September 11, 1896.] 



SCIENCE. 



359 



that it was a casual visitor who detected it, so 

 that to this visitor, and not to the Lick staff, be- 

 longs the discovery. What such an outsider's 

 discovery betokens about the efficiency of the 

 staff it is not our purpose to remark. The 

 value of our observations consisted in their 

 great numbers, in the fact that depressions were 

 seen for the first time, in the systematic search 

 made for them all around the planet and in the 

 information they have yielded in regard to its 

 meteorology and topography. Of Prof. Camp- 

 bell's attempt to criticise the discussion of these 

 observations it is useless to speak, as, owing to 

 his ignorance of the original data, his guesses 

 on the subject are not important. 



7. The Lick article asserts that the vegeta- 

 tion theory was suggested by Schiaparelli. If 

 "the writer will read, once more, our translation 

 of Schiaparelli he will see that such is not the 

 case, and that not only is Schiaparelli speaking 

 solely of the canals, but that he rejects the 

 mere suggestion of vegetation, nor does he hold 

 it to-day. Nor is this all, for Prof W. H. 

 Pickering suggested the same theory many 

 years before. 



8. The attempt to disparage Mr. Lowell's dis- 

 covery that the Martian longitudes came to the 

 meridian twenty minutes behind time, by at- 

 tributing it to Prof. Keeler, will be seen to be 

 an error, by any one who cares to consult the 

 original papers of both. 



9. As to any knowledge at the Lick Observa- 

 tory of a Martian atmosphere, it has been 

 purely negative, Prof. Holden going so far in 

 an article, in the North American Review for 

 1895, entitled ' Mistakes about Mars ' as to de- 

 clare that the opposition of 1894 would be 

 memorable for having proved an absence of at- 

 mosphere. "We may let Holden' s Mistakes 

 about Mars speak for themselves. 



"We could go on in this manner, but we have 

 shown enough. "We should not have noticed an 

 article like the one before us had it not been an 

 attempt on the rights of property, rights at least 

 as sacred in intellectual matters as in those more 

 jnaterial ones which the laws protect. 



A. E. Douglass, 

 For the Observatory. 

 Lowell Obseevatoey, Flagstaff, Arizona, 

 August 14, 1896. 



commercial mica in north CAROLINA : THE 

 STORY OF ITS DISCOVERY. 



In an interesting and instructive article on 

 Mica and Mica Mining, published in the Pop- 

 ular Science Moiithly, for September, 1892 

 (Vol. XLL, p. 652), C. Hanford Henderson 

 makes the following statement concerning the 

 discovery of commercial mica in North Caro- 

 lina : 



" The location of the mines has been largely 

 accidental. So far as I have been able to learn, 

 the first one opened was the Sinkhole Mine in 

 Mitchell county. The spot was marked by the 

 existence of trenches, many hundred feet long 

 in the aggregate, and in places fully twenty 

 feet deep. Large trees growing on the debris 

 indicated that the workings were very ancient. 

 It was supposed that they had been for silver ; 

 and when the trenches were re-opened, at the 

 close of the war, the search was for that metal 

 and not for mica. Silver seems to dominate in 

 the Carolinian dream of mineral wealth, when 

 it is, of all such dreams, the one least likely to 

 be realized. The search for silver being unsuc- 

 cessful, the mines were again abandoned. The 

 mica that had been thrown out was left on the 

 dump, and soon advertised the real character of 

 the mine. A stock driver, passing that way, 

 carried a block of it to Knoxville, where it at- 

 tracted the attention of men acquainted with 

 its value. They investigated the matter, emi- 

 grated at once to Mitchell county and began 

 systematic mining for mica. As the mineral 

 was then selling for from eight to eleven dollars 

 a pound, the rewards were considerable, and 

 much enterprise was shown in the development 

 of the industry. ' ' 



This statement was also published in the 

 Engineering and Mining Journal, for January 7, 

 1893 (Vol. LV., p. 4), as a part of an abstract 

 of the above paper. 



During the summer of 1880, as the assistant 

 of the late Prof W. C. Kerr, State Geolo- 

 gist of North Carolina, and in the capacity of a 

 special agent of the Tenth Census, I visited the 

 various mica localities of the State, for the pur- 

 pose of securing statistics an.d such other in- 

 formation as was deemed necessary in making 

 up his report. "While in Bakersville I made 

 careful inquiry concerning the origin of the 



