Abstract: Internal combustion engine having a main combustion chamber (26) and a subsidiary combustion chamber (30) interconnected by a passageway (32) having a flow control element (34) arranged therein to cyclically vary the extent of communication provided between the main and subsidiary combustion chambers. In use a subsidiary air fuel charge is first ignited in the subsidiary combustion chamber (30) with the control element (34) substantially blocking communication between the two combustion chambers (30,26). Then the control element (34) is moved to permit the igniting air fuel charge in the subsidiary combustion chamber (30) to move through the passageway (32) to ignite a main air fuel charge in the main combustion chamber (26). The control element (34) is reciprocable having a head portion (82) which is moved from within the passageway (32), into the subsidiary combustion chamber (30) to effect opening of communication between the combustion chambers (26,30).

Abstract: Internal combustion engine wherein a main air fuel charge is ignited by first igniting a pilot air fuel charge and bringing the two charges together, the main charge being compressed before ignition to a higher compression ratio than the pilot charge.

Abstract: A heat insulated container for cold storage of articles, the container having a device therewithin for containing solid CO.sub.2. The device has a heat insulated body with an internal cavity open to a base thereof, the base resting on a lower heat conductive plate within the container such that the device can be positioned as desired in the container with a lower cavity opening facing the heat conductive plate. Solid CO.sub.2 is positioned within the cavity, resting on a member mounted therewithin and movable in the cavity to vary the spacing of the solid CO.sub.2 from the heat conductive plate, thus to vary the cooling effect of the solid CO.sub.2.