The Colorado School of Mines at Golden has commenced construction of a new $775 000 science hall as part of a $2.5 million expansion program supported by federal, state, and private sources. The building, a three‐and‐one‐half‐story structure to be used predominantly for the teaching of physics, will replace the 88‐year‐old former Golden public school building which now houses the college's Physics Department. It is expected to be ready for occupancy in the summer of 1963.