. The
result was not satisfactory, as might be expected from the fact that
lime is a comparatively weak antiseptic (52.5 by atomic weight, while
creosote is 216), and from the extreme tediousness of three months'
soaking.

Experiments Nos. 5 and 8 were tried with sulphate of iron, sometimes
known as payenizing, and the particulars of the former have been
furnished by Mr. I. Hinckley, President of the Philadelphia, Wilmington,
and Baltimore Railroad, to whom your committee is much indebted for a
large mass of information on the subject of timber preservation.

Mr. Hinckley has had longer and more varied experience on this subject
than any other person in this country. Beginning with sulphate of copper
in 1846, following with chloride of mercury in 1847, and chloride of
zinc in 1852, going back to chloride of mercury, and again to chloride
of zinc, using the latter until 1865, then using creosote to protect the
piles against the _teredo_ at Taunton Great River (experiment No. 2.
creosoting), he has had millions of feet of timber and lumber prepared
by the various processes, and has kindly placed at our disposal many
original reports in manuscript and pamphlets which are now very rare.

Experiment No. 6 was made by Mr. Ashbel Welch, former President of this
Society, and consisted in boring hemlock track sills 6 x 12 with a 1-1/8
inch auger-hole 10 inches deep every 15 inches. These were filled with
common salt and plugged up, as is not infrequently done in
ship-building, but while the life of the timber was somewhat lengthened,
it was concluded that the process did not pay.

Salt has been experimented with numberless times. It is cheap, but is a
comparatively weak antiseptic, its atomic weight being 58.8 in the
hydrogen scale, as against 135.5 for chloride of mercury.

Experiment No. 9 is included in order to notice the well-known and most
ancient process of charring the outside of timber. In this particular
case, the fence posts after charring were dipped for about three feet
into a hot mixture of raw linseed oil and pulverized charcoal, which
probably acted by closing the sap cells against the intrusion of
moisture, which, as is well known, much hastens decay. The posts, which
had been set butt-end upward, were mostly sound in 1879, after 24 years'
exposure.

Experiments Nos. 41, 42, 43, and 44 did not, however, result as well,
and numberless failures throughout the country attest that charring is
uncertain and di