APPENDIX. 
SUPPLEMENTARY NOTES TO CHAPTER I. 
The proof sheets of this chapter had long passed through my hands when, through the 
kindness of Mr. Murray, I came into possession of Number IX. of the Reports on the 
Norwegian North Atlantic Expedition, which includes one by Schmelck on a series of 
sea-water analyses executed by him. 
Schmelck examined some 51 waters, and in most of these determined the quantities 
of sulphuric acid, lime, and magnesia. In only six samples he determined also the 
potash. The chlorine he never determined himself, but adopted for it the values which 
had been ascertained on board ship by Torn0e’s method (titration with neutral nitrate of 
silver, using chromate of potash as an indicator, and a gravimetrically analysed sea- 
water as a standard chloride). With 16 of his samples these determinations, it appears, 
had not been executed, so that only the results of the remaining 35 could be referred to 
chlorine = 100. 
The following is an extract from his tabular statements of results : — 
Found per 100 parts of Chlorine. 
Sulphuric Acid, S0 3 . 
Lime, CaO. 
Magnesia, MgO. 
Humber of samples analysed, 
31 
35 
31 
Minimum, .... 
11-136 
2-790 
10-903 
Maximum, .... 
11-643 
3 088 
11-773 
Mean, .... 
11-46 
2-99 
11-40 
My mean numbers, as quoted on ) 
page 138, are, . . . j 
11-576 
3-026 
11-212 
Forchhammer found, 
11-88 
2-93 
11-03 
The quantities of potash in Schmelck’ s memoir are given only in terms of lv 2 0 per 
100 parts by weight of sea- water analysed. I have reduced his numbers to 100 of 
chlorine, and in this form reproduce them in the following statement : — 
Schmelck found in one sample by two analyses 2’440 and 2‘420, mean = 2‘430, parts 
of potash, K a O, per 100 of chlorine.* The other six numbers to be given are based on 
* The chlorine for this sample is not given ; I therefore reduced from the quantities of sulphuric acid given to 
the 11-46 parts of sulphuric acid, which correspond, according to Schmelck, to 100 of chlorine. 
(PHYS. CHEM. CHALL. EXP. PART I. — 1884.) 
A 30 
