These patterns slowly drift, the animals' appearance changing imperceptibly as Turing predicted.

But there was no mention of Charity leaving, although her duties were changing imperceptibly from nurse to nursemaid.

Their positions would change imperceptibly over the course of the next... "Twelve days?"

It even changes imperceptibly because you - and not another - are watching it.

She drew closer, her face changing imperceptibly in the play of the light.

For instance, by imperceptibly changing the clarity of an image, room could be made to hide a coded message.

It included all possible memories, changing imperceptibly from one to another without the faintest hint of jarring.

As he ap-proached the last wall, near a dank corner, the sound of his tapping changed almost imperceptibly.

But Lara evaded his question, imperceptibly changing the subject.

Continually different, yet always the same, the haze-shrouded wastes of reed and water had been changing imperceptibly.