Bartow—A Mechanical Cause of Homogeneity of Crystals. 659 
The above corresponds extremely well with the facts concerning 
a series of isomorphous mixtures of the chlorates of potassium and 
thallium completely investigated by Bakhuis Roozeboom.? 
Both these substances crystallize in the monosymmetric system, 
possess similar crystalline forms, and give rise to isomorphous 
mixtures, not however in all proportions. The following table 
gives the experimental results :— 
ONE LITRE OF SOLUTION CONTAINS 
38 Cae Miligram Ce ee 
F' | TIclo, | KCl0s wae ee eae 
1 | 25-637 = | eae =| spa 0 0 
2 | 19:637 | 6-884 | 68-27 | 56:15 | 194-42 | 45:13 | 9-00 
3 | 12-001 | 26-100 | 41-73 | 212-89 | 254-62 | 83-61 | 19-61 
4 | 9-036 | 40-064 | 31-42 | 326-79 | 358-21 | 91-23 | 25-01 
5 | 7-885 | 46497 | 27-42 | 379-26 | 406-68 | 93-26)) 36-30 and 
6 | 7-935 | 46-535 | 27-60 | 379:57 | 407-17 a 97°93 
7 | 6706 | 46-410 | 23°32 | 378-55 | 401-87 | 94-20 99-28 
8 | 6-723 | 47-109 | 23°37 | 384-25 | 407-62 | 94-27 99-60 
9 | 4-858 | 47-312 | 16-89 | 385-91 | 402-80 | 95-81 99-62 
10 | 2-769 | 47-134 | 9-63 | 384-46 | 394-09 | 97-56 99°67 
11 a Ty Aa-995 — | 407-22 | 407-22 | 100-00 100-00 
Experiments 1 and 11 were made with solutions of the pure 
salts. The mixtures deposited in experiments 7-10 were scale- 
shaped crystals similar in appearance to those of potassium chlorate ; 
experiments 2-4 yielded much smaller, acicular crystals resembling 
those of thallium chlorate. Both kinds of crystals were obtained 
side by side in experiment 5 ; after removing them, and allowing the 
1 Zeitschr. fiir physik. Chemie, vol. viii., p. 531. Compare also, for other cases 
in which two kinds of mixed crystals are deposited by a mixed solution, Rammelsberg’s 
observations published in Poggendorf’s Annalen XCI., p. 321; and also Retger’s 
observations in Zeitschr. f. physik. Chem., vol. ili., p. 542. 
