Chronometers from Erebus and Terror.

The chronometers of all the whale ships were brought to Mr. Mitchell, on their return from a voyage, to be "rated," as it was called.

The piano was duly removed and placed in an upper room called the "hall," where Mr. Mitchell kept the chronometers, where the family sewing was done, and where the larger part of the books were kept,a beautiful room, overlooking "the square," and a great gathering-place for all their young friends.

Chronometers were not, by any means, in as general use at the period of our tale as they are to-day; and the deacon abhorred the expense to which such an article would have put him.

"For the determination of the longitude of Valencia, which was carried out in this year, various methods were discussed, but the plan of sending chronometers by mail conveyance was finally approved.

From London to Liverpool the chronometers were conveyed by the railways, from Liverpool to Kingstown by steamer, from Dublin to Tralee by the Mail Coaches, from Tralee to Cahersiveen by car, from Cahersiveen to Knightstown by boat, and from Knightstown to the station on the hill the box was carried like a sedan-chair.

Thirty pocket chronometers traversed the line between Greenwich and Kingstown about twenty-two times, and that between Kingstown and Valencia twenty times.

Transits were observed and chronometers were interchanged when the temperature was lower than 19° below zero: and when the native assistants, though paid highly, deserted on account of the severity of the weather, the British officers still continued the observations upon whose delicacy everything depended.

reference to the re-determination of the longitude of Valencia, it is stated that "The concluded longitude agrees almost exactly with that determined by the transmission of chronometers in 1844; and entitles us to believe that the longitudes of Kingstown and Liverpool, steps in the chronometer conveyance, were determined with equal accuracy.

'Referring to the gradual improvement in the steadiness of chronometers from 1851 to 1866, it appears that from 1851 to 1854 the 'trial number' (which is a combination of changes of weekly rate representing the fault of the chronometer) varied from 34.8s to 52.5s, while from 1862 to 1866 it varied from 21.2s to 25.8s.

I take this opportunity of stating that I have uniformly advocated the policy of offering good prices for the chronometers of great excellence, and that I have given much attention to the decision on their merits; and I am convinced that this system has greatly contributed to the remarkably steady improvement in the performance of chronometers.

I take this opportunity of stating that I have uniformly advocated the policy of offering good prices for the chronometers of great excellence, and that I have given much attention to the decision on their merits; and I am convinced that this system has greatly contributed to the remarkably steady improvement in the performance of chronometers.

The rates of the first six chronometers (in the annual trials) are published, in a form which appears most likely to lead to examination of the causes that influence their merits or demerits.

All these artists appear to entertain the conviction that the careful comparisons made at this Observatory, and the orderly form of their publication, have contributed powerfully to the improvement of chronometers.

I have long remarked that, in ordinary good chronometers, the freedom from irregularities depending on mechanical causes is most remarkable; but that, after all the efforts of the most judicious makers, there is in nearly every case a perceptible defect of thermal compensation.

The Vikings had small knowledge of taking a lunar, and of chronometers set by Greenwich time.

Such, indeed, was the state of practical astronomy in Scotland, that within these few years, a Danish vessel, which arrived at Leith, could not obtain, even in Edinburgh, the time of the day for the purpose of setting its chronometers.

Assume that they have for this purpose two identically similar and mechanically perfect chronometers, and that every difficulty of manipulation were successfully overcome.

The settings of the two chronometers would be defective, they would not show the same time, but each of them would mark the local time, proper to its own place.

I ask'd the golden sun and silver spheres, Those bright chronometers of days and years: They answer'd: "Time is but a meteor's glare,"

If he tired of consulting these guides, he could rest his eyes by gazing at the chronometers and sea compasses, the sextants, field glasses and cards strewn on a table on which stood a single volume, bound in sealskin.

Four hundred and fifty-two transit observations of heavenly bodies have been made, aided by three excellent chronometers, for the determination of the true meridian direction, most of which also served for the computation of the correct time.

Ten principal points have been determined in latitude and longitude by means of 115 sets of astronomical observations, aided by three good chronometers, and seventeen other points have been determined by triangulation with a portable theodolite.

In the course of these surveys, in order to the geographical determination of the position of the line, the latitudes of 54 points have been determined by means of 114 sets of altitudes of heavenly bodies, and the sets of subsidiary observations for time and for the determination of longitude by chronometers amount to 245.

In the course of these surveys, in order to the geographical determination of the position of the line, the latitudes of 47 points have been determined by means of 85 sets of altitudes of heavenly bodies, and the sets of subsidiary observations for time and for the determination of longitude by chronometers amount to 130.