278 The American Geologist. April, i893 
determine the motion between the two central flags. The pinnacles 
themselves change in shape and appearance from day to day with con- 
siderable rapidity. Especially is this true during rains, which are often 
of several days duration. It is believed that they do not furnish a reli- 
able basis of measurement. 
The writer holds that the sets of measurements made by professors 
Wright and Eeid are completely discordant, and cannot be made any- 
thing else, and that all efforts to show that both may be correct are 
futile. Should there be any doubt as to which set comes nearest the 
truth, the final decision must rest with the party which shall measure 
the motion of Muir glacier for the third time. 
Cleveland, 0., Feb. 27, '93. H. P. Gushing. 
The Artesian and Undekfloav Investigation.— The book re- 
viewed (sic) at page 113 of this volume of the American Geologist, 
is Part III, of Senate Executive Document No. 41, of the 1st Session of 
the 52d Congress, which contains the reports of the geologists of "The 
Artesian and Underflow Investigation," recently made under the 
direction of the Secretary of Agriculture, on the title page of which 
my name appears as Chief Geologist. There are in that part of the 
volume which is properly my own, mistakes of a kind that ordinarily 
make one gnash one's teeth with vexation on their discovery. The dis- 
covery of these came to me at a time when supreme calamity had made 
me indiiferent, and the annoyance is now that such errors (which any 
man competent to discover them could trace to their source and correct 
them), are made a stalking horse in the respectable pages of the Geol- 
ogist. It seems that the words Canon Blanco appear where Palo Duro 
should stand. I had no chance to make a list of errata. In a table of 
geologic formations, "Tertiary" does not appear to be included in 
"Cenozoic," nor "Trinity" in "Cretaceous." The removal of a few of 
the words by the space of two or three ems would place the matter right, 
and any geologist can see it. I saw proof under very adverse circum- 
stances, but did not see the corrections inserted. On such errors the 
strongest criticisms of the reviewer are made. A misstatement is also 
made as to the relation of the Brazos river to the Mississippi. Two 
other rivers are similarly affected by the passage as it stands. The 
insertion of a single word in one of the sentences referred to would cor- 
rect the error. I can't prove the word was in the original copy, but any 
reasonable man with no bad motive would see that its absence was a, 
mere slip. The writer of such a review of course never makes any slips; 
will he give, therefore, an honest reason why he substituted underground 
for undcrflmo in quoting the title of the book he had in hand? 
I have said the Palo Duro canon is a thousand feet deep. This would- 
be critic says it is nine hundred. I used a good barometer, between half 
past nine and five o'clock, on a quiet day, and returned to the starting 
point, and the difference of the "out" and "home" trips was less than 
fifty feet. 
My critic says elsewhere: — "Opposite page 37 he gives Section XX, 
