February, igo6.] 



KNOWLEDGE & SCIENTIFIC NEWS. 



347 



take the process of fertilisation. Flowers with petals, 

 but lacking the organs of reproduction, are, of course, 

 unknown in Nature, whilst there are many instances 

 where the stamens and pistil are in evidence, but in 

 which the corolla is quite absent. So that the well-nigh 

 inevitable conclusion is that the stamens and the pistil 

 were developed from the leaf first of all, the corolla and 

 its envelope, the calyx, later on. Thus we must regard 

 the strange midway organs which have been noticed in 

 the case of the flower of the Water Lily rather as 

 degenerate stamens than as advancing petals. 



The subject is such a profound one that it is not 

 possible to do more than to hint at the wonderful 

 process whereby the different parts of the flower as we 

 see it to-dav have been developed. One cannot help 



monstrosity of the Common Pea, where the lobes of the 

 pod have [failed to close together. 



being impressed with the manner in which at every 

 point one is brought face to face with the immense im- 

 portance of the leaf in the economy of the plant. In 

 the leaf is situated that basis of the plant life — proto- 

 plasm, present in the specialised form of chlorophyll. 

 It is from the ba.se of the leaf stalk in the majority of 

 cases that every extension of the plant arises. Very 

 many plants can, under certain conditions, give rise to 

 fresh plants by means of their leaves, whilst some of 

 the lowlier forms of green vegetable life never increase 

 in any other way than by a process of leaf cell exten- 

 sion. Under these circumstances it will be admitted 

 that we shall not be far wrong in regarding the leaf as 

 the most important organ of the plant. 



Our Own General Election. 



TnK results of our call for opinions has not developed any such 

 remarkable surprises as those in the political world. 



Though our thanks are due to many hundreds of readers who 

 have kindly returned the Ballot Cards duly filled in, we are slightly 

 disappointed that a larger proportion of our electorate did not 

 record their votes. It may be due to laxity in the canvassing ; 

 but, perhaps, the fact is not of importance, since it must be presu- 

 med, as in the political elections, that those who did not poll are 

 contented to leave the conduct of aft'airs in the hands of those in 

 authority, without any very special wishes as to future policy. 



The cards must be carefully gone through before we can definitely 

 decide on any change of policy : but a cursory glance at them 

 seems to show that most readers are quite satisfied with the 

 arrangements now in vogue. 



The Interior of the 

 Ea^th. 



Radioactivity and Volcanicity. 



In an article on " The Interior of the Earth," %yhich 

 appeared in " Knowledge .'XND Scientii-ic N'ews " for 

 last month, it is stated : — 



"The liquid substratum consists of a mixture 

 of juud rock and a dissolved gas (in all probability 

 hydrogen)." 



It may assist the theory somewhat if an explanation 

 were offered for the existence of hydrogen at such low 

 depths and so intimately associated with the fused rock. 



Among the many and wonderful properties of the 

 radioactive elements, one of the most recently di.s- 

 covered is that these substances slowly effect the de- 

 composition of water into its constituent elements, 

 hydrogen and oxygen, in the exact proportions, by 

 voli(me, necessary fcr the re-formation of water. 



This discovery must be considered in conjunction 

 with two well-established facts, viz. : — 



(i.) Water is capable of percolating to very great 

 depths in the earth's crust — the evidence from hot 

 springs is a sufficient testimony to this. (In the vapours 

 from which, radioactive emanations are always present), 

 and 



(2.) Radioactive minerals are to be found in rocks, 

 which, although sometimes met with at the surface, 

 possess all tbecharacteristicsof ha vingadeep-seatedoiigip. 



It must follow, then, that the water, as it percolates 

 between the interstices in the rocks, or even between 

 the composing crystals (for it is very imperfectly under- 

 stood by wh.at means water can reach such depth.s), is 

 decomposed into hydrogen and oxygen. 



The characteristic property of the latter gas affords 

 a ready and sufficient explanation of the fact that little 

 or no free oxygen ever appears at the mouth of an 

 active volcano or e^er issues from the surface of a hot 

 spring. 



The suggestion may even aspire to explain the uni- 

 versal existence of oxygen in combination with all the 

 elements composing the earth's crust. 



With respect to the hydrogen, that which has been 

 liberated nearest to the surface of the earth may con- 

 ceivably make its way up again into the atmosphere; 

 that which became free at lower depths may find its 

 way to a point of weakness (such as would be offered 

 by a volcanic area), and make its escape in a more 

 sudden and disastrous manner; while the hydrogen that 

 was formed at the lowest depths, finding it impossible 

 to escape, owing to the pre.ssure above and other 

 causes, might possibly become incoroorated with the 

 rock in its vicinity in such a way as to supply the 

 dissolved gas which Fisher's theory requires. 



Fisher assumed the existence of a liquid substratum 

 (beneath the earth's crust), which is saturated with 

 gases, and, therefore, expansible. If the capacity of 

 molten rock for dissolving ga.scs is similar to the 

 solubility of certain ga.ses in water, then there would be 

 no tide in the substratum which would affect the level 

 of its surface or cause any rise or fall of the overlying 

 crust, which proves, what Fisher maintains, that there 

 arc no terrestrial tides. 



If it be admitted that the interior of the earth is either 

 molten throughout or liquid to a certain depth, and 

 then a solid nucleus, then it must follow that terrestrial 

 tides do exist. But the most wcightv evidence on this 

 point is not that supplied by actual observation, but by 

 calculation based on the above assumptions. B. I. 



