for light also. Such supplies, amounting to a few hundred feet per day, have been maintained for many years. It is scarcely to be doubted that supplies of this character are available in some parts of Ohio. In fact, the amounts that certain wells are known to have produced would be equal to the demands that would be made upon them in household use. It is well to bear in mind that the conditions for the production of gas supplies of this sort are widespread and in constant operation. Το find inflammable gas in small or moderate quantity in the drift is not a ground of surprise. It is an everyday and common-place occurrence. It is also to be remembered that the discovery of such supplies gives no true indication whatever of the presence of rock gas in the underlying strata. Cases will presently be named in which gas in the drift may be referred to the underlying rocks, but so far as supplies that are known to be connected in origin with the great bodies of buried wood that the drift formations contain, no warrant is given by them to expect any gas whatever from the rocky series on which these drift-beds rest. This drift gas originates at a greater or less remove from the rocks, and generally has no connection with them. In the subsequent section there will be discussed another sort of drift gas. THE DRIFT AS A RESERVIOR OF GAS AND OIL. Under this head certain accumulations of oil and gas that are occasionally found in the drift will be described. At first sight all of these occurrences of gas might seem alike, but a little examination suffices to show a broad line of distinction between them. In the case now considered, porous beds of drift directly overlie gas-bearing or oil-bearing rocks, and during the long periods in which they have maintained this relation they have, when suitable conditions of level have been found, been charged with gas or oil. The Mecca oil-field gives an example of this sort of accumulation. As stated on page 330, the bowlder clay overlying the Berea grit at this point has become saturated with oil. Another case of the occurrence of oil from the bowlder clay has recently been reported from southern Ohio. Cases of oil accumulation are, however, comparatively rare. It is of somewhat more frequent occurrence that beds of gravel resting on the Ohio shale, or other gas-producing stratum, become charged with highpressure gas. The most interesting cases that have been noted under this head are recorded on page 349. At Wellington, Lorain county, at a depth of forty feet from the surface, the interval being filled with bowlder clay, a bed of sand and gravel was found, heavily charged with gas, which is obviously derived from the Black Berea shale on which the porous beds rest. The gas, when its reservoir was tapped, escaped with great violence. Hon. R. A. Horr, whose residence is near this well, was encouraged by this experience to drive a pipe on his own premises to the sand bed. He was rewarded by a flow of gas which has supplied his house with heat and light for the last six months, and which shows thus far no perceptible abatement. A similar case is reported from Cleveland on page 430. It will also be remembered that the drift beds at Findlay were directly connected with the surface indications that the people there so long and persistently refused to recognize in their true significance. In penetrating them gas was almost always obtained in considerable abundance. The two distinct sources of gas in the drift have now been pointed out, and, in view of the facts already presented, its frequent occurrence is seen to be no ground of surprise. Its geological significance is also easily apprehended. As a rule, it has no bearing on the question of rock supplies. THE THICKNESS OF THE DRIFT DEPOSITS IN OHIO. Under the last section will be included the facts pertaining to the thickness of the drift beds in Ohio, for the statement and arrangement of which this chapter is mainly written. Five years ago the suggestion that we could ever obtain as much knowledge in regard to the thickness and character of the deposits under which the rock floor of the western half of Ohio is buried as we now have in hand, would have seemed visionary and extravagant to a high degree. Such an opportunity comes but once in the history of a district or a state. It is fortunate that we have been able to secure so large a representation of the results that have been obtained. The figures that the drillers' records have yielded are probably in excess of all the estimates that have hitherto been made. Data are now, for the first time, furnished from which a reasonable calculation can be made as to the total amount of dri.t which has been deposited over parts of western Ohio. For other sections of the state there are not even yet facts enough to render such calculations safe. There are a number of counties in the northern part of the state in which the rock lies, in the main, quite shallow. Erie, Ottawa, Sandusky, Seneca, Wood and Hancock belong in this list, or in other words, the counties constituting the southwest boundary of Lake Erie. The deepest deposits prevail in the two western tiers of counties as far south as Dayton. Another series of heavy deposits extends through several of the central counties. The thickest deposit yet found is at St. Paris, Champaign county. The drive pipe descended there to the extraordinary depth of 530 feet without reaching bedded rock. An account of this remarkable section is found on pages 276-7. At 400 feet a considerable amount of vegetable materials, including fragments of wood and bark, was encountered. An ancient and important drainage channel of pre-glacial Ohio is obviously located, so far as a single point can serve, by this section. The continuation of this channel to the southward is probably indicated in the wide erosion of the cliff limestone on the western side of Clarke county. This valley was pointed out in Vol. I, Geology of Ohio, as the probable location of the Great Miami River in an earlier day (Map-Chap. XIII). To the northwest of Champaign county, through Auglaize and Mercer counties, great erosion in the bedded rocks has been experienced, the entire sheet of cliff limestone being removed in several instances, as shown by the well records. It is obvious that there are possibilities of broad and deep continuous water-ways throughout this region. In the table that follows, the thickness of the varied sheets of drift that cover the western and, to some extent, the central portions of the state is given. The record is made up by counties, and the enumeration is begun in the northwestern corner of the state. The counties are followed from west to east through the several tiers. The records of a few wells in Indiana, adjacent to northwestern Ohio, will also be given in this list. They are as follows: Wauseon, Well No. 1............ 156 feet. Delta, Well No. 1......... 115 feet. LUCAS COUNTY. Monclova.......... 18 feet. Toledo, Rolling Mill Well No. 1.. 110 feet. Toledo, Air Line Junction Well..... ..120 feet. Waterville...... 20 feet. Waterville, Well No. 1 20 feet. |