Erratum

with similar terms. I have been prevented from calculating these terms, and from extending the former so as to include the parts depending on the secular variations of the elements, and even from examining some parts so carefully as I could wish, by the excessive labour attending these investigations. The term calculated is of the 5th order; and I believe it may be fairly stated that the labour of the calculation is twenty times as great as for the long inequality of Saturn, and far greater than for any term hitherto treated of. I shall resume the investigations as soon as I have sufficient leisure and spirits: and I propose then to lay before the Society a more detailed account of the calculation. G. B. Airy. Trinity College, December 16th, 1827. Erratum in the Paper on Mr. South's observations. In the Phil. Trans. for 1827, page 69, line 16,—for $1^\circ 30^\circ$, $4^\circ 30^\circ$, $7^\circ 30^\circ$, $10^\circ 30^\circ$—read $1^\circ 15^\circ$, $4^\circ 15^\circ$, $7^\circ 15^\circ$, $10^\circ 15^\circ$. This error has not affected the calculations.