00342nam a2200133 a 4500008004100000050001600041100001900057245004100076246002300117250001200140260002500152300002200177350000900199120416s1954    ||||||||||||||||| ||    u  aTH 7960 Wal  aWalsh, J. W. T10aTextbook of illuminating engineering  aintermediate grade  a2nd ed.  aLondonbPitmanc1954  axii, 202p. : ill.  a0.00