I got the 1893 map to come up but not the one from 1906.
It looks like the Washington & Jackson Sts. line did proceed beyond Steiner for a time, but that would have made for a long rope. And subsequently the line terminated at Steiner and AFAIK any other trackage removed. The Cal cable went to Presidio but that rope came out of Hyde St. not Mason St.
So they would have wanted to put Sacramento St. cars into service as close to the carhouse as possible. Jack Woods would have had to deal with this issue in 1954 with the massive cutback of the cable cars. How to put the Cal cable cars into service out of Washington & Mason carhouse? I assume they looked at the famous intersection of Powell and California Sts. But grades on all sides and very steep on two sides. So they made a connection at California & Hyde with the one rope making a detour up Hyde to Washington & Jackson Sts. The United Railroads could not do anything like that since Hyde St. trackage belonged to the Cal Cable RR Co.
Interestingly the quite long length of the current Cal Cable rope may have been a tacit reason the line was cut back to Van Ness when Fillmore would have been a better terminus(it was the terminus originally). Of course DPW would have totally opposed but the need for a second rope, as with the Sacramento St. line, would have upped the operating costs along with having to rebuild the slot west of Van Ness.
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