) 05 ce. cthyketone sowed in 4.0 cc; "benzoate solution. H,O can be © 
Bikar 11. 20. ce. < ibdiayt Neatiok dissolved in 05 Cc. henge solution. 05' ceo} 
_ caused ‘cloudiness; 0.5 ce benzoate Solution cleared this” een and then 0.5 cc. more 
: HO was tolerated. — ketene i 
12.1. 0 ce. phenylethyl aleohol gave. a clear salon with 0.5 cc. benzoate solution. © 
02 co. HO. were tolerated, 0.5 cc. H,O- caused cloudiness. 
43, 2.0 cc. cinnamic sleohol (liquefied) gave a clear solution with 1.0 cc. benzoate 
Fearon. 0.5 ce. HO caused pleadines) addition of 1.0 cc. benzoate solution cleared 
- the ‘mixture asain on 6s Ee 
RF “cloudiness. More water precipitated oil. 
Bs - 15. 1.0 cc. cyclohexane (Kahlbaum) gave a clear solution inet Ovee: benzoate 
ae solution. The solution tolerated 1.0 cc. H2O. } 
2 
x ; 
An Gateeation by H. Zeehuisen treats of the Union by spraying ( Ver- 
__stizubung) of perfumes, and of intensity*) of odour. Only substances that are to some 
- showed that in homologous series, odour and charge are parallel properties. The 
~ limits” of perceptibility of odour and of charge are in general the same. Probably 
’ both: intensity of odour, and electric charge depend on the volatility of the substance, 
as hele as on ‘the lowering of the surface- tension of water which it brings about. 
S Semae (grey wedge photometer) is described by W. Hecht?). The process is 
“ an improvement of the “Skalenphotometer” (scale photometer) introduced by Kissling*). 
‘The ‘paper Scale, rising in steps, is replaced by a continuous neutral grey wedge, thus 
3 increasing” the possible time of exposure to light and lessening the limits of error. 
‘Hecht gives in his work an historical survey of the usual methods of light measure- 
3 ‘ment hitherto used in botany. Whilst the “Normalfarbenphotometer” (normal colour 
a photometer) is best for absolute measurements, the “Graukeilphotometer” best meets 
% the demands for comparative light measurements, since measurements can be made 
xe simultaneously at a number of points, and for various times of exposure. The “Grau- 
: _keilphotometer” deserves this much notice, since light measurements are of great 
+ _ importance in all Benertmenits of science, arts, and industry, and especialy in plant 
é cultivation. Sars | 
a ~ 
_ shown that in ‘homologous series the characteristic wave lengths remain approximately 
constant. If they are displaced by more than 10—15 “w by insertion of a group or by 
4 researches have shown that the phenomena of anomalous dispersion can be traced to 
the increase of negative groups, and to the disturbing influence of multiple bonds, in 
“a which case the proximity of certain groups has an important influence. The normal 
Ko 
—_*°__ For liquid 
ae a 
- rotation dispersion of organic substances is calculated from a, = 
gi 2 Koninkl. Akad. van Wetensch. ee Wisse en Natk. . Afi 28 (1919), 11. As per Chem. Zentralbl. 
4 1920, I. 234, Cf. Reports 1917, 114; 1918, 95. -- *) Sitzwngsber. d. akad. Wiss. in Wien. Math -naturw. Klasse 
Abt. Ha, 127 (1918), No. 10. — 4) Katong, Einfluss der Chemischen Lichtintensitit auf die Vegetation. 1895. — 
yy CE. Report 1918, 96. ; 
- | 
ri _ extent soluble in water take up a charge. 24 different perfumes, chosen arbitrarily, 
a ; Corniadion shel pia rotatory power of catieallah active b ebstaners: — H. Rupe*) has 
ey sys 
"4 ‘he's 
4 OG 
BS 44, 2.0 cc. eugenol were . dissolved in 2.0 cc. benzoate solution. 0.5 CC: H,0 caused ~ 
2A new Fichhad for the continuous measurement ‘of light oie with the. cate | 
change in the linkings, we suspect relative or total anomalous dispersion. Previous | 
