wright who was with him that he considered her in much better order than is usual in ships of her age. The ship was then fifteen years old.

Professor Faraday, lecturer at the Royal Institution, London, explained in one of his lectures in 1833 that the preservation of the wood arises from a chemical combination which takes place between the corrosive sublimate and those albuminous particles which Berzelius and others of the highest authority consider to exist in, and form the essence of, wood; which, being the first parts to run to decay, cause others to decay with them; also, after witnessing various trials, extending to five years, in the fungus pit at Woolwich, in all of which the prepared timber and canvas came out perfectly sound, whilst the unprepared were decayed, he gives his opinion that the process would be found effectual in preserving timber, and that the improvement would be so great as fully to justify its extensive application.

Professor Faraday experimented upon the penetration of the solution into the wood by the application of hydrosulphuret of ammonia, which will turn black on meeting with mercury. In a cube of elm he traced the corrosive sublimate to the depth of from one-fifth to one-fourth of an inch; in a cube of oak, one-fourth of an inch; in a cube of fir, from one-eighth to onesixth of an inch. In the latter, the resin in the wood had probably offered the obstruction to penetration.

Plate I. illustrates an experiment recently made in Lowell on the penetration of the mercury, in a section of two-inch spruce plank kyanized in 1890. The dark shaded part around the edge shows the penetration of the mercury as indicated by the application of a few drops of hydrosulphuret of ammonia. The penetration can be easily traced to a depth of about onefourth of an inch.

In considering this process, Professor Faraday has always looked upon the excess of corrosive sublimate in the parts towards the exterior of the timber as a most important condi

tion; and a strong argument with him in favor of the process is the well-known fact that such matter will gradually penetrate the wood by those forces which tend to give a uniform distribution of fluid within the pores of any porous matter, and which will be influential, though the pores be not full of fluid, the wood being in what is usually called a damp state.

There is one other consideration which was of importance to Faraday in forming a judgment on this process; it is, that, where the exterior is preserved from change, the chances that the interior will decay are greatly diminished. For instance, piles or timbers charred on the outside preserve the interior parts from decay for a much longer period, so he thinks it safe to conclude that even an external preparation of timber would greatly diminish the probability of internal decay; and this, in combination with the gradual penetration of the substance to the centre, is the reason why he entertained little doubt of the value of the process of kyanizing.

But kyanizing has gone out of use in England. It was abandoned many years ago. Mr. JAMES B. FRANCIS, after a most careful investigation of the matter in 1849, attributes the cause to be entirely independent of the success of the process itself, when properly applied.

Among the causes that led to the abandonment of the kyanizing process in England may be mentioned:

1. The mismanagement of the celebrated Anti Dry Rot Company, which was a disgrace, and which created a universal prejudice against the whole subject of the preservation of timber by kyanizing.*

2. The Rothschilds had a monopoly of the product of the Spanish quicksilver mines, and practically controlled the market, as they do to-day; which had, and now has, the effect of materially increasing the cost of corrosive sublimate.

The Anti Dry Rot Company, London, purchased the patent for England of Mr. Kyan. Preparations were made for an extensive introduction of the patent through the country; but, after a brief period of considerable notoriety, the manager ran off with upwards of £70,000, which ruined the company.

Posts planted to equal depths in the yard of Proprietors of Locks and Canals, Lowell, Mass. Those in front row were kyanized in 1862 and those in back row were left in the natural state. The boxing about the kyanized specimens protect them where pieces for exhibition have been taken out. All specimens in the back row are boxed to prevent them from falling to pieces.

Photographed in 1891.