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bulletin of the bureau of FISHERIES. 
SUMMARY OF CONCLUSIONS. 
Remembering that this experiment is preliminary and that the observations are 
entirely too few to make the deductions conclusive beyond question, still the following 
tentative answers may be given to the questions announced in the beginning of this 
paper. 
1. Salmon may take from 30 to 40 days to pass through the brackish water within 
the limits of the fishing waters at the mouth of the Columbia River. 
2. That salmon spend considerable time swimming back and forth in tide water 
during the acclimatization to fresh water is indicated (a) by the fact that two fishes 
were taken below the point at which they were marked, ( b ) by the corrosion of the 
aluminum marking buttons by salt water, and (c) by the long time spent by certain 
fishes in reaching the lower limits of fresh water. 
3. When wholly within fresh water, the silver salmon and the steelhead make the 
migratory journey at an average speed of from 6 to 7^2 miles a day and probably more. 
4. There is little evidence that the process of marking or that the partial obstruction 
of the course by fishing gear does more than produce a temporary checking of the 
migratory journey. 
