An Ancient Bird Census in Asphaltic Petroleum 



By M. C. FREDERICK 



At Santa Monica, California, a fourteen-year-old pedestrian suddenly 

 /~% found his feet glued fast to the earth and himself slowly settling as 

 if he had struck a powerfully magnetic quicksand. He had mistaken 

 dust-covered crude petroleum for solid earth, but was rescued in time. 



The crude or natural oil is as unlike the kerosene made from it as tar is 

 unlike water. In many localities are seepages of this natural oil (which in 

 ttime hardens into asphalt and is often called liquid asphalt) that collects in 

 pools of greater or less extent. Thick, black, sticky dust blowing over these 

 pools conceals their true nature, a crust forms on top by exposure to air, and 

 they become traps for the unwary man, beast, or bird that unsuspectingly 

 gets into their relentless grasp. 



In the rainy season, water instead of dust may cover the surface, and ani- 

 mals attempting to wade in to drink never come out, but gradually sink till 

 they are out of sight. Swallows skimming the surface and touching the viscous 

 stuff are lightly held, and in the effort to extricate themselves stick at every 

 point of contact until they are bound wing and foot and their struggles cease. 

 A workman in the oil-fields counted seventy-five Swallows at one time stick- 

 ing in the oil, which they had mistaken for water. 



In the hills back of Camulos — ^made famous by 'Ramona' — a hen with a 

 large brood of chickens escaped from her coop and set out to see the world. 

 She was found on the farther side of a large tar-pool which she had nearly 

 succeeded in crossing, her body buoyed up by her outstretched wings and her 

 chickens trailing after her like the tail of a comet — aU dead. 



On large ranches where these innocent-looking but deadly springs occur, 

 one of the daily duties in the olden times was for an employee to ride over 

 the ranch and see that no stock had got into the 'brea,' or rescue such as had. 

 The young and inexperienced and the old and disabled were most likely to 

 be caught. In play or fright, when calves and colts got to running, with the 

 heedlessness of youth, they were often trapped before they realized where 

 their steps were leading them. 



Crude petroleum left along the side of a street in Berkeley for paving 

 purposes, was found next morning to have trapped fifty pocket gophers, which 

 are so seldom seen that it was thought they rarely left their holes. 



Just west of the city of Los Angeles is a tract of land about a quarter of a 

 mile square in which are a number of these tar-pools varying from a few inches 

 to several feet across, tar and gas rising from below through chimney-like 

 openings. Oil or asphalt sometimes rises in a squirrel-hole that has tapped 

 a vein. 



The asphalt hardens on exposure to air, and many old vents have become 

 hardened and ceased to flow; but in all these places a great scientific interest 



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