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and within the valley of the Des Moines River, from a point a few miles above Pella to the south boundary of the county. Just north of Pella, Philip Mathes has quarried much of this rock for both common and dressed work, principally the latter. The material is of good quality for caps, sills, lintels, dressed walls, etc., and is much used for such purposes. Wherever the limestone is found it may be made to produce excellent lime and much is already burned in various places.
"At Red Rock, the coal-measure sandstone has a full bluff exposure upon the left bank of the Des Moines. It is here mostly of a light, brick-red color, and much of it is hard and firm enough for use in good buildings. It may be quarried in almost any desired shape, size or quantity."
We herewith give the analysis of some of the coal of Marion county as made a few years since by the State Geologist. Before giving the analysis it will be proper to state that there are four conditions which must be taken into consideration in estimating the comparative value of coal. They are given as follows:
First. The value of coal as a fuel is inversely proportional to the amount of moisture contained in it, that is the more water it contains the less is its value. Moisture is a damage to the coal, not only because it takes the place of what would otherwise be combustible matter, but also because it requires some of the heat generated by the burning of the combustible matter to transform it into steam and thus expel it. It will thus be seen that the presence of large quantities of moisture in coal seriously impairs its value. In looking over the analysis given it should be remembered that some of the coals were taken fresh from the mine, others had been kept for some time in a damp room, while others had been subjected to the high temperature of a heated room for a considerable length of time.
Second. The greater the per cent of ash, the less the value of the coal. Third. The more fixed carbon which the coal contains, the greater its value.
Fourth. The same holds true with regard to the volatile combustible matter, to a certain extent, the precise limits of which cannot be determined until we know the composition of this combustible matter.
In analyzing Marion county coals the State Geologist first took two samples from Bousquet's mine at Coalport.
No. 1. Sample from the bottom of the, mine. The coal was found to be hard and brittle. Strata were quite irregular. Numerous thin seams of calcareous matter traversed the coal transversely to planes of stratification. Some mineral charcoal was found upon one of its plaues. The sample was glossy upon its edges. The coke was found to be compact and had a metallic luster. The ash was of a red color, slightly tinged with yellow.
No. 2. Sample from the top of the same mine. This coal was not as glossy as that from the bottom of the mine. The seams of calcareous matter were not so distinct, and upon being broken scarcely any impurity appeared. The coke was of a dull lead color and had a semi-metallic color. The ash was of a chocolate color.
The next samples were from a mine four miles east of Knoxville. No. 1. Sample from top of the mine; coal hard and compact; well laminated, glossy and clean; but little calcareous matter; coke of metallic luster and quite porus.
No. 2. Sample from bottom of same mine. The appearance very similar to sample No. 1. Same pyrite was found on its face.
The next samples are taken from a mine near Marysville.
No. 1. Sample from top of mine was found to be composed of laminæ of a thickness ranging from one-eighth to one-fourth of an inch, and separated from each other by thin layers of mineral charcoal.
No. 2. Sample from bottom of same mine; coal more compact than from top.
We herewith append an article originally published in the Knoxville Voter in 1871, written by W. P. Fox:
"EDITOR VOTER-After explorations made during the past two weeks, throughout this section of Marion county, I herewith submit the result of the same to the public:
"That Marion county is one of the heaviest coal counties in the State there cannot be the slightest doubt. The carboniferous system—the great coal-bearing system of the earth's crust-is the foundation upon which Knoxville rests. This system attains to a great depth throughout this section of the county, and must necessarily bear from three to five beds of coal. We are positive as to three beds, or veins, and from all indications we believe there must certainly be all of two veins more underlying the other three beds. Although this county is underlaid with such vast deposits of coal, yet it is the least developed (as far as known) of any coal county in the State-there not being a large mining company in operation in the county.
"At this point I will give the altitude of various points as taken from railroad surveys. At the great divide between the waters of the Mississippi and Missouri, at a point were the B. & M. Railroad crosses in Union county the elevation is some 800 feet higher than at Burlington, on the Mississippi. At Knoxville it is some 350 feet higher than at Burlington. The altitude is some 250 feet higher at Knoxville than it is at Eddyville, at low water mark on the Des Moines. There is a fall from Des Moines to Eddyville of 125 feet, and a fall from Eddyville to the mouth of the Des Moines River just below Keokuk of 125 feet. Therefore the great rise of the elevation from the Mississippi is to the northwest, making the great dip to the southeast. The table-lands of Knoxville are two hundred feet higher than the bottom-lands of the Cedar at Marysville. Knoxville is some 175 to 185 feet higher than at Amsterdam or the second crossing of the Des Moines River from Knoxville to Pella. By this we arrive at the trend and dip of this section of the country. In Marion county, that is in this section of it, the waters seem to run to the east and northeast. From this we form our base of stratification, etc., and branch out.
"By these altitudes we find that the lands surrounding Knoxville, that is the high lands, stand high in the scale; and from various developments already made, we are led to conclude that the coal-bearing system of this county is very deep. Near Knoxville there is a very singular little branch or stream, called Competine. The Competine (both branches) heads in section one, about a half mile west from the court-house, and takes a wind.
ing course southeast till it reaches the bridge directly south of the city, whence its course is nearly due east for about a half a mile, when it changes to the northeast, and keeps this course till it empties into the Whitebreast some seven miles northeast of Knoxville, within a mile of its mouth. This stream is what I term a grand 'fault,' or this stream passes along in the fault, making around on three sides of the city. Again, northwest of the city a small branch heads, passing through land owned by E. Baker, thence northeast and east through land owned by Cunningham and Boydston, just south of Stephen Woodruff's farm, thence through Gregory's farm, and thence to its confluence with the main branch of the Competine, some 1 miles northeast of the city. This is what I term a grand 'wash.' Therefore a fault and a wash entirely surround the city of Knoxville. Thus the Competine virtually drains the whole country for over a mile each way around Knoxville, taking in all the little sloughs, tributaries and branches within a mile and a half south of the city, beyond which point the little rivulets and branches empty into English Creek, which drains all of that section of the county.
"We therefore have a large body of land where Knoxville stands, which is undisturbed, high and commanding, with a 'fault' and a 'wash' passing entirely around it, exposing the coal formation at every point of the compass, with its clays, shales, slate, soapstone, coal-brasses, oxides, carbonates, sulphates and all the various essences of the coal itself, which indications are God's great Index Book, and cannot lie; which proves to us conclusively that the city of Knoxville stands upon vast deposits of bituminous coal. I have visited numerous coal banks along the Des Moines in this county, and explored the saine; also the old and new coal banks around Knoxville in different directions, taking pains in examining the roofing, the number of the vein they were working, or had been working, its quality, and all the points necessary in order to base my conclusions in regard to the extent and vastness of the coal deposits.
"Coal veins are beds, classically speaking, all numbered from the bottom up; but the mining world generally count from the top down. We will therefore count from the top down. The first bed of coal, as far as developed in this section, ranges from one foot to three and four feet in thickness, and has a shaly sandstone substance, intermingled with a soapstone shale, for its roofing. Roofing is generally very poor, and the coal, as a general thing is of an inferior quality and not worth working. The second bed or vein of coal, as developed, is a heavy vein, ranging from four to seven feet in thickness. Its average is good, yet it could be bettered by getting farther into the body of the high land. Roofing, steatite slate or black soapstone, with abundance of shaly substance above. Roofing is generally good. The third vein has been but very little developed in this section of the county; yet we readily see the cropping of it in different places. This vein will prove to be the best and purest coal ever worked in this county. It will range from four to eight feet in thickness, with a superb roofing of bastard lime-rock and hydraulic slate. The best mode of work, ing this vein of coal is by shaft. In this way the heavy body of the coal can be tapped at once, and rooms run off from the bottom of the shaft in various directions, and the coal and water raised by the same power either by steam or horse-power. This is the proper way by all odds, and the cheapest in the long run, for working a first-class coal bank, Either in working this or the second vein, I would always advise that it be
worked by shaft, as there is more money in it, both for the niner and the owner of the bank.
"The various places where the second vein of coal has been worked in this part of the county, and now abandoned, and also the banks now being worked, have been commenced in most instances in the very poorest places that could have been selected, the roofing being rotten and bad, until they run, at great expense, far into the bluff or hill. The coal is also inferior, until its solidity is reached.
"Much care and judgment should be taken in selecting sinking points for proving and opening coal beds. If a person thinks he can sink a shaft wherever he pleases and strike a bed or vein of coal, he is most wofully deceived, and will soon find out his fool-hardiness after being relieved of a few hundred dollars. If a shaft should be sunk in a 'fault,' or a grand 'wash,' or in a 'creep,' coal never could be reached in paying quantities. And there are numerous other difficulties to encounter in proving coal beds where the coal may be missed altogether by sinking in the wrong place. Good roofing and solid coal, where the thickness will justify working, are the main points of coal-mining. Yes,' says one, but how can one person tell where to open a vein or body of coal, any better than another, so as to tap it in the right place?' For a person to ask this question, proves his ignorance, and lack of good practical, common sense. How does a doctor know any more about medicine and the human system than any one else? How does an astronomer know more about the heavenly bodies that revolve through space than others? Why do some men know more about science than others? Why has not every man a brain as well developed as his neighbor's? For reply to all such questions asked, the questioner will do well to consult his own ignorance.
Experience, joined to common sense,
"In the meadow-lot belonging to J. L. McCormack, near his residence, is a good point to tap a heavy body of coal by shaft. Here the coal would be good, and also the roofing-that is, overlying the second and third beds. The first vein would not pay, but the second would pay heavy, and also the third. The depth would not be great to the second bed at this point. This land is in section 7.
"There is also a heavy body of coal underlying a portion of the land owned by E. Baker, Esq., situated a little northwest of the city, being in section 1. There is a very good point here to tap the coal, where it would pay heavy to work, on the south side of the branch. The first vein would be passed through in sinking a shaft to the second vein. The second vein or bed would pay to open here. The roofing would be good. It would have to be opened by shaft; but the depth to the second vein at sinking point would not be great. I have examined several tracts of land within three and four miles of Knoxville, of some of which I will briefly speak:
"Underlying a heavy portion of land owned by R. H. Underhill, of Knoxville, situated some two and a half miles east of the city, on section 10, without doubt three beds of coal exist. A careful survey of lands surrounding this land with the different coal banks already opened leads me to this conclusion. This land is high and commanding, situated on the line of the A. K. & D. Railroad. The second and third veins or beds of coal underlying