VARIABILITY OF RATE OF CULTURAL CHANGE 373
the cliffs between the South Foreland and Dover. Yet, already, forty
years back, sail was being driven by steam off one sea-route after another.
The China tea clippers had been put out of business by the opening of
the Suez Canal in A.D. 1869,* which had deprived them of their advan-
tage over steamships trying to compete with, them on the long voyage
round the Cape; by A.D. 1875 all routes except the Australian had been
captured by steamships;2 and in AJD. 1881 the Australian route itself
was conquered for steam by the S.S. Aberdeen with her triple expansion
engines,3 though the wool clippers went on fighting their losing battle
till the end of the decade.4 The interval between the first two world wars
saw the process of extinguishing the sailing-ship completed.5

If a lay observer's eye is not mistaken, the close of the ninth decade
of the nineteenth century, which marked the virtual end of a fifty-years-
long struggle between a rejuvenated sailing-ship and a new-fangled
steamship, also marked the end of the spurt of creative activity which
the shipwright's art had been making during those same fifty years in
both these competing lines. While the standard battleship and merchant-
ship of A.D. 1890 had no more recognizable affinity with those of AJD.
1840 than a basilisk has with an angel fish, the standard battleship and
merchantship of A.D. 1950 bore as close a resemblance to those of AJD.
1890 as the standard battleship and merchantship of AJD. 1840 had borne
to those of A.D. 1640. No doubt the sixty years AJX 1890-1950 had also
brought with them further innovations and improvements. The intro-
duction of turbine engines driven by steam generated by burning oil
instead of coal had been a change of perhaps the same order of magni-
tude as the substitution of fore-and-aft sails for lateen sails in the Modern
Western ship at the turn of the seventeenth and eighteenth centuries,6
while the invention of radio-telegraphy and the installation of the
apparatus on board ship just after the end of the First World War, and
the invention of radar and its installation after the Second World War,
were perhaps as great landmarks in the history of the Western art of
navigation as the eighteenth-century solution of the problem of calcu-
lating longitudes through the perfecting of the chronometer.7 Yet, how-
ever notable these changes might be in themselves, they looked insigni-
ficant by comparison with the swiftness and greatness of the revolution
that had been accomplished between AJD. 1840 and AJD. 1890. To a lay
observer born in AJD, 1889 and looking back in the year 1952, it seemed
clear that his own lifetime had been, in the history of shipbuilding, a
period of retardation hi the tempo of change by comparison with the
pace of the forced march during the immediately preceding half century.

If this impression was correct, then a series of alternating accelera-
tions and retardations which had begun with the acceleration circa AJD.

1 See Clowes, op. cit., p. 105; Abell, op. eft., pp. 141-2.

2 See Bassett-Lowke and Holland., op. cat., p. 182.

s See ibid., p. 182. 4 See Clowes, op. cit., p. 106.

s See Bassett-Lowke and Holland, op. cit., pp. 160-1. In The Times of the agth
January, 1951, a photograph -will be found of 'the Pamir and Passat, the last two suiting
barques to take part in the traditional grain race from Australia to England, lying at
Penarth Docks. They will be taken in tow to Antwerp for breaking up.'

fi See p. 368, n. 3, above.

f See Prestage, op. crfc, p. 324.