138 
On th # Physalia pelagica. 
tlic power of contracting each set separately, as it may 
require to spread more or less surface to the breeze, and 
thus makes them act like reefs in a sail; and when the 
whole of them are contracted together, the bladder just 
appears above the surface of the water. Sometimes the 
smallest end is raised out of the water, at other times it 
turns to one side or the other, with its crest erect, to 
veer about as it sails along; and thus, with the tentacula 
hanging below to act as a rudder, and the crest above, 
with more or less surface spread to the wind, the animal 
can imitate most of the manoeuvres of a ship. 
All these evolutions may be seen when the animal is 
placed in a large tub of water, but it cannot be preserved 
long alive; for, in less than twenty-four hours after it has 
been taken, the tentacula and softer parts begin to 
deliquesce or dissolve in the water, and at last it remains 
motionless on its surface. Care must be taken in touch¬ 
ing the tentacula, for they sting very sharply, and even 
the water they have been placed in will do the same. 
Two boys, employed to wash out the tubs in which I had 
kept some for two days, were so severely stung as to have 
Erythema produced on the hands and forearms ; but, by 
applying cotton wool to the one case, and a spirit lotion 
to the other, the pain and inflammation ceased in less 
than twelve hours. The stinging matter seems inert 
when dry; for I have purposely tried it by laying the 
recent tentacula on a cloth and drying it, which, when 
rubbed on the dry skin, had no effect, but when applied 
to any moistened part, even as long as a fortnight after¬ 
wards, stung nearly, if not quite as sharply, as during 
the life of the animal. 
