Royal Institution . 313 



metic, for example, a system of rules is placed before the pupil, and 

 he is told to do a certain number of sums by those rules. When the 

 boy has succeeded in doing so he receives praise, and believes he has 

 done all that is necessary, whereas he has scarcely done anything. 

 He sees not the principle on which the rule is founded. His reason- 

 ing powers have scarcely been called into exercise. His memory is 

 thus burdened with a load of rules without one connecting principle. 

 It is a very common observation with a boy, when he cannot solve a 

 question in arithmetic, that he has forgot the rule. Had he got prin- 

 ciples instead of rules, arithmetic would have become as it were a part 

 of himself. He could no more forget these principles than he could 

 forget his own name. 



When a boy has obtained an accurate view of the great leading 

 principles of arithmetic, which may be attained in a few months, he 

 should be gradually led on to geometry. The ordinary mode of 

 teaching geometry in schools is to place the Elements of Euclid in his 

 hands. Now this Work, notwithstanding its many excellencies, is 

 not well adapted to the instruction of boys. The demonstrations are 

 too verbose and perhaps too formal for youth j and the arrangement, 

 however logical, is not the arrangement according to increasing diffi- 

 culty of solution, which ought to be the arrangement for instruction : 

 besides, it is entirely synthetical. Reading Euclid, as it is called, may 

 improve the memory, and give a sort of mathematical precision to the 

 language, but it certainly does not bring into play the reasoning and 

 inventive faculties of youth. The analytical mode constantly employs 

 the reasoning powers, and is the only mode which can rouse the dor- 

 mant inventive powers of youth. 



Boys are always anxious to see the use of what they learn. Now 

 this may be done from the very commencement of their geometrical 

 studies. Let them be taken out to the fields and shown the applica- 

 tions by taking the angles subtended by distant objects, which may 

 be accomplished by means of very simple instruments that can be 

 made for a few shillings. By taking a few angles, and measuring, by 

 means of a tape or chain, a few lines, the boys would be delighted to 

 construct the figure by means of their protractor and diagonal scales, 

 and thus to ascertain by measurement the distances of remote ob- 

 jects, &c. 



By pursuing this plan, Dr. Ritchie stated, he found that he could 

 interest boys in their mathematical studies from the very commence- 

 ment, and having done so, their progress must keep pace with the in- 

 terest thus excited. 



The whole discourse was illustrated by numerous striking ex- 

 amples. 



Feb. 22.— Mr. Faraday on the Practical Prevention of Dry Rot. In 

 order to preserve timber from the destructive ravages of dry rot and 

 other species of decay, a gentleman (Mr. Kyan) has proposed and 

 practised the application of a solution of corrosive sublimate. A so- 

 lution in the proportion of a pound of this substance, (cost about 

 three shillings,) in five gallons of water is prepared, and the timber 

 immersed in it for a week. A load of fifty cubical feet is found to 

 Third Series. Vol. 2. No. 10. April 1833. 2 S 



