Ships fastenings get the short end of the recording time in
most archaeological projects. The lack
of recording data on these pieces of material culture for the Chesapeake region
have caused both misinformation as well as a perpetuation of low to no recording
for sites. We lose out on understanding
the work history and general construction of the ship if they are not recorded.
Treenails are the most common large fastenings recovered
from archaeological contexts as well as loose ship finds. Treenails fall into three general types:
Drawknife sided, compressed sided, or machine made. Drawknife sided treenails are the most common
found from Chesapeake contexts (Fig 1, A).
They are the simplest to make, and were often made from scrap wood not
large enough for framing, planking, and ceiling. They are made by taking a piece of scrap
wood, often white oak or hickory, which is then drawknifed with 7-11
sides. Diameter ranges from 25-37 mm are
common. Length can be upwards of 30
cm. Compressed sided treenails are the
next most common type observed in the Chesapeake region (Fig 1, B). These treenails are often made from scrap
pieces of work found in the building yard much the same as the drawknifed
ones. These treenails are made by forcing
scrap wood through an iron or steel die plate with a pre-formed hole. This shears off excess from the premade treenail,
but also compresses the fiber of the wood along the long axis of the
treenail. Often times these treenails
were fitted and hammered home in the direction in which they are drawn out of
the die plate. This causes the fibers to
expand if the treenail is disturbed in its fastening hole. Sizes are often the same as for drawknifed
treenails. The least common of the treenails observed in the Chesapeake are the
machine made treenails (Fig 1, C). These
are turned upon a lathe and made round and true with a graver chisel. These fastenings have not been observed by
the author often and would appear to be far more common after 1870. They are often much smaller being 15-25 mm in
diameter and shorter.
Fig. 1
Treenails as fastenings used on the external portions of ships
hulls have the virtues of they do not corrode like metal fastenings, hold firm
but are fibrous and have tensile flexibility, and are repairable if they become
damaged. As mentioned in my previous
blog post, colonial vessels of the Chesapeake region were launched quickly, English
vessels, especially English military vessels, had a tendency to sit on the
stocks being built for years, often their treenails had to be repaired even
before they entered the water. Treenails
found on colonial built vessels from Virginia and Maryland have a tendency to
be unmodified, that is that the head of the treenail has been hammered home
after being nearly cut flush. This can
be seen in Figure 2 top left. As colonial vessels of the Chesapeake were
launched quickly, no shrinkage of the treenail and planking occurred before the
wood swelled upon entering the water for service. Often treenails became damaged when their
entire head portion which held fast the outer planking would be compressed
nearly evenly on all sides. This was
often caused by a great deal of stress and the treenail would be pulled from
its framing hole. The ships carpenter
upon careening the boat would fix this by drilling a hole through the center of
the treenail all the way to the frame interface and would stuff caulking in
this hole before hammering a square peg, often made of cedar 10-20 cm. deep to
expand the treenail in the frame and form an new head as can be seen in Fig. 2
top center. Another way that a badly damaged
treenail could be repaired during the 18th and 19th
century if its head was intact but it had been pulled from its frame would be
to extract it partially and bisect it with a broad axe, pack it full of oakum
and caulking and hammer it back home smartly into its frame. This can be seen in Fig. 2 upper right. Military vessels are built “stiff” and they
don’t incur the hull stresses that commercial vessels often due under the
burden of heavy cargo. Fast sailing
vessels such as racing yachts are the same.
They however incur fore aft stresses as they sail which compresses the
head of treenails along the hull in one direction. One way to repair this is to drive a
rectangular wedge in to spread the head out of the damaged treenail as can be seen
in Fig. 2 bottom left. The worst of
damaged treenails have two options in being repaired. Firstly a second treenail could be placed diagonally
through the original forming a double treenail.
Or as colonists in the Chesapeake did not have access to drydocks but
crude careening yards only, the treenail would often be extracted, bisected and
oakum caulking and a square plug added and the treenail driven home smartly as
seen in Fig. 2 bottom right.
Fig. 2
While this is not exhaustive it shows many of the ways ships
carpenters in the Chesapeake remedied problems with wooden fastenings during
the 18th and 19th centuries. Hopefully this blog post will draw attention
to record these features. I will write
another post soon drawing on my knowledge of iron fastenings on 18th
century ships and boats of the Chesapeake.
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