259 
of Edinburgh, Session 1876 - 77 . 
care to let no iron instrument come near them, have broken them 
by rapping them .together. Then taking only the interior parts of 
these nodules I have pulverized them in a porcelain mortar. The 
magnetic particles were afterwards extracted by a magnet covered 
with paper. Now, placing these particles on a glass slide under 
the microscope, and adding the sulphate of copper solution, there 
was in a few moments a deposit of copper on several small perfect 
spherules, varying in size from the y^o to the qJq °f an * n 
diameter. I have placed some of these spherules under the micro- 
scope and now show them to the Society. It will be noticed that 
on one the copper is not deposited all over the sphere, but in 
ramified spider-like lines. On the cut surface of a meteorite, from 
Professor Sir Wyville Thomson’s collection, which I also exhibit, 
the copper is precipitated in precisely the same manner as on the 
little sphere from the manganese nodule. Besides the spherules 
on which the copper is deposited, there are others generally of a 
larger size and dark colour. These are, so far as microscopic ex- 
amination shows, quite like the particles on the mammillated outer 
surface of this Cape meteorite, also from Sir Wyville’s collection. 
These spherules have hitherto only been noticed in those deposits 
in deep water far from land, and where for many reasons we believe 
the rate of formation of deposits to be very slow. 
They occur also only in those manganese nodules which come 
from the same deep-sea clays or deposits far from land. 
The particles of native iron found in pumice-stones are not 
numerous, and never take the form of spherules so far as observed. 
Some of these particles of native iron may then come from the 
dredge. Other particles come from the pumice and the volcanic 
materials. Professor Andrews long since showed that minute par- 
ticles of native iron existed in basalt and other rocks. And lastly 
the spherules of which I have been speaking appear to have a 
cosmic origin. 
The reason, for these spherules occurring only in deposits far 
from land and in deep water, may be more apparent by reference 
to the annexed diagram, which might represent a section from 
the west coast of South America out into the Pacific 500 miles. 
Along the shores of the continent as at a we have an accumu- 
lation of river and coast detritus. At b in depths from 1400 
2 M 
VOL. IX. 
