HAworkru. | Ore Deposits. 121 
that the fissures themselves probably reach down to the 
realms of hot water, which in turn means that the total ab- 
sence of hot water minerals at and near the surface cannot 
well be explained. It remains for the advocates of deep fis- 
sures to explain this very notable absence of silicate minerals. 
(b) It would seem to the writer that Professor Van Hise 
has emphasized too much the importance of a shale bed lying 
below the ore bearing formations and another one above. At 
best the lower shale bed is only a few feet in thickness, and 
in many places is entirely wanting. This is shown by the 
records of wells in the oil fields of Kansas near by, and also 
by wells in the mining district itself, as has already been 
pointed out. A shale bed rarely over 12 feet in thickness 
could hardly wield any considerable influence, even though 
it were continuous. but when it is not continuous its influ- 
ence would certainly be ml. Again, it is the most common 
of occurrences throughout the entire stratified rocks of the 
world to have a heavy limestone bed with shale both above 
and below it. Throughout the Coal Measures of Kansas and 
Missouri adjacent to the ore mining region this is a most 
common occurrence. We have Fort Scott limestone immedi- 
ately overlying the Cherokee shales and in turn overlain by 
a shale bed from 30 to 40 feet thick. We have the still 
greater mass of limestone which outcrops within thirty miles 
of the zinc mines, a mass of limestone aggregating about 100 
feet in thickness, with heavy shale beds both above and be- 
low. In fact, such conditions are so common that if to such 
a structural relation is to be ascribed the Galena-Joplin ore 
bodies, then we have a right to expect universal deposits of 
lead ores and zinc ores within limestones similarly situated 
between shale beds, which would mean throughout almost 
all the stratified areas of the world. 
An equally strong objection to the influence of these under- 
lying shales is that it is assumed they are badly fissured and 
therefore will allow water to pass through them. The more 
one emphasizes the extent and depth of the fissures the more 
pronounced this objection becomes. If the fissures are as 
ereat in number and capacity as Van Hise and Bain have 
claimed, and if the ore bodies were formed originally by as- 
