1914] Sumner, et al.: Physical Conditions in San Francisco Bay 81 
period. Such figures would serve as a useful check upon those for 
river flow, computed in other ways. 
Unfortunately, we have no adequate data of the sort referred to. 
Of the two oceasions when hydrographic observations were conducted 
at hourly intervals throughout a complete tidal eyele, the first gave 
results which are in fairly close agreement with the estimated river 
flow for the same period. The second, on the contrary, showed an 
actually higher mean salinity for the ‘‘ebb’’ phase as a whole than 
for the ‘‘flood’’ phase. Various other anomalies in the results last 
referred to have already been discussed. They show the futility of 
attempting to base any far-reaching conclusions upon single experi- 
ments of this sort. 
In order to ascertain the condition of the water in that part of 
the ocean adjacent to San Francisco Bay, salinity determinations were 
made between October 15 and November 4, 1912, at nine stations out- 
side of the Golden Gate (plate 2). Seven of these (D—5807 and 5806, 
and 5792-5788 inclusive) were made at about equal intervals along a 
line extending from the Golden Gate to a point nearly south of South- 
east Farallon Island. The nearest of this group to the Golden Gate 
(D-5807) was about three and one-half nautical miles from the latter, 
the depth being nine fathoms. The farthest station from shore 
(D-5788) was about twenty-six nautical miles from the Golden Gate, 
at a depth of over sixty fathoms. 
Hydrographic observations were likewise made at two other stations 
(D-5785 and 5787) from sixteen to twenty miles southwest of the 
Golden Gate, at depths of about forty fathoms. 
It was our endeavor at most of these stations to take water samples 
and temperatures at the surface and bottom and at a point about 
midway between the two. Since the messenger which should have 
reversed the lowermost water bottle failed to work in some eases, and 
since no significant stratification was commonly observed as regards 
the salinity, I will present herewith the mean figure for each station. 
The following stations are arranged in sequence, commencing with 
that one nearest to the Golden Gate: 
H-5227 (D-5807) 
H-5226 (D-5806)... 
H-5225 (D-5792)... 
H-5224 (D-5791) 
H-5223 (D-5790)... 
H-5222 (D-5789)... 34.10 
5221 (D=5 7/88) 34.05 
