Page:Transactions and Proceedings of the New Zealand Institute - Volume 1 (2nd ed.).djvu/475

Rh used for steam coasting purposes. There were also thin seams of a true black coal, associated with sandstone, abounding in mesozoic fossils. The mineral waters from the geysers in the Bay of Plenty had also been analyzed. Dr. Hector stated that there was now sufficient evidence to prove that the hot springs at Rotorua were produced by the contact of fresh water with hot rocks; while the springs at White Island were entirely different, owing to their being dependent upon the access of salt water. Dr. Hector also explained that the source of heat at these different localities, some sixty miles apart, might be in some way connected, and that the character of the salts contained in thermal waters depends on local circumstances. These chemical investigations had been made in continuation of a paper communicated to the Auckland Society. A few metallic ores had been added to those previously known. Further, that Mr. Skey in the course of some recent investigations had discovered a new process for desilvering argentiferous gold, such as that found at the Thames Gold Melds. The processes at present in use for separating the silver from the gold are costly and tedious, but Mr. Skey had found that an addition of bichromate of potass (in the proportion of five parts to every three of silver contained in the argentiferous gold) to the ordinary melting pot will remove the silver, along with all traces of iron and copper contained in the gold. The process is being tried on a larger scale on the Thames, by the assayers to the Banks; and Mr. Henry Severn, the chief assayer to the Union Bank, who is at present inspecting the Thames Gold Field, has undertaken to report as to the practical utility of the process, the great advantages of which will be obvious to all metallurgists. The pressure of business for the evening prevented the reading of Mr. Skey's paper on the subject.

1. "On the Measurement of Dinornis Bones," by Dr. J. Haast, F.R.S. (Transactions, p. 21.)

In the absence of Dr. Haast, the principal portions of the paper were read by Dr. Hector, matters of detail being omitted.

Mr. Mantell wished to know how it was possible to determine, otherwise than by means of the crania, whether the number of bones taken out of a confused heap belonged to Dinornis or Palapteryx.

Dr. Hector said that Dr. Haast must have had great difficulty in determining the different varieties from the data at his command. It was hard to see how Professor Owen himself could assign a single bone to a different variety or even to a different genus. Dr. Haast appeared to have been guided almost entirely by proportional dimensions, and in that respect he had followed the example of Professor Owen. Disregarding mere difference of size, without accompanying differences in proportion, there appeared to be five different kinds; but the specimens of bones on the table would show