Company Names, addresses, dates:
Ver-Vac, Washington DC
Ver-Vac does not appear in any Washington DC city directories. The patent date on the bottle below is September 1920, so they were probably in Washington DC somewhere near that timeframe.
A thread on antiquebottles.net says that Ver-Vac eventually became Nichol Kola.
book # 699
This is a aqua 7.7" crown top bottle embossed:
front: VER-VAC / REGISTERED / VER-VAC BOTTLING CO. / WASHINGTON, D.C.
back: VER-VAC / REGISTERED / 6 1/2 FL. OZ. / D.O.C. 120-3
base: BOTTLE PAT / SEPT 14, 1920