ASTRONOMICAL PHENOMENA AND PROGRESS. 



pas. The- light of three nebulro was corfipared 



with that of a sperm candle burning 158 grs. an 



with tin- following result : the estimation 



:ii:i.l.- in tho brightest part of tho nebula): 



; f,-29, IIIIV 

 .iiniilur neb'ila In Lyra 



!n in li IJI-H nebula 



ih which have thus far been ex- 

 -1 may hi- divided into t\v<> great groups; 

 -iving hright lines with :i taint spectrum 

 1, the other giving apparently a con- 

 ct nun. The nebula in tho sword- 

 handle of Orion exhibits three bright lines; and 

 telescope reveals a largo num- 

 \ery minute red stars, which do not fur- 

 nish u vi<ihle spectrum. The bluish-green raat- 

 thH nebuloj has not yet been resolved. 

 Tho question arises: Are all the unresolved 

 M.-OUS, and those which give a con- 

 tinuous spectrum clusters of stars ? Half of tho 

 nehuUe which give a continuous spectrum have 

 resolved, while of the gaseous nebulre 

 have certainly been resolved. 

 The Force which prolongs the Heat and Light 

 Sun and other Fixed Stars. Prof. Ennis, 

 in his interesting treatise on tho " Origin of tho 

 ," propounds the following theory of tho 

 force winch has given so prolonged a duration 

 to the light and heat of the sun : That the 

 chemical force now active in tho sun is the 

 conversion or conservation of the atomic force 

 of repulsion which once held the solar system 

 in a nebulous condition that condition being 

 i' inconceivable rarity. This atomic force 

 have been inconceivably great, and, be- 

 ing indestructible, must still exist. In fact, 

 it is now, and has long been, passing off as light 

 and heat through conversion into chemical 

 forces. But why suppose that the original re- 

 pulsive force is converted into light and heat 

 through chemical agencies, rather than through 

 electricity or some other means ? The answer 

 is because the present action in the sun, and 

 in the fixed stars, and the former action in our 

 earth, all strongly indicate chemical action. 

 'Hiis force now operates in tho sun and other 

 iixed stars by three methods. 



First. There are reasons to believe, from tho 

 nature of matter, that the materials in the sun 

 may possibly give out more heat than those in 

 our earth. On this planet -one substance gives 

 out more heat than another of equal weight ; 

 as, for instance, a pound of hydrogen produces 

 more than four times the heat of a pound of 

 carl urn. Between other elements there are 

 similar differences. Chemical diversities seem 

 endless in number, and immeasurable in ex- 

 tent. Every star, so far as yet known, has a 

 ditl'erent set of fixed lines in the spectrum, al- 

 though there are certain resemblances between 

 tlu in. It may, therefore, be concluded that 

 each star lias, in part at least, its peculiar 

 modifications of matter called simple ele- 

 ments. The peculiar elements of tho sun may 

 ditl'er from ours in heat- producing power as 

 much as ours differ from one another in den- 



sity, and this is as 250,700 (hydrogen) to 1 (pla- 

 tinum). The assumption that the material^ of 

 the sun can give out no more heat, pound per 

 pound, than the materials of tho earth, ia there- 

 fore unfounded. 



Second. Tho conditions for producing heat 

 in the vast laboratory of tho sun, are different 

 from those with which wo are familiar on this 

 earth. Combustion, with us, is always between 

 a gaseous body and another which may be 

 either gaseous, liquid, or solid; while in the sun 

 the chief combustion takes place between liquid 

 materials, for the liquid body of the sun is the 

 hottest. Pressure exercises an important in- 

 fluence on combustion ; and the pressure of 

 the atmcsphere of the sun must be inconceiv- 

 ably great considering the height of the atmos- 

 phere and the powerful attraction of the sun ; 

 but even that is as nothing compared with the 

 pressure in the liquid body of the sun, many 

 thousand miles down. The force of chemical 

 attraction which impels atoms to unite in col- 

 lision, thereby causing heat, may bo in some 

 way more powerful in the sun than on the 

 earth. The ether or ethers around the sun 

 may contribute to the production of heat. 



Third. New combustibles may now be pre- 

 paring in the sun from materials which have 

 already been burned. According to the neb- 

 ular theory, what we call tho simple elements 

 are mere modifications of one, general fundamen- 

 tal matter. These modifications have arisen 

 during the process of condensation, and must 

 still be forming in the sun, because the sun is 

 eight times less dense than is required by the 

 law of density in the solar system, and will con- 

 tinue to form until its fires are burned out, 

 and its due density is reached. Our " simple 

 elements " may be not only compounds but 

 double compounds, or compounds that are the 

 result of hundreds or thousands of compound- 

 ings. In this way there must have been, at 

 different periods, entirely different sets of ele- 

 ments in the sun. After one set had combined, 

 producing light and heat by the combination, 

 the resulting compound products may have 

 again combined, with the samp effect of light 

 and heat, and so on in a continuous line of 

 changes until the sun has attained its proper 

 density, its fires are extinguished, and it be- 

 comes a " lost star," like the earth and the 

 other members of the solar system. 



With regard to the ultimate identity of suns, 

 planets, and moons, Prof. Ennis says : " Wo arc 

 really treading on a fixed star. Here we have 

 an opportunity of leisurely observing how a 

 fixed star appears after its light has gone out. 

 As in a forest we note tho progress of the oak, 

 from the acorn to tho tall tree, some just rising 

 from the ground, others vigorous in the sapling 

 growth, and others whose trunks are populated 

 with mosses and lichens, and whose branches 

 are alive with birds, so we can se* like stages 

 of progress among tho heavenly bodies, our 

 earth included. Some arc glowing with tho 

 fervor of most intense heat; others, like ou 



