68 



NATURE 



[May 21, 1891 



discusses its indications. As a preliminary result, he finds that 

 two-syllable words have the vowels pronounced with equal 

 length and strength. Noteworthy differences appear in the 

 ■curve of a word according as it occurs in the middle or at the 

 end of a sentence. In the latter case, there is added to the 

 characteristic word curve, a terminal curve with declining pitch 

 and strength, which is nearly the same for different words, and 

 corresponds to the sinking of the voice before a pause. The 

 vowels and consonants show characteristic curves ; and notably 

 long wave-lengths occur with «, /, b, and d. The duration of 

 syllables varies between O'l and 0-5 second ; and between the 

 syllables of a word there are often pauses of 0-03 to 0-2 

 second. The shortest syllable / in itS , with rather slow pro- 

 nunciation, consisted of 22 vibrations ; yet the ear is capable 

 of not only hearing the tone, but of detecting fine shades and 

 differences in the mode of pronunciation. Further experiments 

 in this direction, with an improved apparatus, are contem- 

 plated. 



The Perak Government Gazette states that a portion of an 

 ethnographical collection formed by Signer G. B. Cerruti, in 

 the island of Nias, has been recently acquired by the Govern- 

 ment of Perak for the museum. Pulo Nias is one of a chain 

 of islands bordering the south-western coast of Sumatra. The 

 population is said to be numerous and of one race, though 

 divided into many tribes under independent chiefs. Head- 

 hunting is as common with them as it used to be in Borneo, and 

 most of the houses have skulls hung up in them. Their weapons 

 consist of iron-headed spears, mostly barbed, knives of two 

 patterns, somewhat resembling the Kadubong Achi, with shields 

 of two distinct types. No bows and arrows or blow-pipes seem 

 to be known, nor are throwing sticks applied to their spears ; 

 boats also are not used by them, though rafts are sometimes 

 made to cross th e rivers on. The ironwork of their weapons is 

 fashioned by themselves, and the upright double cylinder bellows 

 is used to supply wind to their forges — the same in every respect 

 as those used by the Semangs of Upper Perak, and the far away 

 Malagasy. Helmets of black ijoh fibre are worn, somewhat 

 similar to the cocoa-nut fibre ones of the Sandwich Islanders. 

 Woven body armour is in use, in the shape of thick coats made 

 of what appears to be the fibre of Hibiscus tiliacens. Buffalo 

 hide armour is also said to be used, but is not represented in 

 this collection. Attached to the sheaths of some of the knives 

 are four or five animals' teeth, such as tigers, rhinoceros, &c., 

 also a small carved wooden idol, and one or more bamboo boxes 

 containing stones. In those examined there were twelve pebbles 

 in each box. These stones are supposed to have been taken 

 from the spot on which a man had been slain. All these 

 charms are tied up into a bundle with red cloth, and bound with 

 string on the upper front part of the sheath of the knife. 



A COMPREHENSIVE Study of the influence of forests on the 

 daily variation of air-temperature has been recently made by 

 Prof Muttrich {Met. Zeits.), the data being from stations in 

 ■Germany and Austria. Inter alia, this influence is greater in 

 May to September or October than in the other months. In 

 pine and fir woods it rises gradually from January to a maximum 

 in August or September, then falls more quickly to a minimum 

 in December ; but in beech woods a minimum occurs in April, 

 then there is quick rise, till the maximum is reached in July. 

 The daily variation itself is greatest in May or June, both in 

 forest and open country. The influence of the forest is to lower 

 the maxima and raise the minima, and the former influence is in 

 most months greater than the latter ; in December and January, 

 and occasionally in neighbouring months, it is less. The in- 

 fluence on the maxima in summer is greatest in beech woods, 

 less in pine, and least in fir. The absolute value of the influence 

 in woods of a given kind of tree is affected by the degree of density 

 NO. I 125, VOL. 44] 



of the wood, being higher the denser the wood. The character 

 of the climate (oceanic or continental) also affects the results. 

 From daily observations in forest and open country, every two 

 hours in the second half of June, it appears that, soon after 

 5 a.m. and 8 p.m., the air-temperature in the wood was equal to 

 that in the open ; that the maximum was about o°'9 lower in 

 the wood, and the minimum o°"6 higher ; that in May to Sept- 

 ember the difference sometimes reached 2° 7 ; that the maxi- 

 mum in the wood occurred about half an hour later, and the 

 minimum a quarter of an hour earlier, than in the open ; and 

 that the daily mean air-temperature was about J° less in the 

 wood. 



The Revue des Sciences Naturelles de t Quest gives an account 

 of the life of Mathurin Rouault, one of the pioneers in the 

 geology of Brittany. Rouault was born in 1813, of a very poor 

 family. At the age of ten, while engaged as a shepherd, he 

 became interested in "stones" and "rocks," and began to 

 make a collection. By the death of a relative he obtained 

 possession of a small hairdresser's shop, where he worked on 

 Saturdays and Sundays, spending the rest of his time in hunt- 

 ing for rocks. Although Geoffrey Saint-Hilaire visited his 

 collection of specimens, and was much interested in them, nothing 

 would have been done for the poor young geologist — who lived 

 upon something like five centimes a day — if it had not been for 

 General de Tournemine, who, stationed with the garrison in 

 Rennes, had been attracted by him. It is said that one day he 

 went into the shop, and, seeing an antique pistol which 

 Rouault had bought for a few centimes to kill himself with, the 

 general remarked, "That is just the pistol I am after: I want 

 it for my collection." And without waiting for an answer he 

 took the pistol, and gave the young man 100 francs. M. 

 de Tournemine went still further. He revised a memoir which 

 the illiterate geologist had written. This was read in the 

 Academy of bciences, and met with so much success that the 

 author became well known. The town of Rennes gave him 

 800 francs a year to help him to live in Paris, and afterwards he 

 was appointed Director of the Geological Museum of Rennes. 

 But he was dismissed on account of quarrels with some unintelli- 

 gent bureaucrat, and died in 1881. Before his time only five or 

 six fossils were known in Brittany : afterwards they numbered 500 

 or 600. He spent two years or more in making up Trinuclem 

 Pongerardi out of over 2000 fragments. 



An important paper upon the atomic weight and position in 

 the periodic system of the rare element lanthanum is con- 

 tributed by Dr. Brauner, of Prague, late of the Owens College, 

 Manchester, to the current number of the Berichte. In his 

 recent work upon the reduction of oxides by metallic magnesium 

 Prof. Winkler advanced the view that lanthanum is a tetravalent 

 element of atomic weight 180, instead of, as has hitherto been 

 accepted, a trivalent element belonging to the boron vertical 

 group of the periodic system, with an atomic weight of 138 '5. 

 If lanthanum were indeed tetravalent with atomic weight 180, it 

 would probably be the missing element between ytterbium and 

 tantalum on the one hand, and cerium and thorium on the other. 

 Further, Prof. Winkler expresses the opinion that the old values 

 of Rammelsberg, 'Zschiesche, and Erk, for the equivalent of 

 lanthanum, are correct. These experimenters obtained the round 

 number 45 for the equivalent, and this number multiplied by 4 

 gives Prof. Winkler's suggested atomic weight 180. If, however, 

 multiplied by 3, the atomic weight 135 is arrived at, and Prof 

 Winkler argues that even if the element were trivalent its atomic 

 weight would not be 138*5 but 135. Against these views Dr. 

 Brauner brings forward the following experimental facts. In the 

 first place, Hillebrand (working under Bunsen) found the specific 

 heat of Bunsen's pure lanthanum to be o "04475. No impeach- 

 ment has ever been brought against this result, and Dr. Brauner 



