HISTORY OF HOLLOW SPARS
schooner Miranda of 1877 had a hollow boom and
bowsprit, a fact remarked upon when her boom broke
(due to a defective fitting, it was said) in her first season.
Dixon Kemp reported that Harvey made his spars by
cutting them in half and hollowing them out, thus
keeping a parallel wall thickness (boring produced a
tapering wall if the spar tapered). The halves were joined
back together with tongues and secured with iron bands.
Making reliable hollow spars was obviously a major
challenge. Construction relied to some extent on the
uncertain animal glues of the period, which had to be
applied hot and had a short working time; and when
dry they were often brittle and not resistant to moisture.
The added weight of the necessary metal reinforcement
bands to support the unreliable glue joints also reduced
the benefits. Boring a solid spar was an option but was
limited to relatively small holes or short spars, or relied
too heavily on great skill and some luck. Despite the
occasional success, hollow spars were still rare enough
to be commented upon well into the 1890s.
Better glues meant that hollowed-out spars built in
halves, shaped inside and out, started to become more
viable in the 1880s. In America John F Mumm built a
hollow boom for the sloop Shamrock in 1888, using
Jeffery’s marine glue. Albert Jeffery had introduced his
various types of marine glue in the early 1840s, and
‘No.3’ was listed as being specifically suited for “uniting
large timbers in general as masts, yards, spars, beams”.
In 1887 a complex and ingenious mast was made by
James W Mansfield of the yacht builders W K Prior &
Co, of Boston. He built a mast in two halves, hollowed& shaped; glued them together, then spiral wrapped the
whole with 4in-wide strips of burlap (jute or sisal
hessian) laid in two opposing directions along the spar
and set in glue. Once the burlap layers had set and been
sanded, he then applied two staggered layers of “strong
manila paper” over the whole, which was then
varnished. The result was a “very light” spar, that was
“fairly durable if kept varnished”; a mast built on this
system for the sandbagger Em-El-Eye weighed 90lb and
replaced one that weighed 260lb, and the boom reduced
from 40lb to 15lb.
A Danish ship’s carpenter called Henry Piepgrass
working as a yacht builder in the 1870s in New York,
built a hollow boom for the 70ft sloop Titania; his glue
was described as a mixture of “pot-cheese” half-and-half
with quick lime. This was an ancient recipe which can be
traced to the 11th century, used by iconographers, and
was also used by Captain John Crawford on spars for
two racing yachts in 1888-9; Liris (40ft class) and
Kathleen (30ft class), both designed by William Gardner.
The larger spars on Liris were not a notable success;
within three hours of her first outing the mast carried
away (due to the failure of a tubular spreader). The other
spars all “went in succession, the last on an August
cruise” and she topped it all off by losing a “heavy solid
mast of Oregon pine” at the end of the season; then as
now, some yachts just seem to shed spars. Her little sister
Kathleen fared slightly better; although the mast opened
up early in the season until the mastman could “sight
through it, using the forestay like the hairlines in a
telescope”, it and the other spars at least stood, after aMiranda of 1877
had a hollow
boom and
bowspiritJohn Harvey of
WivenhoeC/O AMERICAN YACHTS AND YACHCTING