A A TURE 



DR. H. STROUD'S 



Apparatus for 



DETERMINING THE 



VELOCITY OF 



SOUND IN AIR, BY 



THE METHOD 



OF RESONANCE. 



The Resonance Tube is 3 ft. 

 long, with a graduated scale 

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Price, in Polished Mahogany 

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SOIL.E: IVIJVKEESS 



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THE METALLURGY OF STEEL. 



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AN INTRODUCTION TO THE DESIGN OF BEAMS, GIRDERS, 

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CONSTRUCTIONAL STEELWORK: 



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OIL FUEL : Its Supply, Composition, and Application. 



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important Text B 'Ok "—Nature. 



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CALCAREOUS CEMENTS: 



Their Nature, Manufacture and Uses, with some Observations upon 



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THE INVESTIGATION OF MINE AIR: 



An Account by several Authors of the Nature, Significance, and Pra< tical 

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id Metalliferi 



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Edited by Sir C. LE NEVE FOSTER. D.Sc. F.R.S., and 

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[May 1 1, 1905 



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