What was Hall fetching for his wife in Chapter 6?

Mr. and Mrs. Hall were doctoring the beer in the cellar. She sent her husband back upstairs to fetch the sarsaparilla.

They had hardly entered the cellar when Mrs. Hall found she had forgotten to bring down a bottle of sarsaparilla from their joint-room. As she was the expert and principal operator in this affair, Hall very properly went upstairs for it.