172 
MAURICE G. MEHL 
with profit, has been struck. The essential idea is that the well 
is a nonproducer, however, and the nonproduction symbol must 
be utilized. The proper designation for such a condition is 
logically half the symbol for an oil well plus the synbol for a 
nonproducer. 
A dry hole is logically a combination of the symbols for a loca- 
tion and nonproduction. It is true that many other details 
concerning a dry hole are interesting and often important, such, 
for instance, as the presence or absence of a sand, the nature of 
the sand, the presence or absence of water, the adequacy of the 
test, etc. It is very doubtful, however, whether such details 
should be recorded on a development map except in the most 
special cases. As a rule the map is a compilation from many 
sources and not the record of the compiler’s direct observation 
of the drilling. To be of real value, the statement that a certain 
dry hole does not mark an adequate test, reasons for this con- 
clusion are necessary. Apparently a written explanation is more 
desirable than a special symbol for many of the details concern- 
ing a nonproducing well. 
Location” usually means actual drilling or good evidence 
that drilling will be started soon — the erection of a drilling rig, 
for instance. Very often a map is well marked with ^docations” 
which are to be construed as meaning that they will become drill- 
ing locations in the ordinary sense if the drilling well” proves 
profitable, if more stock is sold, or if the fancy of the operator 
does not change; very indefinite locations at best, and usually 
calculated to mislead the uninformed. If it is desirable to dis- 
tinguish between actual drilling locations and prospective tests, 
it is probably well to use a definite symbol for a drilling well 
and portions of the same symbol to designate the varying de- 
grees of probability that drilling will be carried on seriously at 
a later time. 
THE UNI-COLOR SYSTEM 
A great variety of simple symbols is to be had by the use of 
colors and in many cases a multi-color scheme is employed to 
good advantage. In most ^^pin systems” for keeping a record 
