6|San Francisco |1876| " | " " | " | " |C.S.  Stewart | | | | | | | 7|Milwaukee |1876| " | " " |Pavement |Favorable,|Schlitz Bg. | | | | | | 1882 | Co. 8|Norfolk, Va. |1876| " |Hackmatack|Teredo |Failure |P.C.  Asserson | | | | | | | 9|Charlestown, |1877| " |Various |Laboratory|Favorable |J.F.  Babcock | Mass | | | | | | 10|Wabash R.R. |1877| " |Ties |R.R. track|Unfavor. |R.A.  Houghton | | | | | | | 11|Wabash R.R. |1878| " | " | " " | " |W.S.  Lincoln | | | | | | | 12|New York, |1879| " | " | " " | " |C.  Latimer | Pennsylvania,| | | | | | | and Ohio R.R.| | | | | | 13|Lake Shore and|1879| " | " | " " | " |R.A.  Houghton | Michigan | | | | | | | Southern R.R.| | | | | | 14|Cleveland and |1879| " | " | " " | " |C.  Latimer |Pittsburg R.R.| | | | | | 15|Charlestown, |1879| " |Spruce |Sidewalk |Success |S.G.  White | Mass | | | plank | | to 1882 | 16|Baltimore and |1879| " |Ties |R.R. track|Too recent|J.L.  Randolph | Ohio | | | | | | 17|Hudson River |1869|Hamar | " | " " |Success |E.W.  Vanderbilt | R.R. | | | | | | 18|St. Louis |1882|Fladd | " | " " |Too recent|H.  Fladd --+--------------+----+--------+----------+----------+------
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COMMENTS ON SULPHATE OF COPPER EXPERIMENTS.

The first experiment was carried out by Mr. W.W.  Evans, on the Southern Railway of Chili, in 1857, and he informs your committee that in 1860, when he left that country, the ties were still good and in serviceable condition.

We give herewith, in Appendix No. 16, an interesting letter from Mr. E. Pontzen to Mr. Evans, on the subject of the Boucherie process.

Experiments Nos. 2 to 16, inclusive, were all tried with various modifications of the sulphate of copper process as introduced by Mr. W. Thilmany in this country.  They date back to 1870 (experiment No. 2), when Mr. Thilmany was working and recommending the methods of vital suction and of the Boucherie hydraulic pressure system.  After describing the foreign methods of injection with sulphate of copper, he states in his first pamphlet (1870):  “This process resulted very satisfactorily, but it was found that the sulphate of copper became very much diluted by the sap, and when the same liquid was used several times, the decaying substance of the sap, viz., the albumen, was reintroduced into the wood, and left it nearly in its primitive condition.”