Me 
~ 
346 Real and supposed effects of igneous action. 
more resemble a sponge,) they are much lighter than any of 
the kind that I have heretofore seen. These light materials 
are very abundant about the crater, being driven about by 
the winds in every direction, The remainder of the miner- 
als are almost all from the inside of the crater, some from the 
bottom ; others from the sides and from various places with- 
in the crater. Such as they are, I forward them for your in- 
spection, and [ should like to receive your remarks upon 
the Should any of them be worth notice, I should be hap- 
py to forward more hereafter. If there are any researches that 
you would like have made, (as you will think of many things 
that do not occur tome) be so kind as to inform me what they 
are, and I will attend to them with pleasure, and send you 
the result by the first opportunity. 
The second letter is dated Oahu, June 12, 1828. Mr. 
words, such as names of places, &c. I gave you in my let- 
ter of April 25, 1825, a short account of my ‘tour through 
the interior of theisland, from Kailua tothe volcano, and from 
to the traveller the same dreary mass of java, that is to be 
seen in most parts of the island. Mouna Roa appears to be 
of the coarsest kind ; the particles varying in size from that 
of fine sand to that of massy rocks, the angles of which ap- 
ave been worn off by attrition. Some of the strata 
of Java are horizontal ; others vary in their position from that 
to an elevation of eighty degrees. They are in every shape 
that one can imagine possible ; nor can J adequately des- 
eribe the appearance of lava, so that you can form any cor- 
rect apprehensions of the picture it presents. The horizon- 
