128 Ih*' Ainei'tcdii (iiohxji.sf. 
Febriijirv, 18!ty • 
l^et US consider tlie pref^eiit !>ituati<)ii for a nioiuent. Our country 
is to-day almost the only civilized nation which has no good map of 
its area, and scientific and industrial interests are suffering daily for 
lack of such a map. Every year that can be saved, in its comi)letion. 
will save millions to our industries. Time and expense as well as 
(|uality should tlierefore be considered. 
The work is to-day, in law and in fact, in the hands of the (ieologicai 
Survey, is being executed rapidly, etficiently and economically. ^lore 
tiian one-filth of the area of the country, excluding Alaska, has been 
mapped and those who use the maps agree witli you that they are 
useful and good. The Geological Survey lias a large corps of well 
trained topographers, and is fully e(|ui|>ped for carrying on the work 
to completion. 
All this is certainly favorable to maintaining the status (juo. 
Xow will the (juality be improved, the time shortened or the ex- 
pense lessened by the transfer? And if by transfer, the (juality could 
be improved, will such improvement comiiensate for the added time 
and exi)ense attendant upon it? 
These are matters about which ditl'erent o])inions may be held, but 
in considering them let it be steadily remembered that the present 
status is producing, on the whole. satisfactory results, while the results 
of a change are uncertain. !ii:\i;v (iwM-nT. 
Washnii/tn,,, Jan. li;, IS'J.J. 
Mi;. Tapf's liKi'LY TO 1'rok. llii.L. I'emiit me to correct some 
erroneous statements in the criticism of my report in your ])ecember 
number. On page No. 39i ^Ir. Hill says: •"Concerning the age of the 
Trinity beds of my Trinity division for which ^Ir. Tatf. without state- 
ment of authority or reason, substitutes tlie name Uosque." This 
statement is undoubtedly the result of an oversight or misconception 
on the part of the critic. I wish to say i)lainly that I did not api)ly 
the name "Rosque" to the Trinity beds as defined by Mr. Hill, more- 
over, I gave clear reasons why the Trinity and (tIcii Rose beds, his 
Trinity division, are inseparable ])arts of a tripartite division.- A\'hy 
I did not apply the name Trinity to this clearly deiined division is 
evident. The name Trinity division was given first to tlx' Trinity 
sand bed l)y Mr. IIill.+ Later this Trinity division was thrown with 
the Glen Kose limestone for the reason tiiat"! have discovered," he 
says, "that the beds described under this general term (Trinity or 
Basal division ) really include two stratigraphic subdivisions separ- 
ated by distinct lithologic and jtaleontologic characteristics.''^ a 
peculiar reason why two beds should Ite classed under a single divi- 
sion. To augment further the confusion by applying the name Trinity 
to my new tripartite division when one of those subdivisions had been 
properly named "Trinity" would be altogether unreasonable. The 
rocks of the Bosque division are most beautifully developed and ex- 
*Geol Survey of Texas, Third Animal Report, IS'd, i)p. Nos. 300, 306, 3(iT, 311, 312, 3'.>3. 
and 3-24. See also details of sections of the Bosihh' division. 
+Geol. Snrvev of Arkansas, 18S8, Vol. ir, p. IKi.et sei).. (ieol. Siirvev of Texas, Bulle- 
tin No. 4, 18Sy, p. XV, and First .\nnual Report. 18S9, p. No. 118. 
JTlie Comanche Series of the Texas-Arkansas Reu-ion, Bulletin (Jeol. Society of 
America, p. r>{>b. 
