Quite interesting.. I was able with a quick search in google to find the following interesting links
onetwoShort part from there:
QUOTE
On 11 September, 1948, the building of New York's highest skyscraper, the Empire State Building, was attacked with hundreds of birds of various species. Eyewitnesses said that the birds were slamming into windows, as if they were trying to fly away from an imminent danger. Hundreds of birds fell down on the ground dead in May of 1917 in the US town of Baton-Rouge, Louisiana. A lot of them had strange burns on their bodies. A similar incident occurred in August of 1960 on the outskirts of Capitola Beach, when numerous birds fell down dead too. Ornithologists could never determine the reason of their death.
American researcher Charles Fort wrote in his work "The Book of the Damned" that there were weird, jelly-like beings living in the Earth's atmosphere. Medusa-like creatures, Fort wrote, had stings and tentacles, which they used to hunt for birds. The existence of such creatures seemed to be unbelievable for a very long time, until American scientists developed a special substance, aerogel. The lighter-than-air gel is a substance, the state of which is represents both hard and gas condition. Researchers proposed that the flesh of the mysterious creatures could be made of a similar substance. The theory can be partly proved with an incident, which occurred on 28 December, 1958, in Florida. Detective Faustin Galegos found a strange object outside his house. The detective said that he took the object in his hands, but could not feel that he was holding it. It was a translucent ball, the size of a soccer ball, and it was practically weightless. The detective did not manage to preserve it, because it virtually melted in the air several hours later. Faustin Galegos said that he had an impression of holding an unknown dead creature in his hands.