highest of terrestrial creatures, was about to appear. With the tertiary a new order of things arises it has been said that it possesses scarcely a species in common with the preceding age,that two planets could hardly differ more in their natural productions; and this break in the law of continuity is the more remarkable, as hitherto some of the newly-created animals were always introduced before the older was extinguished. It was a period of rest and tranquility; an exultant and abounding age. Creatures of a high order, the largest of the land mammalia, moved through the luxuriant herbage, or enjoyed the shady coolness of the riverside. And still, with the ever-widening dawn, the resemblance to our own world increased. The stately ruminants of the forest--the elk, the stag, and the bison appeared. The horse waited for his rider, and the steer for the yoke of the husbandman: flowers, like our own, enamelled a thousand fields, and the lark, as now, filling the air with song, soared upward to the gates of heaven.

And thus, the conditions of vitality being there, it is difficult to conceive of life itself being absent. Everything around us, the blade of grass, the drop of dew, teems with living beings. Life is enjoyed everywhere to the uttermost. There is no space lost. And not only is life present, but life advanced to the farthest degree of perfection which the supplied conditions will allow. The elements being given, the organism is the unfailing product, and the Promethean spark kindles at once into being. If human life then was possible during this period, we may rest assured that human life was there.

And they, the dwellers in their island-home, how lived they? What was their history? May we believe with Plato, that they became prosperous, rich, powerful,-were ruled by wise kiugs, received tribute from the neighbouring islands, and had long years vouchsafed to them of peace and plenty? And, finally, after sending out migratory swarms eastward, and perhaps westward, how did their island disappear? Was it submerged slowly? Or did it sink suddenly in ruin? We cannot tell. All is dark and uncertain. Yet, with the onward march of science, the day

may perhaps come when its historic actuality will be made plain as the fact of its geological existence. Whatever the power and greatness of the old Atlantids, all now is vanished as a dream, lost and engulfed in a barren wilderness of waters. Festivals, processions, the meetings in the market-place, and uproar of congregated thousands, all is silent now. The ocean keeps its secret: summer and winter, sleet and sunshine, pass over its surface, but no sound or echo comes to tell of the sleepers below. Yet here, haply, were human affections and friendships, and all the incidents and realities of life. And when the suddenness of desolation fell upon them, it must have been with no ordinary pang that these children of the morning resigned the rich blessings they enjoyed, and descended into that darkness where as yet no Teacher had gone before. Buried thus in the lava and scoriæ of volcanic action, who can tell what subtle agencies of nature have since been at work? Who can say whether the infiltrated fluid, charged with calcareous or silicious earth in solution, may not, in the interval preceding the final submersion, have lapidified these sleepers, have turned them into stone, like the fossils and reliquiæ which form the study of the curious? If so, it may be that when, in the oscillations of the earth's crust, the Island of Atlantis, covered with its subsequent deposits, again rises to the surface, some future geologist may lay bare the secrets of that last convulsion, may gaze with reverence on the first-born of our race, and again expose to air and sunshine the reveller with his rose-wreath, the hierarch with his staff, and the mailed monarch with his sceptre and his crown.

PAPER IX.-ON THE SECULAR CHANGE OF MAG

NETIC DECLINATION IN CANADA, FROM 1790
TO 1850.

FROM THE RECORDS OF THE DEPARTMENT OF CROWN LANDS.

By E. T. FLETCHER, Esq.

(Read before the Society, 17th May, 1865.)

It has occurred to me that an examination of the various Returns of Survey of record in the Department of Crown Lands might be, to some extent, useful in furnishing additional data for the solution of that interesting problem in magnetic science which proposes to determine the limits, causes, and elements of the secular deflections of the magnetised needle. It is obvious that reliable observations in different parts of Canada, if obtainable, would be of great value, from the immense extent of the colony from north-east to southwest, nearly at right angles to the presumed direction of the magnetic isogonal lines. The records of the Department I have mentioned, comprising, as it does, the old Surveyor General's Offices for Upper and Lower Canada, and constituting, with its other formerly independent branches, rather a federation of offices than one Department alone, reach back for a full century; nay, even further, if we include the ancient seigniorial concessions and various special land descriptions of a date anterior to the conquest. As a surveyor attached to the Department for the last four and twenty years, I could not be blind to the possibility of some good from this source, though a closer examination of the older records has, it is true, somewhat lowered the expectations I originally entertained by shewing me how little, comparatively, of substantial and reliable fact was obtainable from these voluminous files, and that for these reasons:-In the first place, by far the greater part of the older surveys were performed by the needle alone, without

reference to the true or astronomical bearing; in these, therefore, there was no mention of magnetic variation or declension; the only exception was where the side-lines of seigniories were concerned, which, by the old French arrêts or réglements, were required to have a fixed astronomical bearing-that is, due northwest and south-east on the St. Lawrence, and nord-quart de nordest, or north 124° cast, on the Ottawa. In these cases the surveyors were compelled to lay off a true meridian, and thus the variation was not unfrequently noted. In the second place, some surveyors seem to have carried the variation with them from one part of the country to another, and, having compared their circumferentor with the meridian stones set up at Quebec and elsewhere, to have travelled off with the variation thus obtained as a fixed and unchangeable element, good for all parts of the district. Thus the surveyor intrusted, some seventy years ago, with the survey of the Yamaska, the Richelieu, or the Chateauguay rivers, might possibly start from Quebec by batteau (for as yet steamers were not) for Three Rivers, and, having spent perhaps a week or ten days in the voyage, if the wind was unfavorable, would, on landing at the latter town, compare with every possible minuteness and care the magnetic bearing shewn by his circumferentor with the true north and south line given by the meridian stones. This done, he formally notes in his field-book or journal: "je trouve donc que la variation de non instrument est de dix degrès trente minutes;" and this ten degrees thirty minutes goes with him throughout an operation of perhaps many miles in extent as a constant and unalterable companion. Yet far be it from me to decry the merits of these patriarchs of the profession. Though some. times a little shaky in theory, in practice they were frequently admirable. I have myself had frequent occasion to verify the accuracy of their work, and the journal of their operations shows a wonderful dexterity, quick-wittedness, and fertility of resource under difficulties. At times on the verge of starvation, or annoyed by the wild animals which at that time swarmed everywhere, or running dangerous rapids on small rafts, and losing perhaps some

one of the party, they seem to have been always prompt, fearless, and uncomplaining, knowing their duty, and striving, like honest men, to perform it faithfully and well. Other causes of unsatisfactory observations are to be found in the entire ignoring the diurnal and annual variation, and in the imperfectness of the instruments themselves. Local attraction and disturbances have also been a frequent cause of error. As a proof of the liability to error from observed declination, where the diurnal or annual variation is not taken into account, I would only instance the annual variation, greatest, as is known, in June and July, and least in December and January. From the records of the Toronto observatory it appears that in January, 1841, the observed declination was 1° 11' 1"; in June and July of the same year it was 1° 17'; while in the following year, 1842, the declination was in January 1° 14', and in June and July 1° 20'. Thus the declination at Toronto, though increasing from year to year, is yet greater in June and July, 1841, than in January, 1842.

The observations of later days are free from many of these errors. The instruments now in use arc of improved make and more accurate construction. The causes which influence the local and periodic disturbances of the needle are better understood and more clearly appreciated. The course of study, also, now required from candidates for the profession, is of wider scope than formerly. A reference to the 77th chapter of the Consolidated Statutes will shew the various branches of physical and exact science which form part of the course. Each candidate is subjected to two examinations one on mathematical subjects alone, before being indentured; and a second, embracing all subjects, at the expiration of his term, and before receiving his diploma. There appears, therefore, reason to believe that in future, as now, magnetic observations of this kind may be received as, in general, reliable.

Towards the close of the last century, fixed meridian stones were laid down at Quebec, Three Rivers and Montreal. They are frequently referred to in the old returns of survey, and must have been of great use in determining the secular charge of declination in those several localities.