36 



NATURE 



{Nov, 14, 1878 



governed by physical causes. But here we are embar- 

 rassed by the fact that no inquirer has been able to dis- 

 cover a clear periodic variation in the price of corn. This 

 is what Sir William Herschel attempted to do, at the 

 beginning of this century, in his truly prophetic inquiry 

 about the economic eflfects of the sun-spots ; but his facts 

 are evidently too few to justify any sure inference. Car- 

 rington also compared the sun-spot curve with that of 

 the price of com, without detecting any coincidence ; and 

 my own repeated inquiries have been equally without 

 result as to this point. The fact is, I believe, that 

 cereal crops, as grown and gathered in Europe, depend 

 for their success upon very complicated conditions, so 

 that the solar influence is disguised. But it does not 

 follow that other crops in other latitudes may not mani- 

 fest the decennial period. Dr. Schuster ' has pointed 

 out a coincidence between good vintages and minima of 

 sun-spots which can hardly be due to accident, and the 

 whole controversy about the connection of Indian famines 

 with the sun-spot period is of course familiar to all readers 

 of Nature. Now if we may assume Dr. Hunter's 

 famine theory to be true there is little difficulty in explain- 

 ing the remarkable series of periodic crises which I have 

 pointed out. 



The trade of Western Europe has'always been strongly 

 affected by communication with the Indies. Several of the 

 crises are distinctly traceable to this cause, especially those 

 at the beginning of the eighteenth century. That was a 

 time of wild enterprise in the tropical regions, as the 

 very names of the South Sea Company, the Mississippi 

 scheme, the Darien project, &c., show. The Dutch, 

 English, and French East India Companies were then 

 potent bodies, the constant subject of legislation and 

 controversy. Thus it is my present belief that to trade 

 with India, China, and probably other parts of the 

 tropical and semi-tropical regions, we must attribute the 

 principal fluctuations in European commerce. Surely 

 there is nothing absurd in such a theory when we remem- 

 ber that the present crisis is at least partly due to the 

 involvement of the City of Glasgow Bank in the India 

 trade, through the medium of some of their chief debtors. 

 Thus the crisis of 1878 is clearly connected with the 

 recent famines in India and China, and these famines 

 are confidently attributed to solar disturbance. 



To establish this view of the matter in a satisfactory 

 manner, it would be desirable to show that there has 

 been a decennial variation of trade with India during the 

 170 years under review. The complications and disturb- 

 ances produced in the statistics of such a trade by various 

 events are so considerable that I have not yet attempted 

 to disentangle them properly. Yet the accounts of the 

 merchandise (not including bullion) exported by the 

 English East India Company between the years 1708-9 

 and 1733-34 display such a wonderful tendency to decen- 

 nial variation, that I cannot refrain from quoting them. 

 As stated by Milbum in vol. i. p. xlviii. of his " Oriental 

 Commerce," they are as given in the following table, 

 except that I have struck off three places of figures useless 

 for our purposes : — 



Values of Merchandise Exported to India 



' Nature, vjI.xv'., p. 45. 



In the above table there are three well-marked maxima 

 in 1710-11, 1721-22, and 1731-32 at intervals closely 

 approximating to that of the sun-spot curve. I believe 

 that there are some traces of the same decennial variation, 

 in subsequent portions of the same tables. The fact that 

 this variation is difficult to trace may possibly explain the 

 absence of any serious crises in 1742 and 1752. 



Probably, however, we ought not to attribute the 

 decennial fluctuation wholly to Indian trade. It is quite 

 possible that tropical Africa, America, the West Indies,, 

 and even the Levant are affected by the same meteoro- 

 logical influences which occasion the famines in India. 

 Thus it is the nations which trade most largely to those 

 parts of the world, ajid which give long credits to their 

 customers, which suffer most from these crises. Holland 

 was most easily affected a century ago ; England is most 

 deeply affected now ; France usually participates, together 

 with some of the German trading towns. But I am not 

 aware that these decennial crises extend in equal severity 

 to such countries as Austria, Hungary, Switzerland, Italy, 

 and Russia, which have comparatively little foreign trade. 

 Even when they are affected, it may be indirectly through 

 sympathy with the great commercial nations. 



There is nothing in this theory inconsistent with the 

 fact that crises and panics arise from other than meteoro- 

 logical cau:es. There was a great political crisis in 1798, 

 a great commercial collapse in 1810-11 (which will not 

 fall into the decennial series) ; there was a Stock Ex- 

 change panic in 1859; and the great American collapse 

 of 1873-75. There have also been several minor dis- 

 turbances in the money market, such as those of February,. 

 1861, May and September, 1864, August, 1870, November, 

 1873 ; but they are probably due to exceptional and dis- 

 connected reasons. Moreover, they have seldom, if ever, 

 the intensity, profundity, and wide extension of the true 

 decennial crises. 



If it were permitted to di-aw any immediate conclusion 

 from these speculations, I should point to the necessity of 

 at once undertaking direct observations upon the varying 

 power and character of the sun's rays. There are hundreds 

 of meteorological observatories registering, at every hour 

 of the day and night, the most minute facts about the 

 atmosphere ; but that very influence, upon which all 

 atmospheric changes ultimately depend, the solar radia- 

 tion^ is not, I believe, measured in any one of them, at least 

 in the proper manner.^ Pouillet showed long ago (1838) 

 how the absolute heating power of the sun's rays might 

 be accurately determined by his Pyrheliometer. This 

 instrument, and the results^ which he drew from its use, 

 are fully described in his "Elements de Physique Expdri- 

 mentale et de Metdorologie " (livre 8™% chap, i., section 

 285). But I have never heard that his experiments have 

 been repeated, except so far as this may have been done 

 by Sir John Herschel, with his so-called Actinometer, as 

 described by him in the Admiralty Manual of Scientific 

 Inquiry. I fancy that physicists still depend upon 

 Pouillet' s observations in 1837 and 1838 for one of the 

 most important constants of the solar system, if constant 

 it can be called. While astronomers agitate themselves 

 and spend infinite labour about the two-hundredth 

 planetoid, or some imperceptible satellite, the very foun- 

 tain of heat and light and life is left unmeasured. Pouillet 

 indeed assumed that the heating power of the sun's rays 

 is a constant quantity, which accounts for his not con- 

 tinuing the solar observations. But, if there is ahy truth 

 in all these sun-spot speculations, there must be a periodic 

 variation in the sun's rays, of which the sun-spots are 

 a mere sign, and perhaps an unsatisfactory one. It is 

 possible that the real variations are more regular than the 

 sun-spot indications, and thus perhaps may be explained 

 the curious fact that the decennial crises recur more regu- 



' Of course there have been .ibundance of black-bulb thermcmeter obser- 

 vations made in various parts of the world, but I doubt whether they are ot 

 much value. 



