I hope that gentlemen who have brought note-books with them will be kind enough to follow my calculations and check any error that I may make." But a good threescore note-books, pencils, and stylographic pens were out already, and hundreds of eyes were eagerly fastening their gaze on the black-board, their owners desperately anxious to detect the first slip in the demonstration.

The demonstrator drew an isosceles triangle rapidly, and without speaking filled the remainder of the board with formulae.

The almost breathless silence was broken only by the click of the chalk on the board and the scratching of pencils and pens on paper.
When he had finished he ran through the calculations aloud, and said in the most commonplace voice: "Now, gentlemen, if, as I hope, you have found my working correct, I may draw the two lines which will trisect the triangle." He drew them, and then, as calmly as though he had done nothing more than cross the much-trodden _pons asinorum_, he told two attendants to take the board down and put it in front of the platform; then, while they were lifting another on to the easel, he said: "As those who have followed me would no doubt like a little time to revise the figures, I will go on with the next problem, which will be our old friend, or enemy, the squaring of the circle." The second board was filled with diagrams and formulae as rapidly as the first.
"There is the demonstration, gentlemen," he said, as the attendants placed it beside the other in full view of everybody.

"Now, as time is shortening, I will get on with the third problem." The chalk began to click again, and the pens and pencils scratched on to the accompaniment of murmurs and whispers and occasional grunts and snorts of incredulity.

By a master-stroke of strategy Franklin Marmion had, in placing the three demonstrations of the long-supposed impossible before them in quick succession, kept the learned, but now utterly bewildered mathematicians so busy that they literally had not time to begin "the trouble" which Brenda was now actually dreading.