The Propositions of Figure "T"

For a clear and orderly perception of the propositions of T., note that as T. is divided into five triangles and each angle into three terms, so are its propositions distinctly divided. There are three propositions for each principle of an angle, and as each principle is further subdivided into three terms, each term has three propositions. Thus, each angle contains four times three, or twelve propositions and consequently each triangle contains thirty six propositions, and as there are five triangles in the figure, this makes one hundred and eighty propositions in all. This part deals with the said propositions, beginning with the propositions of the first and most noble principle, followed by the other principles in sequence.