In that Tract he observes, first in _General_, that this second _Comet_ is contrary to the precedent, almost in all particulars: seeing that the _former_ moved very swift, _this_, pretty slow; _that_ against the Order of the signs from East to West, _this_, following them, from West to East: _that_, from South to North, _this_, from North to South, as far as it hath been hitherto, that we hear off, observed: _that_, on the side opposite to the Sun, _this_, on the same side: _that_, having been in its _Perigee_ at the time of its Opposition, _this_, having been there, out of the time of its Conjunction: where he taketh also notice, that this _Comet_ differs in brightness from the other, as well in its Body, which is far more vivid and distinct, as in its _Train_, whose splendor is much greater, since it may be seen even with great _Telescopes_, which were useless in the former, by reason of its dimness. After this he descends to particulars, and informs us, that he began to observe this Comet _April_ the second, and continued for some days following, and that as soon as he had made three or four Observations, he resolved to try again an _Ephemerides_; but that, having no instruments exact enough, and the Comet being in a place, destitute of Stars, and subject to Refractions, he feared to venture too much upon Observations so neer one another, since in such matters a perfect exactness is necessary, and wished to see some precedent Observations to direct him: which having obtained, he thereby verified what he had begun, and resolved to carry on his intended _Ephemerides_, especially being urged by his Friends, and engaged by his former undertaking, that so it might not be thought a meer hazard, that made him hit in the former; as also, that he might try, whether his Method would succeed as well in slower, as in swifter Comets, and in those, that are neer the Sun; as in such as are opposite thereunto, to the end, that men might be advertised of the _determination_ of its use, if it could not serve but in certain particular Cases. He relateth therefore, that he had finished this New _Ephemerides_ _April_ the sixth, and put it presently to the Press; in doing of which, he hopes, he hath not disobliged the Publick: seeing that, though we should loose the sight of this Star within a few days, by reason of its approach to the Sun, yet having found, {38} that it is always to rise before the Sun, and that we may again see it better, when it shall rise betimes, towards the end of _May_, and in the beginning of _June_, if the cleerness of the Day-break hinder us not; he thought it worth the while to try, whether the truth of this _Ephemerides_ could be proved.