When and where the most important of discoveries, that of fire, was made, it is impossible to say. Fire arising from natural causes, such as conflagrations started by lightning, no doubt early taught man the advantage of this agency as a protection from cold, but the artificial production of fire was a process too intricate to be arrived at by undeveloped man except as a result of accident. It has never been achieved, as we have seen, by the Andaman Mincopies. The rudiments of the fire-making art were possessed by primitive man. In chipping flints into arrow or lance heads sparks must frequently have been struck from the hard stone, and at times these may have fallen upon and kindled inflammable material. The rubbing requisite in shaping and polishing war clubs may have yielded a heat occasionally causing fire. In boring the holes necessary to make the needles found among primitive implements, a process resembling that of the fire-drill must have been employed. In short, it is not difficult to conceive of more than one way in which the fire-making art could have been gained by accident, though it may have been late in coming, since some, perhaps all, of the arts described were not attained until the Glacial Age. Once possessed, this important art would scarcely have been suffered to disappear. With its aid man could defy the effects of the glacial chill, so far as its direct action upon his body was concerned; and with it he also gained a new and efficient means of defence against carnivorous animals, which have ever since feared fire more than weapons.