664 REPORTS OF THE BUILDING COMMITTEE. 



mountain ash, lime tree, evergreens, (including the several varieties of pine3,) aspen, 

 and sycamore. 



And, on motion, the committee adjourned. 



Nineteenth Meeting, March 80, 1847. 



Present, Messrs. Seaton and Owen. 



The chairman submitted from Dr. Owen the following report on the Aquia creek 

 and other Stafford county freestones. 

 To the Building Committee of the Smithsonian Institution : 



Gentlemen : On the 26th of March, agreeably to a resolution passed by your 

 committee, I proceeded down the Potomac to examine the quarries of freestone of 

 Stafford county, Virginia. 



On arriving at the mouth of Aquia creek, which is 50 miles from "Washington, I 

 learned that the quarries which have been chiefly wrought for the public buildings 

 lie about seven miles up that stream. 



On my way I stopped at Major Brook's, five miles on this side of Fredericksburg, 

 to obtain some information about the route. Learning from that gentleman that 

 there were several good quarries of freestone in his immediate vicinity, on Accokeek 

 creek, and near the line of the railroad, I determined to visit them. 



I found them situated on both sides of Accokeek creek, close to Major Brook's 

 mill-dam. The upper beds here are about six to eight feet above the level of the- 

 creek, and are of a coarse texture, approaching to the nature of a conglomerate, 

 Beneath, about four to five feet above the level of the creek, the rock is finer-grained, 

 with some yellow and gray streaks, (see No. 26.) The rock on this part of Accokeek 

 is below the level of the water when the flood-gates of the mill-race are closed. It 

 was here that the rock of which the mill-dam is constructed was quarried. So far, 

 it has stood the test of exposure in this situation well. The abutments of the rail- 

 road viaduct over Accokeek creek are constructed of rock from these quarries ; and 

 though the selection does not seem to have been very carefully made, it still remains 

 a substantial work. 



The quarries on Aquia creek most convenient to navigation, and those which 

 furnish a rock lightest colored, finest grained, and most uniform, are situated on 

 what is called the Island, being a neck of land seven miles by the course of the- 

 stream from its mouth. This island is elevated 15 to 20 feet above a flat swampy 

 plain, which surrounds it on every side, and which, in the early settlement of the 

 country, was an inland bay, navigable for small craft. 



At present the waters are contracted into the narrow channel of Aquia creek, 

 about 15 feet wide. 



One of the quarries on this island is known by the name of Stewart's quarry, but 

 now owned by Mr. Symington, of Baltimore. To the north and south of it are two 

 others, belonging to the United States. 



The columns of the cast portico of the capitol, each of a single piece weighing 18 

 tons, were obtained at these United States quarries. 



The principal ledge hitherto worked here has a covering of only two or three feet 

 of earth, and lies nearly horizontal, in a vast bed from six to eight or 10 feet in 

 thickness, without the slightest apparent seam. For this reason, though the bed is 

 so near the surface, it has been quarried at great expense, at least by the method 

 hitherto employed, which is to groove it behind and on one side two feet wide, (or 

 sufficient to receive a man,) in a vertical direction, even to its base, and then " loft ' r 

 it off in a horizontal direction by the introduction of wedges at the bottom of the 

 bed in the direction of the stratification. 



This Island freestone is of light color, almost white when dry ; and is equal, if not 

 superior, in texture and color, to any of the sandstones in this neighborhood. That 

 on Symington's tract (see specimen No. 27) is rather of a finer grain than in either- 

 of the United States quarries ; (see specimen 28.) 



Part of the rock employed on the inside of the Post Office was procured on this 

 island. 



Numerous other quarries are found in this vicinity, many of them well opened and 

 wrought to a considerable extent. None are, however, immediately on the bank of 

 Aquia creek. Some lie to the east of the swamp, in the ridge which lies between 

 Aquia creek and the Potomac river, and distant from the latter stream from three to 

 seven miles. These were not visited, as there were no means of crossing the swamp. 

 Others have been opened in many places along the banks of Piocky run. 



The stream empties into Austin's run, which bounds the island and swamp on the- 

 southwest. That nearest to Aquia creek is distance from half a mile to three quarters. 



