Vale eI ALCAN DIS: 349 
The conglomerates differ in hardness, but in most instances bear 
evidence of the action of heat in the firmness with which the frag- 
ments are cemented together. ‘They are sometimes found in close 
contact with the solid basalt, at first seeming to be imbedded in it. 
At many localities the rock will as readily break across the frag- 
ments of basalt as along the material which unites them. These rocks 
are generally stratified, though the stratified structure is often more 
distinctly seen in the distant view than on the spot. In some in- 
stances it is very minutely distinct. The strata are generally hori- 
zontal; but along the shores it is not unusual to find a large inclina- 
tion towards the sea. On Ovalau this is very apparent; also at Mali 
Point on Vanua Lebu. 
Some of the higher elevations of Vanua Lebu, consist of these con- 
glomerates. ‘The little village of Mathuata, on the north shores of 
Vanua Lebu, is overlooked by a frowning bluff two thousand to two 
thousand two hundred feet in height. Half way to its summit, a 
very steep declivity is mostly covered with foliage ; beyond, it shows a 
lofty front of naked rock. A dense forest, as usual, crowns its summit, 
and extends down some of the side valleys. This remarkable bluff, 
though having a columnar appearance in the distance, consists of a 
conglomerate prevailing along this part of the island. The resem- 
blance to basaltic columns is rendered striking by the deep furrows 
on its vertical face, caused by the rains running in rills down its 
surface. Until closely examined, I had not suspected the true nature 
of the rock. The furrows are a series of semicircular flutings two 
and a half to three feet in breadth, and six or eight inches deep. The 
same were afterwards observed at Mali Point. This conglomerate, 
though at times nearly as hard under the hammer as the solid basalt, 
is more rapidly worn away by the elements. Looking at the cliff 
afterwards, with a glass from the ship, I found that the rock might 
be distinguished from true basalt by its uneven surface. 
Any conjecture as to the relative extent of the solid igneous rocks 
and the fragmentary deposits, with our present knowledge, would 
be very hazardous. ‘The latter were met with at almost every 
point where we landed, and we generally discovered that, where 
the shore consists of conglomerate, the basalt may be reached by 
penetrating towards the interior. We have some reason to conclude 
that, like Tahiti, the fragmentary deposits are more abundant along 
the shores of the larger islands, and that the solid basalts prevail in 
the interior. We can draw no inferences regarding the other islands 
88 
