2 O DEDICATIOff. wherein those regions are copied out in a narrow compass, and exhibited in one view to the eye I' If we look upwards with David to the worlds above us, we consider the heavens as the work of the finger ofGod, and the moon and thestars which he hath ordained. What amazing gloriesdiscover themselves to one sight? What wonders of wisdom are seen in the exact regularity of their revolutions? Nor was there ever any thing that has contributed to enlarge my apprehen- sions of the immense power of God, the magnificence of his creation, and his own transcendent grandeur, so much an that little portion of Astronomy/ which I have been able to attain. And I would not only recommend it to young students for the same purposes, but I would persuade all mankind (if it were possible) to gain some degrees of acquaintance with the vastness. the distances, and the motions of the planetary worlds on the same account. It gives an unknown enlargement to the understanding, and affordsa divine en- tertainment to the soul and its better powers. With what pleasure and rich profit would men survey those astonishing spaces in which the planets revolve, the hugeness of their built, and the almost incredible swiftness of their mo- tions ? And yet all thesegoverned and adjusted by such unerringrules, that they nevermistake their way, nor lose a inmute oftheir time, nor change their appointedcircuits- in several thousands of years ! When we muse on these . things we may lose ourselves inholy wonder, and cry out with the Psalmist, Lord what is man that thou art mindful of him, and the son of man that thou shouldest visit him It was chiefly in the younger part of my life indeed that these studies were my entertainment; and being desired both at that time, as well assince, upon some occasions, to lead some young friends into the knowledge of the first principles of Geography and Astronomy, i found no treatise on those sub- jects written in so very plain and comprehensive a manner as to answer my wishes: Upon this account I drew up the following papers, and set every thing in that light in which it appeared most obvious and easy to me. I have joined the generalpart of these two sciences together: What belongs particularly toeach of them is cast into distinct sections. And I wish, Sir, you would present the world with the special part of astronomy drawn up for the use of learners in the most plain and easy method, to sender this work more complete. Most of the authors, which I perused in those days when I wrote many parts of this book, were of older date: And therefore the calculations and numbers which I borrowed from their astronomical tables, cannot be so exact as those with which some later writers have furnished us : For this reason the account of the sun's place in,the ecliptic, the declination and right osceni-. siso of the sun and the stars in some parts of the book, especially in the soh), non of some of the problems in the 20th section, may perhaps need a little correction ; though I hope the theorems still appear true in the speculation, and the problems so regular and successful in the practice as is sufficient for a learner. However, to apply some remedy to this inconvenience, there are added at the end of the book some later tables, which are f'or'med according to the celebrated Mr. Flamstead's observations. I have exhibited near forty problems to be practised on the globe, and thirty-five more of various kinds, to be performed by manual operation with the aid of some geometricalpractices. These were very sensible allurements tomy younger enquiries into these subjects, and 1 hope they may attain the sameeffect upon some of my readers. it was my opinion that it would be a verydelightful way of learning the doctrine and uses of the sphere, to have them explained by a variety of figures or diagrams; this is certainly much wanting in most authorsthat I have peril. sed. I have therefore drawn thirty figures with my own hand, in .order to reader the description of every thing more intelligible.
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