Sir "Joseph Petavel 187 



the reasons why vessels roll and pitch, and the effects of 

 this buffeting by the waves. This man, whom many 

 of our readers will regard as a true martyr in the cause of 

 Science, goes for sea voyages with an ingenious recording 

 instrument as his companion. But his vogages differ 

 from other people's. He deliberately sets out in search of 

 rough weather. He is so keen to endure the worst the sea 

 can do that passages are booked for him in the winter on 

 cargo boats, when the Atlantic can be relied on to satisfy 

 his appetite for storms. 



Among his trophies is a graph of pitching in a 10,000- 

 ton cargo-boat during a big storm which makes the land- 

 lubber sick to look at. And he will tell you exultantly of 

 a roll of thirty degrees he once experienced ; this he has 

 carefully stored among the data he is collecting for an 

 effort to make vessels steadier in bad weather — surely 

 an effort for which humanity will thank him. 



Important as are these researches, on the sea and in 

 the famous Froude Tank, they are only one part of the 

 work of this wonderful laboratory, which does many 

 other things just as remarkable and valuable — indeed, the 

 activities of the National Physical Laboratory are so 

 varied and extensive that it would need a book much 

 larger than this to give an adequate picture of the real 

 wonders of its work. 



There are six other main sections : Physics, Electricity, 

 Engineering, Metallurgy, Aerodynamics, and Metrology. 



Not long ago the Engineering Department had a very 

 interesting problem to tackle. The House of Commons 

 had complained of bad ventilation, so the problem was 

 turned over to the National Physical Laboratory. There 

 the scientists built a scale model of the House, and from 

 their observations were able to make valuable suggestions 

 for improving the air breathed by Members. 



Next door to that model in the Engineering Depart- 

 ment is a fearsome-looking steel structure whose function 



