SCIENCE. 



[Vol. XXI. No. 518 



SCIENCE: 



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HOW MANY ARCH^VN ROCK-GROUPS HAVE WE IN 

 GREAT BRITAIN? 



BY CH. CALLAWAY, D.SC , M A., F.Q.S., WELLINOTON, SHROPSBIBE, 

 ENGLAND. 



Recent geological research amongst the pre-Cambrian rocks of 

 North America, while it has settled some points, has unsettled 

 others. A generation ago the terms "Laurentian" and "Huron- 

 ian"' were thought to have a clear and definite application. At 

 that time, we in Great Britain knew of only one Archaean group, 

 called Hebriiiean or Lewisian, and supposed to be the equivalent 

 in time of the Laurentian. Later on, British geologists discov- 

 ered a second pre-Cambrian formation, the " Pebidian " of Dr. 

 Hicks, or "Uriconian" of the writer. This great volcanic sys- 

 tem bore many resemblances to the published descriptions of the 

 Huronian, and it was referred with more or less hesitation to that 

 gronp. Meanwhile, Dr. Sterry Hunt was creating more systems 

 in America. We heard of his " Noriau," " Moutalbian," "Ta- 

 conian," and "Keweenian," and every year we looked for new 

 worlds from his prolific brain. Unfortunately, subsequent research 

 in the United States and Canada has but very partially confirmed 

 Dr. Hunt's results, and even our faith in "Laurentian'" and 

 " Huronian " has been somewhat confused. "Huronian " appears 

 to be several things, and "Laurentian" in some localities is said 

 to be an intrusive granite. Nevertheless, it appears to be gen- 

 erally admitted that in North America there are gneisses and 

 granites which are older than any other rock-masses, and that in 

 the same region there are volcanic formations which are younger 

 than these crystallines, and more ancient than the Cambrian; so 

 that the old notions on "Laurentian" and "Huronian" remain 

 true in a general way. It would also seem that, North America 

 contains sedimentary rocks which are newer than the Huronian, 

 and are yet pre-Cambrian. Thus it would hardly be rash to 

 conclude that, on the western side of the Atlantic, there exist .it 

 least three Archaean rochgroups, a gneissie, a volcanic, and a 

 sedimentary, and that they succeed each other in the order here 

 given. Now it is interesting to remark that this description agrees 

 with the latest results of research in Great Britain. We have 

 first of all the gneisses and schists, which in Scotland are called 

 " Hebridean," and •' Malvernian" in England. We cannot say 

 that these formations are the exact equivalents of each other, and 

 it would certainly be rash to assert that they, or either of them, 

 can be correlated with any rock-massts the other side of the 

 Atlantic. Nevertheless, they are admitted to be the oldest rocks 

 in Britain, and, in the opinion of the writer, they are separated 

 by a considerable interval from the formation which comes next. 

 This great volcanic system holds the place originally assigned to 

 it in the Archaean series by Dr. Hicks and the writer. Its pre- 

 Cambrian age has been admitted by Sir A. Geikie, director gen- 

 eral of the Geological Survey of Great Britain and Ireland, so far 



as the Uriconian rocks of Shropshire are concerned ; but he assigns 

 the Pebidian of St. Davids to the base of the Cambrian. In the 

 opinion of the writer, the volcanic rocks of St. David's are truly 

 pre-Cambrian; so that the name "Pebidian," originally given to 

 them by Dr. Hicks, has priority over the more modem term 

 " Uriconian." These rocks are of wide distribution, being found 

 in North and South Wales, at Charnwood, n^ar Leicester, in 

 many parts of Shropshire, in the Malvern Hills, and probably at 

 Howth, near Dublin. Evidence has recently been collected of a 

 third pre-Cambrian system. Near Church Stretton, in Shropshire, 

 is a chain of hills, forming Longmynd, built up of conglom- 

 erates, sandstones, and elates. Murchison called these sediments 

 " Bottom Rocks," and he referred them to the Lower Cambrian. 

 This view has been adopted by the English Geological Survey, 

 and generally accepted. Recently, however, evidence has been 

 collected which makes it almost certain that this formation is of 

 pre-Cambrian age, and the present writer has given it the name 

 " Longmyndian." The true basal Cambrian, a band of quartzite, 

 occurs in close proximity to the Longmynd rocks, though not in 

 absolute contact; and it is incredible that the Longmyndian, 

 which IS some miles in vertical thickness, should be a mere sub- 

 division of the Cambrian, which is found in three of its four mem- 

 bers within a few miles to the east. It would seem, then, that 

 on both sides of the Atlantic, the Archaean (or pre-Cambrian) 

 series consists of (at least) three members, gneissie, volcanic, and 

 sedimentary, which follow each other in the same order, suggest- 

 ing a similarity of conditions in both areas in the successive 

 epochs of Archaean time. 



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Is the Maya Hieroglyphic Writing Phonetic ? 



In No. 505 of the Science, Professor Cyrus Thomas devotes a 

 few more pages to the problem of the Maya hieroglyphic writing. 

 "These," he says, "may perhaps be profitable to the subject, if 

 confined to an earnest endeavor to arrive at the truth." The 

 "additional evidence," introduced in this manner by Professor 

 Cyrus Thomas, he has seen fit to precede by some remarks 

 intended to invalidate the criticism I offered in this paper some 

 months ago {Science, Aug. 26). My answer to these remarks is 

 presented in the following lines, which, I trust, will also be profita- 

 ble to the subject, although I do not claim to be the only scientific 

 man that "earnestly endeavors to arrive at the truth." 



Professor Thomas is correct in stating that " a dot and two 

 crosses with a month- symbol form a date in the bottom line of Plate 

 49, Dresden Codex." Nevertheless, I firmly believe I can main- 

 tain that "there does not exist a numeral designation with crosses 

 between the dots." I have never seen it in the Codices. On the 

 other hand, I found, for instance, on the sides of the Stela J of 

 Copan (Maadsley, " Biologia Centrali Americani," PI. 69-70) that 

 the one dot of the numerals 1, 6, 11, and 16 always is framed by 

 two ornamental signs, but there is never an ornamental sign be- 

 tween the two dots of the numbers 2, 7, and 12. Compare the 

 Figs. 1-16 of the adjoined table. Moreover, I think, the analogy 

 between the two hieroglyphs. Figs 29 and 30 (of my former 

 paper), is obvious. Since in the one case the two dots and the 

 cross are a part of the hieroglyph and not a numeral, I hope, it will 

 not be a fault of veracity to believe the same in the other. 



Professor Thomas says I am not correct in stating that Fig. 30 

 (of my former paper) is the glyph he interpreted " moisture." 

 " True, the parts are similar," he says, •' but the details and sur- 

 roundings are different." In the adjoined table I repreduce the 

 Fig. 30 of my former paper by Fig. 17, and Professor Thomas's 

 moisture symbol by the Fig. 18. Certainly, the surroundings are 

 different. In Fig. 17 the hieroglyph is placed on a dish, in Fig. 

 18 on the hand. And there are wanting in Fig. 18 the two dots 

 and the cross that are seen in Fig. 17. But the parts are not 



