Q. What do curved lines mean?  A. When they are bent or crooked.  Q. What are these?  A. Parallel straight lines.  Q. What does parallel mean?  A. Parallel means when they are equally distant from each other in every part.  Q. If any of you children were reading a book. that gave an account of some town which had twelve streets, and it is said that the streets were parallel, would you understand what it meant?  A. Yes; it would mean that the streets were all the same way, side by side, like the lines which we now see.  Q. What are those?  A. Diverging or converging straight lines.  Q. What is the difference between diverging and converging lines and parallel lines?  A. Diverging or converging lines are not at an equal distance from each other, in every part, but parallel lines are.  Q. What does diverge mean?  A. Diverge means when they go from each other, and they diverge at one end and converge at the other.[B] Q. What does converge mean?  A. Converge means when they come towards each other.  Q. Suppose the lines were longer, what would be the consequence?  A. Please, sir, if they were longer, they would meet together at the end they converge.  Q. What would they form by meeting together?  A. By meeting together they would form an angle.  Q. What kind of an angle?  A. An acute angle?  Q. Would they form an angle at the other end?  A. No; they would go further from each other.  Q. What is this?  A. A perpendicular line.  Q. What does perpendicular mean?  A. A line up straight, like the stem of some trees.  Q. If you look, you will see that one end of the line comes on the middle of another line; what does it form?  A. The one which we now see forms two right angles.  Q. I will make a straight line, and one end of it shall lean on another straight line, but instead of being upright like the perpendicular line, you see that it is sloping.  What does it form?  A. One side of it is an acute angle, and the other side is an obtuse angle.  Q. Which side is the obtuse angle?  A. That which is the most open.  Q. And which is the acute angle?  A. That which is the least open.  Q. What does acute mean?  A. When the angle is sharp.  Q. What does obtuse mean?  A. When the angle is less sharp than the right angle.  Q. If I were to call any one of you an acute child, would you know what I meant?  A. Yes, sir; one that looks out sharp, and tries to think, and pays attention to what is said to him; and then you would say he was an acute child.

[Footnote b:  Mr. Chambers has been good enough to call the instrument referred to, a gonograph; to that name I have no objection.]

[Footnote B:  Desire the children to hold up two fingers, keeping them apart, and they will perceive they diverge at top and converge at bottom.]

Equi-lateral Triangle.