THE 



SCIENTIFIC PROCEEDINGS 



OP THE 



ROYAL DUBLIN SOCIETY. 



Vol. X. (I. S.) DECEMBER, 1903. Part 1. 



CONTENTS. 



PAGE 



I. — An Improved Polarizing Vertical Illuminator. By J. Joey, M.A., 

 D.Sc., F.E.S., Professor of Geology and Mineralogy, Trinity 

 College, Dublin ; Hon. Sec. Royal Dublin Society, ... 1 

 II. — How to introduce Order into tbe Relations between British Weights 

 and Measures. ByG. Johnstone Stonev, M.A., Sc.D.,F.R.S. 

 (Plate I.), .6 



III. — Photographs of Spark-Spectra from the Large Rowland Spectro- 

 meter in the Royal University of Ireland. Part II. : The 

 Ultra -Violet Spark-Spectrum of Ruthenium. By. W. E. 

 Adene?, D.Sc, A.R.C.Sc.L, Curator and Examiner in 

 Chemistry in the Royal University of Ireland, ... 24 



IV. — The Cohesion Theory of the Ascent of Sap : A Reply. By Henry 

 H. Dixon, Sc.D., Assistant to the Professor of Botany, Trinity 



College, Dublin, 48 



V. — The Penological Examination of Paving-Sets. Part I. By 

 J. Joey, B.A.I., Sc.D., F.R.S., F.G.S., Professor of Geology 

 and Mineralogy in the University of Dublin ; Hon. Sec. Royal 

 Dublin Society. (Plates II.-V.), 62 



VI. — On an Irish Specimen of Dopplerite. By Richard J. Moss, F.I.C., 



F.C.S., . . . . ... . . .93 



VII. — Tyloses in the Bracken Fern. (Pteris aquilina, Linn.). By 

 T. Johnson, D.Sc, F.L.S., Professor of Botany in the Royal 

 College of Science, and Keeper of the Botanical Collections, 

 National Museum, Dublin. (Plate VI.), . . . .101 



VIII. —A New Method of producing Tension in Liquids. By J. T. 



Jackson, M.A., 104 



IX. — A Transpiration Model. By Henry H. Dixon, Sc.D., Assistant 



to the Professor of Botany, University of Dublin, . . .114 

 X. — The Levinge Herbarium. By T. Johnson, D.Sc, F.L.S., Pro- 

 fessor of Botany in the Royal College of Science, and Keeper of 

 the Botanical Collections, National Museum, Dublin; and Miss 

 M. C. Knowles, . . .122 



The Authors alone are responsible for all opinions expressed in their Communications, 



■ 



DUBLIN: 

 PUBLISHED BY THE ROYAL DUBLIN SOCIETY. 



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1903. 



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