Than what the heat of 3,600° Fahr. To fuse many metals, can be much safer for all, both in pressed wax and slate rock. J. T. 1871.] ******************** XIII. SPONTANEOUS GENERATION. XIV. SCIENCE AND THE 'SPIRITS'. ******************** VOL. II. LONDON: LONGMANS, GREEN, AND CO. 1879. All rights reserved. PREFACE TO THE SIXTH EDITION. TO AVOID unwieldiness.