THE NETHERLANDS AND BELGIUM. 143 
The Boarding-School at Carlsbourg, under the management of 
the Christian Brethren, made a more comprehensive exhibition, 
various aids for teaching, and specimens by the pupils, havingbeen 
so arranged as to give a very good insight into the working of the 
institution. The aids for teaching descriptive geometry, exeeuted 
by J. J. Piron, the director of the school, formed the most promi 
nent feature of this exhibition. The course of instruction was 
systematically illustrated by means of large wall-charts; while 
exceedingly well-executed models in cardboard, showing the con- 
struction-lines, and accompanied by their projeetions, gave a still 
clearer idea of it. These models were among the simplest, and at 
the same time the most practical for their purpose, that were to be 
seen in the Exhibition ; besides their eonvenience and their cheap- 
ness, they offer an advantage over other models, as the three 
planes are movable, so that, by laying them down, a very clear 
insight can be given into the representation of the projection. It 
is said that these models are to be published by the government, 
which would certainly be in the interest of education. 
The specimens by the pupils of the school were especially praise- 
worthy in linear drawing ; and it appears that descriptive geometry 
is cultivated in the institution, in preference to other subjects. 
Of other aids for teaching, we must mention Stroesser’s wire- 
models for instruction in stereometry, trigonometry, and crystal- 
lography. Their practical character is everywhere known, and 
they have frequently been favorably spoken of by specialists, even 
in the papers. In the mathematical bodies, the distinction which 
is marked by color between the ground-form, and the transforma- 
tion of the figure, is very instructive, and aids the understanding 
materially. For class-instruction, however, they appear to be 
too small. Their maker also exhibited models of wood, and 
apparatus for perspective. 
F. Licot, Director of the Drawing and Modelling School at 
Nivelles, submitted a “ Course of Linear Drawing by Sight, Based 
on Geometry,” in which the elements of form are practiced in con- 
junction with freehand drawing, which is followed up bj- projec 
tion and ornament-drawing. The author continues to combine the 
elements of freehand with those of linear drawing, where in 
reality the division already sets in of itself, and in his work gives