The fact was also stated, by one of the members, that the piles of the wharfs in the southern part of the city suffer much from attacks of the Teredo; while those of the northern portion are comparatively exempt. The fact was mentioned, that piles have been entirely destroyed here in six months from the time they were placed in the water.
Prof. Brewer made some remarks on the method of calculating altitudes by observation with a single barometer. He gave an account of the methods adopted by the Geological Survey for computation, in cases where there was no station barometer nearer than the bay, or the valley of the Sacramento.
Dr. Trask mentioned that the weight of the Honcut meteoric iron presented by him to the Academy, at the meeting of March 17th, 1862, was six ounces, one hundred and twenty-eight grains, troy.
Professor Whitney called attention to the curious errors in a paper published in Petermann’s Mittheilungen, 1861, page 133, which purports to be a translation into German of a portion of a work published by Mr. J. Xantus, describing his journey in Lower California. He describes a quicksilver mine of great importance as being worked at Marques; but the description which he gives of it shows that it is the New Almaden mine which, in reality, he visited, and which, by some confusion of his notes, he has located in Lower, instead of Upper California. No mercury mine is worked on the California peninsula, so far as can be ascertained. It is evident that Mr. Xantus’s notice of rich gold, lead and copper mines on the peninsula must be taken with many grains of allowance.
On motion of Dr. Ayres, it was ordered, that twenty-five copies of the second volume of the Proceedings be placed at the disposal of the Publishing Committee for distribution to learned societies, public libraries, and distinguished scientific men in the Atlantic States.
Regular Meeting, March 2d, 1863.
President in the Chair.
Present, fifteen members.