424 



SCIENCE. 



[N. S. Vol. ir. Xo. 40. 



had onlj^ recentlj' been commenced at the 

 dockj'ards of "Woolwich, Sheerness, Ports- 

 mouth and Plj^mouth, on the request of the 

 Royal Society, and no information had been 

 collected upon the tides on the coasts of 

 Scotland and Ireland. The British Asso- 

 ciation may feel pride in the fact that 

 within three years of its inception, viz. by 

 1834, it had induced the Corporation of 

 Liverpool to establish two tide gauges, and 

 the Government to undertake tidal obser- 

 vations at 500 stations on the coasts of 

 Britain. 



Another cognate instance is exemplified 

 by a paper read at the second meeting, in 

 1832, upon the State of ISTaval Architecture 

 in Great Britain. The author contrasts the 

 extreme perfection of the carpentry of the 

 internal fittings of the vessels with the re- 

 markable deficiency of mathematical the- 

 ory in the adjustment of the external form 

 of vessels, and suggests the benefit of the 

 application of refined analysis to the vari- 

 ous practical problems which ought to in- 

 terest shipbuilders — problems of capacitj^, 

 of displacement, of stowage, of velocitj^, of 

 pitching and rolling, of masting, of the ef- 

 fects of sails and of the resistance of fluids; 

 and, moreover, suggests that large-scale ex- 

 periments should be made by Government, 

 to afford the necessarj' data for calculation. 



Indeed, when we consider how completely 

 the whole habit of mind of the populations 

 of the western world has been changed, 

 since the beginning of the century, from 

 willing acceptance of authority as a rule of 

 life to a universal spirit of inquiry and ex- 

 perimental investigation, is it not probable 

 that this rapid change has arisen from so- 

 ciety having been stirred to its foundations 

 by the causes and consequences of the 

 French Revolution ? 



One of the earliest practical results of 

 this awakening in France was tiie convic- 

 tion that the basis of scientific research lay 

 in the accuracj' of the standards by which 



observations could be compared; and the 

 following principles were laid down as a ba- 

 sis for their measurements of length, weight 

 and capacity, viz.: (1) That the unit of lin- 

 ear measure applied to matter in its three 

 forms of extension, viz.: length, breadth 

 and thickness, should be the standard of 

 measures of length, surface and soliditj' ; 

 (2) that the cubic contents of the linear 

 measure in decimeters of pure water at the 

 temperature of its greatest density should 

 furnish at once the standard weight and the 

 measure of capacitj'.^'^ The metric system 

 did not come into full operation in France 

 till 1840; and it is now adopted by all 

 countries on the continent of Europe except 

 Russia. 



The standards of length which were ac- 

 cessible in Great Britain at the formation 

 of the Association were the Parliamentary 

 standard yard lodged in the Houses of Par- 

 liament (which was destroyed in 1834 in 

 the fire which burned the Houses of Parlia- 

 ment), the Royal Astronomical Society's 

 standard and the 10-foot bar of the Ord- 

 nance Survey. The first two were as- 

 sumed to aflbrd exact measurements at a 

 given temperature. The Ordnance bar was 

 formed of two bars on the principle of 

 a compensating pendulum, and afforded 

 measurements independent of temperature. 

 Standard bars were also disseminated 

 throughout the country, in possession of 

 the corporations of various towns. 



The British Association early recognized 

 the importance of uniformitj^ in the record 

 of scientific facts, as well as the necessitj"^ 

 for an easj' method of comparing standards 

 and for verifying differences between instru- 

 ments and apparatus required bj^ various 

 observers pursuing similar lines of iuvesti- 



*The liter is tlie volume of a kilogramme of pure 

 water at its maximum ilensitj', and is slightly less 

 than the liter was intended to Ije, \iz., one cubic 

 decimeter. The weight of a cubic decimeter of pure 

 water is 1.000013 kilonrammes. 



