Box 10, Folder 6: Correspondence January-June 1869

(Copy) Milwaukee Wis. Jan. 18th 1869

Dear Sir,

Please let me know whether you will, and at what cost, apply the proper tests of the value of some building stones offered for our new Court House, a building about to be erected at a cost of over half a million of dollars. I write on behalf of the committee having the matter in charge and hope you will find it convenient to comply with our wishes. We are offered a red standstone from Lake Superior -- several limestone and our own Milwaukee Brick.

We shall want to know the specific gravity, and the power of absorbing water &c after the manner of your Report 1866 p. 281.

I send you a new Geological Map of Wisconsin which I hope may prove interesting.

Yours truly I. A. Lapham

Dr. F. Sterry Hunt

Copy Milwaukee Jan. 9. 1869

Dr Sir

I have had the honor to receive the printed circular of the special committee of the County Board of Supervisors, appointed to inquire into the suitableness of the Lake Superior Sandstone quarries on Bass Island, one of the Apostle group, for facing the walls of the building about to be erected by the Board for a Court House; and you do me the further honor to say that something valuable will be expected from me, and that great confidence will be placed in what I may say about matter. I feel therefore the responsibility of the task and the necessity of the great caution in whatever I may say or do in the premises.

The value of a building stone depends much upon its strength, or ability to sustain great weights without being crushed, and in this respect the Bass Island sandstone -- so far as I can judge from mere inspection -- must be placed low down in the scale. But as it is to be used only as a facing to the wall, and not therefore required to sustain much weight, it is, doubtless sufficiently strong to answer the purpose for which it is to be used in the

construction of the Court House.

Perhaps the greatest defect in building-stone, next to that of a want of strength, is porosity, or openness of grain, enabling it to absorb large quantities of water, which by alternate freezing & thawing causes the surface to scale off, and thus gradually destroy the structure. This process is materially aided when minute seams or cracks are found, in which the water penetrates. While in this respect the stone in question is not free from serious objection, being porous, and capable of holding a large amount of water, yet as it is comparatively uniform in texture and free from small cracks and seams, it may be found capable of resisting this cause of decay, especially as it will, in a considerable degree be protected from rain by the projecting roof and porticos.

The presence of alumina (clay) in the composition of sandstone renders it more retentive of moisture, and therefore more liable to decay. There is reason to believe that there is some alumina in this stone.

The expansion of stone by an

increase of temperature is very considerable and is more in sandstone than in limestone, being best in granite; but the walls to be faced are so much broken by pilasters windows, and doors, that no serious trouble need be apprehended on this account.

The fineness of grain, the freedom from cracks and seams, and the absence of iron otherwise injures some of the sandstones of Ohio, are qualities of this stone that go to recommend it to public favor.

Though no very intelligible and certain opinion can be given, as to the value and durability of this stone until accurate experiments shall be made to show its strength, its chemical composition, its power of absorbing water etc. yet upon consideration of the facts above stated we may conclude that the Bass Island sandstone may, without much danger be used as contemplated.

I avail myself of the opportunity to suggest that we have no easily accessable stone in Wisconsin, suitable for the steps leading up into the new Court House, as the nuisance at the west end of the United States Court House

and Port Office will attest, and recommend that a few stones be obtained for this use from the Quincy granite quarries near Boston, which is so hard and durable as to withstand through all time the constant wear of such a position.

Very respectfully I. A. Lapham

Ch. K. Wells Chairman Special Com. Etc.