Nov. 4, 1880] 



NATURE 



At Fota, in the Cove of Cork, at Bamboo Island, they have 

 lived, fruited, and reproduced themselves for nearly thirty years, 

 and will probably continue to do so in the future, although no 

 Corcagian will be silly enough to believe in consequence thereof 

 that he is living in the climate of " torrid India." 



In fact, I adduced the evidence of Araiuaria Cuuninghami, 

 a !::ost <Mica/c sclf-rf:;istenng plant thermometer, in testimony of 

 the Kocene climate of Bournemouth ; and I find myself con- 

 fronted with Mr. Duncan's clumsy thermometer with not a single 

 fixed point on its scale, in the shape of an unspecified "clump of 

 ■bamboo canes." Let Mr. Duncan name the species included in 

 liis " clump," and I shall discuss the question fully with him. 



The facts stated in my letter, although by no means uncommon, 

 prove most convincingly to those who can appreciate them the 

 untenable nature of Lyell's theory of the cause of change of 

 geological climates. 



I must state my argument again : — 



1. In Eocene times groves of Moreton Bay pine lived, flourished, 

 and held their ground at Bournemouth against all comers. 



2. At the present time groves or forests of Moreton Bay pine 

 live, flaurish, and hold their ground at Moreton Bay against all 

 comers. 



3. Therefore the climate of Bournemouth in Eocene times was 

 similar to that of Moreton Bay at the present time. 



Geologists often make use of syllogisms much less conclusive 

 than the above, whicli is as good as any commonly used in 

 biological reasoning, such as it is. 



The present mean temperature of Bournemoulh is 20° F. 

 below what it was in Eocene times, which is equivalent to a 

 difference of latitude in the northern hemisphere between 31° N. 

 and 51° N. 



Sir Charles Lyell ' feebly attempts to get rid of scientific 

 conclusions as to temperature in two ways : — 



1. By a denial of the specific identity of the former and recent 

 species compared. 



2. By the unproved hypothesis of competing plants whose 

 superior vigour and not climatal conditions, account for the 

 ab-ence of the species which formerly flourished. 



In the case of the Moreton Bay pine I shall leave Mr. Gardner 

 to defend the asserted identity of species ; and I meet Sir 

 Charles Lyell's second supposition (which is really romance 

 writing, and not science) by the assertion that the Moreton Bay 

 pine, even if protected by man, will perish m any locality whose 

 ^ncan winter temperature falls below 57° F. 



The present mean January temperature of Bournemouth is 

 37"4 F., a temperature which would destroy in a single night a 

 whole forest of Moreton Bay pines. 



I was of course well aware that my argument from the former 

 existence of Moreton Bay pines at Bournemouth was only one of 

 many similar arguments that might be advanced from the former 

 existence of plants or corals in localities in which they do not 

 njw live. 



I know nothing, except from books, of the water temperature 

 ■necessary for the several species ot corals, nor do I know 

 whether any species of the tertiary corals found in England are 

 specifically identical with corals now living elsewhere. If Mr. 

 Duncan would give us precise information on this subject he 

 ■would throw most valuable light on geological climates. 



The corals would give us more information upon the question 

 than plants, because they would gauge for us the temperature of 

 the water in England ; that is to say, the temperature of the 

 former Gulf streams of the tertiary period, from which we could 

 calculate numerically the increase of solar radiation, necessary to 

 produce such former Gulf streams ; and possibly afterwards a 

 measure of geological time. 



I have elsewhere = shown that the fossil tertiary plant beds of 

 the Arctic regions show a falling off nf temperature similar to 

 that which has been proved at Bournemouth, of which the fol- 

 lowing is a summary : — 



Mcin annual 

 Lat. temperature in 



Mil 



Reduction 

 at present. 



Grinnell Land 

 Spitzbergen ... 

 Disco 



Si -44 

 78-00 

 70 00 



44-00 F. 

 35'30,, 

 36-00,, 



423 F. 

 51-8 „ 



E^octe" 



Eournemouth ... 50-50 ... 7o'75 ,> -.. 20-35,, 



I again assert that it is not possible to explain these facts 



^ " Principles," vol. i. p. 173 (twelfth edition). 

 " '- Lectures of Physical Geography," p. 344. 



without introducing causes differing in amount from those now 

 acting on our planet. Saml. Haughton 



Trinity College, Dublin, October 16 



The Yang-tse, the Yellow River, and the Pei-ho 



I READ with great interest the paper on the Yang-tse, &c., in 

 Nature, vol. xxii. p. 4S6. It seems to me that Mr. Guppy 

 has underestimated the quantity of water and sediment in these 

 nvers. As to the Yang-tse, this arises from the year 1S77 being 

 one of the driest in Western and Central China generally, and 

 thus the summer flood must have been one of the lowest on 

 record. Besides what w^e know of the character of the season, 

 an indirect proof of this can be had by comparing the rate of 

 discharge in April and at the time of highest flood, as given by 

 Mr. Guppy, with what is said by Mr. Oxenham, in his paper on 

 the inundations of the Yang-tse,^ According to the latter the 

 rise of water in April is not very large, the river not yet inun- 

 dating its banks, and being thirty feet below the summer 

 level. Thus in an average year the discharge in April would by 

 far not equal half of that of August, as found by Mr. Guppy, 

 but more probably be even below one-fifth of that of flood-time. 



On this account the data given by Mr. Guppy for the Yang-tse 

 are far below the average as to the discharge of water, and 

 probably even more so as to the amount of sediment, as the 

 proportion of sediment increases during high floods. In 1S77 

 the loess country of North- West China was subject to the severest 

 drought, so that the Han river, which generally contributes so 

 much to the sediment of the main river, must have been very 

 low in summer. 



As to the estimation of the discharge of water in the Pei-ho, it 

 is certainly much below the actual quantity, for Mr. Guppy has 

 taken only the months of December to March, i.e. months of 

 low w-ater. The monsoon character of the rains, i.e. the great 

 prevalence of summer over winter rains, is far more marked in 

 Northern China than in the middle part of that country, so that 

 the flood discharge of the rivers during and after the rains {i.e., 

 from July to October) must be enormously in excess over that of 

 winter. If, as Mr. Guppy says, the I'ei-ho rises only six feet at 

 Tien-tsin, this must be due to the banks being very low, so that 

 the river during flood-time inundates the plain to a very great 

 extent. 



My conclusion is this : — Mr. Guppy having underestimated 

 the di-charge of water of the Yang-tse and Pei-ho in the mean 

 of the year, this mu-t have been even more the case as to the 

 amount of sediment carried. Thus the relatively short time at 

 which he estimates that the surrounding seas will be filled by the 

 sediment carried by the great Chines : rivers has to be greatly 

 shortened, and if he thinks 36,000 years enough for the work, I 

 should estimate that 28,000 years would be sufficient. 



A. WOEIKOF 



Schpalernajo S, St. Petersburg, October 15 



Greek Fret 



In Nature, vol. xxii. pp. 513-14, there is a very interesting 



account of the development of ornament as illustrated by General 



Pitt Rivers' Anthropological Collection. I would venture to 



suggest that though in the majority of cases the Greel; fret jiattern 



Gateway at Labnah (Plate 19). 



was independently evolved in different countries from the 

 "double loop-coil," yet a study of the plates in Mr. father- 

 wood's beautiful work, "Views of Ancient Monuments in 

 Centml America" (1844), suggests to me the probability that 

 the builders of those remarkable structures arrived at the "Greek 

 pattern " through a degradation of the conventionalised human 

 I lycmrri. R. Geog. Soc, 1S75. 



