Are modern fast bowlers faster than their predecessors?

Scyld Berry, writing in the Daily Telegraph, says it could be impossible to establish whether modern fast bowlers are faster than their predecessors two decades ago, as no objective measurements have been made through the ages.

While average speeds have increased, I don’t think the speed of elite fast bowlers at their most inspired or peak moments, when everything has clicked, has perceptively increased in recent decades. So average speeds, yes. Peak speeds, no. Tim Bresnan’s average speed during his England career, I would guess, is higher than that of Fred Trueman during his England career. Who the better bowler is, again, is another matter.