A, Winchell on Drift in Michigan. 331 
much more readily, and the greater the quantity of acid the less 
stable are the 
Crystals of protonitrate of iron, well drained and dried at s 
very low temperature, were found to yield by ignition 27-565 
of ferricoxyd. The formula must therefore be FeO, NO,, 6 0, 
which would correspond to 27-778 p.c. of peroxyd. 
A solution saturated at 0° C., yielded a quantity of peroxyd 
equivalent to 66:3 p. c. of te erystals. So at 0° the salt is pat 
le in half its weight of wa 
A ihe saturated at 15 °C, contained 71 p.c. of crystals. 
Its sp. gr. was 1° 
A pardtiea saturated at 25° C., contained 75 p.c. of crystals. 
Its sp. gr. was 150. At 25°C., then the crystals are soluble in 
one-third their weight of water. 
The slight difference in strength between cold and warm solu- 
tions, as ell as the instability of the solid salt, shows the inex- 
pediciency of attempting to do anything with it except in the 
coldest weather. 
ArT. XXXIV.— Some sbi sig puted a Northward Transportation 
of Drift Materials in the Lower vider of Michigan; by 
Professor ALEXANDER WINCHEL 
THROUGHOUT the northern part of Lenawee and Hillsdale 
“fonnties, the southern and eastern parts of Jackson, and the 
southern and western parts of Washtenaw county, are found 
| Poesious aber, detached masses of limestone, sometimes crop- 
‘ping out on a hill side, like a ledge in place, and sometimes im- 
Med two or three feet in the sand and atten at the summit. 
The position of these masses is generally nearly horizontal, 
though for the greater part slightly gine in = direction or an- 
other. They sometimes present an extent of six, eight, or 
7 : 
