Amid all these difficulties, the computers toiled on, and finally, as the time was drawing near for the return of the comet, Clairaut, who was working in conjunction with Lalande, announced that the expected comet would be delayed one hundred days by the influence of Saturn, and five hundred and eighteen days by the action of Jupiter, and therefore fixed its nearest approach to the sun for April 13th, 1759. These results were presented to the Academy of Sciences on November 14, 1758, and as we have already seen in an earlier chapter of this book, on December 25th of that year the first glimpse of the long-expected wanderer was obtained by George Palitzsch, a farmer of Saxony. His telescope was small, his vision keen, but the enthusiasm of a devoted amateur made up for his lack of suitable equipment. Observations were made of the comet, and astronomers were soon able to prove that the perihelion passage would take place on March 13, 1759, thirty-two days before the epoch calculated by Clairaut. Such a triumphant success of the theory produced a deep impression in the scientific world, and, as Lalande enthusiastically remarked: “The universe beholds this year the most satisfactory phenomenon ever presented to us by astronomy; an event which, unique until this day, changes our doubts to certainty, and our hypotheses to demonstration.... M. Clairaut asked one month’s grace for the theory; the month’s grace was just sufficient, and the comet has appeared after a period of 586 days longer than the previous time of revolution, and thirty-two days before the time fixed; but what are thirty-two days to an interval of more than 150 years, during only one two-hundredth part of which observations were made, the comet being out of sight all the rest of the time! What are thirty-two days for all the other attractions of the solar system which have not been included; for all the comets, the situations and masses of which are unknown to us; for the resistance of the ethereal medium which we are unable even to estimate, and for all those quantities which of necessity have been neglected in the approximations of the calculation?” Twenty-five years before the comet was again due, its expected return in 1835 began to arouse the interest of astronomers, and prizes were offered by two academies for the most accurate forecast of its nearest approach to the sun. The successful competitors were Baron Damoiseau and M. Pontecoulant, and several astronomers undertook and completed the task of computing the planetary perturbations. Although the computers, as might be expected, differed slightly as to the time when the comet would make its nearest approach to the sun, yet the difference was not due to any defects in the methods of computation, but to the imperfections of the data employed, especially with regard to the unknown disturbing factor, the planet Neptune.