Hollow versus solid
HISTORY OF HOLLOW SPARS
NATIONAL MARITIME MUSEUM, GREENWICHVanderdecken said that Fish & Morton also built a
75ft long hollow boom (in halves, hollowed and then
banded together) for the sloop Ultra (1848), and then
bored the bowsprit on America (1851) “end to end”.
Boring solid wooden spars with augurs was difficult; the
cutters could easily deviate from the centre. Cowes
boat-builder Michael Ratsey successfully bored the masts
and bowsprit of the schooner and America’s Cup
challenger Cambria in 1868. He used augurs of about
4in diameter from both ends; and another yacht (Egeria)
had the same treatment. Cambria carried away her
topmast crossing the Atlantic in 1869. Not dismayed
Ratsey made another hollow one, this time reinforced
with iron bands, with which she successfully sailed for
many years, including re-crossing the Atlantic twice.
The owner of the iron yacht Vindex, in build at
Chester in Pennsylvania in 1871, enlisted a pump maker
from nearby Wilmington. Despite taking care to align
things, the “spoon-shaped” augurs disappointingly
emerged some time later out of the side of the mast
“near the hounds”. JM Soper described a very similar
situation when boring out a hollow boom for the giant
cutter Satanita some 22 years later in 1893, the attempt
made possibly because her rival Valkyrie II, in build at
the same time, was to have a hollow boom. Auguring
was a technique employed with some success for smaller
craft, such as the 20ft 6in LOA Lulu built by Frank
Bates in Brooklyn, New York in 1873. Lulu’s mast was
said to be 39ft long, so it was no mean feat.
It wasn’t long before the most innovative British
designer of the period, John Harvey of Wivenhoe, took
up the challenge of producing hollow spars. His
Left: Cambria in
mid-Atlantic 1870
with a reinforced
hollow top mast.
She had lost her
previous topmast
on a crossing the
year beforeWeight 11.5lbComparisons with No1:No1No2No3No1Weight 21.6lbWeight 11.5lbWeight 26.2lb34 per cent smaller diameter, same weight but 74 per cent less strong than No1Same diameter and 50 per cent stronger but 128 per cent heavier than No19 per cent smaller diameter, same strength but 88 per cent heavier than No1Strength 8,500lbStrength 8,500lbStrength 2,250lbStrength 12,700lb