1005 
In one of the sections a nodule of manganese was found to be 
cut through. The concentration of the manganese ore appears to 
be perfect in this clay since not a trace of scattered grains of 
manganese has been found in any of the sections of the red clay 
in the slide. 
Besides the fragment of quartz mentioned sub f visible under 
the microscope, I also observed with the naked eye some white points 
which proved to be composed of diminutive pieces of quartz. These 
fragments of quartz I consider to be erratic in the red clay, i. e. 
to be constituents of terrigenous origin, which for some accidental 
reason or Other have been deposited in the deep sea; they may 
have been transported by floating treetrunks outside the littoral zone. 
For Timor and the East-Indian Archipelago in general such an 
interpretation is admissible, because also in the Mesozoicum this region 
cannot at any time have been far remote from land. 
b. The manganese nodules. 
Jonker collected a large number of manganese nodules from the 
deep-sea clay of Noil Tobee. The largest among them have the size 
of lemons, the smallest are about equal in size to nuts; in the 
fragments of red clay a good many occur no larger than peas. The 
largest specimen measures 10 X 85 X 6 cm. Two types are found 
in the collection, the first type being represented by 90 specimens, 
the second by 2 speeimens only. 
Type 1. Nearly all nodules are spherical or ellipsoidal. A few 
are cylindrical in shape and evidently originated by the coalescence 
of two individuals. 
The surface is tubercular and finely granulated, reminding one 
of shagreen (PI. II, fig. 4). The colour is black to brownish black; 
the stripe is dark brown. The nodules are mostly dull, but display 
a faint metallic lustre on the projecting parts of the relief, i.e. on 
the granules and on the tubercles. Their hardness is less than 2. 
The specific weight is + 1.7. This low value is due to the great 
porosity of the nodules. As to physical properties the composing 
material is analogous to Waad. 
The manganese nodules possess a distinctly concentric structure. 
A radial arrangement could hardly be perceived in some, in others not 
at all. Several nodules in the collection were broken in two, and 
show very well the concentric structure. (Plate II fig. 1 and 2). Some 
of them are broken on purpose, but Jonker reports that just 
below the surface he often found the nodules broken in two 
