=Advantages.=--The second of these methods, which is often called the method of proceeding from whole to parts, should, whenever possible, be followed. For instance, in a study of such a lesson as _Dickens in the Camp_, the detailed study of the various stanzas should be preceded by an introductory lesson, bringing out the leading thought of the poem, and noting the sub-topics. When, in an introductory lesson, the pupil is able to gain control of a large topic, and see the relation to it of a given number of sub-topics, he is selecting and relating the parts of the whole topic by the normal analytic-synthetic method. Moreover, in the following lessons, he is much more likely to appreciate the relation of the various sub-topics to the central topic, and the inter-relations between these various sub-topics. For this reason, in such subjects as history, literature, geography, etc., pupils are often introduced to these large divisions, or complex lesson units, and given a vague knowledge of the whole topic, the detailed study of the parts being made in subsequent lessons. =Examples.=--The following outlines will further illustrate how a series of lessons (numbered I, II, III, etc.) may thus proceed from a first study of the larger whole to a more detailed study of a number of subordinate parts. THE ST. LAWRENCE RIVER SYSTEM _I. Topic.--The St. Lawrence River:_ Position, size, extent of system, other characteristics. Importance--historical, commercial, industrial. _II. Sub-topic 1.--Importance historically:_ Open mouth to Europe; Open door to continent; Cartier, Champlain. System of lakes and rivers large and small gave lines of communication, inviting discovery and subsequent development and settlement. _III. Sub-topic 2.--Importance commercially:_ Large tracts of valuable land, timber, etc., made available. Highway--need of such between East and West. Difficulties to be overcome, canal, ships. Competition of railways, How? Classes of goods back and forth. Avenue to and from the wheat land. _IV. Sub-topic 3.--Importance industrially:_ Great commercial centres--where located and why? Water powers, elevators, manufacturing of raw materials made available in the large areas; Immigration; Fishing. STUDY OF BACTERIA _I. Topic.--Bacteria:_ What they are; relations, comparisons; other plants in same class, or those of higher orders; size, shape; where found; conditions of growth; propagation; modes of distribution; etc. _II. Sub-topic 1.--Our interest in bacteria, arising out of the injury or good they do:_ (_a_) Injury: Decay of fruits, trees, tissues, etc., diseases--diphtheria, typhoid, tuberculosis; how developed, conditions, favourable toxins. (_b_) Benefits: In soil, cheese, butter, etc.; chemical action, building new compounds and breaking up other compounds.