Editorial Comment. 257 
equally distributed through the chromatic scale, but to use those that 
may be most readily recognized. 
Mr. H. M. Cadell asked why black and gray were not used. 
Major Powell replied that blue was used in place of the dark shades 
for the Carboniferous ; that dark colors are misleading in regard to the 
occurrence of coal, which occurs in tlie Cretaceous and Tertiary as well 
as in the Carboniferous. 
Mr. Christie found the black color very inconvenient because it oftea 
made the details of the map covered by such colors illegible. 
Mr. H. M. Cadell said that the maps of the Geological Survey of Great 
Britain were colored by hand, and that the system used by the U. S. 
Geological Survey could not for this reason be economically employed. 
Major Powell explained that the U. S. Survey system is very econom- 
ical when the color patterns are transferred to stones. 
Prof. T. McK. Hughes thought it very difficult to devise a scheme that 
will meet the demands of ever3rone. Some reference must be had to the 
permanence of the colors, the readiness with which they can be applied^ 
and the distinctness with which they show what is desired. He thinks 
the fittest scheme must survive. 
Mr. S. F. Emmons made announcements. 
On motion of major Powell, the program for the afternoon was 
changed so that the geology of the country to be traversed by the long 
excursion might be briefly described by those the most familiar with it- 
Adjourned till 2:80 P. M. 
On re-assembling at 2:30 P. M., Prof. Le Conte in the chair, brief 
lectures were given by Prof. Chamberlin, Mi\ Gilbert, major Powell, and 
Mr. Emmons upon the geology of the country to be traversed by the long- 
excursion. 
Adjourned at 4:40 P. M. 
As may be seen from the foregoing, the Congress was occupied 
with the problems proposed for discussion b}' the Committee of 
Organization, as was announced in the Geologist (Vol. viii, p. 
62 ), but there was an apparent lack of orderh' preparation and 
of consistent succession in the proceedings from day to day. 
For instance, the topic which was expected, according to the pro- 
gram announced b}- the Committee of Organization, to come htat, 
was called up t\\Gjii-st tiling f lie first iluy^ and parties who might 
have wished to participate in the discussion were thereb}' pre- 
vented, or were oljliged to ott'er their facts undigested and per- 
haps unarranged, or without the graphic illustrations which they 
otherwise would have employed. It was quite evident, also, that 
some of the gentlemen who led in the discussion of the daily 
topics were compelled to do so on too short notice. It might be 
well for future Committees of Organization to assume more 
