Abstract: A cartridge containing two liquids, includes a first elongated cylindrical housing having a first end and a second opposite end; a second elongated cylindrical housing having a first end and a second opposite end; the first and second elongated housings being connected together in a lengthwise direction thereof at the first ends thereof and being slidable relative to each other in said lengthwise direction; a first pressure stopper fitted at the second end of the first elongated housing, the first pressure stopper having a central weakened zone which may be crossed when the cartridge is closed; a second pressure stopper fitted at the second end of the second elongated housing, the second pressure stopper having a central weakened zone which may be crossed when the cartridge is closed; a longitudinal needle with thin walls and a sharpened end, provided at the first end of the first elongated housing; a tearable membrane fitted to the first half of the second elongated housing adjacent the end of the needle; an