Company Names, addresses, dates:
  Brownie, Washington DC

Notes:
Brownie doesn't show up in any Washington DC city directories. From the markings on the bottle below, it would appear they had some type of bottling operation in Washington DC. There are several blogs references to Brownie on the web.
One says that Brownie Root Beer was one of many beverages bottled by the Atlas Beverage Company of Detroit Michigan¹.
Another one says that Brownie was a Chocolate Drink similar to Yohoo².
I've seen Brownie bottles that were somewhat similar to the one below, that had embossing saying they were bottled by the 7-up Bottling Company³.
A guy named Palmer Cox⁴ is the guy who originally drew brownies like the one embossed on the bottle below.


Bottles:

(enlarge)

This is a 7.7" clear crown top bottle embossed: front: TRADE / BROWNIE / MARK / CONTENTS 6 1/2 FL. OZ. back: TRADE / BROWNIE / MARK / REGISTERED base: WASHINGTON, D.C. PATENTED