Helser & Unden Machine Works
Helser & Unden were in business as machinists for years before they started manufacturing fire hydrants. Their first attempt at a hydrant contract from the city (bids opened January 1913) was successful, and Helser & Unden hydrants were installed starting in March or April. Little else is known about the company during this period. By the 1920's the company had been renamed Helser Machine Works. Portland made just one purchase of 350 hydrants from Helser & Unden in 1913. Thus, all Helser & Unden hydrants were manufactured in 1913. Many of these are still in service today.
Source: Portland City Directory.
Source: FireHydrant.org
Sources
Last updated February 21, 2018.