This illustration represents a troupe of clowns I once saw on the Continent. 
Each clown bore one of the numbers 1 to 9 on his body. 
After going through the usual tumbling, juggling, and other antics, they generally concluded with a few curious little numerical tricks, one of which was the rapid formation of a number of magic squares. 
It occurred to me that if clown No. 1 failed to appear (as happens in the illustration), this last item of their performance might not be so easy. 
The reader is asked to discover how these eight clowns may arrange themselves in the form of a square (one place being vacant), so that every one of the three columns, three rows, and each of the two diagonals shall add up the same. 

The vacant place may be at any part of the square, but it is No. 1 that must be absent.

See answer