212 TROPIC DAYS 



which are intensely black with a pearly lustre. The 

 pretty movements of the mantle like the swinging of 

 the skirts of a well - apparelled damsel attracted 

 admiration, and on peering into the shell a glimpse of 

 something precious was obtained. 



Tossed and twirled about just below the old gold 

 fringe was a black pearl about the size of a pea. The 

 prize was safe. Without risk of loss it could be watched 

 in its unceasing revolutions. It seemed as if the animal, 

 with automatic perseverance, attempted to eject the 

 incubus, the weight of which kept it about an inch below 

 the aperture of the valves. Such motion would natur- 

 ally tend to perfection. Whatsoever its lustre, it would 

 certainly be a sphere. Besides, it was a pearl in the 

 making. As long as it remained within the pinna and 

 it could not be voluntarily rejected, its size would 

 inevitably increase. It was the rolling stone to which 

 time and the secretions of the animal would add weight 

 and, peradventure, beauty. 



Was mortal ever before privileged to watch over the 

 growth of a black pearl ? The activities of the mantle, 

 a blending of enticing colour and poetic motion, were 

 slow, free, and light-attracting. The ancients believed 

 that some pearls were constituted by flashes of light- 

 ning playing on bubbles within the oyster. A relative 

 of the family here seemed to be wooing the tropic sun 

 of its beams, if not to vitalise, at least to burnish its 

 treasure. 



Close scrutiny showed that the pearl was not abso- 

 lutely free. It was enclosed in a transparent membrane, 

 the merest film, which confined it to a particular position 

 in the mantle, while it seemed to possess independent 

 actions vertical and revolutionary. Perhaps the rays 

 of light which fell unequally on it through the water 

 created the illusion of revolutions, but it is certain that 



