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The light was blnish, like that of the English glowworm. The Aus- 

 tralian glowworm shone with a copper coloured radiance. Similar 

 phenomena had been regarded by Linnaeus and others, as indica- 

 ting an absorption, and subsequent radiation of diffused light, he 

 might, without committing myself to this theory, point out a 

 direction in which there seemed room for profitable investigation. 

 There could be no doubt that light was largely utilized in vegetable 

 economy. In the absence of light the decomposition of carbonic 

 acid ceased. The juices of celery and endive changed their 

 character, and colour was no longer produced. It appeared to him 

 that we were justified in supposing that these functions were 

 entirely discharged by light itself, and that the office of the plant 

 was to expose the tissues under favourable circumstances. If this 

 were so, an investigation of those conditions ought to enable us to 

 make light do the same for us. As light produced all shades of 

 colour in plants, a naturally coloured photograph was a possible 

 production, and might be ultimately obtained, and as the character 

 of certain juices was entirely changed by light, we might find out 

 from plants the secret by which organic compounds, similar in 

 composition, but different in properties and appearance, might be 

 interchanged. It would be useless to refer to the countless organic 

 compounds produced directly by plant organism; to starch, 

 dextrine, mannite, gum, &c., &c. It was sufficient to remark that 

 these substances were produced without any visible mechanism, 

 and under circumstances apparently exactly similar, to show that 

 in the simplest plant was locked up a secret of chemical manipula- 

 tion to which at present we had not the slightest clue — but it was 

 within the scope of his present object to point out as a great 

 portion of plant work the conversion of gases into solid matter. 

 Those who had grown mustard and cress upon a piece of wet 

 flannel knew that a certain quantity of mould was produced. So, 

 on a larger scale, every plant took its substance from the 

 atmosphere and laid it fimdly on the soil, building up daily what 

 would be cainozoic strata when we ourselves were fossils. The whole 

 of our linen and canvas was thus woven out of thin air, for the flax 

 plant, after the thread fibres had been removed from it, presented 

 the same analysis as the soil from which it was taken. 



At the request of the Chairman (Mr. Haselwood), a vote of 

 thanks was awarded to Mr. Lomax for his instructive papei-. 



