Letter from Robert W Begg, Dalhousie University, Halifax, Nova Scotia to Howard Walter Florey Last official date on which he can supplicate for D Phil is July 1949 - thesis will not be ready then - delay has been partly because his supply of mice was cut off by fire which destroyed the Jackson Memorial Laboratory - comments on this and on the amount of teaching he has had to do - would be grateful if he could be granted an extension - greatly in Florey's debt for his year at Oxford. 10 January 1949