120 Transactions of the Royal Canadian Institute 



during the last quarter of a century advances which would have been 

 bold to rashness at an earlier time, have become almost routine. This 

 rule of step-by-step progress referred tt> above, has at least one aston- 

 ishing exception: Nearly seventy years ago a famous English civil 

 engineer and bridge builder, Brunei, turned to shipbuilding, maintaining 

 that the larger the ship the more economical and efficient her operation, — 

 a perfectly sound scientific principle. Brunei attracted large capital, 

 and in association with Scott Russell, a shipbuilder and naval architect 

 finally produced the Great Eastern which was indeed a giant to a pigmy 

 when compared with the other iron steamships of her day, — (we must 

 not forget that iron shipbuilding was a very recent art in those days). 

 The Great Eastern had her keel laid in 1854, was launched in 1858 after 

 many difficulties, and pu^t in service in 1859. She fell short of the 

 expectations of her designers in some respects, and was not a commercial 

 success mainly because she was too big a step forward, but that she 

 was built at all was truly a remarkable accomplishment and due largely 

 to the fact that Brunei utilized to tlhe utmost the engineering sciences of 

 the day. Not until 1899 was a vessel the size of the Great Eastern 

 again built. 



Let us consider now a little more in detail a few applications of 

 science to essential features of the ship. Three primary problems with 

 which the naval architect has to deal are the stability, the strength and 

 the propulsion of the ship. One thing that is obviously necessary for 

 a successful ship is that it should not capsize. The science of mathe- 

 matics has been applied to investigating the question of stability of 

 vessels, — stability being the measure of the ability of a ship to remain 

 upright or return to the upright when inclined by wind or waves. In 

 the ships of ancient days, stability was largely gained by carrying ballast 

 or heavy weights low down, the amount and location of such ballast 

 being frequently determined by trial after the ship was completed. 

 This meant that, except when copying a preceding vessel, it was not 

 known in advance whether a proposed design would be satisfactory as 

 regards stability. I believe about the first person to apply scientific 

 methods to this problem (at least the first of record) was a French 

 mathematician named Bouger, who developed the idea of the meta- 

 center. In mathematical language, the metacenter is the center of 

 curvature of the locus of the center of buoyancy of the vessel as it is 

 inclined. As a practical proposition the metacenter is the limit above 

 which we cannot locate the center of gravity of the ship without having 

 her initially unstable and unable to float upright. The greater the dis- 

 tance of the center of gravity below the metacenter, the stift'er the ship 

 is initially, or the harder to heel from the upright position. It is supposed 



