UTAH ACADEMY OF SCIENCES 207 
cerning the physical characteristics of an-ore is in the 
possession of those engaged in conducting testing work 
that they are properly qualified intelligently to diag- 
nose the difficulties which may arise in the actual testing 
operation and when thus equipped they may rest assured 
that in so far as a knowledge of the ore itself is con- 
cerned the work is being conducted in a logical and 
scientific manner. 
During the time spent in microscopic work on ores 
from many widely separated localities the conclusion has 
been reached that except to somewhat limited extent 
too little attention has been given to obtaining detailed 
information concerning the character of the ores under- 
going treatment or that when this information is known 
that it has been acquired only after the expenditure of 
large sums of money and time in the working out of 
innumerable cut and try expedients, much of which might 
have been avoided by applying scientific and logical 
methods from the beginning. 
There are many works (*) published containing 
detailed descriptions of microscopic methods that have 
been used with success in the various sciences and are 
the result of years of careful and painstaking investi- 
gations by men who have devoted their entire energy 
to the field of microscopic research. Many of these 
methods may be applied to the study of ores and minerals 
from an ore dressing standpoint, some of them without 
any change or modifications, while others must be varied 
slightly to conform to the conditions existing in this 
particular field. 
All ores do not present the same problems and in 
consequence many variations and combinations of micro- 
scopic methods may have to be applied during the pre- 
liminary work on any particlar ore. Much of the min- 
eral wealth of the United States is represented by ore 
bodies whose exploitation is beset with difficulties, the 
greater portion of which are encountered in ore dressing 
and concentration. The complex sulphide ores are 
especially typical in this respect. These ores as a rule 
2Manual of Petrographic Methods, Johannsen; Elementary 
Chemical Microscopy, Chamot; The Microscope, Gage. 
