Berner ran dozens over the next few years, gradually refining the format and method, optimising the retreat for the "weekend truth-seeker".

He has been doing this for 40 years, during which time the work, although gradually refined in little ways, has stayed essentially the same.

Thus he gradually refined his technique, adjusting times and temperatures to the tightest tolerances to produce more consistent results than most other practitioners.

Based on macro- and micromorphology, later authors gradually refined the generic concept of Lepiota.

He plays the tape again and again throughout the movie, gradually refining its accuracy.

Wright gradually refined the R-540, using suffix letters to indicate successive versions.

In his professional career from 1940s to 1950s, he gradually refined his European modernist education into an appropriate local architecture design.

Tough, trial-and-error, sometimes live-or-die work like this was gradually refined into the intellectual and rarefied pursuit we call science.

If anyone else had spent years batting away at it, gradually refining it, they would be in the position we are today.

On some of the rough mixes that have appeared on bootlegs, the time-consuming overdubbing on the song is apparent, as Lennon gradually refined the arrangement.