Dr. Nagy I. Zoltán szerk.: Fragmenta Mineralogica Et Palaentologica 6. 1975. (Budapest, 1975)

almost not penetrating into the soil. The smaller fragments are (as mentioned above) at most sliding on the earth' s surface and are damaging the grasscover only. Even the famous meteorite of Hoba farm, possessing a weight of 60 metric tons, penetrated only to a depth of 1, 5 metres into the soil. However, the depth of penetration of a meteorite is not depending only on its weight, that is, its mass, and not even only on the altitude from whichit is falling down, and on the incidence angle as it is strongly dependental so, on the nature of the soil. From a hard rock surface, it could be perhaps elastically repelled, andin a peaty, marshy soil it can be submerged without any vestige. We found also a relation among the radii of spherical meteorites falling with a final velocity of 60 km/s and their velocities of incidence. A table containing the corresponding results has been published on p. 59 of a book by DETRE (1939). In the present case, we know that the mass of the meteor, when it was still flying as an intact fire-ball through the atmosphere, was of about 500 kgs, which corresponds to the following radius of the sphere: r = 76,19 cm thus the diameter of the original meteor appearing above KÄahifia was about 152 centimetres. To this diameter corresponds a velocity of 750 cm/s. However, this value has been somewhat reduced at the time when the last meteorite actually hit the ground. Namely, at this moment, the mass of the meteorite which penetrated the ground was only 294 kgs, corresponding to an effective radius of r = 64 cm that is, the virtual velocity of the reduced meteorite, which still possessed a diameter of 127, 6 cm and a mass of 294 kgs, was about 720 m/s. This means that in the time of less than a second this big meteorite penetrated into its 90 m long channel in the soil and reached there a depth of 3, 5 metres below a wood-clearing covered by bushes. Such short a time is not sufficient for a body, having the velocity of an artillery projectile, for changing its direction. This circumstance is yielding also an explanation for the extremely interesting observations made by SZABÓ. ***** A shower of meteorites depassing that of Knahina was observed only once in this country. This occurred on February 3-d, 1882 in the afternoon. This time, the number of counted stone fragments in the village Mócs in Transylvania surpassed 3000; their total weight was about 300 kgs. While the meteorites of Knahina explosed near-the-ground, and certainly within the terrestrial atmosphere, those of Mócs arrived as separate fragments, that is, they are members of a real meteoric shower. This circumstance is sharply expressed in the spatial distribution of the fragments. The most glorious and most large meteoric shower ever observed on Earth has been described by Alexander HUMBOLDT who witnessed this unforgettable phenomenon, having duration of several hours, together with his friend BONPLANDj the botanist, on the neight of November 11, 1799 at Cumana in Venezuela, where many thousands of meteorites showered down during four hours (HUMBOLDT - BONPLAND 1807).