Until quite recently, I had been in tlie habit of thinking, and indeed sometimes of teaching, that when the obstetric forceps slipped off the head during the operation of extraction, the instrument had been unskilfully applied. Within the last month I have changed my views on this point entirely. Up till October of this year I had no personal experience of the accident, but during that month I ...

The terms “curriculum differentiation” and “School Based Curriculum Developemnt” occur frequently in the literature.The former is used to describe how individualised instruction can be developed for individual students. The latter refers to students too but in the wider context of the total school population. What has not been realized until quite recently is the overlap between the two terms a...

The present paper investigates arc-transtive graphs in term of their stability, and shows, somewhat contrary to expectations, that the property of instability is not as rare as previously thought. Until quite recently, the only known example of a finite, arc-transitive vertex-determining unstable graph was the underlying graph of the dodecahedron. This paper illustrates some methods for constru...