The continuing, widespread ( and neglected) importance of improvements in mechanical technologies 3 T9 `% o- ?" A$ c. I4 e% H( f 6 N9 u2 `1 a& f+ y t3 ] f, y4 i# \
Parimal Pate1 and Keith Pavitt 4 s% `+ u* S1 U5 Q2 H7 gScience Policy Research Unit, Unil~ersity of Sussex, Falmer, Brighton BNI 9RF, UK