Kerguelen’s voyage to the north. 74* is always a great inflabiiity in the winds; they however moftly blow N. E. and S. E. Thefe three days were employed in reconnoitering the coaft, and in taking bearings, and making remarks on the diredion of the fhores. The twenty-firfl: the wind was W., and not perceiving more than two or three veffels, I bore N. N. W. to feek the fleet. At ten o’clock in the morning, fix or feven leagues from the land, I perceived the fea white before me to the horizon. The two pilots for thofe coafts which I had on board allured me that this whitenefs was nothing but the fea itfelf which was frozen. I continued my courfe N. N. W. to take a nearer view, and getting within half a league of it I fatisfied myfelf, the fea appearing wholly frozen in one folid mafs, extending from the N. W. of the compafs as far as to the North Cape, which was at E. S. E. I tacked immediately to avoid the danger, and warn the fleet of it. The year before the flrait between Greenland and Iceland had been entirely frozen over all the fummer. I cannot here refrain from making fome reflexions on this frozen fea, and on the mountains of ice which are found on the north fea during voyages from Europe to North America, and fometinies on doubling cape Horn. Some have been met with which, like iflands or rather continents, appear to be many leagues in length, and elevated more than two hundred feet above the furface of the water. How are we to account for thofe enormous maffes ? Every body knows that the total ceflation of motion in infenfible particles caufes cold, and that cold is the immediate and true caufe of the formation of ice; that there are other fubordinate and accidental caufes, fuch as fpirits of fait and nitre, which, expanded in the air, occafion even in the midfl: of fum- mer fuch extreme cold as to freeze lakes and rivers. Thus the north wind in the northern hemifphere, and the fouth wind in the fouthern hemifphere, contribute to cold and the forming of ice, becaufe they bring from the poles corpufcles or cold particles, which penetrating the furfaces of bodies fufpend the motion of the imperceptible par- ticles. 1 lhall enter into fome detail to develop the different caufes of cold and ice. I compute, in the firfl: place, on the exiitence, as a bafe, of an cetherial matter, ex- tremely fubtle and active, which furrounds and penetrates in a larger or fmaller degree all liquid fubftances ; if its motion be leflened, its fpring become weak, fo that it be no longer able to overcome the reliftance of the integral parts of the liquid (that is, W'hicht caufes the cold), ice will be produced j thus the formation of ice is the immediate refult of the diminifhed motion of the fubtle matter which conftitutes fire and heat. Let us now examine the accidental caufes. Salt, nitre, faltpetre, thefe make up the firfl; accidental caufe of the formation of ice. In places where they abound the air be- comes loaded with them, they penetrate the pores of liquids like fo many fmail wedges, they clofe the paffages again!! the entrance of the grofs particles of the fubtile matter, flop the motion of the imperceptible particles of liquids, and thus harden and convert them into ice. It is thus that in certain caverns, whofe neighbourhood abounds in nitre, pyramids of ice are formed, as in a cave near the village of Chaux, five leagues from Befan$on, where three were found in the month of September 171 x, of fifteen feet ia height *. Wind I confider to be the fecond caufe of ice. Many perfons imagine the wind to be an obftacle to the formation of ice ; it is true,, when jt has much hold of an extenfive furface of Water, as of rivers, lakes, and feas, it frequently hinders them from freezing while it continues to agitate them, and deprives the integral parts of the liquid from uniting together, notwithftanding it is certain that for the moft part wind ought to accelerate freezing, as I am about to explain. In cold weather, approaching to froft, a dry wind, fuch as the N. E. in our climate, contributes to * Hiltoire de l’Acad. 1712. p. 22.

(1) Band
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(77) Saurblað
(78) Saurblað
(79) Band
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(81) Kjölur
(82) Framsnið
(83) Kvarði
(84) Litaspjald