' his or her fisherman kerryin' the rod. "Geordie," said his Grace, "with whom will you be going yourself?" "Wi' the Dowager Leddy Breadanham, yer Grace!" says I. "And where do you think of taking her ladyship, Geordie?" speers he. N'odd, yer Grace," says I, "I am sattlin in my min' for tae tak the leddy tae the 'Brig o' Fochabers' pool;" an' wi' that I gied a kin' o' a respectfu' half-wink. The duke was no' the kin' o' man for tae wink back, for though he's aye grawcious, he's aye dignifeed; but there was a bit flichter o' humour roun' his mou' whan he said, says he, "I think that will do very well, Geordie!"

'Praesently me an' her leddyship startit for the "Brig o' Fochabers" pool. She cud be vera affauble whan she likit, I'll say that muckle for the dowager; an' me an' her newsed quite couthie-like as we traivellt. I saftened tae her some, I frankly own; but than my hert hardent again whan I thoucht o' the duty I owed tae Spey an' tae Leddy Carline. Of coorse there was a chance that my scheme wad miscairry; but there's no a man on Spey frae Tulchan tae the Tug Net that kens the natur' o' saumon better nor mysel. They're like sheep-fat ane daes, the tithers will dae; an' gin the dowager hookit a fush, I hadna muckle doobt fat that fush wad dae. The dowager didna keep me vera lang in suspense. I had only chyngt her fly ance, an' she had maist fushed doon the pool a secont time, whan in the ripple o' watter at the head o' the draw abune the rapid a fush took her "Riach" wi' a greedy sook, an' the line was rinnin' oot as gin

there had been a racehorse at the far end o't, the saumon careerin up the pool like a flash in the clear watter. The dowager was as fu' o' life as was the fush. Odd, but she kent brawly hoo tae deal wi' her saumon that I will say for her! There was nae need for me tae bide closs by the side o' a leddy that had boastit there was na a fush in Spey she cudna maister, sae I clamb up the bank, sat doun on ma doup on a bit hillock, an' took the leeberty o' lichtin' ma pipe. Losh! but that dowager spanged up an' doun the waterside among the stanes aifter that game an' lively fush; an' troth, but she was as souple wi' her airms as wi' her legs; for, rinnin' an' loupin' an spangin' as she was, she aye managed for tae keep her line ticht. It was a dooms het day, an' there wasna a ruffle o' breeze; sae nae doobt the fush was takin' as muckle oot o' her as she was takin' oot o' the fush. In aboot ten meenits there happent juist fat I had expect it. The fush made a sidelins shoot, an' dairted intil the vera crevice occupeed by Leddy Carline's fush the day afore. "Noo for the fun!" thinks I, as I sat still an' smokit calmly. She was certently a perseverin' wummun, that dowager-there was nae device she didna try wi' that saumon tae force him oot o' the cleft. Aifter aboot ten meenits mair o' this wark, she shot at me ower her shouther the obsairve, "Isn't it an obstinate wretch?" "Aye," says I pawkily, "he's gey dour; but he's only a Spey fush, an' of coorse ye'll maister him afore ye've dune wi’ him!" I'm thinkin' she unnerstude the insinivation, for she uttert deil anither word, but yokit tee again fell spitefu' tae rug an' yark at the sulkin' fush. At last, tae mak a lang story short, she was fairly dune. “Geordie,” says she waikly, "the beast has quite worn me out! I'm fit to melt-there is no strength left in me; here, come and take the rod!" Weel, I deleeberately raise, poocht ma pipe, an' gaed doun aside her. "My leddy," says I, quite solemn, an' luikin' her straucht i' the face-haudin' her wi' my ee, like-" I hae been tellt fat yer leddyship said yestreen, that there wasna a saumon in Spey ye cudna maister. Noo, I speer this at yer leddyship-respectfu' but direck; div ye admit yersel clean bestit-fairly lickit wi' that fush, Spey fush though it be? Answer me that, my leddy!" "I do own myself beaten," says she," and I retract my words." Say nae mair, yer leddyship!" says I-for I'm no a cruel man-" say nae mair, but. maybe ye'll hae the justice for tae say a word tae the same effeck in the Castle whaur ye spak yestreen ?" "I promise you I will," said the dowager-"here, take the rod!" Weel, it was no sae muckle a fush as was Leddy Carline's. I had it oot in a few meenits, an' by that time the dowager was sae far revived that she was able to bring it in aboot tae the gaff; an' sae, in the hinner end, she in a sense maistert the fush aifter aa'. But I'm thinkin' she will be gey cautious in the futur' aboot belittlin' the smeddum o' Spey saumon !'

66

VOL. XXXVIII-No, 221

ARCHIBALD FORBES.

G

RECENT SCIENCE

I

50000

No substance in nature seemed to be better known to chemists than atmospheric air. The composition of air taken from the most different localities and altitudes had so often been analysed by the best chemists and physicists that up to the last few years it seemed almost inadmissible that any gas existing in the atmosphere should have escaped detection. However, modern chemistry disposes of such perfect methods of analysis, and our modern laboratories are supplied with such wonderfully precise instruments-it is sufficient to say that in a modern weighing the incertitude is inferior to th part of one ounce that when the study of air and other gases was again taken in hand with the aid of the new instruments and methods, a vague suspicion began to grow up. After all,' it was said in scientific circles, 'atmospheric air is not so very well known,' and it possibly may contain small quantities of some unknown gases mixed with its principal components-nitrogen and oxygen, carbonic acid, and vapour of water. These suspicions are now fully confirmed. When the researches of Lord Rayleigh and Professor Ramsay were published in full, it became evident that atmospheric air contains over one-half per cent. of some gas (or maybe gases) formerly unknown, and that this gas-named Argon by its discoverers-is possessed of chemical properties which offer many a puzzle to the chemist. The distrust which the announcement of the discovery was met with in August last has been dissipated since, and the question, What argon is? stands now foremost.

Is it an element which, like hydrogen or oxygen, cannot be decomposed into still simpler bodies-a chemical individuality,' as Mendeléeff says, which maintains its individual character even when it combines with other individualities? Or is argon a mixture of

'Mendeléeff, in his Principles of Chemistry (English edition, vol. i. p. 226, note 12), already expressed the opinion that, under the electrical discharge, the nitrogen of the air may be partially dissociated, giving origin to monatomic molecules (N). Helmholtz, having received the news of the discovery of a new constituent of the atmosphere, said that he always thought that there was something more in the atmosphere' (Lord Rayleigh's lecture on Argon at the Royal Institution).

several new elements? Or is it a compound of well-known elements which were never met before in that special combination? These questions press themselves upon every one's mind. However, up to the present date they have not been answered, and most probably the answer will not be given for some time to come, not only because the discovery of argon was immediately followed by the discovery of several other gases, but also because argon is so peculiar in its behaviour as to raise a host of questions of paramount importance for chemistry. The general reader, accustomed to get from science ready results, may therefore feel disappointed when, after having perused the following pages, he only finds a number of new unsolved problems cast upon science. But, to follow step by step the inquiry which is now going on, to share the hopes and the doubts of the explorers, and thus to be initiated into the mysteries of scientific research itself, and into the methods of discovery of scientific laws, is perhaps even more interesting, and certainly much more suggestive, than to learn some time later the bare results.

For the last seven years Lord Rayleigh has been engaged in remeasuring the densities of the commonest gases, with all the precision obtainable from modern appliances, and his work was soon recognised to be a standard work. However, even in the earlier stages of his researches, while he dealt with oxygen and air, there appeared certain discrepancies between his otherwise most accurate results, which, precisely because the measurements were so perfect, could not well be explained by unavoidable errors, and created a certain uneasiness as to the permanence of the constitution of air. But when he came later on to deal with nitrogen, things took a more serious aspect. Nitrogen is an element; and, whether it be obtained from the air or from one of the nitrogen compounds, such as ammonia, it must always be the same gas, endowed with the same physical and chemical properties. And yet this was not the case. Nitrogen obtained from the atmosphere by any one of the usual methods was regularly by about one-half per cent. heavier than nitrogen obtained in the chemical way from some compound. In each of the two sets of determinations the measurements beautifully agreed together; but the two sets totally disagreed, although all possible precautions had evidently been taken to prevent contamination by other gases, and a strong control was exercised to detect contamination if it had taken place. The disaccord had to be explained.2

The nearest explanation was, of course, to find fault with the chemically prepared nitrogen; notwithstanding all precautions it might still contain some lighter gas-hydrogen for instance; but test experiments were installed and compelled the rejection of this explanation, so that there remained but one other alternative-namely,

2 The average weight of one litre of nitrogen was 1.2572 grammes when it was derived from the atmosphere, and 1.2505 grammes for chemically obtained nitrogen.

that the atmospheric nitrogen, supposed to be the purest of the two, was not pure at all; that it contained some heavier gas which enters into the composition of the atmosphere to no small amount, but in some way or another had hitherto escaped notice. Lord Rayleigh naturally hesitated to draw a conclusion so much opposed to all current opinion, and in his perplexity he applied through the medium of Nature to chemists, asking them to aid him with their suggestions.3 The suggestions came, and in a great number; but none of them explained the difficulty. Some time later, Professor Ramsay asked and obtained permission to investigate the matter, and the two explorers, the physicist and the chemist, working first separately, made the necessary arrangements for isolating the new heavier gas by two different methods. They obtained it, nearly pure, and on account of its unwillingness to enter into any chemical combination they proposed for it the name of Argon. The discovery was announced at Oxford, at the last meeting of the British Association.

This announcement, as already mentioned, was met with a great deal of distrust, which only grew stronger as time went on, and nothing was heard during the next five months in support of so important a statement. It was only after all the details of the researches were made public at the end of January last that all doubts as to the real existence of a new constituent of the atmosphere were removed, and the whole inquiry was recognised by competent judges as an exemplary chemical research."

The first step to be made in an inquiry of this sort is evidently to obtain the new body in sufficiently large quantities for chemical analyses. This proved, however, to be a hard task. If argon easily combined with other bodies, any amount of it could be obtained, because the nitrogen of air, of which there is an unlimited supply, contains as much as one per cent. of argon. But the new gas refuses to enter into chemical combinations, and it is neces sary to absorb all the oxygen, nitrogen, carbonic acid, and so on, from a given considerable volume of air, and to obtain argon as a residue. Yet nitrogen in its turn is also a very inert body, which it is easy by no means to force into a chemical combination; so that, after oxygen and the rest have been eliminated, there is still the difficulty of removing nitrogen from the mixture. It must, for instance, be passed for hours again and again over some red-hot magnesium or lithium, until, most of it having combined with the

September 29, 1892, vol. xlvi. p. 512. See also his two subsequent communications to the Royal Society.

• Proceedings of the Royal Society, January 31, 1895; Nature, February 7, 1895, vol. li. pp. 347-356.

› Mendeléeff, Proceedings of the Russian Chemical and Physical Society, March 2 (14), 1895; and in Nature, vol. li. p. 543; Berthelot in Comptes Rendus, February 4, 1895, tome cxx. p. 235 sq.

This last, the lithium method, has been experimented upon with success at Nancy, by Guntz (Comptes Rendus, April 8, 1895, vol. cxx. p. 777).