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clusive to me, and in my opinion a contrary view could only be held in violation of the plainest application of the logic of scientific evidence.

3d. As to the effect of the copper salts upon iron bolts, I unhesitatingly affirm that I know of no condition of actual practice in which decomposing action (electrolytic change) could take place; my views are the same with regard to ships built of iron and lined or sheathed with preserved planking.

4th. “Whether, as a government officer, I am of the opinion that the process should be applied to the timbers of vessels for the purpose of preserving them at least until the actual use of such timber demonstrates the usefulness of the process ?":

I reply that, being thoroughly convinced of the value, I wonld regard its discontinuance as wholly unwise;! I venture to add, absurdly so. In view of the fact that theoretical considerations favor it, and that every test by actual use has shown its value, it should not, in my judgment, be abandoned until it shall be shown by actual trial to have seriously failed.

5th. “As to what, in my opinion, from all my examinations, will be the result of such experiments if put into practice ?".

I reply that the durability of the timber will be very largely increased, that the expenses of repairing vessels will be commensurately diminished, and that, therefore, it would prove an important measure of economy. Very respectfully, and very truly, yours,

WM. N. MEW,

Analytical Chemist and A. A. Surgeon, Ú. S. 1. General BENJ. F. BUTLER,

Washington, D. C.

No. 6.-REPORT OF NAVAL CONSTUCTOR WM. L. MINTONYE.

UNITED STATES NAVY-YARD, BOSTON,

Naval Constructor's Office, March 6, 1882. Sir: In reply to your letter of the 1st instant I have the honor to state that on September 30, 1875, I was ordered by the Chief of the Bureau of Construction and Repair to proceed to Cleveland, Ohio, and carefully examine into the process of preserving timber by the American Wood Preserving Company.

After looking at some railroad ties that were said to have been in use eight years and certainly they looked as if they had, and were sound-and some street pavement that had been down four years, I came to the conclusion that it was worth while to make some practical experiments with this process of preserving timber.

Several small trees were cut down and impregnated, green. A piece of seasoned impregnated timber was found to be rotten after I left and condemned.

I reported that, from what I had seen, timber lasted longer that had been treated than timber not treated under the same conditions, and as the company was willing to send samples to be tried, I recommended that a practical test be given them by putting some pieces in the Trenton, then building at the Brooklyn navy-yard.

The company sent the timber, but I did not hear from my report, and thinking that the authority would be given, I had a piece of each of those trees put in the port battery aft of the quarter-gallery port, and for my own information and in justice to the company I procured the borings referred to.

As I did not feel justified in making any tests in the immediate vicinity of this material, I cannot say how it compares with that, but all that had been cut out was rotten, while those four strakes bored sound.

I would suggest that one of the four strakes, impregnated, be cut and compared with the material in the immediate vicinity. Very respectfully, your obedient servant,

W. L. MINTONYE.

Naval Constructor, U.S. N. Hon. WILLIAM H. HUNT,

Secretary of the Navy.

No. 7.--REPORT OF THE CHIEF OF THE BUREAU OF ORDNANCE.

BUREAU OF ORDNANCE, NAVY DEPARTMENT,

Washington City, February 3, 1882. Sir: Agreeably to your verbal instructions, I beg leave to make the following remarks upon a number of papers (submitted to me) concerning the questions at issue between the department and the American Wood Preserving Company.

On examination, I find that on February 8, 1877, the department made a contract

with the American Wood Preserving Company, calling for the impregnation, by the company's process, and under its patent, of a quantity of timber, certain conditions as to plant, labor, &c., being laid down. Those points in the contract that are material to the inquiry now being made are as follows:

After payment for 100,000 feet at 14 cents per cubic foot, the department to have the right to purchase the works at cost, and to continue the process at its own expense, paying, during the lifetime of the patent, a royalty of 4 cents per cubic foot of timber impregnated.

If at any time after the treatment of the 100,000 cubic feet of timber mentioned above the department is reasonably dissatisfied with the efficiency or desirableness of the process, it may annul the contract, and may require the company to vacate at their own expense and within a reasonable time.

If the department shall not elect to annul the contract or to purchase the works, it shall, from time to time, have impregnated 150,000 cubic feet additional (at the same price), after which it “may” purchase on the former terms.

The question of reasonable dissatisfaction shall be determined by a board of three constructors, before whom the company shall have notice and permission to appear and be heard.

Two years and two months after the signing of the above-mentioned contract, a board of three naval constructors was assembled at the navy-yard, Boston, and made a report (April 12, 1879) to the honorable Secretary of the Navy, in effect as follows:

They saw a car-load of timber placed in a retort, or impregnating tank, and, after treatment, taken out.

They examined the timber, and found the process of impregnation had penetrated every part.

They also examined certain other timber of different kinds which had been submitted to the process, and found in every case the impregnation as perfect as in the first case (on which point they satisfied themselves by the aid of a microscope). They also found that the timber bent as well as that which had not been treated. They further expressed the opinion that more timber should be preserved, designating live and white oak, yellow-pine timber, plank stock, and ships' knees as suitable. The report is signed by Constructors Webb, Wilson, and Boush.

The company was informed of the assembling of this board (by the Bureau of Construction), and permission was given to appear before it.

The papers handed to me contain no further allusion to the matter until December 3, 1880 (one year and eight months after the submission of the report of the first board), at which time a second board submitted a report to Mr. Secretary Thompson. The counsel for the company states (in his written argument) that about June 30, 1880, the company asked that this board might be appointed to determine the valné of the works as they then stood. This board was composed of Naval Constructors Pook, Wilson, Hichborn, Fernald, and Boush ; Surgeon Jerome Kidder, U. S. N., was a member, and apparently also acted as a chemical expert.

The board was ordered to examine the process and the timber impregnated, and to report the condition of the latter as to strength and durability. To report the original cost of the apparatus and its (then) value, and whether, in the judgment of the board, it would be for the interests of the department to purchase the works and continue the process. I infer that this was the board contemplated by article 7 of the contract. It was assembled at the request of the company. The report in substance was as follows: After numerous comparative tests, no difference was found between the strength of impregnated and unimpregnated timber.

It was thought that sufficient time had not elapsed to enable an accurate statement to be inade as to the durability of the impregnated timber. This could best be ascertained after the wood had made one or more cruises.

The question of possible injury to the iron fastenings of a vessel (by electrolysis), owing to the presence of copper solution in the impregnated wood, was touched apod.

The board in this matter based its opinion npon "the information given by Dr. Kidder"; and assuming that the fastenings in the bottom of our ships would always be of copper, the conclusion was reached that no bad effects to the fastenings would ensue "where saline salt or sea-water would injure them."

The exact meaning of this part of the report is not clear to me, but the idea conFeyed is that, assuming the bottom fastenings of a ship to be wholly of copper, the board did not consider that the iron fastenings that might be found above the water line wonld be materially injured by electrolysis. The necessity of a preserving process was asserted, and a continuance of the one onder examination advised, “until a better method is discovered.”

The board also recommended the purchase of the works, giving the original cost as $38,891.95, and the - present" value not over two per cent. less.

There is an appendix to this report, in which Dr. Kidder answers several technical questions submitted to him by the board. His statements are in substance as follows:

Two transverse sections of timber that had been treated were submitted to him.

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They were taken from the middle of the timber-one oak and one pine. He examined fragments taken from the center of each of these pieces. The yellow pine contained copper enough to give a decided reaction. The white oak contained but a very minute quantity. Neither contained any barium. The test was as severe as conld well be made, as the fragments examined came from the center of the logs.

As regards possible injury to iron in contact with impregnated wood, Dr. Kidder says that chloride of copper is likely to be injurious to iron if in contact with it, and moistened

with sea-water. Effect, deposition of metallic copper on the iron, and loss of a proportionate quantity of iron, which combines with the chloride of the copper; slow corrosion results.

The doctor then answers a question put him by the board with regard to the relative merits of sulphate of copper and sulphate of zinc in preserving wood. His answer gives the preference to zinc.

The company's counsel, in his communication to the department, criticises the board for raising the question of the zinc process, but in point of fact it was a very pertinent subject of inquiry, because the board was directed to report upon the advisability of purchasing the copper works, and therefore a consideration of other and perhaps better processes was in order. Such inquiry shows no bias one way or the other.

Dr. Kidder finally remarked that the experiments upon which he based his answer as to the amount of copper and the absence of barium in the wood he examined were “only preliminary and qualitative in their nature.” He apparently does not regard them as conclusive against the possible presence of any minute quantities of barium. He furthur remarks that he had saved certain specimens of the wood for future analy. sis, if that should be thought advisable.

I infer from these statements that he did not consider the test as final and decisive, touching the ability of the process (as a general rule) to force more or less of all the ingredients into the center of the logs; but only that it had not fully succeeded in the particular instance that came under his examination.

I am contirmed in this opinion by the fact that he signed the report recommending the purchase of the works and the continuance of the process.

After the receipt of this report it is probable that the department was not fully satisfied, and hesitated to take final action regarding the company, as the counsel for the company states that the company asked of the department the appointment of a board of scientific experts to examine into the questions reported upon by Doctor Kidder.

I find further a letter from the company's counsel (General B. F. Butler) to SurgeonGeneral Wales (dated January 6, 1861), in which the project of the expert board is discussed, and General Butler says in effect that he accepts the suggestion of an examination to be made by two chemists and microscopist, and further apparently accepts Dr. Flint, U. S. N., in the latter capacity. He states that the company will employ Dr. Mew, U. S. A.' Shortly after this letter was written Mr. Joseph F. Babcock, chemist and Massachusetts State assayer, made a report to the company, a copy of which report I find among the papers furnished me, though it has no direct bearing upon a strictly official inquiry, as it was not made to the department, nor by its order; but to and by direction of the company.

This report is very favorable to the process, both as regards the penetration of the copper and barium into the heart of logs and timber, and also in respect to the preservative action of the ingredients. He knows no valid theoretical or practical objection to the process for timber for all purposes, and states that he saved many specimens of treated wood. There is no record of this report having been submitted to the department.

The board of experts referred to on page 15 was formed by order of the Navy Department; consisted of Surgeon J. M. Flint, U. S. N., Acting Assistant Surgeon W. M. Mew, U. S. A., and Mr. Fred. W. Taylor, chemist of the Smithsonian Institution, and had directions to proceed to the navy-yard, Boston, and determine as follows:

“Whether the company's process is a practical prevention of rot and decay in those parts of the wood which are liable to such action by the elements," and also against * powder post.”

How far the ingredients used are made to penetrate the wood for preservation purposes.

Whether the chemical compositions formed in the wood (by the process) are such as upon well sustained chemical theory would tend to the preservation.

Whether anything in the process would tend to the deterioration of the iron bolts and spikes which go into the wood.

To examine specimens of the wood so preserved as may be authenticated to them to have been in actual use, and report condition and time of use and exposure.

It is my opinion, from the tenor of the foregoing order and from the composition of the board, that the department was still in doubt as to the efficiency of the process, •and therefore decided, at the request of the company, to institute an examination in

a purely scientific manner upon all points not matters of ordinary observation and judgment.

It appears also probable, from General Butler's letter to Dr. Wales, that the company was allowed to suggest one member of the board (Dr. Mew).

The report is dated August 8, 1881, and the ground taken in it, with the conclusions arrived at, are substantially as follows, the sequence being somewhat broken in order to group and bring out the conclusions as plainly as may be.

After calling attention to the impossibility of determining the practical value of the process from theoretical consideration alone, and stating that only by comparative tests of the durability of treated and untreated wood (under like condition) can a positive conclusion on durability be reached, the report shows that limited (but favorable) evidence of the efficacy of the process was presented in the form of impregnated specimens authenticated to have been in use for different lengths of time.

Reports of numerous and prolonged experiments in Europe with wood impregnated with sulphate of copper by a method similar to, if not the same, as under consideration, were submitted, and prove satisfactorily that sulphate of copper is of practical value for wood preservation from rot and decay.

The testimony is equally conclusive that sulphate of copper alone is only a temporary protection against teredo.

Numerous sections of pine and oak timber were treated and cut in presence of the board, and repeatedly and carefully analyzed.

Copper was found in all the specimens—it appears to have penetrated the sap wood readily, but with greater difficulty the heart of oak and pine, in which parts it was found in very smali quantity (except in two specimens which contained a considerable amount).

Barium salt penetrated less completely than the copper-traces were found in most of the section, but not in all. In some heart wood it was found in only the minutest appreciable quantity.

Compounds of copper with the organic constituents of the wood strongly resist pu- ! trefaction; such compounds were found in the wood examined.

Whenever the solution of copper and barium met, chloride of copper and sulphate of barium were found.

Chloride of copper, and such sulphate of copper as might escape the action of the chloride of barium, would also tend to wood preservation.

Sulphate of barium exercises no chemical action on the wood or poisonous action on the organisms (teredo?). The microscope and the minute quantity found show that it did not to any appreciable extent occlude the pores of the wood.

Theory does not show that it tends to wood preservation.

With regard to the injury to be apprehended to iron bolts, &c., in contact with the impregnated wood, the board declared that copper salts in solution and in contact with iron tends to deteriorate the latter.

In the case of this wood, however, the quantity of copper salt present is probably not sufficient to effect practical injury. As long as the wood is dry the action will not take place.

This report is signed by all the members. Dr. Mew, however, appended some remarks detining more exactly his opinion upon two points:

First. With regard to the preservative properties of the barium, he states that had a much larger quantity of chloride of barium entered the wood, some of it would probably have escaped contact with the sulphate of copper, when that which so egcaped would be free to combine with the organic matters of the wood, forming compounds as efficient for preservation as the copper salt. This statement is predicated upon the opinion that a much larger amount of barium chloride conld have been injected into the wood than was actually found there,

The ground for this opinion does not appear.

Second. With regard to the effect of the treated wood upon iron, he thinks the probability of free copper salts in the wood is only remote; but granting it for the sake of argument, he thinks the conditions pecessary to injury could not really exist, because in order to such injurious action there must be a free solution of the salt in contact with unprotected iron, and he takes the ground that if the solvent (moisture) can enter the wood, the resulting solution must escape by diffusion in the surrounding menstruum in obedience to well-known laws."

It would appear that the above statement does not give much weight to the affinity of the copper for the iron, and also, perhaps, overrates the facility of diffusion of the solution.

This is the last report upon the merits of the process, and is apparently the one to which most weight should be attached, as it is the most precise and exhaustive in its statements. It takes grounds partly mfavorable to the process in two respects:

First. By declaring that sulphate of barium exercises no chemical action on the wood or poisonous action upon the organisms (worms), that it does not stop the pores, and that theory does not show it to have a tendency to wood preservation.

Second. By declaring that the penetration of copper into the hearts of logs or tinber is comparatively slight, and that of barium barely appreciable.

It is favorable in that it declares

First. That compounds of copper with the organic matter in the wood strongly resist putrefaction, as also do the chloride and sulphate of copper. Dr. Mew further finds that part of the chloride of barium may under certain conditions produce a like effect.

Second. In that it inclines the view that practical injury to the iron by electrolysis will probably not take place.

This board was not instructed to express an opinion as to the advisability of continuing the process or purchasing the works.

In the endeavor to arrive at å decision upon this matter an inportant question arises as to the relative weight to be given to the various papers and reports, offered and unofficial, which have been handed me for examination.

The unofficial papers are as a rule considerably more favorable to the process than the official ones, and, not being so guarded in tone, seem to me to merit less weight, besides they are not addressed to the department, upon which the burden of a decision rests, but to the company or its counsel. I shall then rely mainly upon the official reports in forming an opinion as to the general efficiency of the process.

The two official boards that subjected numerous transverse sections of treated timber to analysis agree substantially on the following points :

A very small quantity of copper salts and only the remotest appreciable quantity of baric salts was found in the heart of the treated wood; of the latter salt, sometimes none could be found.

These facts are unfavorable to the process, as they imply deficiency of penetration.

With regard to the preservative merits of the process, the last is the only official board that expresses an opinion.

This is favorable to the influence of copper, but unfavorable to that of barium, no preservative action being attributed to the latter.

The general conclusion to be drawn on this point is that copper preserves by combination with the organic matter in the wood, and does so in a satisfactory manner when a sufficient quantity is present.

One expert expresses the opinion that free-barium chloride would help if certain rather remote circumstances favored.

The unofficial papers assert the thoroughness of the process, its preservative excellence, and its durability. One of these is by Dr. New.

From all the foregoing I think we may conclude that the process is calculated, in a chemical point of view, to preserve wood ; but owing to difficulties (probably of a mechanical nature), the process is not thorough and certain in practice when free penetration to the heart or center of large timber is required.

This much being settled, it becomes necessary to determine whether the department is in the phraseolagy of the contract) “reasonably dissatisfied with the efficiency or desirableness of the process"; and on this I will give the opinion that, though the process is not by any means perfect, I do not think on the whole the department should take the ground of “reasonable dissatisfaction," especially at this late date.

Two boards of naval constructors and one of chemical experts have had the matter fornrally before them, and each in its report has failed to declare or imply reasonable dissatisfaction. Indeed both boards of constructors recommended a continuation of the process, and the second one (which was ordered to express an opinion on this point) recommended the purchase of the works.

If, then, the department decides not to declare itself dissatisfied, two courses are left open by the contract:

1st. Buy the apparatus at about $40,000 and continue preservation of wood at the expense of the department, paying the company a royalty of 4 cents per cubic foot foot during the life of the patent (about six years).

2d. Do nothing towards annulment of the contract or purchasing the apparatus; simply assume that the contract has expired by fulfillment (as shown in the following paragraph) and cease ordering wood impregnated. Then in time either inform the company that it must remove the apparatus from the navy-yard, or else make a new contract, as will be adverted to further on.

Article 6 of the contract requires that if (after the impregnation of the first 100,000 cubic feet) the department neither annuls the contract nor purchases the plant, it shall from time to time cause 150,000 cubic feet (“additional") to be impregnated at $21,000. I construe the word " additional,” as meaning additional to the first 100,000 cubic feet—that mentioned in article 4 of the contract.

I find, on inquiry at the Bureau of Construction and Repair, that the company has treated in all 388,555 cubic feet. Deducting the 100,000 cubic feet required by article 4 of the contract, there will remain 288,555 cubic feet, which should be construed as

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