
[Read before the Wellington Philosophical Society, November, 1904.]
This earthquake was felt nearly all over the colony, from Auckland to Queenstown. Its effects were most marked in the Hawke's Bay and Wellington Districts, especially on and near the coast from Porangahau to Castlepoint, where rockfalls occurred from cliffs, and fissures were formed in the surface-crust, indicating an intensity of IX. (or nearly so) on the Rossi-Forel scale. In the area affected and in its intensity it closely resembled the earthquake of the 17th February, 1863, which proceeded from the same region of disturbance.
Memoranda or notices of the shock were received from the following places, the Roman numbers denoting the degree of intensity (in some cases only approximately):—
IX.: Castlepoint, Motuotaraia, Porangahau.
VIII.-IX.: Napier, Hastings, Te Aute, Kopua, Dannevirke, Pahiatua, Wellington.
VIII.: Woodville, Masterton, Featherston, Carterton.
VII.—VIII.: Wairoa, Palmerston North.
VII.: Gisborne, Feilding.
VI.: Opunake, Aramoho, Marton, Nelson, Blenheim, Taupo.
V.-VI.: New Plymouth, Hawera, Kaikoura, Motueka Collingwood, Wakapuaka.

V.: Greymouth, Hokitika, Westport, Christchurch.
IV.-V.: Auckland, Rotorua, Ashburton, Timaru.
IV.: Dunedin, Queenstown.
The significance of this grouping will appear from the Rossi-Forel scale, which I make no apology for quoting at length, as I believe it has never yet appeared with the absolute equivalents in any New Zealand publication. The Arabic figures express the equivalents on the absolute scale—that is, the maximum acceleration of the earth's surface in millimeters per second per second, the acceleration due to gravity being about 9,600 mm./sec.2
