Abstract: The invention is concerned with systems for transferring value between electronic purses, usually in the form of IC or “Smart” cards, via the intermediary of an interface device. In order to control the flow of value between purses a hierarchical class structure is proposed. This is achieved by assigning to each purse a class which controls the conditions under which value may be transferred to and from (mainly from) a purse. Thus each purse stores in memory a representation of its own class, together with a list of those classes to which the purse can transfer value.

Abstract: The invention concerns a filter system having a plurality of individual removable filter units disposed between inlet and outlet ducts for a gas flow path to filter the gas flow. The system comprises one or more filter ports between the inlet duct (3,5) and the outlet duct (4,6) to receive removable filter units (1), a transfer port (25) co-operable with and sealable by a flask (20) for the filter units, a seal plate (14) removably located in the transfer port, means (15) for removing the seal plate, a carriage (18) movable between the transfer port and the filter port or ports, means (15) for placing filter units on or removing filter units from the carriage adjacent to the transfer port and means (8) for placing filter units on or removing filter units from the carriage adjacent to the filter port or ports. The system may be used to filter from a gas flow harmful or potentially harmful substances, e.g. particles which are radioactive, toxic or biologically active.

Abstract: Apparatus for transporting objects in succession through a measuring head. A common drive shaft provides synchronised movement of transfer apparatus, gripper apparatus and indexing apparatus. The transfer apparatus receives objects from a supply and carries the objects to the measuring head. The gripper apparatus receives the objects from the transfer apparatus and carries the objects through the measuring head. The indexing apparatus receives objects from the gripper means and conveys the objects to an outlet.

Abstract: A fencing system including a series of mesh panels which can be connected to one another by means of fastening elements of inverted U-shaped form which are driven into the ground. Each panel includes a number of vertically spaced, horizontally extending wires which are offset laterally with respect to the vertical plane containing the bulk of the horizontal and vertical wires of the mesh. One limb of the U-shaped element passes between said vertical plane and said offset wires, the other limb being on the opposite side of said plane. A gate constituted by a fence panel turned through ninety degrees is also disclosed.

Abstract: First and second chambers, each having a rotor are interconnected by a passage. The first chamber has a contoured periphery to receive articles and the passage is shaped and dimensioned to permit travel therealong only of those articles which are orientated in the first chamber with their longitudinal axes either in the direction of travel or normal to the direction of travel. Articles in other orientations are carried round the first chamber by the rotor for representation at the passage. The rotor in the second chamber permits the passage of those articles which have their longitudinal axes in the direction of travel and topples the articles having their axes normal to the direction of travel into positions in which the axes are in the direction of travel.

Abstract: A gas adsorption filter consisting of a gas inlet, a gas outlet and one or more layers of charcoal cloth, the layers of which are arranged to lie substantially parallel to the direction of the gas flow between the gas inlet and the gas outlet.