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HARDWICKE'S SCIENCE-GOSSIP. 



developed by the parent plants in that state, and I 

 presume we may also include our common green or 

 blue pea in the same class. Although these cotyledons 

 have not been exposed directly to light and air before 

 germinating, I think the presence of the chlorophyll 

 in their cases may be accounted for by the parent 

 plants depositing it in the cotyledons during their 

 development, in the same way as albumen and starchy 

 matters are formed and deposited by other plants in 

 various parts of their structure. It would be as easy 

 for a plant to form through the action of its leaves 

 chlorophyll for its cotyledons as to make, say, 

 albumen for them, and in this way the theory of 

 light being necessary for the formation of chlorophyll 

 would still hold good. But in the melon seeds, the 



Fig. 142. — Tracing of a young plant found inside a yellow 

 Melon, Sept. iSth, 1890. Cotyledons quite green. 



cotyledons are white inside. Whence, then, came the 

 chlorophyll for the cotyledons of this seed which 

 germinated ? Although the outside of the melon was 

 pale yellow, would it be possible for any chlorophyll 

 to be distributed throughout the flesh or fluid of the 

 melon, yet in such small quantities as not to be 

 visible or give any distinct green colour, but still 

 sufficient to colour green the cotyledons of the young 

 plant when absorbed into them? We may in this 

 way find an explanation for the presence of chloro- 

 phyll. I merely make the suggestion as it seems to 

 me at the present moment the only way to account 

 for it, if we are still to believe light as being necessary 

 to the formation of chlorophyll. Otherwise we must 

 come to the conclusion that plants may become green 



in colour although shut off completely from light of 

 any kind whatever. But suppose we account for the 

 presence of chlorophyll as I have suggested, how are 

 we to get over the difficulty as to air? No air 

 could possibly get into the fruit, so far as I could see. 

 In all our botanical works we are taught that air is 

 as essential for germination as either light, heat, or 

 moisture, but no air could get inside the melon to 

 sustain its seed, unless what air may have occupied 

 its cavity would be sufficient for it. Perhaps some 

 of your readers may be able to explain these points 

 to which I have referred, as I am sure it will be both 

 interesting and instructive. 



J. Ballantyne. 



ASTRONOMICAL OBSERVATORIES AND 

 WHAT IS DONE THERE. 



By F. W. Levander, F.R.A.S., etc. 



THERE must be very few indeed of my readers 

 who have never heard of an astronomical 

 observatory, many may have seen one — they are 

 not very common ; but I suspect that only a 

 comparatively small number have ever been inside 

 one or have more than a vague notion of the work 

 done therein. Our National Observatory is so close 

 to the metropolis that many of the inhabitants of the 

 " little village " are acquainted with its outward 

 appearance ; but we are not all Londoners. Besides, 

 those who do go to Greenwich to look at the 

 observatory are obliged to content themselves with 

 gazing at the clock, the twenty-four hour dial of which, 

 being inserted in one of the walls, is visible to the 

 public, or getting some information as to the height 

 of the barometer, or comparing their linear measures 

 with the few copies of Imperial standards on the 

 outer wall. Their attention may, too, have been 

 called to the various domes, one or more of which, 

 or the great drum itself, may have a slit open to the 

 sky, and they may have been told that " astronomers 

 were at work," with which somewhat indefinite 

 statement they have gone away content. Nor, 

 indeed, would they be enabled to satisfy any innate 

 curiosity further, for without powerful credentials no 

 one is allowed within the observatory itself. The 

 stranger is, ordinarily speaking, no welcome guest 

 there. In some foreign countries it is much easier 

 to gain admittance to the interior of an observatory 

 than is the case in our own country, and it is, per- 

 haps, due in a considerable measure to this that 

 we find around us such a lamentable ignorance — I 

 speak advisedly, and from long experience — of even 

 the commonest facts respecting the heavenly bodies,, 

 not to mention those which concern our own earth. 

 The study of Nature, the inquiring into those causes 

 which are found to produce order out of apparent 

 disorder, the harmonious obedience to which is 

 erroneously referred to the laws of Nature, must 



