The start of Quaestiones is definitely after 8 July 1661, the date on which Newton arrived at Trinity College. It is also definitely before 9 December 1664, on which day (and the following) he made notes of his observations of a comet. Other datings of the first entries are based on his handwriting—which changed drastically between the early notes of 1661 and later notes which can be dated independently to 1665. The transitional handwriting which characterizes the early parts of Quaestiones can only be independently dated to roughly 1664. This was written during a period when Newton was actively developing the notion of calculus, but mathematics made no real appearance in this notebook.