The vast majority of zapadnokavkazskih dolmen is a so-called a tiled type. They are built of large stone blocks, four of which are mounted vertically and closed the fifth slab forming the roof of a stone box, or chamber, dolmen. The front plate is always higher than the rear, so that the roof of the dolmen tilted back. Plates are very carefully beneath-Gnagno together with special grooves and ridges.
In front of the plate dolmen has a small opening round, oval, or at least more complex form (archaeologists call it the "hole"). Sometimes used and sixth plate forming the floor dolmen chamber, but most dolmen installed directly on the ground or (please pay attention to it!) On special stones ("heel"). Multi-ton slabs that make up the dolmen, almost no processed outside, but on the inside, forming the surface of the chamber, carefully aligned, sometimes even ground.
Caucasian dolmens were built of thick sandy limestone or sandstone, rarely used for this purpose silicified and metamorphic rocks. The time of their construction VI Markovin refers to the period from 2400's to the 1300s BC.
Furduy tried to consider the dolmens as bulk acoustic cavity (Helmholtz resonators) and on this basis to find out what the resonant frequencies were calculated. The resonant frequency of the acoustic cavity depends on the maximum perimeter Is dolmen chamber is in its perimeter at the bottom near the floor. Plotting a histogram-perimeter cameras Caucasian dolmens on the basis of data from the above monograph VI Markovin, Furduy received an unexpected result.
It was found that among more than two thousand of these structures is dominated by the construction of three types. The most frequently (statistically the most reliable) are dolmens, the perimeter of the chamber which is 720 centimeters. In addition to this group are (statistically significantly less) larger buildings with perimeter cameras and 1,035 centimeters smaller perimeter of which is 472 centimeters. Resonant frequency of such chambers are respectively 23, 16 and 35 Hz.
In other words, if in some way to these dolmens (resonators) was let down by the energy, they would sound on such frequencies. These frequencies are at the lower threshold of human hearing, adhering to the subsonic range. It is known that the biological effects of low-frequency acoustic oscillations tend to adversely. Thus, filed IA Vartanian and E. Tsirul'nikova, and human exposure ultrasound, amplitude-modulated sinusoidal oscillations of frequency of 15-40 Hz, the volunteers experienced an unpleasant sensation, which they compared to drilling the skin moving over it boring beetles. The action of high-power ultrasonic beam on the animal brain is expressed in the phenomena of functional depression or temporary shutdown of the exposed areas of the brain.