Nov. 14, 1878] 



NA TURE 



Agenia, Aporus, Miscophus, Ammophila, Crabro, Cerceris, 

 Philanlh«s, and some others, all of which stupefy the caterpil- 

 lars, spider?, or bees, which they store up for the nourishment 

 of their brood, and it would be desirable to have it pointed out 

 to what genera the insects really belong. The species seen by 

 Mr. Cecil, in a collection at Athens, which is described as "a 

 jin-bodicd variety," is, I think, a species of the genus Ammo- 

 hila, or of Pompilus ; that obser\'ed by Mr. Armit, of Queens- 

 nd, is probably a species of Pclopaeus. Some further defini- 

 ijn of the insects I consider highly desirable, as the general 

 term wasp must, I beKeve, lead to a veryfalse conclusion. 

 British Museum, November 2 " Fredk. Smith 



The Expected Meteor. Shower 



The meteor shower of Biela's comet, referred to in your 



■" Astronomical Notes " as likely to occur on the 27th inst., should 



also be looked for on several evenings preceding that date. 



Last year there were more of these slow-moving Andromedes on 



'la 25th than on the 27th of November. On the former night, 



om 5h. 30m. to 7h., I saw sLxteen shooting stars, seven of 



liich belonged to this stream, for they showed a good radiant 



: R.A. 24° Dec. 45° N. Yet on the 27th only two others were 



ted out of a total of 10 recorded during a watch from gh. 



loh. 30m. An occasional look out is therefore advisable on 



r.eral nights about the 27th, when, if meteors are seen in more 



-va. ordinary profusion, it will be important to recorxi their 



.mbers and paths. W. F. Denning 



Ashleydown, Bristol, November 7 



Geological Climate and Geologfical Time 



In considering the climatic changes which have evidently 



ken place on various parts of the earth's surface, it seems to 



e that what may have been a very important factor has been 



ther strangely left out of calculation by physicists, never 



ving been noticed hitherto, as far as I am aware. It is that 



: the heat which must at one period or other have been trans- 



itted from the moon. There can be scarcely a doubt that this 



ist at one time have influenced the earth's climate to a very 



werful degree, producing the effects of a second or ad- 



.ional sun. In the absence of any perceptible marks of 



Jiospheric or aqueous erosive actbn on the moon it is at pre- 



:it impossible to arrive at any idea of its relative age or at 



.hat period its heat may have been most abundantly radiated ; 



but if the much hotter climate which once prevailed in northern 



latitudes could be referred to this cause it might give us some 



vie to the difficulty. Something also might be done in com- 



ring the various changes of climate which have taken place in 



-itain parts of the earth's surface, as indicated by geological 



idence, with the actual course of the moon. The subject is at 



st worth entertaining, and may be recommended to the con- 



leration of physicists. William Davies 



10, Guildford Street, Russell Square, November 4 



A "New Galvanometer" 



The galvanometer (with its coil moving about a horizontal 

 : is) described by iDr. Obach in Nature, vol xviii. p. 707, is 

 t new. Prof. Pickering has fnUy described it, under the name 

 : Cosim galvanometer, in his " Elements of Physical Manipula- 

 tion," Part 2 (1876), p. 260. ^Vhen this instrument was first 

 u;ed I do not know. R. E. B.VYNES 



Christchurch, Oxford, November 9 



I 



COMMERCIAL CRISES AXD SUN-SPOTS^ 



" Thou Sua, of this great world both eye and scul." 



T is curious to notice the variety of the explanations 

 offered by commercial writers concerning the cause 

 •of the present state of trade. Foreign competition, beer- 

 drinking, over-production, trades-unionism, war, peace, 

 ^vant of gold, superabundance of silver, Lord Beacons- 

 field, Sir Stafford Northcote, their extravagant expendi- 

 tiu-e, the Government policy, the wretched Glasgow Bank 



This article, although treating the same subject, and partially containing 

 '^^. ^^"^^ ^ ? paper by the same writer, read at the recent meeting of 

 - cntish Association, is a distinct composition. The paper in question 

 ' probably be published elsewhere. 



directors, Mr. Edison and the electric light, are a few of 

 the happy and consistent suggestions continually made to 

 explain the present disastrous collapse of industry and 

 credit 



It occurs to but few people to remember that 'what is 

 happening now is but a mild repetition of what has 

 previously happened time after time. October, 1878,15 

 comparable with May, 1866, with November, 1857, with 

 October, 1847, and, going yet further back, with a some- 

 what similar condition of things, in 1837, in 1825-26, and 

 even in 1815-16. The incidental circumstances of these 

 commercial collapses have indeed been infinitely diversi- 

 fied. At one time the cause seemed to be the misconduct 

 of the great firm of Overends ; in 1857 there was the 

 mutiny in India, the peace with Russia, and a commercial 

 collapse in the United States ; in 1847 occurred the Irish 

 famine and a failure of European harvests generally, 

 following upon the great railway mania; the crisis of 

 1837 succeeded an immense expansion of home trade, the 

 establishment of joint stock banks, and the building of 

 multitudes of^factories and other permanent works ; 1825 

 was preceded by extravagant foreign speculations and 

 foreign loans ; 1815 was the year of the general peace. 

 All kinds of distinct reasons can thus be given why trade 

 should be now inflated and again depressed and collapsed. 

 But, so long as these causes are various and disconnected, 

 nothing emerges to explain the remarkable appearance 

 of regularity and periodicity which characterises these 

 events. 



The periodicity of the earlier portion of the series is so 

 remarkable that, even without the corroboration since 

 received, it convinced scientific inquirers that there 

 was some deep cause in action. Dr. Hyde Clarke, for 

 instance, wrote, more than thirty years ago, a paper 

 entitled " Physical Economy — a preliminary inquiry into 

 the physical laws governing the periods of famines and 

 panics." This paper was published in the Railway 

 Register for 1847, and is well worth reading. In the 

 commencement he remarks : "We have just gone through 

 a time of busy industry, and are come upon sorrow and 

 ill-fortune ; but the same things have befallen us often 

 within the knowledge of those now living. Of 1837, of 

 1827, of 1 8 17, of 1806, of 1796, there are men among 

 us who can remember the same things as we now see ia 

 1847. A period of bustle, or of gambling, cut short in 

 a trice and turned into a period of suffering and loss, is 

 a phenomenon so often recorded, that what is most to 

 be noticed is that it should excite any wonder." Dr. 

 Hyde Clarke then proceeds to argue in a highly scientific 

 spirit that events so regularly recurring cannot be attri- 

 buted to accidental causes ; there must, he thinks, be 

 some physical groundwork, and he proposed to search this 

 out by means of a science to^be called Physical Economy. 

 In the third page of his paper he tells us that he had 

 previously written a paper on the laws of periodical or 

 cyclical action, printed in Herapath's Railway Magazine 

 for 1838. "At this time," he says, "it was my impres- 

 sion that the period of speculation was a period of ten 

 years, but I was led also to look for a period of thirteen 

 or fourteen years. ... In the course of these inquiries I 

 looked at the astronomical periods and the meteorological 

 theories without finding anything at all available for my 

 purposes." A httle below Dr. Hyde Clarke continues : — 

 "Still thinking that the interval was an interval of about 

 ten years, I was, during the present famine, led to look 

 for a larger period, which would contain the smaller 

 periods, and as the present famine and distress seemed 

 particularly severe, my attention was directed to the 

 famine so strongly felt during the French Revolution. 

 This gave a period of about fifty-four years, with five 

 inter-vals of about ten or eleven years each, which I took 

 thus : — 



"1793 1804 181S 1826 1837 1S47." 



Dr. Hyde Clarke was by no means the only statist who 



