PIERSON: Of the creatures in the rocket cylinder at Grovers Mill, I can give you no authoritative information — either as to their nature, their origin, or their purposes here on earth Of their destructive instrument I might venture some conjectural explanation. For want of a better term, I shall refer to the mysterious weapon as a heat ray. It’s all too evident that these creatures have scientific knowledge far in advance of our own. It is my guess that in some way they are able to generate an intense heat in a chamber of practically absolute nonconductivity. This intense heat they project in a parallel beam against any object they choose, by means of a polished parabolic mirror of unknown composition, much as the mirror of a lighthouse projects a beam of light. That is my conjecture of the origin of the heat ray . . .