When I first began to have to do with an insurance company's investments, I found I had to gather from many quarters the elementary information necessary to enable me to understand in a general way the work I had to do. A great deal has been published since then to remedy this state of matters, but it seems to me there is still room for a treatise of this kind giving the outlines of the subject without going into much detail. Although I have had in view principally the requirements of a beginner, I venture to hope that even those who are further advanced may find something of value in my notes.