62 NATURE-STUDY REVIEW . [14:2— Feb., 1918 



is to show what one knows rather than to find out what they 

 (cannot ?) stuff in for the occasion. This is shown by writing of two 

 lines of figures on the board, the top line for instance representing 

 the number of shells and the lower line respresenting the number 

 in the class recognizing io shells, n shells, etc. Each pupil is thus 

 able to see how he stands with the average, the lowest, and the 

 highest of the class. To facilitate the mechanics of these two tests 

 I have slips of printed paper with twenty lined spaces which are 

 numbered as: 



etc. 



The questions require one or two-word answers. By holding 

 the papers beside a correct copy the mistakes are soon noticed. 

 (3). Power to do. In this type of examination the questions may 

 be answered by the use of notes and text. Suppose the class has 

 studied the seeds and seedlings of the bean, squash and corn. To 

 test the power gained in this study the pupils may be given peas 

 and pea seedlings, to work out independently without suggestions. 

 It is not knowledge but the use of knowledge that is power. 

 5. The making ar.d uses of a hectograph. 



(1). Obtain a rectangular tin about an inch deep and an inch 



larger, each way, than the paper to be used. 

 (2). Measure the pan with water to see how much material 

 is needed. (3 oz. powdered gelatine, and \]/ 2 lb. 

 glycerine) to }4 pt. of water is sufficient for a hecto- 

 graph g x 1 2 inches in size. 

 (3). The proportions are 6 oz. of ground white glue to one pt. 

 of glycerine. (Gelatine may be substituted for glue. 

 It does better work but does not last as long.) 

 a. Add a little hot water to the glue and dissolve in a 

 double boiler to prevent the glue from burning. 



b. When thoroughly dissolved add the glycerine. 



c. A few drops of carbolic acid will prevent the pad from 



moulding. 



d . If too soft, melt and add more glue. 



e. If too hard, melt and add more glycerine. 



f. If there are bubbles on the surface, prick with a pin. 



