Philip E. Heafford

Heat (Physics Topics)

By Parker, Alfred John, Heafford, Philip E., Philip E. Heafford, McArthur, T.H.

Electric Currents (Physics Topics S.)

By John L. Lewis, Philip E. Heafford

science on the march - heating and cooling

By Philip E. Heafford

science on the march - magnets and electric power

By Philip E. Heafford

science on the march - electric currents

By Philip E. Heafford