Popular Educator. VOLUME THE THIRD. ROYS MECHANICS ISTITU STUDIES serve for delight, for ornament, and for ability. Their chief use for delight, is in privateness and retiring; Presentect by Hu When MC Savil CASSELL, PETTER, AND GALPIN, LA BELLE SAUVAGE YARD, LUDGATE HILL, E. C. TO OUR READER S. LOOKING back upon the past half-year of our labours in endeavouring to educate the people, we cannot but congratulate our readers on the increasing evidence we have received from them, that our system of National Education has been eminently successful. By means of our Journal, hundreds have been led to study a variety of useful branches of learning and knowledge, of which beforehand they had not the remotest idea; and though coming to this study under the most disadvantageous circumstances, many have made a degree of progress in these branches which not only surprises themselves, but astonishes and delights us; and encourages us to go on in our labour of love, believing that we shall ultimately receive our reward. The new branches of knowledge which are to be brought before our readers in the next Volume of THE POPULAR EDUCATOR will be found in the last page of the last Number of this Volume; and we trust that the same success which has attended our past labours will accompany our present endeavours to impart a knowledge of them to our readers; and that we shall have hundreds of diligent students of Chemistry and Natural Philosophy, who, though they may not rival Davy and Newton, yet may acquire a respectable proficiency in this department of learning, and one which will be of lasting avail to them through life. The Mathematics and the Languages will, of course, still form an important part of our series of Popular Instructions; nor will Biography and Mental and Moral Philosophy be omitted, as soon as ever we can find a place for them. Geography, Instrumental Arithmetic, and various other branches begun in this Volume, shall be continued in the next Volume; but whether our Lessons shall relate to former or to new branches of knowledge, every means shall be employed to convey the greatest possible amount of information in the least possible amount of space, and in the shortest possible time; and we hope that our readers will give us credit for being the best judges of these necessary lements in the great work which we have undertaken. LVIII. Qualification; Table of Adverbs KEY TO THE LATIN EXERCISES. Lessons XXXIV. to XXXV. LVII. Conjugations of Verbs 191 200 ANSWERS TO CORRESPONDENTS. Government Stock, Solution of "Lean Horse" Query, the Cube of a Residual, &c., 28. Arithmetical Questions solved, Plants for a Bower, &c., 44. Solutions of Arithmetical Questions, 60. Prices of Globes, Solution of Query, &c., 76. On Eloquence, Exponentials, Ship Query, Solution of a Cubic Equation, &c., 120. Arithmetical Question, 148. Order of Mathematical Studies, Arithmetical, LIX., LX. Idiom; Collocation of Words ...................................... 214, 234 Algebraical, and Geometrical Queries, 164. Difference between Lessons XXXII. to XXXIII........................ 58 the Aristotelian and Platonic Philosophy, Cause of the Tide, Prices of Electrical Machines and Batteries, 180. Analytical Table of the Bible, 196. Mutual Instruction Societies, Meaning of 86 Baptizo, 256. Lines on Winter, Inland Book Post, 300. Answer 269 to the Query on the Creation of Light, 316. Arithmetical Query, 314 344. Chemical Constituents of the Potato, 360. 357 The Demulation of Rocks in Saaca Switzeriand. In a former lesson, I intimated that the formation of valleys was a difficult problem in geology. It is evident that rivers, In general, have not excavated their own beds, but flow in valleys which have been formed, for the most part, by other agents. In the majority of instances, rivers are filling up, VOL. III. | produced in the strata of the earth's crust, either when tracting, or when suddenly elevated from the bed of the ocean. They are longitudinal, following the direction of the mountain chain; or they are transverse, running across that direction Their sides are generally rugged, mostly steep, and their edge 53 |