A surveying equipment support leg used with a support for supporting surveying equipment and the like is capable of mounting alternate ground engaging structures without removal of an existing foot on the leg. The position indicating member carries one or more sensors which generate signals corresponding to succeeding cross sectional contours of the item as the member is traversed along the item from a reference position to a selected other position over this item, defining the selected segment of the item. The distance image data are converted into world coordinate values by using photographing positionposture data. Limited access to the information stored in the customer databases may be provided to prevent the respective content providers from accessing personal information of the subscribers. The control compositions further include platelet analogs, or additionally include reticulocyte andor nucleated red blood cell analogs. The gear member is axially fixed to the outer member and freely rotatable with respect to the outer member and the gear member threadedly engages a threaded portion of the inner member to translate inner member along the axis.