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Leader (1850-1860), 17th September 1853, Edition Town of 2, Page 904

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      Untitled Article

      The great topic of the week is * of course , the meeting of the British Association at Hull . ' Although we cannot by any means share the official enthusiasm and official hopes respecting the advancement of Science by such means—believing . Science takes quite other means- —although , moreover , we cannot , like Professor Phillips , regard the expenditure of forty thousand pounds in . the course of three and twenty years as a very magnificent indication of the activity and liberality of England ( we should like a comparison to be made with some other item of corporate

      expendituresay aldermanic feasts during three and twenty years !)—although we look upon these Meetings very much in the light of huge gatherings for gossip , laudation , and twaddle , relieved from contempt by some serious and useful WG rk—nevertheless , there is one aspect in which we regard them as potent influences : if they do not greatly advance Science , they do greatly advance the popularity of scientific pursuits , and so insensibly prepare the way for the final universal acceptance of Science as the basis of all education . How little do the worthy clergymen and worthy churchmen dream they are fostering their most formidable rival , in thus " patronizing" Science !

      The President ' s address was very able . He began by remarking how much more populous our solar system is than was suspected till quite recently . During the last twelve months , nine new planets have been discovered , four by our countryman , Mr . Hind . In fact , the search for them has assumed a systematic shape , and we may hope for a large accession to our astral maps . In noticing the two new theories of Heat , the President ' s Address is so worded as to give greater novelty to them than is actually the case ; but as they will probably be novel to the majority of our readers , we will quote the passage : —

      "A theory which proposes to explain the thermal agency by which , motive power is produced , and to determine the numerical relations between the quantity of heat and the quantity of mechanical effect produced by it , may be termed a dynamical theory ofTieat . Cai-not was the first to give to such a theory a mathematical form . His theory rested on two propositions which ¦ were regarded us axiomatic . The first embodied the abstract conception of a perfect thermo-dynamic engine , and has been equally adopted by the advocates of the new theory of heat . Again , suppose a given quantity of heat to enter a body l > y any process , and thereby to change its temperature and general physical state ; and then , by a second process , suppose the body to be restored exactly to its primitive temperature and condition , —Carnot ' s second fundamental proposition asserts that the quantity of heat

      which passes , out of the body into surrounding space , or into other bodies , in the form of heat , during the second operation , is precisely the same as that which passed into the body during the first operation . This view does not recognise the possibility of heat being lost by conversion into something else—and in this particular it is at variance with the new theory , which asserts that heat may be lost byconversion into mechanical effect . To elucidate this distinction , suppo . se a quantity of water to be poured into an empty vessel . It might then be asserted that , in emptying the vessel again , we must pour out just as much water as we had previously poured in . This would be equivalent to Carnot ' s proposition with respect to heat . But suppose a part of the water while in the vessel to be converted into vapour ; then it would not le true that in emptving the vessel the same quantity

      of water , in the form of water , must pass out of the vessel as had before pussed into it , since a portion would have passed out in the form of vapour . This is analogous to the assertion of the new theory with regard to heat , —which may be lost , according to that theory , by conversion into mechanical effect , in a manner analogous to that in which water may be said to be lost by conversion into vapour . Hut the new theory not only asserts generally the convertibility of heat into mechanical effect , and the converse , —but also more definitely , that , whatever be the mode of converting the one into the other—and whether heat bo employed to produce mechanical effect , or mechanical force be employed to produce hent , —the same quantity of the ono is always the equivalent of the same quantity of the other . This proposition can only bo established by experiment . Rumfonl , who was one of the firefc to adopt the fundamental notion of this theory as regards the nature of heat , made a rough attempt to determine the relation between the force producing

      friction and the . hoat generated by it ; but it was reserved for Mr . Jonle to lay the true foundation of this theory by a series of experiments which , in the philosophical discernment with which they were conceived and the ingenuity with which i , hey wero executed , have not often , perhaps , been surpassed . In whatever way he employed mechanical force to produce , heat , he found , approximately , the same quantity of heat produced by tho Biuue . amount of force ; the , force being estimated in foot-pounds according to the usual mode in practical mechanic .-- ' ,-- •/' .

      science : —¦ < N " Some of tho most interesting of recent discoveries in organic remains arc thoso which provo tho existence of reptilian life during tho deposition of houic of our oldest fosmliforous strata . An ulniont perfect skeleton of a reptile belonging to tho .. I IJatrnchiana or Lacortians was lately found in tho Old Rod Sandstone of Moray-. N shire . Tho remains of ii reptile wero also discovered last ; year by Sir Charles "* \ ¦ ^ iV \ J'Ve . M and Mr . Dawnon in the coal measures of Nova Ncoliii ; nnd a batraehoid [• > Vu \; V l ^ y ^ l fowil hns also been recognised in Hritish coal whale . But tho most ; curious evidence s ^ "" ^ 7 w £ il ° f th ° wrly existence of annuals above tho lower orders of organization on the fuce !„ . / v ^ : Sl- Mr **] of our globe , is that afforded by tho footprints discovered u eli . orfc time aim in m ^^ y ^ vS / Sf ^ St i

      Canada by Mr . Logan , on large slabs of the oldest fossiliferous rocks , — -those of the Silurian epoch . It was infen-ed from the more imperfect ; specimens first brought over , that these footmarks were the marks of some reptile ; but more perfect examples , afterwards supplied by Mr . Logan , satisfied Prof , Owen that they were the impressions of some animal belonging to the Articulata , probabl y a crustacean Thus tho existence of animals of the reptile type of organization during the carboniferous and Devonian periods is clearly established ; but no evidence has yet been obtained of the existence of those animals during the Silurian period . After the discoveries ' which 1 have mentioned , however , few geologists will perhaps be surprised should we hereafter find that higher forms of animal life were introduced upon the earth during- this early period than have yet been detected in its sedimentarv beds .

      " Many of you will be aware that there are two theories in geology , which may be styled * the theories of progression and . of non-progression respectively . The former asserts that the matter which constitutes the earth has passed through continuous and progressive changes from the earliest state in which it existed lo its actual condition at the present time . The earliest state here contemplated may have been , a fluid , or even a gaseous state , due to the enormous primitive heat of the mass , and it is to the gradual loss of that heat that the progressive change recognised by this theory is chiefly attributed . The theory of non-progression , on the contrary , recognises no primitive state of our planet differing essentially from its exist ing ' state . The only changes which it does recognise being those which are strictly periodical , and therefore produce no permanent alteration in the state of our globe . With reference to organic remains , the difference between these theories is exactly analogous to that now stated with reference to inorganic matter . Tho theory of progression asserts that there has been a . general advance in ' the forms of organic life from the earliest to the more recent geological periods . This

      advance must not be confounded , it should be observed , with that progressive development according to which animals of a higher organic structure are but the improved lineal descendants of those of the lowest grade , thus abolishing all distinction of species . It is merely meant to assert that the higher types of organic being are far more generally diffused at the present time , and far more numerous and varied than they were afc the earlier geological periods ; and that , moreover , at the earliest of those periods which the geologist has been able to recognise , some of these higher types had probablyno existence at all . " Each successive discovery , like those which I have mentioned , of the remains of animals of the higher types in the older rocks , is regarded by some geologists as an addition to the cumulative evidence by which they conceive that the theory of non-progression will be -ultimately established ; while others consider the deficiency

      in the evidence required to establish that theory as far too great to admit the probability of its being supplied by future discovery . Nor can tlie theory derive present support , it is contended , by an appeal to any properties of inorganic matter , or physical laws , with which we are acquainted . Prof . W . Thomson has recently entered into some very interesting speculations bearing on this subject , and suggested by the new theory of heat of which I have spoken . The heat of a heavenly body placed under the same conditions as the sun , must , it has been said , be ultimately exhausted by its rapid emission . This assertion assumes the matter composing the sun to have certain properties like those of terrestrial matter with respect to the generation and emission of heat ; but Prof . Thomson ' s argument places the subject on better grounds , admitting , always , the truth of the new

      theory of heat . That theory asserts , in the sense which I have already stated , the exact equivalence of heat and motive power ; and that a body , in sending forth heat , must lose a portion of that internal motion of its constituent particles on which its thermal state depends . Now , we know that no mutual action of these constituent particles can continue to generate motion which might compensate for the loss of motion thus sustained . This is a simple deduction from dy namical laws and principles , independent of any property of terrestrial matter which may possibly distinguish it from that of the sun . Hence , then , it is on these dynamical principles that we may rest the assertion that tho sun cannot continue for an indefinite time to emit the same quantity of heat as at present , unless Ins thermal be renovated from some extraneous sourceThe same conclusion may o

      energy , applied to all other bodies in tho universe which , like our sun , may bo centres <> t intense heat ; and , hence , recognising no adequate external supplies bent o renovate these existing centres of heat , Prof . Thomson concludes that the dispersion of heat , and consequently of physical energy , from the sun and stars into surrounding space without any recognisable means of re-concentration , is the existing ordeio Nature . In such case , the heat of the sun must ultimately bo diminished , and the physical condition of the earth therefore altered , in a degree altogether incorisistcn

      with the theory of non-progression . " If wo are to found our theories upon our knowledge , and not upon our ig " ^ ranco of physical causes and phenomena , I can only recognise in the existing » ' of things a passing phaso of the material universe . It muy be calculated i" « ^ ' and is demonstrnbly . so in some respects , to enduro under the action ol ^ u causes , for an inconceivable period of time ; but it has not , 1 think , receive * impress of eternal duration in characters which man is able to decipher . j ternal temperature any physical conditions of our own globe may not , nnu pro ^ cannot , have changed in any considerable degree since the first introMic . organic beings on its surface ; but I can ntill only recognise in its p hysio ^ » ^ during all geological periods , a ( Unto of actual though of exceedingly » l < nV V ^[ t c {{ sion , from an antecedent to some ultimate state , on the nature of which our ^ powers will not enable us to offer any conjecture founded on physical resenic i . ^^ theories , even , of which 1 have been speaking , may probably appear to some V ^ t dvoid of tionbut for will over bo friiug > mil in nut ior whjy w »»

      as no e presump ; many men they hh < u : vom imiMiuujiuon ; many men w » ' .- - - . .. j- deep speculative interest : and , lest mo add , no charge of presumption cani . ]»• ¦ . . ^ against them if entered ujkhi with . that caution and modesty which oug » our inquiries in these remote regions of physical science . ' * We notice with extreme regret that applications , made both > ¦ ' ^ Dir / HUY and Lord Aijkhdk . icn , for a grant to aid in the l" 1 ^ 1 " ' ' ^ ?! / ' ,,,,,, ^ , JIvxlky ' h Zoological and Physiological Researches in II . M . S . Hfl- l ( - . lmvc been ineffectual . What ' « votes" can Zoology and Vh ^ W ^ ol ,, r that they should have money spent on them ? VVlmt has liO "" Coalition to do with the advance , of Science ?

      ,.,. . i n , _ ..... ... .. i l 1 . 1 , i <) ul'f'tiOI'H The principle of " publishing societies , " which enables se < : »< ^ ^ public to secure works , Uy co-opemtion , wueh us no publisher w ° ^ ^ jl 0 take , has been found eminently successful iu the cases yet tric ( ,

      Untitled Article

      Critics are not the legislators , but the judges and police of literature . They do not makelaws—they interpret and try to enforce them . — EdtnburgMieneic .

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      904 THE LEADER . __ [ Saturday ,

  • Citation
    • Leader (1850-1860), Sept. 17, 1853, page 904, in the Nineteenth-Century Serials Edition (2008; 2018) ncse-os.kdl.kcl.ac.uk/periodicals/l/issues/vm2-ncseproduct2004/page/16/