In 1991, two notable formations, now considered by crop circle enthusiasts to be of historic significance, appeared. One, near Barbary Castle in Wiltshire, England, was a huge equilateral triangle with a double-ringed circle, with each angle displaying a circular formation. Some called it a three dimensional tetrahedron. It was proportionately perfect.

The other, synchronistically located near the Mathematics Department at England’s Cambridge University, was a near-perfect representation of the Mandelbrot Set – a computer-generated configuration known as a fractal. It was the size of a football field. Both appeared overnight and neither could be explained by any theory that had been posited before.

Also in 1991, a highly publicized event occurred involving the British Prime Minister's country residence. This location, consisting of several dozen acres, is guarded against terrorist attack by Britain's most expert troops. It is a maximum-security zone patrolled 24-hours a day. Despite these conditions, a perfect Celtic cross design appeared in a field in front of John Major's house, one of the circles transformed into an arrow pointing directly at the residence. The media were quick to ask the Prime Minister if a serious breach of security had taken place. "No," he replied, "it was all merely the result of poor soil conditions."

Observers photograph and scientists sample, measure and analyze data year after year. Foremost among the scientific researchers is the BLT Research Team, now headquartered in Cambridge, Massachusetts. Biophysicist W.C. Levengood has examined plant and soil samples collected from all over the world by hundreds of field-researchers. The samples are taken from inside the crop formations, the surrounding crop nearby, and totally unaffected locations in the fields. Following strict scientific protocol, Levengood discovered biological changes had taken place at a cellular level within the plants located inside the mysteriously constructed circles, suggesting the involvement of microwave energy. Dr, Levengood's findings have since been published in scientific journals, and the BLT Research Team is conducting intricate studies and publishing research papers to this day.

In 1995, tests on crop formation soil samples were conducted by ADAS, a division of the English Ministry of Agriculture. Although preliminary, they showed distinct anomalies in the nitrogen/nitrate ratios, which could not be explained. There have been other scientific tests carried out by different bodies over the years, which have produced peculiar unexplained qualities. Diagrams: John Martineau

Astronomer Gerald Hawkins, former chair of the astronomy department at Boston University, found that crop circle measurements correspond to the ratios of the diatonic scale -- simple whole-number ratios that determine a scale of musical notes. He comments, "These designs demonstrate the remarkable mathematical ability of their creators." Several formations seem to illustrate four new theorems of Euclidian Geometry hinted at, but not actually present, in Euclid’s works. Crop circles demonstrate mathematical proportions similar to the Golden Mean, or Golden Section – the ratio that is present in the growth pattern of precision organisms such as shells, sunflowers and galaxies, and represented in the spatial relationship of the bones in the human body.

Certain crop circles have been known to alter the local electromagnetic field so that compasses cannot locate north; cameras, cellular phones and batteries fail to operate, and aircraft equipment fails while flying above them. There are accounts of levels of background radiation up to 300% above normal, radio frequencies falling dramatically or rising sharply within their perimeters, animals in local farms avoiding that particular area or simply acting agitated hours before one materializes.

There are only a few dozen reported eyewitness accounts of the actual moments of a crop circle’s forming. People report seeing balls of light in the sky, hearing strange sounds and seeing portions of crop suddenly flatten to the ground. Most describe an invisible force, seemingly from out of nowhere and in otherwise calm conditions, spinning the plant stalks down within seconds, usually with surprising violence, yet little damage is found in the laid crop. In Romania, one farmer says he heard a “terrible whistling sound and a wind so ferocious it tore the hat off my head and flung me to the ground.” In the Netherlands, there is a farm in Hoeven in which crop circles have appeared several times in each growing season, sometimes two or more simultaneously. The farmer’s son witnessed several circles -- simple, single designs – as they were forming. He claims to have first heard a crackling noise, and then a stationary ball of light hovering twelve feet over the field. The light faded after about 20 seconds, but not before a section of the field below corkscrewed and whooshed down into a circular pattern.