Ogilvie 



INTRODUCTION 



Background 



The hydrodynamic theory of ships was born in the last half-decade of the 

 nineteenth century, and it was a spectacular beginning, for within three years 

 there appeared three papers by Krylov and the famous paper by Michell. Unfor- 

 tunately, the response to these papers was not what they deserved, and many 

 years passed before naval architects again considered their problems as sci- 

 entific problems. We look back and see a few hardy souls struggling to progress 

 against the apathy of their own profession. Not until almost 1950 was there a 

 general renaissance of interest in the possibility of finding scientific solutions 

 to the naval architect's hydrodynamics problems. 



Then, in 1953-4, there was another spectacle comparable to the one over 

 fifty years earlier. In these two years there appeared the papers by St. Denis 

 and Pierson (1953) and Peters and Stoker (1954). The former suggested the 

 procedure for relating to reality the highly idealized hydrodynamic theory of 

 ship motions (as it then existed). The latter provided a logical foundation for 

 this idealized theory and, in particular, it set forth clearly the hypotheses 

 involved. 



Neither of these two papers presented the final words on the subject; on the 

 contrary, each raised more questions than it answered. But these authors were 

 more fortunate than Krylov and Michell, for their papers were followed by an 

 explosion of activity. By 1957, it was possible for the Netherlands Ship Model 

 Basin to sponsor a symposium on seakeeping at which there were presented 

 nearly fifty papers, some on the most basic scientific aspects of seakeeping 

 problems. 



Now, seven years later, we have again come together to (1) assess our 

 progress, (2) discuss our latest findings, and (3) orient ourselves toward further 

 discoveries on "the way of a ship in the midst of the sea." My own purpose is 

 concerned primarily with the first of these three, viz., to look back over the 

 last few years and attempt to evaluate our progress. I shall be discussing al- 

 ready published work almost exclusively. Of course, I cannot ignore work that 

 is in progress, but a few words on such will suffice, for other speakers here 

 are ready and willing to present their latest findings. Neither can I ignore the 

 future, and in fact my whole presentation will be somewhat biased towards what 

 I consider the most auspicious recent trends in research in our field. 



Scope 



In naval architecture, as in all branches of engineering, the designer is 

 faced with immediate demands. During the past decade it has become evident 

 that it would be not only desirable but perhaps even feasible to calculate the 

 motions of a ship, given only a geometrical description of the ship and adequate 

 information about its sea environment. Of course, shipbuilders and shipowners 

 want this information now , and so it has been incumbent on the naval architec- 

 ture profession to produce techniques as good as the state of the art allows. 



