wells, and after it has absorbed the salt, it is forced up and 
sent on to the Solvay Process Company. As this brine is 
much stronger than that pumped up near Onondaga Lake, 
it is probable that it will soon supplant that article alto- 
gether in the manufacture of salt. 
Still another interesting deposit found in this group is 
a peculiar calcareous rock called magnesian, or vermicular 
limestone. Itis perforated with a large number of cavi- 
ties, somewhat resembling worm borings. It is calcareous 
in composition, and resembles porous tufa more than any- 
thing else. The pores are circular and somewhat irregu- 
lar cavities, often communicating with each other; they 
extend in almost every direction throughout its mass. 
The intervening rock is quite solid. The cavities vary 
in size from those whose diameter is almost infinitesimal 
to those which are over a quarter of an inch in diame- 
ter. Although the rock resembles lava quite closely, 
and at first one might almost conclude it to be such, 
nevertheless a little study will clearly prove its mineral 
origin. The cells are no doubt due to the simultane- 
ous forming of the rock and of some soluble mineral, pro- 
bably a magnesian salt, which was afterwards washed out, 
leaving the rock in its present porous condition. There 
are two masses of this rock, the lower being about twenty 
feet thick. It is interesting to note that where this mass 
is found near James street hill, Syracuse, it contains some 
rocks of a crystalline character, which are serpentines. 
Serpentine is one of the compounds of magnesia, and since 
it is found in the vermicular limestone, it would seem more 
probable that the cavities were formed in the manner sug- 
gested. The upper mass of this limestone is much thin- 
ner than the lower, often dwindling down to a few feet in 
thickness. 
Vanuxem was one of the first to show that in the Salina 
Period, as a whole, we have the same deposits as are found 
17 
