The first part was on Natural Philosophy; the second part on Hydrodynamics; the third part on Physics; and the fourth part on Mathematical Elements. Each had a Greek or Latin motto prefixed, and the following advertisement to the first part was printed: In order to adapt the delivery of these lectures as much as possible to the convenience of different persons who may be disposed to attend them, they will be divided into three parts of nearly equal magnitude, and in great measure independent of each other. Two parts will be delivered in succession on Mondays and Wednesdays, at two o’clock, and the third on Friday evenings at eight. And in future winters, each part will be taken in turn for the evening lecture, so that the whole course may be heard at either hour. The fourth part contains all the preliminary knowledge that is necessary for those who may wish to enter mathematically on the various subjects of the lectures; it will save considerable pains in consulting other authors, and the most experienced may often find it convenient for occasional reference. It was the more desirable that something of this kind should be inserted, as mathematical arguments will be avoided as much as possible in the lectures; and for this reason the demonstrations which occur in the syllabus are distinguished from the principal text by a smaller type, and a separate place in the page. In a future edition a fifth part will probably be added, containing a catalogue of the best authors, with references to their works upon each subject. One acknowledgment must, however, be inserted here for the extensive use that has been made of the valuable articles contributed by Professor Robison to the ‘Encyclopædia Britannica.’ Royal Institution, Albemarle Street, January 19, 1802. The volume forms an octavo of upwards of 250 pages; and it is quite evidence enough that the matter, no less than the manner of the lectures of Dr. Young, were more fitted for Cambridge than for the Royal Institution. Dr. Paris thus contrasts Davy’s manner with that of Young: To judge fairly of the influence of a popular style we should acquaint ourselves with the effects of an opposite method, and, if an appeal be made to experience, I may very safely abide the issue. Dr. Young, whose profound knowledge of the subjects he taught no one will venture to question, lectured in the same theatre, and to an audience similarly constituted to that which was attracted by Davy, but he found the number of his attendants diminish daily, and for no other reason than that he adopted too severe and didactic a style. The first afternoon lecture was given by Dr. Young, on Wednesday, January 20, 1802, and the first evening lecture on Friday, January 22.