May 27, 1920] 



NATURE 



393 



diseases, compiled by the Chief Veterinary Officer 

 of the Protectorate, should be read in conjunction 

 with the author's chapter on cattle. With refer- 

 ence to measures adopted to combat the spread of 

 rinderpest, there is an interesting illustration 

 showing the method of hyperimmunising cattle. 



The book concludes with a chapter detailing 

 the assistance furnished by British East Africa 

 and the sacrifices made by both Europeans and 

 natives in furtherance of the military operations 



which resulted ultimately in the conquest of what 

 is now known as Tanganyika Territory. 



Those who, like Lord Cranworth, have the 

 interests of British East Africa at heart will 

 welcome this volume, with its purpose of bringing 

 to the Protectorate an influx of recruits of the 

 right standard requisite to further the develop- 

 ment of its resources, particularly in view of the 

 existing demand for the raw materials required 

 in the reconstruction of the Empire's industries. 



Weather Notes of Evelyn, Pepys, and Swift in Relation to British Climate. 



By Capt. C. J. P. Cave. 



THE interest in weather notes from old diaries 

 lies in the fact that they may throw some 

 light on the vexed question whether meteorological 

 conditions in Western Europe are changing. The 

 diaries of Evelyn and Pepys have been quoted 

 by both believers and unbelievers in changing 

 conditions, and it must regretfully be admitted 

 that the question is, as yet, by no means easy 

 to answer. Evelyn's diary extends from 1620 

 to 1706, but during this long period there 

 are, on the average, only about eight weather 

 notes to every three years. As a rule, we find only 

 very outstanding phenomena recorded, such as 

 serious droughts, great storms, or hard frosts. 

 Evelyn's diary has, however, never been published 

 in full, and it is quite possible that the complete 

 diary may contain a great deal more information 

 on the subject. Pepys 's diary extends only from 

 1660 to 1669, and is, therefore, too short to 

 enable us to draw any safe conclusions. His 

 weather notes are, however, far more numerous 

 than Evelyn's, there being remarks bearing on 

 the weather on an average of sixty-two days a 

 year. Like Evelyn, he mentions outstanding 

 features, but he also frequently mentions the 

 weather as it affected his movements or his health, 

 so that we get a much better record for the few 

 years during which Pepys kept a diary than we 

 do for the longer period from Evelyn. Neither 

 writer is by any means infallible in his recollection 

 of past weather, and both can be confuted 

 from their own writings regarding events that 

 they describe as unprecedented in their memories. 

 The most significant facts from which to gauge 

 weather conditions, in times before instrumental 

 readings, are hot summers, droughts, wet spells, 

 and cold winters. So far as hot summers are 

 concerned, we have little to go on. Both writers 

 complain of the heat at times, but the only really 

 exceptionally hot summer seems to have been that 

 of 1698, mentioned by Evelyn. Nor do we get 

 very much ground to go on in droughts and wet 

 spells. We are, therefore, restricted to cold 

 winters, and especially to the freezing of the 

 Thames, for evidence of any change in climate 

 between the seventeenth century and the present 

 time. The evidence was discussed by several 

 writers in Symons's Meteorological Magazine in 

 191 1 and 1912, and different writers came to 

 NO. 2639, VOL. 105] 



diametrically opposite conclusions. Mr. Walter 

 Sedgwick mamtained that the intensity of falls of 

 snow was likely to be exaggerated by the seven- 

 teenth-century diarists, for when roads were 

 normally bad, traffic would have been far more 

 seriously affected by snow than it is to-day. Mr. 

 W. H. Dines, on the other hand, contended that 

 when roads were always bad during the winter, 

 ** it was a matter of indifference whether roads 

 were blocked by snowdrifts." It is also said that 

 the number of references to snow in Evelyn's 

 diary are very few, but it is quite certain that we 

 do not find ieferences to snow on nearly all the 

 occasions when it occurred. In December, 1648, 

 Evelyn says : " This was a most exceeding wet 

 year — neither frost nor snow all the winter for 

 more than six days in all " ; but none of these six 

 days are otherwise mentioned in the published 

 diary. The winter of 1657-58 was extremely cold, 

 and it is almost certain that there must have been 

 snow ; but none is specifically mentioned. 



It is certain that the Thames in London froze 

 more often in the seventeenth than in the nine- 

 teenth centuiy, but some hold that this was due 

 to the fact that the river was not embanked, and 

 that Old London Bridge offered such an obstruc- 

 tion that the water above the bridge froze more 

 easily than it does to-day. The Thames in London 

 is recorded to have been frozen, or nearly frozen, 

 on seven occasions during the period over which 

 Evelyn kept his diary, and it is almost certain 

 that it must have been frozen also in 1658. It is 

 noticeable that the freezing in November, 1662, 

 is mentioned by Evelyn, but not by Pepys, while 

 the freezings of December, 1665, and January, 

 1667, are mentioned by Pepys, but not in the pub- 

 lished diary of Evelyn. It seems as though the 

 freezing of the Thames was not looked on as such 

 a very out-ot the-way event, while slight frosts or 

 small falls of snow might pass unnoticed. There 

 were, of course, winters when there was little or 

 no frost or snow, but they were looked on as 

 very exceptional, and caused much apprehension 

 as likely to "threaten a plague," and fasts were 

 ordered by Parliament to pray for "more season- 

 able weather." 



From the evidence in Pepys 's diary the present 

 writer thought at first that " there seems no reason 

 to suppose that the weather " in the seventeenth 



