Here's an excerpt of material I copied several years back, when this whole chemtrail thing came to my attention.
I have no links to this, as I was just starting to collect information, and didn't think about links at the time.

Take it for what it's worth to you ...

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SKY SAMPLES ANALYZED by William Thomas with Erminia Cassani VICTORIA, British Columbia, Canada, April 22, 1999 (ENS) - As unmarked tanker-type aircraft continue spraying sky-obscuring chemtrails over regions of the U.S. and Canada, this writer and American journalist Erminia Cassani have obtained laboratory tests of fully-documented samples of aerial fallout. The samples were tested by a U.S. Environmental Protection Agency (EPA) licensed facility.

The two samples were taken from aluminum-sided structures in separate states nearly a year apart after their respective owners went outside in the wake of low-flying aircraft to find dwellings and outbuildings splattered with a brown, gel-like substance.

Trained in the health sciences, Cassani carefully took samples from the second incident which occurred at 2:00 pm on November 17, 1998. The samples were taken from property directly under the flight approach path to Thomasville airport, an old airport once used for commercial flights but now used only for small planes. However, the woman whose house and property the sample substance fell upon, observed that military aircraft have recently been using this airport for "test runs" circling the immediate area and returning to the Thomasville airfield. This facility is located a 45 minutes drive from the Harrisburg International Airport in Pennsylvania.

Noting nearby military hangars filled with big helicopters, Cassani videotaped a house splattered on all sides, as well as the driveway. The reporter also interviewed a man living near the main runway who claimed that a similar goo had hit his house the previous October.

Cassani became ill with flu-like symptoms and was sick for four days after obtaining the sample. When a marine biologist at a nearby university started working with the gel material, he too immediately developed upper respiratory symptoms. The woman whose house had been struck also caught the "flu." Two weeks before Christmas 1998 she suffered a heart attack.

Coliform tests by the state Department of Health were negative. But when the university Ph.D. biologist turned his microscope to high power, he found the glass slide teeming with a protozoan life form he said was "very resilient to very cold temperatures."

The laboratory staff who eventually received our sample for a complete analysis had never seen cell cultures bloom so fast. Cell cultures normally take several days to grow; ours flowered into brilliant colors within 48 hours of being placed in petri dishes.

Exclaiming that, "It was all over the plate," the biologist who examined our first sample wanted to know where we had obtained this "bio-hazard" material. …

… Similar encounters with a gel clinging tenaciously to porches, pick-up trucks and patrol cars have been reported across the USA - from Arizona's remote Mogollon rim to Aptos and Fresno, California and North Seattle, Washington.
The most publicized incident occurred in August 1994, when gelatinous globs began raining on Oakville, Washington about 80 miles southeast of Seattle.

After local residents became sick with vertigo, lethargy and severe shortness of breath, a lab technician found human white blood cells in the sky goo. At the Washington State Department of Health, registered microbiologist Mike McDowell also discovered the sample swarming with Pseudomona flourescens and Enterobacter cloacae.

Serratia marcescens was found in yet another gel sample obtained in Idaho in late March, 1999. Often causing upper respiratory infections resulting in pneumonia, Serratia marcescens was sprayed into the New York subway system in 1953, and over Dorset, England from early 1966 to 1971 by the military in both countries. Serratia marcescens was supposedly withdrawn as a biological warfare stimulant in the 1970s when this infectious agent was deemed too hazardous for use on friendly "test populations." //...

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