178 FRAGMENTS OF SCIENCE 



strait, Mr. Busk informs me, has undergone similar 

 disturbances. ' 



In the harbor of Gibraltar, on the morning of our de- 

 parture, I resumed a series of observations on the color 

 of the sea. On the way out a number of specimens had 

 been collected, with a view to subsequent examination. 

 But the bottles were claret bottles, of doubtful purity. 

 At Gibraltar, therefore, I purchased fifteen white glass 

 bottles, with ground glass stoppers, and at Cadiz, thanks 

 to the friendly guidance' of Mr. Cameron, I secured a 

 dozen more. These seven- and- twenty bottles were filled 

 with water, taken at different places between Oran and 

 Spithead. 



And here let me express my warmest acknowledg- 

 ments to Captain Henderson, the commander of H.M.S. 

 "Urgent," who aided me in my observations in every 

 possible way. Indeed, my thanks are due to all the offi- 

 cers for their unfailing courtesy and help. The captain 

 placed at my disposal his own coxswain, an intelligent 

 fellow named Thorogood, who skilfully attached a cord 

 to each bottle, weighted it with lead, cast it into the sea, 

 and, after three successive rinsings, filled it under my 

 own eyes. The contact of jugs, buckets, or other vessels 

 was thus avoided; and even the necessity of pouring out 

 the water, afterward, through the dirty London air. 



The mode of examination applied to these bottles has 

 been already described. 2 The liquid is illuminated by a 



1 No one can rise from the perusal of Mr. Busk's paper without a feeling 

 of admiration for the principal discoverer and indefatigable explorer of the 

 Gibraltar caves, the late Captain Frederick Brome. 



8 "Floating Matter of the Air," Art. "Dust and Disease." 



