1896 | TOXIC ACTION OF DISSOLVED SALTS 97 
16. 1CuSO, + 1C, -H,,0O,, +:3K08, 
200 cc. CuSO,4, s$y gm. mol. per liter; 200 cc. sugar, y}y gm. mol. per liter; 
3 cc. normal KOH. (Begun December 5, 8 P.M.) 
ntration 
Conce Length Length 
gm. mol. per liter | Dec.6,9A.m. | Dec, 9,9 A.M. Remarks 
xoo 15.0" o2008 living 
ee 19.0 “ 21:05" Me 
(Slight precipitate, probably due to contact with air and CO, excreted from roots. 
Concentration given based on CuSO, content.) 
17. 1CuSO, + 1C,,H,,0,, + Ca(OH),. 
200 cc. CuSO,4, $y) gm. mol. per liter; 400 cc. sugar, ;49 gm. mol. per liter; 
106.4 cc. Ca(OH), (saturated solution). 
(Begun December 5, 8 P.M.) 
Concentration Length Length 
gm, mol. per liter. | Dec. ap A.M. | Dec, ste A.M. Remarks 
0.00142 19.5™™ 46.0™™ alive 
19.5 “ 8.5 “ . 
: (Solution deep blue. A slight precipitate formed on standing. Concentration 
Siven based on CuSO, content.) 
It has been shown” recently that in Fehling’s solution and 
allied solutions containing copper the copper does not exist as 
an ion by itself, but as a part of a complex ion formed with the 
rganic substance present. Such complex ions, according to our 
theory, we should naturally expect to have a quite different toxic 
action from that shown by copper ions. Experiment has verified 
this. In tables 16 and 17 are given the results obtained with 
Solutions of the character just mentioned. The composition of 
the solution is indicated in each table. Cane sugar was used 
instead of Rochelle salts in order to avoid getting too many salts 
Pd ha solution. An excess of caustic alkali was also avoided 
Da It would have introduced hydroxyl ions into the solution 
which are of themselves poisonous. The beans grow in this 
17 : 
Kahlenberg, Zeitschr. f. physik. Chem. 8: 587, 608-613. 
