472 



SCIENCE. 



[N. S. Vol. I. No. 17. 



160 hues. According to Konig, the dichro- 

 matic eye (green or red blind) can distin- 

 guish nearly the same number of hues, its 

 accuracy being greater than that of the 

 normal eye in certain regions. The seven 

 oolors inherited from Newton should be 

 abandoned. Physically, any three wave- 

 lengths, sufficiently separated, suffice to 

 produce all the colors; psychologically, we 

 •can distinguish about 160 hues, or, as Leo- 

 nardo da Vinci stated, there are four dis- 

 tinct colors — red, yellow, green and blue. 

 In the same paper Konig calculates that 

 about 660 degrees of intensity or brightness 

 -can be distinguished between the light that 

 is just visible and the light so intense as to 

 be blinding. 



THE KAEAKOEAM HIMALAYAS. 



In a lecture before the Imperial Institute 

 ■of London, Mr. William Conway described 

 the expedition to the Karakoram Himalayas 

 made in 1892 under the auspices of the 

 Eoyal Geographical Society, the Eoyal So- 

 •ciety, the British Associotion, and the Gov- 

 ernment of India. The party consisted of 

 the Hon. C. G. Bruce, Mr. A. D. M'Cor- 

 mack, the lecturer, and two others, with an 

 Alpine guide. The lecturer stated, accord- 

 ing to the report in the London Times, that 

 .starting from Abbottabad, they went to 

 Srinagar, the capital of Kashmir, thence by 

 the Burzil pass to Astor and Bungi, in the 

 Indus valley. The party followed the road 

 to Gilgit, and a month was then spent in ex- 

 ploring the glaciers at the head of the Bagrot 

 valley, and the great peaks in the neighbor- 

 hood of Rakipushi. Eeturning to Gilgit 

 they ascended the Hunza-Nagar valley, and 

 visited the towns. From that point two 

 long expeditions were made into the snowy 

 region to the south and southeast before 

 pushing forward to Hispar, which was at 

 the foot of the longest glacier in the world 

 outside the polar region. Dividing them- 

 selves into two parties, they made the first 



known passage of Europeans up the ISTushik 

 pass, and the first definitely recorded pas- 

 sage of the Hispar pass. The two parties 

 united at Askole, in Baltistan, and, proceed- 

 ing up the Braldo vallej', arrived at the 

 foot of the remarkable Baltoro glacier. 

 Having forced their way to the very head 

 of the glacier, they camped for two nights 

 at an altitude of 20,000 ft. The Pioneer 

 peak, which was 3,000 ft. above the camp, 

 was also climbed, thus making, it was said, 

 the highest ascent yet authentically re- 

 corded. Returning to Askole, they crossed 

 the Skoro pass to Shigar and Skardo, 

 whence they rode up the Indus valley to 

 Leh, the capital of Ladak, or Western 

 Tibet. The Zoji pass to Kashmii* was trav- 

 ersed, and the part}^ returned from Srina- 

 gar to England. 



• GENERAL. 



Professor James D. Dana died at New 

 Haven, on April 14th, at the age of eighty- 

 two years. 



The sixty-fifth meeting of the British As- 

 sociation for the Advancement of Science 

 will commence on Wednesday, the 11th of 

 September, under the presidency of Sir 

 Douglas Galton, well known for his works 

 upon sanitation, and as an adviser of the 

 Government in matters of sanitary engi- 

 neering. An invitation is issued to the 

 philosophers of England and other coun- 

 tries, by the Secretarj^, to support this 

 meeting by personal assistance and written 

 contributions. Americans who have been 

 the guests of the British Association know 

 how admirable the arrangements are for 

 the conduct of these meetings and how, by 

 invitation to the General Committee and 

 the Sectional Committees, a visitor fi-om a 

 foreign country is soon made to feel that he 

 is a part of this great scientific organism. 



At the last meeting of the Victoria Insti- 

 tute, of London, Sir George Stokes, Bart, F. 

 R. S., in the Chair, papers by Sir J. W. 



