Abstract: A shoe and an apparatus for selectively extending spikes from the bottom of a shoe. The shoe has a sole having a longitudinal direction a plurality of spike apertures. The apparatus comprises a plurality of spike assemblies, each being locatable within one of the spike apertures an elongate member extending substantially parallel to the longitudinal direction of the shoe and a cyclically alternating positioner for moving the elongate member between the first and second positions. The positioner including an actuating button. Depressing the actuating button a first time causes the positioner to move the elongate member to a first position whereat the spikes are extended from the sole. Depressing the actuating button a second time causes the positioner to move the elongate member to the second position whereat the spikes are retracted into the sole.

Abstract: A shoe and an apparatus for selectively extending spikes from the bottom of a shoe. The shoe has a sole having a longitudinal direction a plurality of spike apertures. The apparatus comprises a plurality of spike assemblies, each being locatable within one of the spike apertures an elongate member extending substantially parallel to the longitudinal direction of the shoe and a cyclically alternating positioner for moving the elongate member between the first and second positions. The positioner including an actuating button. Depressing the actuating button a first time causes the positioner to move the elongate member to a first position whereat the spikes are extended from the sole. Depressing the actuating button a second time causes the positioner to move the elongate member to the second position whereat the spikes are retracted into the sole.

Abstract: A light beam such a laser beam is used to scan the surface of an egg for flaws such as pin holes, cracks, thinned shell regions, etc. The light beam is vibrated with a rocking/rotating movement to describe a closed curve such as a circle, ellipse or an ellipse so narrow that it is effectively a straight line. The utilization of such a light beam allows identification of types of flaws due to the character of the progression of light emanating from the egg. The invention includes apparatus for rotating the egg about its longitudinal axis in the path of the beam or beams. The apparatus also includes apparatus for forming the vibrating beam such as mirrors vibrated by out of phase electro-magnetic vibration or piezo electric actuators.