Rutherford's (1871-1937) experience was crucial to determine the atomic structure. This experience served to reject the previous Thomson's model, who assumed that both the positive and negative charge were uniformly distributed all over the volume of the atom. This model was inconsistent with the high values of the field needed to produce the large deviations observed in the alpha-particles bombarding a thin Au target. From his observations Rutherford suggested that the positive charge would be concentrated in a very small region, with a radius about 1/10000 the radius of the atom. This concentration of charge can account for the large deviations (up to 180 degrees) of the projectiles.