Apeil 14, 1882.] 



KNOVv'L.EDGE « 



519 



Weather. — Beaufort Scale is, b. blue sky; c. detached clouds; 

 d. drizzling rain; f. fog; g. dark, gloomy; h. hail; 1. lightning; 

 m. misty (hazy); o. overcast; p. passing showers; q. squally ; r. 

 rain ; 8. snow ; t. thunder ; u. ugly, threatening ; v. visibility, unusual 

 transparency ; w. dew. 



CANALS ON THE PLANET MARS. 



IX a letter to the Times, Jlr. Webb says : — It has long been known 

 that the surface of the planet Mars is so mapped out into 

 brighter and darker portions as to suggest the idea of contineats 

 and oceans, and the analogy thus implied with the arrangements of 

 our own globe is strengthened by the existence of brilliant white 

 patches, as of snow or ice, situate at or near the planet's poles of 

 rotation, and varying in extent with its changing seasons, as well 

 as by occasional differences in outline or colouring, which may well 

 be explained by the supposition of a vaporous atmosphere. 



In the autumn of 1877 and spring of 1878, when the planet was 

 in a part of its orbit which presented its surface advantageously to 

 view, a number of minute, straight, black or dusky bands were 

 detected by Schiaparelli, traversing and subdividing the supposed 

 continents in various directions. These have been called from 

 their aspect "canals," though, of course, their scale entitles them 

 rather to the appellation of straits, or very long, narrow arms of 



the sea. A few of these had been previously seen by various 

 observers, but to the Italian astronomer belonged the credit of 

 developing and delineating thorn as a system. At the ensuing 

 return of the planet in 1879-80 they were again detected and 

 drawn by him, with very little difference. But during the course 

 of last January and February he has been so fortunate as to 

 jierceive the duplication of these dark streaks by the addition of 

 parallel lines of similar character and length in no fewer than 

 twenty instances, covering the equatorial region with a strange and 

 mysterious network, to which there is nothing even remotely 

 analogous on the earth, and which leads us at once to see how 

 premature have been our conclusions in this respect, and how far 

 we still are from any adequate conception of the real constitution 

 even of our nearest neighbour but one in the solar system. 



T. W. Webb. 



[I have thirty or forty tracings of views of Mars taken several 

 years ago by Mr. Dawes — " eagle-eyed Dawes " as he was aptly 

 named — in which, though he used but an 8-inch telescope, some of 

 the long narrow passages mentioned by Mr. Webb are shown. I 

 mention this, because it may serve to corroborate what otherwise 

 might seem improbable, the circumstance that Signer Schiaparelli 

 should have seen with his comparatively small telescope what has 

 escaped the attention of observers using such instruments as the 

 Herschelian reflectors, the three-feet reflector made by Mr. Common, 

 and the magnificent 26-inch refractor of Washington. Albeit until 

 observers with such instruments as these have distinctly seen what 

 Signor Schiaparelli has mapped, we must not too hastily assume 

 that these are real features of Mars. Mr. Nathaniel Green, whose 

 tine lithographs of Mars adorn a recent volume of the Memoirs of 

 the Astronomical Society, considers that these narrow passages are 

 due to an optical illusion which he has himself experienced. 



Should it be proved that the network of dark streaks has a 

 real existence, we should by no means be forced to believe that 

 Mars is a planet unlike our earth, but we might, perhaps, infer 

 that engineering works on a much greater scale than any which 

 exist on our globe have been carried on upon the surface of Mars. 

 The smaller force of Martian gravity would suggest that such works 

 would be conducted much more easily there than here, as I have 

 elsewhere shown. It would be rash, however, at present to specu- 

 late in this way. — Ed.] 



WERE THE EGYPTIANS AWARE OF THE 

 MOTION OF THE EARTH 1 



HAVING shown from their ancient hieroglyphical texts that the 

 KgyjJtians understood the true motion of our planet, it now 

 onl}- remains for us to see whether this fact is corroborated by the 

 accounts we have in classic authors of the opinions of the Egyptians 

 on astronomical subjects. In discussing the matter from this point 

 of view the greatest caution is necessary, because an ancient 

 \\Titer might assign to them an explanation of astronomical phe- 

 nomena they never really held, from misapprehension, or supposing 

 it is found in some philosopher's works who propounded a system 

 allied to the Copemican, he might have falsely asserted his theory 

 to have been derived from Egypt in order to gain for it a better 

 hearing. M. Le Page Renouf, in his Hibbert Lectures, seems 

 inclined to reject in many cases the assertions that certain Greek 

 philosophers had been educated in Egy^jt, even doubting whether 

 it was true that Pythagoras did so ; but his riews seem far too 

 sweeping when compared with the universal testimony of the 

 ancients, many of whose statements bear on the face of them 

 evidence of truthful impartiality. For instance, Seneca says : — 

 " Eudoxus first brought with him from Egypt into Greece a know- 

 ledge of the movements of the planets ; nevertheless, he makes no 

 mention of comets. Hence it follows that even the Egyptians, a 

 people more curious than any other in all matters of astronomy, 

 had occupied themselves but little with the study of these bodies. 

 At a later period Conon, a most accurate observer, drew up a 

 catalogue of the various eclipses of the sun observed by the 

 Egj-ptians, but makes no mention of comets, which he would hardly 

 have omitted if he had found any facts respecting them." 



It would be an easy task to show that in all cases where the 

 theories of the Greeks have approached most nearly to those we 

 now know to be correct, they were expounded by men who are dis- 

 tinctly said to have studied in Egypt ; but only a few of the most 

 important of those which strictly appertain to our subject can be 

 given.* Perhaps the most valuable remark of a Greek author is 



• See Wilkinson " Ancient Egyptians," vol. II., 316, and I., 447- 

 Also Humboldt, Cosmos II., 544, and 692, ed. Bohn. That Socrates 

 icas in Egypt is proved by a Greek inscription on an Egyptian 

 temple, in which a Greek student says he was there " 200 years 

 after the divine Socrates." 



