36 



THE GEOLOGIST. 



and Geoffroy St. Hilaire, and the Honorary Curator of the Museum of 

 the Ethnological Society of London. Our space will not permit us to do 

 more than record the fact, with the tribute of our admiration for the 

 talents and labours of the deceased, and the expression of our conscious- 

 ness that a school of scientific thought was founded by him which will sur- 

 vive when his faults and failings shall have "been all forgotten. 



Deep Gold Diggings or Melboubne. — As the opinions, expressed by 

 Sir Roderick Murchison (' Siluria,' 3rd edit. p. 488), that wherever the 

 veinstones in the solid rock have not been ground down by denudation, 

 and remain as testimonials of the original seat of the gold, the portions 

 which have as yet proved to be the richest are those which are at or 

 nearest the surface, have been recently seemingly impugned by the ac- 

 counts which have reached us respecting the deep quartz gold mines in 

 Australia, — the following note, by Professor M'Coy, of Melbourne, gives an 

 important confirmation of the correctness of Sir Roderick's original con- 

 elusion. In a private letter, writing of the deep gold diggings of Mel- 

 bourne, he makes these comments on them : — " SirR. Murchison's theory, 

 which I have always upheld, of the ratio of gold in the quartz veins 

 diminishing with the depth, is every day getting more support. You must 

 be cautioned that so many ounces of gold, said to have been crushed from 

 so many tons of quartz from deep mines, really means, that perhaps 1000 

 tons may have been mined, and out of it 100 tons picked as rich enough 

 to be sent to the mills ; so that the richness of the deep quartz is very 

 different from what it would appear without this correction, which you 

 must always ask after before you give up your correct position, yielding 

 to the logic of supposed facts which are really capable of explanation." 



Canadian Petroleum. — The 'Canadian Journal of Art' asserts that 

 the Canadian petroleum is not derived from coal, nor is it of recent origin. 

 It says : " Petroleum was formed long before the coal, and is the result of an 

 infinite number of oil-yielding animals which swarmed in the seas of the 

 Devonian period long anterior to the coal. The decomposition of marine 

 plants may have given some oil to the rocks of Canada and the United 

 States which are saturated with this curious substance. The shale beds 

 of Colling wood furnish an answer to those who object to the infinite num- 

 ber of animals it would require to produce the oil locked up in the earth. 

 These shale beds are composed altogether of the remains of trilobites ; 

 they extend from Lake Huron to Lake Ontario, and from west and east 

 of these lakes. The oil-bearing rocks of Canada were once a vast coral 

 reef, extending from the Gulf of Mexico to Lake Superior." 



Ieon Formed by Animalcules. — In the 'Journal de l'lnstruction 

 Publique,' M. Oscar de Watterville states that in the lakes of Sweden 

 there are vast layers or banks of iron exclusively built up by animalcules. 

 The iron thus found is called " lake ore," and is distinguished according 

 to its form, into " gunpowder," " pearl," " money," or " cake " ore. These 

 iron banks are often from 10 to 200 yards in length, 5 to 10 broad, 

 and from 9 inches to a yard in thickness. In winter, the Swedish peasant, 

 who has but little to do in that season, makes a hole in the ice of a lake, 

 and with a long pole probes the bottom until he has found an iron bank ; 

 an iron sieve is then let down, and with a sort of ladle conveniently 

 fashioned for the purpose, the loose ore is shovelled into the sieve, which 

 is then hoisted up again. The ore thus extracted is of course mixed 

 up witli sand and other extraneous matters, which is got rid of by 

 washing in a cradle like that used by gold diggers. A man can turn out 

 a ton of ore per day by this process." 



