178 E. HURST, H. G. SMITH AND J. READ. 
accompanied. by remarkable changes in the magnitude, and 
even the sense, of the optical rotatory power. The follow- 
ing selection from an extensive series of observations is 
sufficient to indicate the pronounced mutarotation which 
occurs not only in chloroform solution but also when the 
substance is dissolved in other organic solvents:— 
1. J-a-Phellandrene o-nitrite (m.p. 121 —122°): 0°7517 gram 
dissolved in chloroform and made up to 30°0 c.c. at 20°. 
Time [a}p Time [a | 
8 mins. +137°7° 4 hours +81°0° 
14 e6 +136°9 25) —23°5 
og Us +135'1 48 ,, ~24°0 
57 45 41253 194 ~70°0 
OST: +99°8 144 ,, —70°0 
2. l-c-Phellandrene «-nitrite (m.p. 121 — 122°): 0°3762 gram 
dissolved in benzene and made up to 30°0 c.c. at 20°. 
Time [o]> Time [a|> 
5 mins. + 234°4° 23 hours +65°8° 
Pia +232°9 On —42°7 
20m ee +220°9 ABT. 55 —87°3 
NOW. +209°7 338 Nhe -103°3 
Tove +189°0 DOD tose — 103°3 
3. l-c-Phellandrene a-nitrite (m.p. 121 — 122°): 0°5014 gram 
dissolved in acetone and made up to 30°0 c.c. at 20°. 
Time [a]> Time [a]? 
8 mins. +165°3° 21 hours +67°0° 
ees +1641 ree aie 
2) eae +162°7 98~.., —7°0 
6O5r.5 +154°8 Boo een —38°1 
SOUP 3 ' +150°8 DOO Lee. —38°1 
Thus, with all three solvents optical inversion occurred 
with lapse of time. These observations have, therefore, 
an important bearing upon the application of the nitrite 

