These lectures were delivered with the assistance merely of a few notes, the author in preparing them for the press adhering as nearly as possible to the shorthand writer's manuscript. They must be read as intentionally untechnical holiday lectures intended for juveniles. But as the print cannot convey the experiments or the demonstrations, the reader is begged to make the necessary allowance.

The author desires to take this opportunity of expressing his thanks to Messrs. Bryant and May; to Messrs. Woodhouse and Rawson, electrical engineers; to Mr. Woolf, the lead-pencil manufacturer; and to Mr. Gardiner, for numerous specimens with which the lectures were illustrated.

THE STORY OF A TINDER-BOX