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zeal, efficiency and the accuracy with which his observations and computations have been made.

Mr. Ellsworth proved himself invaluable in varied services as confidential assistant, and I take pleasure in bearing testimony to his energy and faithfulness in the performance of many difficult tasks. After my departure he was entrusted with important work, the performance of which has clearly proven his unusual skill as a collector and his ability to manage well in the field. In the office he did excellent work in arranging and labeling collections and in testing rocks, ores, etc., under my direction.

The other members of the party bore unflinchingly hardships of no small moment, and those who continued to the end proved in every way faithful to their trusts, contributing in large degree to the successful accomplishment of the survey in hand.

Your own constant aid and encouragement, as in other seasons, enabled us to overcome numerous obstacles and made possible much that could not have otherwise been undertaken.

Very respectfully,

Theo. B. Comstock,
Geologist for Central Texas.

REPORT OF MR. W. F. CUMMINS.

AUSTIN TEXAS, November 15, 1891
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Prof. E. T. Dumble, State Geologist:

DEAR SIR—The work done by myself and party during the last seasons' field work was to trace the Carboniferous formation to its farthest outcrop in Central Texas, and to determine the northern extension of the Cretaceous strata along the eastern escarpment of the Staked Plains, as well as to trace and determine the extent of the Dockum and Blanco Canyon beds and their relation to the underlying strata.

A very important question for the northwestern part of the State was to determine whether or not artesian water could be obtained on the Staked Plains. It was already known that the upper strata of the Plains had a general dip from the northwest to the southeast, and it was thought that there might be an underlying strata, whose upturned edge at the base of the mountain range west of the Plains, would furnish a water-bearing stratum that could be penetrated by deep boring farther to the eastward in the country east of the Pecos river. In order to determine this matter, we traveled entirely around the Staked Plains in Texas and New Mexico, and as nearly as could be done during our hasty march, determined the geological age of the strata between the