DOMESTIC LIFE 



entangled in fishing-nets at a depth of 180 ft. and 

 that their descent to a depth of 90 ft. is quite 

 authentic, so that perhaps the depth of this pen- 

 guin's dive was not an unusual one. 



The tide at the open water leads where they 

 bathed ran a good six knots, but the Adelies swam 

 quite easily against this without leaving the surface. 



In the water, as on the land, they have two means 

 of progression. The first is by swimming as a duck 

 swims, excepting that they lie much lower in the 

 water than a duck does, the top of the back being 

 submerged, so that the neck sticks up out of the 

 water. As their feet are very slightly webbed, they 

 have not the advantages that a duck or gull has 

 when swimming in this way, but supplement their 

 foot-work by short quick strokes of their flippers. 

 This they are easily able to do, owing to the depth 

 to which the breast sinks in the water. 



The second method is by "porpoising." 



This consists in swimming under water, using 

 the wings or " flippers " for propulsion, the action of 

 these limbs being practically the same as they would 

 be in flying. As their wings are beautifully shaped 

 for swimming, and their pectoral muscles extraor- 

 dinarily powerful, they attain great speed, besides 

 which they are as nimble as fish, being able com- 



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