March i6, 1905J 



NA TURE 



iifb\ 



ally decay, following an exponential law, and reaching half 

 value in forty years. But should the supply of emanation 

 in the future equal that in the past, the activity would 

 continue to increase in magnitude for the next hundred 

 years or so, until the supply and decay of radium D attained 

 a steady value. By that time radio-active experiments of a 

 delicate' nature would become difficult or impossible, as the 

 excited activity would rapidly discharge a gold-leaf electro- 

 scope. 



As the excited activity can be largely removed by acid, 

 the infection will at present cause no serious difficulty in 

 the majority of experiments on radio-activity, particularly 

 as the leak arising from it remains almost constant for 

 weeks or months. But when an electroscope with a very 

 small natural leak is required, it will be necessary to employ 

 fresh materials which have not been exposed to emanation. 



It appears desirable, in the case of laboratories not yet 

 infected, to keep radium in sealed vessels, and to blow the 

 emanation into the open air, and not into the rooms of the 

 laboratories. .\. .S. Eve. 



McGill University, Montreal, February 25. 



International Atomic Weights. 



Teie committees engaged in revising the tables of atomic 

 weights have now sent in their reports for 1905. The one 

 which appeared in the Berichtc is, of course, printed in 

 German, and that which has iust been circulated by the 

 Chemical Society is in English. 



Unfortunately, there is a want of uniformity in the naming 

 of the elements. Thus, in the English table we find 

 Glucinum, Gl, and Columbium, Cb, whereas in the German 

 table these elements are called Berylium, l^e, and Niobium, 

 Nb, respectively. Historically, no doubt, the names adopted 

 in the English table are more accurate. But in all text-books 

 the names and symbols employed in the tierman tables are 

 used, and have been for many years. 



It is difficult to see where the advantage in making the 

 change comes in, but, on the other hand, the disadvantages 

 of having two forms of nomenclature are obvious. 



K. .Moi.T.wo Perkin. 



London, March 8. 



The Planet Fortuna. 



Perhaps Airy quoted his Juvenal correctly, which 



" W. E. P." (p. 410) has failed to do. The poet was so 



well satisfied with the lines that he gives them twice, in 



his tenth and fourteenth satires. .And they run thus : — 



Nullum numen habes, si sit prudentia ; ncs te 



Nos facimus, Fortuna, deam creloque locamus. 



\V. T. 



The lines are variously quoted, and I cannot say what 

 version .Airy favoured. I believe he spoke from memory. 



COSTA RICA.' 



UP to 1540, Spain had reserved for the crown that 

 part of the territory of Veragua lying west of 

 the portion which had been granted to the heirs of 

 Columbus ; but, in that year, it was erected into a 

 province and called Costa Rica. It lies between 

 Nicaragua and the newly hatched, but featherless, 

 republic of PanainA, and is the smallest State of 

 the New World except Salvador. But it is one of 

 the most interesting, for, with Panamd, it forms 

 the connecting link between North and South 

 .\merica, not only physically but cthnologically. If 

 more were known of its ancient inhabitants, their 

 type, character, modes of life, habits and customs, 

 inter-tribal relations and forms of worship, and of 

 the ruins of ancient towns and burial places which 

 are silently dotted over the country, one might go 



1 '■ Archaological Researchesin Costa Rii 

 Royal Ethnological Museum in Stockholm. 

 (Stockholm: C. E. Fritzes, 190 1.) 



NO. 1846, VOL. 71] 



• By C. V. Hartman. The 



Pp. 195 ; mar-(-87 plates. 



far towards a solution of many vexed problems as to 

 the relation betwen early Mexican culture and that of 

 the Andean peoples — Chibchas of ancient Cundina- 

 marca, the Quitos and Canaris of Ecuador, the 

 Ouichuas and^AymarAs of the Inga empire. Much 

 of the data necessary to the formation of a just 

 conclusion arc buried on the slopes of the volcanoes 

 of Turrialba, Irazii, Barba and Poiis, and, in that 

 richest of fields for archaeological research, the 

 district lying between Lake Nicaragua and the Gijlf 

 of Nicoya on the Pacific coast of Costa Rica, while 

 the lowlands lying between Nicaragua and the 

 .\trato River of Colombia probably hide, under their 

 densely matted and almost impenetrable vegetation, 

 whatever evidences may exist of their occupation by 

 man, not only in the far-remote past, but even at 

 the date of the Spanish conquest. 



Hence we may welcome a scientific examination 

 of any section of the region outlined above, but 

 especially when the results are so carefully and 

 clearly set forth as they are in the work under 

 review — a large quarto volume richly illustrated. Its 

 publication, as well as the explorations of which it 

 treats, have been made at the expense of Mr. Ake 

 Sjogren, who has presented to the Royal Ethno- 

 logical Museum of Stockholm the valuable 

 archaeological collection with which Mr. Hartman 

 returned home. This gentleman, whose studies had 

 well equipped him for his task, proceeded to 

 Costa Rica in iSgy, where he remained more than- 

 a year in the territory once occupied by the Guetare 

 race. He commenced his researches in May (the 

 beginning of the rainy season) near the hacienda 

 of Mercedes, which is situated on the Guapiles 

 branch of the Costa Rica Railway, about fifty miles. 

 from Port Limon. 



" On the .(Xtlantic side, the moisture-laden atmo- 

 sphere and tropical heat have clothed the mountain 

 chains and the low swamp lands with eternal verdure, 

 with forests which are almost impenetrable, woven 

 together as thev are by lianas passing from tree to 

 tree. Neither aboriginal nor Spanish culture ever 

 made great inroads on the primeval forests of the 

 .\tlantic coast." 



Near Mercedes is a mound about 100 feet in 

 diameter at the base, 65 feet at the top, and 

 20 feet high. It is in a partially walled en- 

 closure, and" probably served as a platform on which 

 to erect statues facing the rising sun. The mound 

 may have been covered with a wooden structure 

 with a thatched roof, .'\mong the many human 

 figures found there, all mutilated, were two of life 

 size, one of which is notable as having ear plugs. 

 The chest and back are crossed by two thick ropes, 

 which pass over the shoulders and reach to the hips. 

 The right wrist supports a human head. The other 

 large statue has its hands resting on the hips. The 

 heads of both figures are covered with conical hats. 

 Rudely sculptured representations of alligators, pumas, 

 and other animals were found, but in fragments. 

 All of these, including the statues, were cut from 

 hard, basaltic lava. 



Mr. Hartman also examined the extensive burial 

 places of the ancient inhabitants of this district, and 

 opened a great number of cists. These varied in 

 dimensions, but it is apparent that they were rarely 

 intended for the interment of more than one person. 

 They had side and end walls of cobble stones, but 

 the "bottom and top were of slabs o' limestone. The 

 horizontal section of the cists was very irregular. 

 Only in one did he find traces of bone, but the " dark 

 soil 'near the bottom seemed to prove that the body 

 or bodies had been placed there." 



Manv vessels ' of burnt clay, sometimes roughly 



