GEOLOGY. 275 



disintegrated at the surface, and some were so much and so deeply 

 affected, that it was necessary to remove them. The Capitol is a 

 massive building, its walls are thick, and maintain a certain equality 

 of temperature, changing' slowly with the changes in the temperature 

 of the air. In a change from cold to warm, the walls remain for a 

 time cold, and there is condensed upon them a portion of the moisture 

 of the atmosphere, as upon a pitcher containing ice-water in a sultry 

 day. The stone, being porous, readily absorbs the moisture, and the 

 natural cement, which seems to be slowly soluble in water, is dis- 

 solved, or otherwise loses its adhesive power, and the stone crumbles 

 to sand. A thick coat of paint, carefully applied from time to time, 

 has been resorted to, to preserve, and no doubt tends to preserve, the 

 building ; but unless some other and more permanent protection be 

 resorted to, it is destined to early dilapidation. If left wholly unpro- 

 tected from atmospheric action for one fifth of the time that marble 

 structures are known to have stood, this noble edifice would become a 

 mound of sand. 



" The Treasury building and the present Patent-Office building 

 are of the same material, and, having been in no manner protected, 

 already show signs of decay. The cornice of the Treasury building, 

 which exposes a heavy mass of stone to atmospheric action, begins to 

 be moss-grown ; and pieces of the Patent-Office building have crum- 

 bled and fallen. Besides its tendency to disintegration on exposure, 

 the stone in its best condition is weak, offering little more resistance 

 to a crushing force than common brick. These buildings cannot, with 

 all possible care, be long preserved by the means at present adopted. 

 But if the stone could be rendered permanently and absolutely im- 

 permeable to moisture, the principal difficulty would be removed, and 

 this may, perhaps, be done by some means known to the arts, or which 

 may be discovered by experiment. For this purpose I would recom- 

 mend that specimens of the stone be carefully analyzed, and that a 

 series of experiments be tried with a view of finding some chemical 

 agent, the application of which will prevent its absorption of moisture, 

 and thus strengthen and render it durable." 



At the meeting of the American Association at Cambridge, in 

 August, Prof. Walter R. Johnson stated that the materials of which 

 the Washington Monument at Washington is being constructed are 

 totally unfit for the purpose. He exhibited specimens of the marble, 

 and mentioned many experiments that had been made, which render 

 it not at all improbable that the monument will fall to pieces from its 

 own weight before it is completed. A specimen of the stone, four 

 cubic inches in dimensions, sustained a weight of only 9,000 pounds, 

 while one cubic inch of good material sustained a weight of 18,000 

 pounds. 



METEORITE IN NORTH CAROLINA. 



ON the authority of a communication from J. H. Gibbon, Esq., of 

 the Branch Mint at Charlotte, North Carolina, we give a condensed 

 view of facts regarding a fall of meteoric masses in that State. 



On Wednesday, the 31st of October, at 3, P. M., several persons 



