8 RECORD OF DEEP-WELL DRILLING FOR 1905. 
Examination and interpretation of samples. — In order to assist 
toward more intelligent drilling, the Survey will also examine the 
samples of such materials as the driller does not recognize or will 
interpret for him the logs of such wells as are represented by complete 
sets of samples. 
PUBLICATIONS. 
In addition to the aid rendered the driller by correspondence, as 
pointed out in the foregoing paragraphs, the Survey is enabled to 
assist the driller or well owner further through its publication of 
well records and other information relating to the occurrence of oil, 
gas, and water. Among the many ways in which reports containing 
such information may be of value, the following, which were pointed 
out in the first report on the sample system, may be repeated. To 
the oil and gas driller they furnish information as to (1) the best 
point for locating the well, (2) the depth of the supposed productive 
bed, (3) the character of the material to be penetrated, (4) the 
amount of water which will be encountered, (5) the amount of casing 
required, and (6) the limit of depth to which it is desirable to drill. 
To the owners of such wells information as to each of the foregoing 
points, especially those affecting the cost of the wells, is furnished 
by the records, in addition to data relating to still more important 
factors — namely, those of quantity and quality of supplies. In the 
case of drillers and owners of water wells the same information is 
furnished, but here the items affecting the cost are of increased impor- 
tance, owing to the lower value of the product, and questions oi 
head, quantity, and quality of supply again come to the fore. To 
prospective owners records show the results obtained by others and 
the probabilities of success of new ventures, while to the geologist 
they are of value in assisting to a more thorough understanding of 
the geology, which, in turn, enables him to answer more intelli- 
gently the numerous questions constantly referred to him by drillers, 
well owners, and others. 
The reports giving information likely to be of interest to drillers 
are of several kinds, full descriptions of which are given on pages 10-14. 
METHOD OF COLLECTING SAMPLES." 
Arrangements for cooperation.— Cooperation with drillers forms the 
basis on which the work of collecting well samples is conducted. 
Problems are continually arising in the field in connection with 
drilling, and information is wanted by the driller as to the geologic 
formations to be encountered, the nature of peculiar materials 
brought up by the sand pump, and ihe probable depth and character 
of supplies. Careful attention is given to such requests, and all 
a For full description of office methods see Bull. U. S. Geol. Survey No. 264, 1905, pp. 27-39. 
