Passage: By the time of the American Civil War, as telegraph traffic increased, the Grove cell's tendency to discharge poisonous nitrogen dioxide (NO2) fumes proved increasingly hazardous to health, and as telegraphs became more complex, the need for constant voltage became critical. The Grove cell was limited in this respect, because as the cell discharged, voltage reduced. Eventually, Grove cells were replaced in use by Daniell cells.

Question: What type of electrochemical cell replaced an early electric primary cell?
Daniell cells