2 adverbs to describe how to aggregate

The work grows, slowly and gradually aggregating its parts like the child in the womb.

Dr. Wallich verified my observation, and added the interesting discovery that, not unfrequently, bodies similar to these "coccoliths" were aggregated together into spheroids, which lie termed "coccospheres."

2 adverbs to describe how to  aggregate  - Adverbs for  aggregate