Inconstant was a wooden full-rigged sailing ship built in 1848 at Cape Breton, Nova Scotia which later became known as "Plimmer's Ark" and played an important role in the development of Wellington, New Zealand.

The ship was sold to owners in London, England and made a voyage to Australia carrying immigrants.

On a subsequent Australian voyage, she was wrecked at Wellington, New Zealand in 1851 when she put in for water and ran aground.

After the ship was deemed too badly damaged to sail again, the hull was purchased by John Plimmer, an entrepreneur later known as "the Father of Wellington".

[2][3] John Parker, Cape Breton Ships and Men, (London: Hazell Watson & Viney, 1967) p. 75, p. 178.