226 Britain's Heritage of Science 



on the subject of the culture of trees. It is held to be 

 responsible for a great outbreak of tree-planting. The 

 introduction to Nisbet's edition gives figures which demon- 

 strate the shortage in the available supply of oak timber 

 during the seventeenth century. The charm of Evelyn's 

 style and the practical nature of his book, which ran into 

 four editions before the author's death, arrested this decline 

 ("be aye sticking in a tree ; it will be growing, Jock, when 

 y're sleeping " as the laird of Dumbiedykes counselled his 

 son), and to the " Sylva " of John Evelyn is largely due the 

 fact that the oak timber used for the British ships which 

 fought the French in the eighteenth century sufficed, but 

 barely sufficed, for the national needs. 



Pepys, whose naive and frank self -revelations have made 

 him the most popular and the most frequently read of diar- 

 ists, was not quite of the same class of student to which 

 Lord Herbert of Cherbury or John Evelyn belonged. But, 

 gifted as he was with an undying and insatiable curiosity, 

 nothing was too trivial or too odd for his notice and his 

 record; and, being an exceptionally able and hard-working 

 Government servant, he took great interest in anything 

 which was likely to affect the Navy. He discoursed with the 

 ingenious Dr. Kuffler " about his design to blow up ships," 

 noticed " the strange nature of the sea-water in a dark night, 

 that it seemed like fire upon every stroke of the oar " 

 an effect due, of course, to phosphorescent organisms float- 

 ing near the surface and interested himself incessantly in 

 marine matters. 



Physiology and mortuary objects had, for him, an interest 

 which was almost morbid. He is told that " negroes drounded 

 look white, and lose their blackness, which I never heard 

 before," describes how " one of a great family was . . . 

 hanged with a silken halter ... of his own preparing, 

 not for the honour only " but because it strangles more 

 quickly. He attended regularly the early meetings of the 

 Royal Society at Gresham College, and showed the liveliest 

 interest in various investigations on the transfusion of 

 blood, respiration under reduced air pressure and many 

 other ingenious experiments and observations by Sir George 

 Ent and others. On January 20th, 1665, he took home 



