The Planetary and Stellar Worlds

to comply with the wishes of the astronomical society, that he should perform for them the important services on which the future success of this new enterprise in no small degree depended. His high character, his advanced age, the length of the journey, the inclemency of the season, all combined to exhibit to his countrymen the depth of his interest in a cause which could induce such sacrifices.

After the laying of the corner-stone, the lateness of the season, and other causes, induced a suspension of the work on the building for the winter; and it was not resumed until May, 1844. In the mean time, after incredible difficulty, the entire amount called for in the payment for the great telescope, was collected and remitted; and the society was left with scarcely a dollar of available means, to commence the erection of a building which, according to the plan, would cost some seven or eight thousand dollars.

It was believed that the intelligent mechanics of Cincinnati would lend their powerful aid in the accomplishment of an enterprise which had progressed far enough to give some con fidence in its ultimate success. With little or no means the building was commenced, trusting to activity and perseverance to supply the means as the work progressed. During the first week but three workmen were employed; but by the commencement of the next week the funds had been obtained to pay these, and to double their number. In six weeks not less than one hundred hands were at work on the hill-top and in the city. Mechanics of all trades subscribed for stock, and · paid their subscription in work. The stone of which the building is erected, was quarried from the grounds of the society. The lime was burnt on the hill, and every means

was adopted to reduce the necessary expenditure. Payment for stock in the society was received in every possible article of trade; due-bills were taken, and these were converted into others which would serve in the payment of bills.

In this way the building was reared, and finally covered in, without incurring any debt. But the conditions of the bond, by which the lot of ground was held, required the completion of the observatory in two years from its date; and these two years would expire in June, 1845. It was seen to be impossible to carry forward the building fast enough to secure its completion by the required time, without incurring some debt. My own private resources were used, in the hope that a short time after the finishing of the observatory would be sufficient to furnish the funds to meet all engagements. The work was pushed rapidly forward. In February, 1845, the great telescope safely reached the city of Cincinnati; and in March the building was ready for its reception. I had now exhausted all my private means, and, to increase the difficulty of the position in which I was placed, the College edifice took fire and burned to the ground. My ordinary means of support were thus destroyed at a single blow. I had engaged to conduct the observatory, without compensation from the society, for ten years, in the hope that my college salary would be sufficient for my wants. It was impossible to abandon the observatory. The college could not be rebuilt, at least for several years, and in this emergency I found it necessary to seek some means of support, least inconsistent with my duties in the observatory. My public lectures at home had been comparatively well received, and after much hesitation it was resolved to make an experiment elsewhere. For five years I

nad been pleading the cause of science among those little acquainted with its technical language. I had become habituated to the use of such terms as were easily understood; and probably to this circumstance, more than to any other one thing, am I indebted for any success which may have attended my public lectures. To the citizens of Boston, Brooklyn, New York, and New Orleans, for the kindness with which they were pleased to receive my imperfect efforts, I am deeply indebted. My lectures were never written, and no idea was entertained of publishing a course, until the partiality of my friends induced me to attempt this experiment.

Such are the circumstances under which this effort to trace the career of the human mind, in its researches among the stars, has been undertaken. No one science, perhaps, so perfectly illustrates the gradual growth and development of the powers of human genius. The movement of the mind has been constantly onward-its highest energies have ever been called into requisition-and there never has been a time when astronomy did not present problems not only equal to all that man could do, but passing beyond the limits of his greatest intellectual vigor. Hence, in all ages and countries, the abso lute strength of human genius may be measured by its reach to unfold the mysteries of the stars.

It will be seen that in the following lectures one single object has engaged the attention of the writer-the structure of the universe, so far as revealed by the mind of man. The uses of science have in no way been considered. The effects on the mind, on society, on civilization, on commerce, on religion, have not been permitted to mar the unity of the original design. The onward, steady, triumphant march of

mină, in its study and exploration of the universe of Gott, ha been my only object, the single theme of the entire series.

I may be pardoned for a single word, before taking leave of the reader, touching the condition of our country with refer ence to practical astronomy. Within a few years an entire revolution on this subject has occurred. The reproach which once rested on the United States has been removed. Several magnificent instruments now adorn the observatories of the New World, and the contributions of American astronomers, to science, are beginning to change the scientific character of our country in the eyes of the old World. It is gratifying to know that several institutions, with ample means of support, now exist in our country, to which the interests of American science are committed with entire confidence. The observatories at Washington, Cambridge, Philadelphia, and Georgetown, are amply provided with instruments, and an efficient corps of observers are constantly occupied in their use.

For a long time to come, one principal object will engage the instruments of the Cincinnati observatory, viz., the explo ration of the heavens south of the equator, and the re-measurement of Strüve's double stars in that region. Should this work progress but slowly, let it be remembered that the director of the observatory has no assistant, out of his own immediate family, and must devote a large portion of his time to other duties, far more closely allied to the earth than the stars.

Cincinnati Observatory,

Mount Adams, May, 1848.

TABLE OF CONTENTS.

LECTURE I.

AN EXPOSITION OF THE PROBLEM WHICH THE HEAVENS FRE

SENT FOR SOLUTION.

FIRST revolution of the Heavens witnessed by man, 18. The

curiosity excited and its effects, 19. Object of the course, 20.

The astronomer lives in all ages, 22. First problem to distinguish

between real and apparent motion, 23. The relations of the sun,

and earth, and moon, 24. The wandering stars or planets, 25.

Fixed stars, points of reference, 27. Complexity of the planetary