46 



Sum 98.60 



Samlede Bestanddéle: 



FeO Fe 2 3 A1 2 3 OaO MgO ,CaC0 3 



2.05 . 2.97 9.58 0.20' 2.9] 0.50 

 Glødn.tab Sum 



5.49 98.60 



P 2 5 

 Spor 



Si0 2 

 74.90 



Bundprøven fra Station 267 har ikke ligesoin den 

 foregaående undergaaet nogen Forandring ved at henligge 

 i Luften; ved to Bestemmelser af dens Jernoxydul- og 

 Jernoxydmængde med længere Tids Mellemrum er jeg kom- 

 met til de samme Resultater. Forholdet mellem Oxyderne 

 var i begge Tilfælde 0.49. At Glodningstabet ved den 

 sidste Bundprøve er betydelig høiere end ved den første, 

 kan maaske være begrundet af en større Rigdom paa or- 

 ganiske StottV. Denne er muligens ogsaa forenet med .en 

 større Stabilitet ligeoverior Luftens Baavirkning (?). Begge 

 Bundprover udviklede ved Ophedning en stærk ammonia- 

 kalsk og empyrevmatisk Lugt. 



Foruden de ovenanførte Analyser har jeg i Rhabdam- 

 mina-Leret udfort en Del Kalk- og Jernbestemmelser, der 

 vil tjene til Oplysning om dets Dyreliv og eiendommelige 

 Oxydationsforhohl. Maengden af den kulsure Kalk er fundet 

 med Johnsons Apparat; Jernoxydul og Jernoxyd bestemt 

 ved Titrering med Kamæleon og undersVovlsyrligt Natron. 



Sum det vil sees. er Kalkgehalten overordentlig ringe 

 paa alle de Stationer, som ligger østenfor Beeren Eiland 

 og' søndenfor denne Ø's Breddegrad. Nogen tilsvarende 

 Fattigdom lindes neppe i Nordhavets øvrige Sedimenter 

 eller er ialfald ikke paa saa store Strækninger udbredt med 

 aogen lignende Etegelmæssighed. Den samme Mangel paa 

 kulsur Kalk har jeg -fundet ved med Saltsyre at forsøge • 

 de øvrige Bundprøver, der er indsamle.de fra denne Egn 

 ai Havbundeu. Overalt viser sig kun en ganske ringe 

 Kiilsviviulvikling. 



Paa Station 326. der ligger i det lille Parti af Rhab- 

 dammina-Leretj som paa Kartet er antegnet mellem Beeren 



. Decomposed 

 by 



Hydrochloric acid 

 9.83 pCt. 



Undecomposed 



bj 



Hydrochloric aeid 



83.28 pCt. 



Loss by ignition . 5.49 



Protoxide of irpn . 2.05 



Sesquioxide of iron 1.00 



Alumina . • . . . 0.25 



Lime 0.20 ' 



Magnesia .... 1.49 



Carbonaté of lime. 0.50 

 Phosphoric acid • Traces 



Silica 4.34 



Sesquioxide of iron 1.97 



Alumina .... 9.33 



Magnesia . . . . 1.42 



Silica . . . ' . . 70.56 



98.60 



Constituents of Sample: — 

 FeO Fe,0 3 AL.O., CaO MgO 

 2.05 2.97 9.58 0.20 2.91 

 Loss by Ignition 



CaC0 3 



0.50 



P 2 5 SiO a 



Traces 74.90 



5.49 



= 98.60 



Unlike the foregoing. the sample from Station 267 

 did not uudergo any visible or substantial change on being 

 exposed to the air. " Two determinations of the protoxide 

 and sesquioxide of iron. peribrmed with a considerable 

 interval between, gave the same results. The ratio of the 

 oxides was in each case 0.49. That the loss by ignition on 

 determining the constituents of the latter sample should 

 have been considerably in excess of that resulting from the 

 analysis of the former, from Station 264. may perhaps be 

 ascribed to a greater abundance of organic remains. which 

 in turn will possibly account for the greater stability ex- 

 hibited in withstanding the influence-of atmospheric air (?). 

 Both samples emitted on exposure to heat a strong amino- 

 niacal and empryeumatic odour. 



Exclusive of the above-mentioned analyses, . I have 

 peribrmed in Rhabdammina clay divers determinations of 

 Hine and iron. which will serve to throw light on the orga- 

 nisms present in that deposit and the characteristic results 

 of its oxidation. The amount of carbonaté of lime was 

 found with Johnson's apparatus, that of protoxide and ses- 

 quioxide of iron by titration with permanganate- of man- 

 gan ese and hyposultite of soda. 



As will be seen from the Tahle. the proportion of 

 lime was remarkably small in' all the samples collected at 

 Stations east aud south of Beeren Eiland. A corresponding 

 characteristic as regards this constituent will hardlv be 

 found to occur in any other of the North-Atlantic deposits. 

 at least with equal uniformity throughout such extensive 

 tracts. The same comparative absence of carbonaté of lime 

 1 have determined, by treating with hydrochloric aeid. in 

 the remaining samples brought up from that tract of the 

 ocean-bed. The quantity of carbonie acid thus geiierated 

 w. -is without exception \^yy trifling. 



At Station 326. located between . Beeren Eiland and 

 • Spitzbergen, above the small section of the sea-bed shown 



