letters 33 rn x
2Z
'Transportation in "mock cities" 13E.\R S I R :
Some omission:, require comment in ! o u r otheruise exxlh:nt Special Report ( J u n e 1972) on auto engines a n d their cmiss ions. Cars arc' simply not a of niass transportation i n genuine cities such as New Y a k . Boston. and !;an Francisco. ?+lock cities such as 1-05 Angclcs and Houston, which are really cliisters of
