THE FARMER'S MAGAZINE. 



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claim their indulgeoce. He would, however, endeaTour to 

 open to them an interesting page in the book of Nature, and 

 would invite them to follow him while he traced the history of 

 a member of one of the most illustrious families in the world. 

 For surely, if they rightly applied that epithet to those among 

 conscious beings who efifected the largest amount of goad, they 

 might not improperly apply it also to a being which, though 

 unconscious, was perhaps productive of greater benefit to man- 

 kind than any other in existence. The cereal crops, as thpy all 

 knew, afforded food, in one shape or another, to almost every 

 living human being in Ihe world. The Esquimaux, who lived 

 principally upon whale blubber, diversified occasionally by train 

 oil thickened with sawdust, were perhaps almost the only race of 

 men who did not feed upon corn of some kind or other ; and 

 they, as a race, were said to be gradually declining and decaying. 

 If they went to the other end of the globe — to the burning plains 

 of India, or to that strange land where the British troops had 

 recently accomplished a great victory, and, as they all hoped, a 

 permanent peace, they would find tliat the inhabitants lived 

 almost entirely upon rice — one of the cereals. If they came 

 into more temperate regions they would find that one or other 

 of the many different members of this important family formed 

 Ihe staple food of the people. In Russia, the inhabitants sub- 

 sisted chiefly upon rye; in Spain, upon maize or Indian corn; 

 in England and other temperate regions upon wheat. These 

 corns, there was no doubt, were created at the same time at which 

 ' man himself was created. He was not saying anything extra- 

 ordinary when he said this, because, as they all knew, many of 

 the productions which they now found in their gardens and 

 orchards had varied very considerably from their original form. 

 If they saw, for example, the origin of their cabbage or brocoli, 

 they would hardly recognize it — so much had cultivation changed 

 its character, without, however, having at all altered it as a 

 species. So likewise with wheat there had been great variation, 

 but no essential change from its original form. There were per- 

 haps in the world from 59 to 60 different varieties ; in Europe 

 there were 14 or 15; while of British wheat there were five or 

 six vari«ties then lying on the table before him, which Mr. Francis 

 had been kind enough to lend him, and in which they would 

 observe, though there were, perhaps, some differences in the 

 character of the grain, there was no tendency whatever to diverge 

 from the general form of wheat. Of the history— the botanical 

 history— of the wheat plant, they had no very satisfactory account. 

 They were all aware that corn, by which, in all probability, 

 wheat was meant, was mentioned in the Book of Genesis ; and 

 wheat was distinctly mentioned in Exodus. There could be no 

 doubt that Egypt was the cradle of agriculture to the world, and 

 that its inhabitants cultivated wheat very extensively; indeed 

 some of it had come down from them to us directly in their 

 mummies. In modern times, M. Olivier, a French botanist, had 

 found it growing wild in Persia and on the banks of the Euphrates. 

 So much for its history. He would now enter upon what was 

 the more particular subject of his lecture, namely— the followicg 

 out of the history of an individual grain from its cradle to its 

 grave ; and in doing so, he hoped he should be able to suggest 

 some points which would be interesting as well as instructive. 

 He looked upon lectures of this kind in a somewhat different 

 light, peihaps, to many ; he held that they were bound not to 

 sacrifice the truth of science in their attempts to popularize it — 

 that they should b3 careful that the instruction which they con- 

 veyed, while it was put forward in an attractive and interesting 

 form, should not lose its character of soundness. If they did not 

 see carefully to this, they would be doing harm instead of good. 

 Sound science was as easy to teach as unsound, and, in his 

 opinion, if it was studied with proper care, was a great deal more 

 interesting. If they took up a grain of wheat, and examined it 

 carefully, they would find at the lower part of the back a small 

 white spot. This spot was the germ of the future plant, and if 

 it were placed under certain circumstances it would begin to 

 grow ; that is to say, its vitality would be called into action, and 



it would become a living being. What life was, it was impos- 

 sible to say; its definition was beyond the sphere of human 

 knowledge. Numerous attempts had been made to define it, but 

 all had failed. One of the most famous definitions was that of 

 the celebrated anatomist Beclard, who described life to be 

 " organization in action." There was no difficulty in under- 

 standing that definition, but the little grain before him declared 

 at once that it was not right. Because they might keep it for 

 hundreds— probably for even thousands of years —and its vitality, 

 though inactive, would not be extinct. Indeed, until last year, 

 it was believed that wheat which had been found in the Egyptian 

 mummies, where it had no doubt been lying for many thousands 

 of years, had grown, and produced fruit; but his friend. Pro- 

 fessor Henslow, had recently thrown some doubt upon this point, 

 and therefore he would not press it. However, there could be no 

 doubt that it might be kept in an inactive condition for hundreds 

 of years, and yet be alive all the time. But though life could 

 not be defined, it had certain properties by which it could always 

 and easily be recognized ; and this was quite sufficient for their 

 study of organized beings. The circumstances which were neces- 

 sary to excite this vitality in the case of the grain of wheat and 

 other seeds were three :— 1st, a certain amount of heat ; 2nd, a 

 certain amount of atmospheric air ; 3rd, moisture. The heat by 

 which vegetation was principally excited and supported was 

 derived principally from the sun. But the sun, though the prin- 

 cipal, was by no means the only, source of heat. It might sur- 

 prise many of his audience to hear that the stars also were a 

 source of heat, and a very considerable source too. M.Pouillet, 

 a French philosopher, had calculated the radiation of heat col- 

 lected from the stars, compared with tliat of the sun, to be in the 

 proportion of 8 to 10, and that if they were to withdraw from the 

 surface of the globe all the heat which was derived from the 

 stars every living being upon the face of the earth would die. A 

 good deal might be said about the heat which was generated 

 within the interior of the earth. Experiments of great interest 

 and importance were now being performed in Paris, with a view 

 of obtaining more accurate knowledge on this matter, some 

 account of which appeared in the Gardeners' Chronicle a few 

 weeks ago. Thermometers had been sunk fifty feet into the 

 ground, and eighty feet into a cave at Paris ; and It had been 

 found that at the former depth there was a temperature which 

 only varied 3J° from one end of the year to the other, the tem- 

 perature being that of the air in which we live. At a depth of 

 ten feet the variation was of some 15° or 20°, and so on in pro- 

 portion. From these sources of heat combined there was always 

 enough in the soil for purposes of germination. The second 

 condition he had named was a certain amount of atmospheric 

 air. Atmospheric air, as they knew, was composed of certain 

 proportions of oxygen and nitrogen gas, with a much smaller 

 proportion of carbonic acid gas. This condition was permanent 

 and unchangeable. If they went to the top of the highest moun- 

 tain, or into the deepest valley, they would find the proportion 

 always the same— nay, more, a bottle of air which was found at 

 Pompeii, where it had lain for 1,800 years, was found, when 

 tested, to be exactly the same with that which is breathed by us 

 in the present day. It was the oxygen and carbonic acid gases 

 contained in the atmosphere which were chiefly required in the 

 germination and growth of plants. The third condition was 

 moisture ; and if these three conditions were applied to a grain 

 of wheat a very beautiful change took place. The chief part of 

 the bulk of the grain, which formed (he nourishment of the 

 embryo germ, consisted of two substances — common starch, and 

 a substance called gluten, which was nearly identical in chemical 

 composition with the substance of beef- steak. Neither starch 

 nor gluten were sufficiently soluble to be taken up and absorbed 

 by the young plant. In order, therefore, that they might become 

 available for its nourishment a chemical change took place, and 

 they might truly say, the seed died. Chemical decomposition, 

 which was a sign of death in any living thing, commenced in the 

 seed; one portion of it di«d in order that the other might be 

 quickened by its death. The change which thus look place was 



