On the Use of the Hydrometer of Total Immersion. 



Jakob Schetelig. 



J_Juring the course of the past winter, as Professor FrnDTJot 

 Nansen's assistant, I have made a great number of determina- 

 tions of the specific gravity of sea-w^ater with the professor's 

 hydrometers of total immersion. All the water-samples of 500 

 cub. cm. in soda-water bottles, from the cruise of the "Michael 

 Sars" in the summer of 1900, have been determined by me 

 according to this method, as also a series of samples collected 

 by Mr. Alf Wollebæk during the "Heimdal's" cruise in the 

 Arctic Ocean in the spring of 1900. 



As several inquiries have been addressed to Prof. Nansen 

 as to the best mode of procedure in the practical use of the 

 hydrometer of total immersion, the professor has requested me 

 to describe the method employed in the determinations made by 

 me, and to relate my experience as to the quickest and mos 

 convenient way of obtaining accurate results. 



Professor Nansen has described this method, and proved 

 its advantages theoretically.^ The method is briefly the follow- 



* Fridtjof Nansen, The Norwegian North Polar Expedition, 1893—1896 

 Scientific Results. Vol. UI, No. X, pp. 83—87. 



