XIV

PREFACE.

The superior accuracy with which theplates are drawn and engraved, will, it ishoped, appear to competent judges at thefirst sight; for the perfecting of which noexpence of time or labour hath been spared.The celestial globe is improved by the addi-tion of several thousand stars more thanhave appeared upon any globe hitherto pub-lished j all the latest discoveries in geographyand astronomy are in both of them strictlyfollowed, and many new lines and circlesare inscribed, the use of which will be fullyexplained hereafter.

In the treatise, we have made choice ofthat method of finding the times of equinox,which is the most modern and simple; andwhich perhaps gives the truest mean lengthof a tropical year; that the young studentmay with greater ease and pleasure be madeacquainted with the first principles, and fromthem be carried on to the more abstruseparts of astronomy.

To render this book as extensively usefulas possible, I have endeavoured, with allthe clearness I am master of, to expressboth my own and the sentiments of otherauthors on the fame subject; and I think

it