July 3, 1885.] 



SCIENCE. 



silt-laden condition had been suggested, rather than 

 an argument based on the implied converse? The 

 fact is evident, that the water on the west side is more 

 heavily laden because erosion on that side is most 

 active. This, of course, directs the search for the 

 cause of erosion in another direction than the one 

 which those who would fain persuade themselves and 

 others that the improvement of the Mississippi is pos- 

 sible by the principles and methods now employed, 

 would choose to take. 



The variations of silt-burden at the mouth of the 

 Mississippi, attributed to the influence of Missouri- 

 River water and the erosions below Cairo, have their 

 final explanation in dynamic conditions which may 

 be local. 



The quantity of material delivered by the Missouri 

 into the Mississippi may be nearly equivalent to the 

 quantity discharged by the Mississippi into the Gulf 

 for any period without establishing a presumption of 

 identity; since that quantity is small, compared with 

 the total moved, as the result of erosions of bank and 

 scour in bed, in the thirteen hundred miles between 

 the entrance of the Missouri and the Gulf. No di- 

 rect evidence has yet been obtained that any particle 

 of sand has ever traversed the thirteen hundred miles 

 without one or many rests; but there is much evi- 

 dence that transportation of sediment is by intermit- 

 tent steps, times of rest being far in excess of motion. 

 That the quantity in motion varies enormously in a 

 few miles' distance was shown by the Fulton obser- 

 vations of 1879 and 1880, and the variation in quantity 

 was clearly accounted for by observed local erosions 

 and deposits. 



Erosions and the consequent silt movement are 

 due to an excess of energy in the stream (energy is a 

 function of mass and fall or slope) beyond that ne- 

 cessary to overcome bed-resistances, mostly friction. 

 The excess must be expended where it occurs; and 

 the work done in the way of destructive action on 

 bed and bank, and in the transportation of eroded 

 materia], measures the excess. The amount of sur- 

 plus energy varies with time and place ; so, also, the 

 work done. 



To trace any instance of work to its cause is not 

 possible or necessary. Apprehension of the fact that 

 erosion and silt-transport, with the consequences, — 

 a shifting channel and uncertain elevation of surface 

 for a given volume, — are due to dynamic conditions 

 dependent upon volume of water and its absolute 

 height above sea-level, on the one hand, and the char- 

 acter of channel, its length, form, and material, on 

 the other, will be a safeguard against many errors of 

 interpretation, of which Mr. Harrod's note affords 

 two examples. Robert E. McMath. 



St. Louis, June 17. 



Korean curios. 



I enclose an extract from a letter from Lieut. G. C. 

 Foulke, U. S. navy, of the U. S. legation at Seoul, 

 Korea, in which he kindly gives more exact informa- 

 tion in reference to ray article in Science, vol. iv. p. 

 172, and also in regard to Prof. E. S. Mprse's criticism 

 on said article in Science, vol. iv. p. 270. 



George F. Kunz. 



Min Yong Ik is a blood nephew of the Queen of 

 Korea. His father gave him for adoption to Min 

 Thai Ho, who was killed in the conspiracy of Decem- 

 ber, 1884. He is stated by orientals generally to be 

 by affinity a prince, and so generally titled. The 

 present king and queen have one child, a son, — the 

 crown prince: by Korean rule, Min Yong Ik ranks 

 next to him. 



Min Yong Ik's thumb-ring is a thumb-ring : it is not 

 in tiie least like an archery thumb-guard, which 1 

 never saw an officer have or use on any occasion, nor 

 do they have or use such. Min's jade thumb-ring is 

 one of a class of articles, among which are short 

 strings of shell-beads, pieces of amber, etc., very 

 commonly owned by Korean officers, as many persons 

 use canes at home to occupy the hands to play with. 



The gold ornament Min wore was a button indicat- 

 inghisrank: it was (as it must be) attached by a black 

 silk cord to a hair frontal band. 



I have heard from many people that at Kurngang 

 San, on the east coast of Korea, were columns of 

 stone more than six times the height of a man. Some 

 said they were crystals ; but others (and one eye-wit- 

 ness) do not speak of them as such. Probably the 

 columns below the water in the sea presented that 

 appearance. Most people say there were tree-like 

 shaped stones. Kurngang San is the place spoken of 

 by Prince Min to Mr. Kunz. 



Professor Morse is quite correct in saying the social 

 customs of the country would interfere with Min's 

 bringing his wife to America. Min often said he in- 

 tended to bring her, etc. ; but his talk was peifect 

 nonsense, for he never meant it. 



An Indian paint-cup. 



While searching for Indian remains on an island 

 in the Susquehanna, I found a paint-cup which is 

 somewhat different from the ordinary. In place of a 

 water-worn pebble which has had a natural hollow 

 on one side, — and which is, I believe, the material 

 invariably used, especially in the east, — this is made 

 from a fragment of sandstone, which has been hol- 

 lowed out entirely by artificial means. Some of the 

 powdered oxide of iron still remains in the cup, and, 

 if moistened, answers very well for a coloring-matter. 

 The site where I found the cup has furnished quite a 

 number of relics, and was very probably the rendez- 

 vous of fishing-parties. Harvey B. Bashoee. 



West Fail-view, Penn. 



Premature appearance of the periodical cicada. 



The communication of Prof. Lester F. Ward on 

 this subject in Science (v. 476) will no doubt sur- 

 prise other members of the Biological society of 

 Washington as much as it did the undersigned. 



Memory of a sound after the lapse of many years is 

 untrustworthy, as a rule ; and I was unwilling to ac- 

 cept as an established fact the statement of such an 

 abnormal occurrence, which Professor Ward based 

 solely on such memory. Yet I nevertheless endeav- 

 ored to give reason for its possibility, there being a 

 vast difference between a possibility and an estab- 

 lished fact. Professor Ward then effectually weak- 

 ened his testimony by evidence of faulty memory as 

 to the season when Cicada septendecim was heard by 

 him when a boy. 



His evidence was rejected by me for that reason, 

 and for the further reason, that, upon his own ground 

 of rejecting inexpert testimony in memory of a vis- 

 ual impression as to hybrid oaks, we must reject his 

 inexpert testimony in memory of an auditory im- 

 pression as to Cicadas. I nowhere pronounced his 

 Yirginia observations 'wholly worthless,' nor the 

 occurrence ' impossible as contrary to all canons of 

 entomology.' 



Professor Ward, in his private conversation with 

 me, made no attempt to describe the notes of October 

 last, but simply affirmed his recollection of them as 

 similar to those of C. septendecim. His description in 

 Science is of one of the notes of the species, and he 

 seems to be ignorant of the fact that Cicada septen- 



