844 T'ransactions.— Geology. 
Art. XLVI.—On the Drift Beds of Wakapuaka and Port Hills, with Remarks 
on the Boulder Bank and its Formation. By W. Weuts. 
[Read before the Nelson Philosophical Society, 3rd March, 1884.] 
STRACT. 
I mave chosen this locality for my paper from its proximity to the township, 
so that members who take an interest in geological science may have no 
difficulty in visiting the district, which may tend to invite discussion on a 
future occasion, and assist in verifying, or otherwise, the conclusions I may 
have come to on the subject. 
Drift in geological language means portions of the earth’s crust removed 
by forces from one place and deposited in another, some from comparatively 
short distances and others very wide apart. These forces are of various 
kinds, the most important of which are, Fire, Water, Ice, and Wind— 
Fire exhibited in volcanic action, which is powerfully exemplified on the 
west coast of the North Island, from Mount Egmont to Wanganui. This belt 
of country is chiefly composed of pounded pumice stone, in some places many 
feet in depth, which has been erupted from volcanoes in that district and 
` drifted by wind currents all along the belt, now producing the luxuriant 
grasses which exist there for the feeding of cattle and sheep. Water, the 
next force I have noted for effecting changes on the earth’s surface, is by 
far the most important, being constant and continuous. The smallest . 
rippling stream to the largest river are daily engaged in transporting 
matter from a higher to a lower level, as instanced on a large scale—the 
Canterbury Plains, the soil of which is the degraded high lands brought 
down by the force of water to nearly sea-level. Ice glaciers you are all 
aware are forces which carry in their course large quantities of rock and 
débris and deposit them at a low level in what are called “ moraines.” 
The last noted is wind force, which drifts lighter materials, such as fine 
scoria and pumice dust in voleanie countries, in some cases for hundreds of 
miles from the mountains from which they have been erupted. 
With these preliminary remarks on -drift beds and the forces which 
occasion them, I now come to boulder drift on a small scale, seen on the 
Wakapuaka Road and Port Hills. 
This drift shows itself on what we may call a raised beach, commencing 
at the town boundary, and exposed on bare faces for several miles towards 
Wakapuaka. This beach is raised at a high angle, in some places not less 
than 45 degrees. In the clay drift on these faces we find stone boulders 
stuck through it, somewhat like plums in a pudding. These boulders are 
generally round in form and smooth in surface, showing they have been 
carried from a distance, getting their round shape and smooth surface from 
