600 REPORTS OF THE BUILDING COMMITTEE. 



he be requested to visit the different sandstone quarries in the vicinity of Seneca 

 creek, and make a report on their extent, and their general character and fitness for 

 furnishing a suitable material for the Smithsonian building. 



Mr. Owen submitted the following letter : 



Baltimore County, March 6, 1847. 



Sir : Yours of the 1st instant has been duly received, and, in reply, I would state 

 that I am almost entirely uninformed as to the sizes of the stone required, and am at 

 a loss how to propose for the material. 



If you would do me the favor to send me, immediately, a specification of the stone 

 wanted, I will then propose for the stone, whether the rubble stone is to be worked 

 and made ready for the mason, or in the rough state from the quarry. 



You may have misapprehended my former letter ; that was for the rough and the' 

 ordinary size building stone. As to the quarry-right, the price would depend much 

 on which quarry you might want the right to quarry into ; I have several. I should 

 be much pleased to furnish you with what stone you may want, should you determine 

 to use our stone, and think the material to be as good as any in our neighborhood. 



Please write immediately on the reception of this, in order that I may have time 

 to propose by the 20th instant. I was this day with some of the directors of the Sus- 

 quehanna road, and I think they will agree to take the proposed amount — that is to 

 say, 2.V cents per mile. 



"Respectfully, your obedient servant, SAMUEL "WORTHINGTON. 



Hon. R. D. Owen, Chairman of Building Committee. 



On motion of Mr. Seaton, it was — 



Resolved, That the reply to the above be postponed until the return of Dr. Owen 

 from Maryland. 



The chairman laid before the committee the following report from Dr. Page, 

 appointed to make examination of building materials : 



To the Building Committee of the Smithsonian Institution, on the action of frost 

 upon certain materials for building. 



Of the twenty-five specimens of stone submitted to me for examination with 

 reference to their relative properties in resisting the disintegrating action of frost, I 

 have been able to investigate but twenty-two ; the remaining specimens, marked, re- 

 spectively, 1, 9, 5 D, being too small to submit to the test. It was thought desirable 

 to ascertain their specific gravities, with a view to determine if any connection existed 

 between their densities and liability to dilapidation. The result leads us to infer that 

 such relation does not exist, and that the texture of the stone, without reference to 

 density, determines the frangibility under the influence of frost. Resort was had in 

 these experiments to an imitation of the operation of freezing water after the pro- 

 cess described by Brard, a French chemist, in the " Annales de Chimie et Physique, 1 ' 

 vol. 38. The details of the process will presently be given. 



The absorption and subsequent freezing of water within the stone would have been 

 a more energetic mode of action ; but the undertaking would prove one of consider- 

 able practical difficulty, and, on the whole, not so reliable as an experiment, unless, 

 perhaps, the circumstances were such as to admit of their exposure to natural freezing 

 under favorable circumstances. 



The process of Brard consists in substituting the crystallization of the sulphate of 

 soda for the freezing of water, and has met with the approval of many French archi- 

 tects and engineers, as the results accord with their experience. In the freezing or 

 crystallization of water, the expansion is such, that the crystals float ; while in the 

 crystallization of sulphate of soda, and other soluble salts, the crystals sink in the 

 solution ; but, notwithstanding, the exertion of the crystalline forces of these salts is 

 sufficient to produce decided impressions upon the hardest of building materials in a 

 few weeks. 



The specimens of stone furnished me by your Board were all numbered as accord- 

 ing to the subjoined table ; and it may be proper to remark, that their localities and 

 respective values, as usually estimated, were unknown to me until after the results 

 of the experiments had been laid before you and approved. 



Six numbered specimens were also handed to me by Mr. Dewey, and are marked, 

 respectively, 1 D, 2 D, &c. The specimens were cut into inch cubes ; three of the 

 whole number being of insufficient size, were laid aside, as above mentioned. The 

 cubical blocks, suspended by strings, to which the respective numbers upon labels- 

 were attached, were first immersed in a boiling solution of sulphate of soda, saturated 

 when cold ; and after remaining half an hour in the boiling liquid, they were- 



