34 



Forsogene ere nemlig ikke blevne udførte paa Vandprø- 

 verne strax elter . deres' Optagelse men forst, etterat de 

 have henstaaet i kortere eller hengere Tid. Angaaende 

 Tidsrammet, hvori de enkelte Vandprøver have henstaaet 

 før Bestemmelsen, kan anføres Følgende': No. 1, en Yand- 

 prove. som Hr. Dampskibsfører E. Rostrnp viste mig den 

 VelviUié at skatte mig, har kun henstaaet nogle Tage. de 

 øvrige Prøver have henstaaet, No. 2—6 i ca. 2 l l± Aar, 

 7—37 i ca. I 1 ., Aar og 38—78 i 2 til 4 Maaneder paa 

 et kjøligt Sted opbevarede paa Flasker, der vare forsynede 

 med vel islebne Glasproppe. Der aabner sigtaltsaa en 

 'Mulighed for, at der ved Oxydation af de i Søvandet va- 

 rende, aldrig manglende, organiske Bestanddele kunde have' 

 dannet sig en mindre Qvantitet Kulsyre paa Bekostning af 

 ■den oploste Surstofmængde, en Proces, der naturligvis kun 

 har Indflydelse paa den surt bundne Kulsyre, saafremt 

 ikke Oxydationen skulde skride saa vidt. frem, at bgsaa 

 Surstoffet i Svovlsyren skulde medgaa til Dannelsen af 

 Kulsyre. i hvilket Fald den dannede Kulsyre lnaatte træde 

 ind som neutralbunden istedetfor den destruerede M.engde 

 Svpvlsyre. En saa vidt fremskreden Oxydation kan imid- 

 lertid ikke benkes mulig, inediniiidre man til Prop i Fla- 

 skerne anvender Kork, da den i Sovandet opløste Surstof- 

 gas er mere end tilstrækkelig til at oxydere alle de op- 

 rindelig tilstedeværende organiske Bestanddele. Det kau 

 ogsaa bemærkes, at det ikke i nogen af de undersøgte 

 \"andprover har været muljigt at paavise det miiulste Spor 

 af Syovlvandstof. For saa aogenlunde at fixere de Mæng- 

 ilrr Kulsyre. -som paa denne Maade skulde kunne dannes. 

 har jeg anmodet min Ven Schmelck, sum har været beskjæf- 

 tigel med Dnders/zfgelse af de laste Bestanddele i Våndet i 

 det af Expeditionen befaxede Eav, oa som saaledes ogsaa biar 



having all of it been 'allowed to stand over for a longer 

 br shorter period. With respect to the interval that bad 

 elapsed befqre commencing the determinations. the follow- 

 ing particulars can be given: — No. 1. a sample of sea- 

 water which Captain E. Rostrup bad the kindness to prooure 

 me, did not stand over for more than a few days: of 

 the remaining samples. Nos. 2—6 were preserved for about" 

 two years and a quarter. Nos. 7 — 37 for about one year 

 and a. quarter, and Nos.- 38 — 78 from two to four months. 

 all of them in a cool spot, and in bottles lurnished with 

 ground glass stoppers. Hence it is just possible that 

 oxidation of the organic matter never absent in sea- 

 water may have produced a small quantity of carbonic 

 acid. by reduoing the amount of oxygen. a process which 

 of course could onlv affect the carbonic acid forming bi- 

 carbonates. unless indeed oxidation were so far advanced. 



. that the oxygen in the sulphuric acid should also coutri- 

 bute to the formation pf carbonic acid. in which case such 

 carbonic acid would reimplace the sulphuric acid decom- 

 posed. But tltis advanced stane of oxidation is clearly im- 

 possible unless the bottles are corked, since the oxygen 

 in sea-water is more than sufficient to oxidize all organic 

 matter originally present. I can also observe. that in none 

 of the samples of water examined was it possible to detect 



, the slightest trace- of sulphuretted hydrogen. 'With the object 

 of determining approximately what proportion of carbonic 

 acid could result from this process, I requested my friend 

 Mr. Schmelck -- whose labours have been chiefty contined 

 to the examination ■ of the solid matter present in the water 

 of the sens exphnvd on the Expedition. and who accord- 

 ingly instituted a seines of experinients to ascertain the 

 amount of organic substances it contained — to furnish 



