

A TRIP TO PIPESTONE QUARRY. 653 
in the place of tobacco, grows here. The Reed-grass 
(Phragmites communis) grows in all wet places here, as 
well as throughout the north-west, but it is seldom if ever 
used by the Indians for their pipestems. They commonly use 
a strong piece of young ash wood, from which they punch 
the pith to make the bore. 
The form and size of the pipes made by the Indians re- 
quires so large a piece of stone, that we have no difficulty 
in obtaining all the specimens we desire from the rejected 
pieces strewn upon the ground. Our specimens packed in 
the wagon, and our camp broken up, we start on our return 
to the fort by the tepe trail shown in the diagram. Maza- 
chistina mounts at the same time, but starts off towards the 
Medicine Rocks, around which he makes a rapid turn and 
overtakes us upon the road. He is utterly silent when we 
ask him why he went there, but we should doubtless be 
thankful that we got away with our Pipestone in safety 
from the wrath of the guardian spirits of the Medicine 
rocks. 
But some one asks, “ What is this Pipestone, and what is 
its composition?” It is chemically a clay (silicate of alumina) 
colored brick-red with per-oxide of iron. It is too heavy 
for pipes for white men, and is valued by them almost en- 
tirely for its legendary interest. It is heavier, harder, and 
in every respect inferior to meerschaum,—silicate of mag- 
nesia,—yet the purer specimens may be worked without 
much difficulty with a common saw, file, or knife, and readily 
takes and retains a considerable polish. Geologically it is 
metamorphic clay, as the quartzite is metamorphic sand- 
stone. It was originally a layer of clay intercalated between 
layers of sandstone, and the same metamorphic action that 
changed the latter to a quartzite, also converted the clay into 
Pipestone. 
