COMMUNICATIONS RECEIVED.
The Editor of the Scientific American acknowledges with much pleasure the receipt of original papers and contributions on the following subjects:
Manufacture of Porous Cups for Tyndall Grove Battery. By W. H. S.
Cylinder Condensation. By F. F. H.
Sawdust. By W. H. M.
Keely Motor. By G. R. S.
Firing. By A. P. A.
Steam Launches. By G. F. S.
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