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Leiden, Jan. 27 1916. 
Mathematics. — A posthumous work of Dr. P. H. Scrourw. By 
Prof. J. CARDINAAL. 
(Communicated in the meeting of January 29, 1916). 
At the moment of Dr. P. H. Scnoutn’s regretted decease four 
sections of his great treatise ““Analytical treatment of the polytopes 
regularly derived from the regular polytopes” had been inserted in 
the works of this Academy (Verhandelingen XI3 and X15). The 
fifth section failed, which was the more to be regretted, as the 
author considered it a quite essential part of his researches and 
might well hope to complete the whole work in his lifetime. 
It was to be supposed that part of this fifth section might be 
found amidst ScHourn’s papers. Happily this supposition proved to 
be true; the fifth part was found nearly complete in manuscript. 
It is true, the manuscript bore the character of a first concept and 
had to be put in final form, but the clearness and accnrateness of 
expression, so characteristic of the deceased, revealed themselves 
in this concept. The results were nearly all put down, so we can 
fairly admit, that it is Scmovre’s work that is now to be published. 
We wish to give some remarks relating to this publication. In 
