56 



SCIENCE. 



[N. S. Vol. XV. No. 367. 



the bottom were practicable on the hydro- 

 graphic side. Current investigations, fun- 

 damental in importance as they are, could 

 be prosecuted to but a very limited ex- 

 tent. 



The dredge and trawl were chiefly relied 

 upon in the collecting. For various rea- 

 sons it was found both impracticable and 

 unwise to attempt deep plankton work to 

 any considerable extent ; neither could sur- 

 face plankton collecting be extensively car- 

 ried on, though the limited efforts in this 

 direction were productive of interesting 

 and valuable results. 



Both the hydrographic and the biolog- 

 ical explorations were extended from the 

 shore line to the hundred- fathom curve. 

 The general purposes of the summer's un- 

 dertaking dictated that the explorations 

 should be carried out with as much accu- 

 racy and detail as possible within these 

 bathymetric limits, and that the geo- 

 graphical range over which they should ex- 

 tend should be made secondary to this aim. 

 San Pedro was selected as the base of oper- 

 ations, on account both of its central loca- 

 tion in the area to be siirveyed and its nat- 

 ural advantages as a site for a marine 

 station. The plan was to explore the coast 

 immediately contiguous to this place and 

 then extend the work to the south and 

 north as far as the time would permit. It 

 was hoped before operations began that 

 they might reach to San Diego at the south, 

 Point Conception at the north and vari- 

 ous of the islands off the coast. Experience 

 proved, however, the impossibility of accom- 

 plishing so much. The areas actually cov- 

 ered are about thirty miles of coast in the 

 vicinity of San Pedro, viz., from Redondo 

 pier on the northwest to Newport Bay on 

 the southeast; around Santa Catalina 

 Island ; and the vicinity of San Diego from 

 the Los Coronados Islands on the south to 

 La JoUa on the north. 



The following table, compiled from the 



field records, shows something of the amount 

 and distribution of the summer's work: 



EQUIPMENT. 



Vessel.— The new gasoline launch Elsie, 

 forty feet in length over all, with a 17- 

 horse-power engine, was hired for three 

 months, from May 15 to August 15. The 

 boat proved to be excellently adapted for 

 the purpose, although not built for such 

 service. Contrary to the usual practice in 

 the construction of boats of this type, her 

 entire middle and after portions are with- 

 out cabin, and are consequently available 

 for working space. The hoisting gear was 

 placed in the middle. The after-deck was 

 supplemented by a temporary structure, 

 extending between it and the hoisting 

 winch, to be used for receiving and sorting 

 the contents of the dredge. 



One of the most serious obstacles in the 

 way of successful dredging and trawling 

 ■\vith a vessel propelled by a gasoline engine 

 is always found in reducing the speed of 

 the boat sufSciently to keep the trawl on 

 the bottom during the towing without un- 

 duly weighting the apparatus. The problem 

 was solved in this instance by using a bat- 

 tery instead of the engine's dynamo for 

 exploding the gasoline, and by casting out 

 a sea-anchor under some conditions. 



HOISTING GEAR AND COLLECTING APPARATUS. 



A hand winch was used for handling the 

 collecting apparatus. With this the 

 strength of four men was sufficient for ac- 

 complishing the dredging aims of the ex- 

 pedition, although it was found that a 



