Proceeding by decades in the same way as before, the entries on each of the two sides (denoted by _C_ and _BD_) which existed from 1755 to 1822 were in 1755, nineteen and ten; in 1765, four and six; in 1775, twenty-one and twenty-four; in 1785, eighteen and twenty-nine; in 1795, twenty-nine and seventeen; in 1805, forty-two and twenty-six; and in 1815, fifty-one and thirty-six. From 1822 to 1872 there were three sides (denoted by _C_, _BD_, _A_): the normal entries on these were in 1825, forty-two, fifty-five, forty-one; in 1835, forty, forty-five, fifty-three; in 1845, fifty, sixty-eight, forty-nine; in 1855, fifty-three, forty-eight, fifty; and in 1865, fifty-eight, nineteen, sixty. Since 1872 there have been four sides (denoted by _C_, _B_, _D_, _A_) which were made approximately equal: the normal entries on these were in 1875, forty-one, forty, forty-four, forty; in 1885, forty-nine, forty-four, forty-five, forty-eight; in 1895, forty-eight, thirty-eight, fifty, fifty-one; and in 1905, fifty, fifty-three, fifty, fifty-seven. Until 1755 the number of pupils in residence in any one term assigned to an individual tutor was not large, and a tutor interested in any particular aspect of a subject likely to be studied was generally available: hence it was usually possible for a tutor to give personally the teaching and guidance required by his pupils. There were then no lecture-rooms in College, so probably all instruction was given in the tutor's rooms and was informal in character. With the establishment in 1755 of sides, this system of teaching required modification, and in the course of the latter half of the eighteenth century it became the custom for a tutor to supplement his teaching by the services of another fellow or other fellows. These officers, known as Assistant-Tutors, were appointed and paid by individual tutors; they lectured regularly, took an important part in the life of the Society, and occupied a recognized position. A marked development of the system of formal lectures is indicated by the erection in 1835 of a block of four large and four medium-sized lecture-rooms. No other important changes were made for another thirty years, and until 1868 instruction remained normally organized by sides; indeed it was only by arrangement that lectures on one side were open to men on the other sides, though in fairness it must be added that an arrangement for throwing them open was made as a matter of course whenever it seemed desirable. The retention to so late a date of appointments by sides was due to the fact that the finances of the four sides were then kept as separate accounts.