than those found by Dr. Brinkley, they appear to be equally independent of accidental error. The author, however, is not inclined to refer the cause of the differences to parallax, for they are sensibly increased by direct comparison with an opposite star, as with Capella, in which the maximum of parallax is nearly as great as in α Aquilæ; and it is very unlikely that the parallax of one star should exceed ·5″, and that of the other be an insensible quantity. Moreover, all these stars pass the meridian about the time of the winter solstice at their maximum of parallax; and in proportion as stars do not possess this property, both the Astronomer Royal and Dr. Brinkley either find a much smaller discordance, or none at all; the author accordingly is inclined to look for some explanation of the difficulties in this peculiar circumstance.
Tables are annexed to this paper, showing the method of computing the equation, or index error, applicable to the north polar distances.
Being induced last autumn to suspect that the discordance in favour of parallax, before met with, might arise from variation of temperature, the author endeavoured last winter to keep the interior and exterior of the Observatory of the same temperature, which the mildness of the season easily enabled him to do. From the 1st of July 1816 to March 1817, the index error of the instrument suffered no variation; and therefore the objections urged by Dr. Brinkley were done away. Under these circumstances the observations of α Lyræ, γ Draconis, α Cygni, and α Aquilæ, showed no indication of periodical variation. Whether the fixed instruments lately erected for this investigation will confirm the above result remains to be determined.
Having been requested by Sir Joseph Banks carefully to preserve such organic remains as might be found in the quarries whence the supplies of limestone for the break-water at Plymouth are drawn, Mr. Whitby, who has the superintendance of the undertaking, transmitted, in November 1816, a box of fossil bones, which form the subject of the present communication.
According to Mr. Whitby's report, they were found in a cavern of the solid limestone rock, fifteen feet wide, forty-five long, and twelve deep. It was filled with clay, and the bones lay about three feet above the bottom. This cavern is about seventy feet below the
