43S 



NA TURE 



[Skptemukr io, 1896 



reaching snow-coveved crexassed ire ; but, to our sur- 

 prise, we found that the apparent //Av field was a slope 

 of ice reaching to the col, or the mountain summit. We 

 naturally devoted much attention to a comparison of the 

 deposits accumulated by marine and land ice. Both lay 

 <lown glacial beds of very varied characters. We had 

 no ditificulty in finding cases of the formation of typical 

 boulder clay by land ice. We also kept in mind the 

 questions of the possibility of the uplift of material 

 through ice, and of the e.\istence of a differential 

 flow in glaciers. To take one case of the former : 

 in the moraine lying on the eastern face of the "Ivory 

 <".ate Glacier" we found many fragments of shells which 

 liad been lifted above the level of the old sea beaches, 

 whence they had been derived. This supplied us with 

 •one clear case of the uplift of material, and the sections 

 round the snout of this glacier left no doubt as to the 

 method by which this is effected. The proof of a dif- 

 ferential flow in glaciers is even more conclusive ; the 

 evidence of the e.xtent and importance of such move- 

 ments strikes us as the most impressive fact in the 

 glacial geology of Spitzbergen. Many of the glaciers 

 terminate with precipitous faces ; these show that the 

 layers of ice have the false-bedded arrangement that is 

 familiar from photographs of the Greenland glaciers. 

 Study of the sections shows that beds of englacial drift 

 are being uplifted or carried in a direction different from 

 that of the main movement of the ice. As we climbed 

 and sketched the face of the "Booming Glacier" at the 

 head of .Advent Vale, we could not but recall Mr. 

 Goodchild's paper on the "Glacial Phenomena of the 

 Eden \'alley " (1872) ; for we could see deposits of the 

 same characters as those he there describes being formed 

 by ice, acting in the way which he there assumes it 

 must have acted. 



The raising of beach material is also effected by the 

 stranding of bergs and floes upon the sea shore ; but the 

 range of this action is not very great. The Spitzbergen 

 walrus and seal hunters and fishermen agree that ice is 

 never forced on shore more than one hundred yards 

 inland, or to a height of over fifty feet. 



Marine glacial deposits occur in many parts of Spitz- 

 bergen ; but moraines formed in the sea differ from those 

 formed on land — by their shape, by the character of the 

 material, and its arrangement. 



It is, perhaps, unnecessary to add that the glaciation 

 of .Spitzlsergen was solely due to a local glaciation. We 

 found no evidence of any great polar ice cap. Had any 

 such have existed and overridden Spitzbergen from the 

 north, we ought to have seen its traces. On the contrary, 

 along the north coast the ice movement was from south 

 to north. J. W. Gregory. 



THE LAST DAY AND YEAR OF THE CEN- 

 TURY: REMARK'S ON TIME-RECKONING. 

 "T^HE late Astronomer Royal, Sir George Airy, once 

 -'- received a letter rec|uesting him to settle a dispute, 

 \vhich had arisen in some local debating society, as to 

 which would be the first day of the next century. His 

 reply was: "A very little consideration will suffice to 

 show that the first day of the twentieth century will be 

 January i, 1901." Simple as the matter seems, the fact 

 that it is occasionally brought into question, shows that 

 there is some little difficulty connected with it. Probably, 

 however, this is in a great measure due to the circumstance 

 that the actual figures indicating the century are changed 

 on January i, 1900, the day preceding being December 31, 

 1899. A century is a very definite word for an interval, 

 I'cspecting which there is no possible room for mistake or 

 difference of opinion. But the date of its ending depends 

 upon that of its beginning. Our double system of back- 

 ward and forward reckoning leads to a good deal of 



NO. \A02, VOL. 54] 



inconvenience. Only the other day 1 was reading in a 

 high-class scientific periodical (theycwv/i;/ of the Astro- 

 nomical Society of Wales), that the Athenian expedition 

 under Phocion to succour Byzantium (attacked by Philip 

 of Macedon) took place in B.C. 339, and that that was 

 now exactly 2235 years ago.' But it is evident that as 

 there was no year o, and H.c. i immediately preceded 

 .\.D. I, the interval from any date in a li.C. year to the 

 same in an a.d. year is found not by simply adding the 

 respective years, but by afterwards subtracting i from 

 this sum. Our reckoning supposes (« hat we know now 

 was not the case, but as an era the date does equally 

 well) that Christ was born at the end of B.c\ i. At the 

 end of A.D. I, therefore, one year had elapsed from that 

 event, at the end of A.D. 100, one century, and at the end 

 of 1900, nineteen centuries. 



Believing that our Lord was born in the autumn or 

 towards the end of B.C. 5, 1 once stated that our ordinary 

 reckoning was five, not four, years in error, because the 

 interval from a given date in B.C. 5 to the same in a.d. i 

 is five years. But I was properly pulled up for saying so, 

 because our reckoning supposes that Christ was born in 

 B.C. I, and B.C. 5 is the fourth year before that, so that if 

 we could now revert to the correct year of the Nativity, 

 the present year would be 1900, i.e. the nineteen Jiundredth 

 year after the birth of Christ. At its close nineteen cen- 

 turies from that event would be completed, and the 

 twentieth century commence with January i next year, 

 which would be called 1901. Here is where the apparent 

 difficulty comes in. Some people fancy that the vear 

 1900 means 1900 years after the birth of Christ ; but the 

 years are in fact ordinal, not cardinal, numbers, and the 

 century is completed, not at the beginning, but at the end 

 of that year. The mistake is of the same kind as if \ve 

 should conclude from a man being, for instance, in his 

 sixty-second year that he was sixty-two years old. A 

 recent writer in the Times points out that though the 

 same argument applies to the hours of the day, we do in 

 fact use cardinal numbers in this respect ; and when we 

 say, for instance, 4 o'clock in the afternoon, we mean that 

 four whole liours have passed since noon, whereas by 

 analogy with the number indicating the year, we might 

 mean the fourth hour. This of course is what the 

 Germans do, in speaking of time between two consecu- 

 tive hours, /lalb vier, for instance, with them meaning 

 half-past 3, or the fourth hour, half gone. But it would 

 be impossible to designate by half-/<rj7 4, for instance, 

 half an hour or thirty minutes' in the fifth hour or of hour 

 five ; and the French idiom equally necessitates counting 

 the portions of an hour from the hour as a cardinal 

 number. 



It is clear then that the year, as we call it, is an oi'dinal 

 number, and that 1900 years from the birth of Christ 

 (reckoning it as we do from the end of B.C. 1) will not be 

 completed until the end of December 31 in that year, the 

 twentieth century beginning with January i, 1901, that is 

 (to be exact), at the previous midnight, when the day 

 commences by civil reckoning. The writer referred to 

 above, truly says that in speaking of months of the year 

 and days of the week we also use ordinal numbers ; but 

 in these, when that method of designating them is used, 

 we actually say so, and call them the first or second, 

 &c., month or day. The year, on the other hand, is 

 always spoken of as a cardinal number ; but probably this 

 is on account of its number being I.irge. Had the 

 reckoning from the true or supposed date of the birth 

 of Christ been commenced in the first century, the years 

 w^ould doubtless have been called, like those of the reign 

 of a king or queen, the first, second, &c., or fiftieth, 

 sixtieth, year. In mentioning the hours of a day, the 

 matter becomes somewhat difterent, because we see them 



I The e.vpcdition re.iUy took place late in the .summer of li.c. 340, and there 

 m.ay be a misprint here. The article is in reference to a medal strucl: at 

 Byzantium, representing an occultation which occurred at the time, and is 

 the origin of the present Turkish standard. 



