« AnteriorContinuar »
ed like a cloud of more than ordinary merely regarded as brilliant clouds ; magnitude, and probably very gene- but they exhibit, in fact, every variety rally mistaken for such a cloud ; from of form, from that of a slight fleecy apits southern portion, however, it emnit- pearance, only to be distinguished by ted a fine brush of electrical light, the most skilful eye from ordinary which gradually stretched itself east- collections of buoyant vapour, to those Fard, till it nearly reached the hori- beautiful phenomena which, under the zon, and, having continued in this form of the bow, are amongst the situation for a short time, the whole most magnificent appearances which mass slowly disappeared from the face the atmosphere presents. The indiof the sky.
cations of an Aurora, besides, are the
unfailing attendants of such phonoI have been particular in describ- mena ; frequently, when the Aurora ing these appearances for two rea becomes widely diffised, its most visons ; because, in the first place, vid corruscations occupy the situation the phenomena themselves are rather where immediately before the bow of rare occurrence, and are, therefore, had been observed; and every conworthy of being recorded for the pur- sideration serves to shew, that the pose of comparison with future appear- matter which is employed in all these ances of the same kind. The Aurora appearances is the same, and that its itself is well known to be a phenome- more rapid movement in the case of non which only occurs after irregular an Aurora, and the beautiful tints alintervals, sometimes of very consider so by which it is characterized, are able length; and, the splendid meteor either the effect of its moving in a of the bow requires so many favourable freer medium, or of its being developcircumstances for its exhibition, that ed in a less condensed and accumulatwe cannot wonder it should have been ed form. so seldom observed. It seems, indeed, Next to the splendour of the light that some old people in the north of itself, its beautiful regularity when in England recollect to have seen such the form of a bow, will naturally atappearances in their younger days; tract the observation of the curious. but, for many years, the meteor had There cannot, however, be any doubt, not been observed in this country, that the arched appearance which the and when it again presented itself bow assumes is merely an optical, three years ago, even the best inform- though certainly a very pleasing illued seemed to be equally struck with sion,—that it risults entirely from our wonder at the beauty of the phenome- disposition to refer the phenomenon non itself, (for, next to the rainbow, to the arched appearance which the it is certainly, of all meteorological ap- heavenly vault itself assumes ;-—and is pearances, the most magnificent,) and to be explained in the same way in with astonishment at the little ac which Mr Dalton and Mr Cavendish quaintance they had previously had have accounted for the similar form of with it.
the Aurora Borealis. From the deMy chief inducement, however, in monstration of Mr Dalton, it is cerpresenting to your readers the above tain that the Aurora consists of a particulars, was that of directing their great number of straight cylinders attention to the following conclusion, parallel to each other, and to the namely, that though, when the phe- dipping needle at the place where nomenon of the bow is exhibited, it they are seen. The luminous arch, in seems to be distinguished by several the same manner, is merely to be conof its properties from the usual cha- sidered as a great body of electrical racteristics of the matter of an Aurora, matter, existing in a very condensed we are yet able to trace a series of ap- or insulated state, either parallel to pearances which serve most complete- the horizon of the place of observation, ly to connect these phenomena. Mas or developed obliquely from strata of ses of electrical matter developed in air, which are, at the time, in the same the atmosphere are, in fact, of much state of electrical charge. To this more frequent occurrence than inat- obliquity it may perhaps sometimes he tentive spectators are apt to believe. owing that one extremity of the arch These appearances, indeed, 'are often seems to be of greater breadth than altogether unnoticed, from their being the other ; that extremity subtending
the greatest angle at the eye, which is of the bow when in its greatest perdeveloped from a stratum nearer the fection, afford the best of all expediearth.
ents for resolving a problem which is The variation of the magnetic needle of considerable interest, namely, the during such appearances, is one of the average height at which the Aurora most instructive of the circumstances takes place. The method of ascerwhich attend them; and from the fol- taining this, by means of the parallax lowing remarkable coincidences it will of the bow, is well known to philosoappear, that a needle may often indi- phers. Unfortunately, however, no cate, by its variations, an uncommon such correct observations respecting state of atmospherical electricity at a its relative place in the heavens apconsiderable distance from the place pear to have been made during the of the observer,-in the same manner recent appearances, as to afford any as the variations of the barometer are sufficient data for determining this known to indicate storms and hurri- problem. In one instance, indeed, I canes which happen at the distance of know that such a measurement was many miles or leagues. The finest made by a gentleman in the north of needle at present kept in Britain is England, with respect to the bow of probably that of Colonel Beaufoy; up- September 1814 ; but his data were on referring to the published account confessediy inaccurate, and the result of the Colonel's observations for the of his calculations was, that the height period of the bow of September 1814, of the meteor was probably somewhat I find the following note: “ Septem- between six and eight miles. The ber 12, variation remarkable, and the Aurora itself, however, with which morning observation greater than the this phenomenon has a very intimate noon, for which no reason can be as- connection, has been placed (and prosigned. The weather was overcast, bably correctly placed) at all distanand the wind north, blowing at the ces, from sixty to eight hundred and rate of ten miles an hour.” From this one thousand miles ; and, indeed, note it is evident that Colonel Beaufoy when we consider the vast space over had not been aware of the meteorolo- which the meteors I have been degical appearances which were visible scribing were observed, (a space which in the more northern parts of the seems to have embraced some hundred island the evening before, as a know- miles in every direction,) we shall realedge of these appearances would infal- dily allow, that their height must have libly have suggested to him the solu- been immensely greater than, from tion of the difficulty. With respect viewing their appearance, we might to the variations of the needle for Sep- be disposed to believe; and that the tember 26, 1815, on which occasion a accumulation and extent of matter bow was visible at London, though which they contained, must have Colonel Beaufoy does not appear to been proportionally enormous, to prehave known of it, it appears that the sent so remarkable an appearance at variation for noon of that day was 24° so great a distance. 29' 46", which is considerably above A law was long ago stated by Blagthe mean variation for noon of that den, (in the Philosophical Transacmonth. I have had no opportunity of tions, I believe, for 1784,) respecting consulting the variations of the neeille the order in which the electricity of about the time of the appearance of the atmosphere is developed, which the bow of 1816, but I have no doubt assigns the very highest regions of the that considerable irregularities will be air as the sphere appropriated to the found to have happened about that pe- phenomena we have been considerriod. What I have already statd, ing. According to this writer, those however, is sufficient to prove not only rapid and destructive exhibitions of that such variations do occur when the this fluid, which are familiarly known electricity of the atmosphere is re to us under the denomination of lightmarkably agitated, (a fact which has ning, are chiefly confined to the rebeen long ascertained,) but that the gion of the clouds, that is, to the variations of the needle may indicate lower departments of the circumamchanges which are not directly expe- bient fluid. What we commonly derienced at the place of observation. nominate falling stars, are considered
The electrical appearances I have as more appropriate to that higher renow been describing, especially that gion in which the formation of vapour
is seldom perceived, though they may vations on Natural History, by your also sometimes descend into a lower correspondent P. in your last number; sphere ; while the highest regions are and am convinced, that many facts the scene of those appearances which and important remarks may be made the Aurora and its kindred pheno- known in that easy and familiar manmena exhibit. I apprehend that this ner, which would not warrant an elaaccount will be found to be substan- horate or scientific essay on the subtially correct, though of course these ject. For many years as a boy I was different phenomena will often be seen accustomed to travel to my purishto shift their situation according to the school, over a district of wild unculvarying condition of the aërial strata ; tivated country, extending for two or and I have only to add, that I apprehend three miles; and when relieved from a similar law takes place, in the order in the more important duties of the day, whichelectrical phenomena are present- our great amusement in the spring and ed, as we advance from the equatorial summer months, was to ramble over towards the polar regions. It is well that country in search of birds' nests. known, that the electrical appearance Now, Mr Editor, even in those days most frequent at the equator, is that of I was struck with many singular disprodigious storms of thunder and light, coveries (for such I still consider ning; in the serene regions of the them) in the economy of some birds, temperate zone, (though here also that I have not as yet seen explained, storms of lightning occasionally oc or even hinted at, in any scientific cur,) the most common appearance work which I have perused on the which electricity assumes, is that of subject. I shall, therefore, trouble those gliding meteors which serve only you with some of those observations to give additional beauty to the spang- which were made as a boy, and which led glory of a southern sky; and it is I have often had an opportunity of not till we have advanced into those confirming since. more terrific regions which surround To begin, Sir, with the Lapwing the pole, that the Aurora is beheld in or Green-plover, (Tringa Vanellus.) constant activity, and in the utmost This bird, it is well known, genemagnificence it is capable of assuming. rally deposits its eggs in low marshy
Whatever may be the value of these ground. It is not at the trouble of observations, one thing is certain, building a nest, as I have never obthat a series of such appearances as served more than a small round hole I have now been describing, never scratched in some little eminence, fails to indicate a deranged state of with perhaps a few particles of fog or the electricity of the air. We all dried grass between the eggs and the know, accordingly, that the condition moist earth. It lays four eggs; and of the atmosphere, during the three what I have to remark as deserving last years, has been considerably dif- of consideration is, that if the nest is ferent from its usual tenor; and the discovered as soon as the bird has bephenomena I have been discussing gun to lay, and you remove an egg, seem, therefore, worthy of being re so as to allow only one or two to remarked, not only as materials of phi- main in the nest, the bird will conlosophical history, and as appearances tinue to lay for ten or twelve days, in themselves of considerable interest nay, for weeks successively. If, howa and beauty, but as concomitants also ever, you allow the uumber to reach of that very remarkable weather which four, it immediately begins to hatch, has been one of the “ signs” of these and there is no farther deposition of last eventful years, and which seems eggs; but if any of the eggs are then lately to have extended itself over a removed, that is, after the natural very considerable portion of the civie number has once been completed, it lized globe. I am, yours respectful- immediately forsakes the nest and prely,
P. pares a new one. I have myself conEdinburgh, Sept. 3, 1817.
tinued to remove the eggs for ten days
at a time, and always found a fresh OBSERVATIONS ON THE NATURAL
one every morning, and have often tried also to take away one after the
ordinary number four had been comMR EDITOR,
pleted, but always found the nest imI have read with no small degree mediately forsaken. of pleasure the Miscellaneous Obser I have tried the same experiment
HISTORY OF BIRDS.
with the common Lark. If you allow impose upon that wily bird, was cononly one or two eggs to remain in the sidered an acquirement of no trifling nest, the bird will go on to lay for a consequence among the knowing ones time indefinite; but if they reach of those days. If the Magpie disthree the bird will hatch. The com covered the egg, it was indignantly mon number of eggs in a Lark's nest thrown out ; but if the young bird is five; but it will hatch with three. was once hatched, she was even more
I hope some of your readers will attached to the stranger than to her try to explain these facts upon ra own offspring. I have seen several tional principles. They have often game-cocks that first saw the light on puzzled me, more particularly as I have the lofty summit of an old ash tree not seen them noticed in any work on that grew in my father's kail-yard. the n tural history of birds. Here They were certainly much more spiwe have a bird, which, as soon as it rited, and, if I may be allowed the exhas deposited four eggs in its nest, pression, more cruel than when hatchimmediately ceases to produce any ed by their natural mother. Here, more, but if disturbed in its ar- again, Mr Editor, we have a field for rangements will go on to form five, the speculations of the natural histoperhaps ten times that number, and rian.-By the bye, if you disturb a yet cease the moment it has collected Magpie in her operation of building, its usual number for hatching in the she will immediately remove the sticks same spot.
she has collected to another branch of Is it any species of food which the the same tree, but much lower down hen bird uses? or can it be the im- than the one she first occupied. pregnation of the male one, that keeps If you think these facts worth comup this production of eggs, and the municating to your readers, I shall refraining from which causes the sud- have much pleasure in supplying you den cessation,- for sudden it must be with several others not less interesting considered, when it takes place in the in the natural history of animals as course of twenty-four hours ? well as birds. I am your sincere wellBirds that build well regulated wisher,
A. nests, are very assiduous in their la Edinburgh, 4th Sept. 1817. bour until the whole is completed. The male is, in general, the carrier of the materials, and the fomale the architect. Many a long hour have I watched the operations of the Black OF GLASGOW, PAISLEY, GREENOCK, bird and the Mavis, both of which build very elegant nests, and somewhat similar in their construction. MR EDITOR, These birds generally build on the The commerce and manufaetures banks of a running stream, either a which have their chief seat in the mong the roots of the hazel-bush or lower ward of Lanarkshire, in parts in the decayed trunk of a tree. The of the respective counties of Renfrew, first wall is composed of strong grass Dumbarton, and Ayr, and of which or the small branches of trees; these the city of Glasgow may be deemed are again lined with a coating of fine the centre and emporiuin, have eviclay: The Mavis is content with dently been attracted by local and nathese two, but the Bluckbird lines the tural pre-existing advantages. clay with fine hair or wool, and alto The great river and firth of Clyde, gether forms a most comfortable and situated on the western coast, and warm abode for its young.
even more accessible from the AtlanIn former days, when cock-fighting tic Ocean than the Mersey or the Sewas more in vogue than at present, vern, is peculiarly adapted for the the great desideratum was a game- convenient prosecution of that great cock that had been hatched by a Mag- commercial intercourse with the new pie. The being nursed by such a hemisphere, of which Glasgow has stepmother was considered as render- become the principal Scottish depot. ing the hero invincible. Yet no The circumstances which, united small degree of finesse was necessary to the demands of external commerce, to beguile the Pyet, and the being contributed to localise and to extend able to paint the hen's egg so as to the manufacturing operations of these
STATISTICAL OBSERVATIONS ON THE
COMMERCE AND MANUFACTURES
AND THE ADJACENT DISTRICTS.
districts, may be traced to the cheap- once so great, not more has reverted
er number of mercantile houses and From these physical advantages, individuals, than in its earlier times; the manufactures of this district un- and is carried on with that mixture of questionably took their rise, and the success and misfortune, which is insame causes which first attracted seem separable from extended commerce, likely to render them permanent. In- and general competition. deed, it is apparent, that to a similar A considerable trade certainly exrelative situation, and to the presence isted in the Clyde, before manufacof the very same minerals, we must tures were much cultivated in Glasascribe the local residence of the cor gow and the vicinity. But as the deresponding branchesofindustry, which mand for the finer sorts increased with have fixed themselves in Lancashire, theopulence of the colonists, astimulus Staffordshire, and Warwickshire ; and to produce these upon the spot from which have given to Manchester and whence they were exported was naBirmingham, those extensive manu, turally and gradually created. A vafactures, and to Liverpool, that wide- riety of manufactures, to emulate spread commerce, which are now in those of England, were consequently some degree rivalled at Glasgow, Pais- attempted ; some of which proved ley, and Greenock.
abortive, whilst others were gradually The commerce of the Clyde be- matured and established. It was not, gan to extend rapidly only about the however, until about the close of the middle of the last century; and the American contest, that a new manufirst intercourse of great importance facture was introduced ; which, foswas that with the North American tered in its infancy by a general recolonies, which now form the United vival of foreign commerce, has since States.
incomparably exceeded all others, both The exports were such manufac- in extent and in the investment of tures as the country then afforded; capital. and the returns were chiefly in to The cotton manufacture has inbacco, of which, at one time, more deed assumed so entirely the character was brought into the Clyde than into of a staple, that, upon its prosperity any other British river, the Thames or decline, the chief interests of the itself not excepted. The traffic was whole western districts are considered limited to few hands; and splendid to depend. To analyze, therefore, in fortunes were realized by some of the some degree, the nature, tendency, and individuals who were engaged in it. It operations of this new colossal, alwas, however, suspended by the war, though depressed manufacture, will which terminated in the separation of be admitted to be of paramount imthe colonies from the Parent State. portance in every inquiry into the
At the peace of 1783, the intercourse manufacturing state of Scotland. with America was re-opened, and The origin of the British manuhas ever since formed a considerable facture of cotton goods must be trabranch of the commerce of the Clyde; ced to the invention of the spinning subject only to the occasional suspen- machinery. This wonderful mechasions produced by political contingen- nical improvement was introduced into cies, and to the more frequent stagna- Scotland at the very period alluded to; tions arising from glutted markets. and various cotton-mills were erected,
The American trade since 1783 has where waterfalls could be found sufbeen incomparably more general than ficiently powerful to give motion to formerly, both in its channels, and in the extensive range of machinery its returns ; and of the tobacco trade, which is required. These waterfalls