[Illustration]




SCIENTIFIC AMERICAN SUPPLEMENT NO. 799




NEW YORK, APRIL 25, 1891

Scientific American Supplement. Vol. XXXI, No. 799.

Scientific American established 1845

Scientific American Supplement, $5 a year.

Scientific American and Supplement, $7 a year.


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TABLE OF CONTENTS.

I. ARCHITECTURE.--Marble and Mosaic.--By T.R. SPENCE.--A
paper recently read before the Architectural Association, London,
containing valuable suggestions for designers of buildings.

The St. Lawrence Hospital for the Insane.--A New York State