92 



EEPORT — 1882. 



Mr. J. B. B. Hennessey was kind enongli to forward me some sand 

 •which was collected at his request, and with proper precautions specified 

 by him, in desert of Rajpatana, in lat. N, 27° 40' 25", long. E. 72° 43' 

 39" ; the nearest village beins: fall 13 miles distant. The examination of 

 this sand has not as yet been completed, but at present no spherical 



Fig. 2. — Iron Particle in Sahara Sand. The light parts are metallic. Enlargement, 100 : 1. 



Fig. 



3. — Metallic Iron in Sahara 

 Sand, 100:1. 



particles have been found, nor is there any appearance of metallic iron. 

 But the sand contains a comparatively large quantity of magnetic oxide 

 (O'l per cent.). This magnetic oxide, which is of undoubted terrestrial 



origin, will naturally hide any traces of me- 

 teoric dust, which could only form a small 

 percentage of the total magnetic part. 



Similar negative results were obtained 

 with some specimens of mud collected on 

 the banks of the Nile near the village of 

 Sohag (lat. 26° 33', long. E. 2^ 07'"), on the 

 occasion of the last total solar eclipse. Here 

 also a very large quantity of debris from mag- 

 netic rocks was found in the mud, hiding any 

 meteoric particles which might have been 

 there. 

 3. "We may approach the question from yet another point of view. A 

 shooting star is not an uncommon phenomenon, and on certain nights in 

 the year we often find them counted by hundreds. Each of these meteors 

 will leave traces behind in our atmosphere, for it seems hardly possible 

 that when white hot, owing to the friction with our atmosphere, part of 

 this surface should not fuse and be left behind in a finely divided state. 



