It slipped into the bladder and there formed the nucleus of a cluster calculus.

Dayot reports a similar formation from the introduction of the stem of a plant.

Terrilon describes the case of a man of fifty-four who introduced a pencil into his urethra.

The body rested fifteen days in this canal, and then passed into the bladder.

On the twenty-eighth day he had a chill, and during two days made successive attempts to break the pencil.