Detonation of explosives

This invention relates to a time delay element, for use in a chemical detonator, the time delay element including an assembly, in a tubular casing having open ends, of : a timer charge made of a timing composition; a sealing charge made of a pyrotechnic material at one end of the timer charge, in contact therewith and in sealing contact with the inner surface of the tubular casing; a priming charge in contact with the end of the timing charge opposite the sealing charge; and at least part of a base charge being in contact with the end of the priming charge opposite the timer charge. The invention also extends to a chemical detonator including such a time delay element, and it extends, further still, to a method of manufacturing such time delay elements.