Fuly 9, 1885 | 
NATURE 
25/5 
Leyte, as well as of the great island of Mindoro, to say this. We 
know from Montano’s explorations that they live in great 
numbers in Mindanao and elsewhere; but nevertheless, the 
Negrito puro sooner or later adopts the dress and customs of his 
Malay conqueror. All the efforts of the Spanish Government 
and of the Catholic missionaries tend to efface the peculiarities 
of the Negrito ; and the Professor therefore states that, before it 
is too late, some scientific traveller should visit Mindanao to 
study the Atas and Mamanuas thoroughly ; likewise an investi- 
gation of the Negritos of Panay and Negros is much to be 
desired. 
M. LE Monnier contributes to the last number of the 
Deutsche Rundschau fiir Geographic, &c., an article on the 
Island of Hainan, off the coast of China, to which some atten- 
tion was recently directed on account of the rumoured occupa- 
tion of it by the French. It has been known to the Chinese 
since I1O B.C., but it was not till the 13th century that it 
received its present name. From the earliest times to the 
present the aborigines, the Li, who inhabit the mountains in the 
centre, have maintained a struggle against the Chinese. It is 
eyen less known than Formosa, for no Europeans have travelled 
in it. One port, Kiungchow, has recently been opened to foreign 
trade, the north and south coasts have been surveyed, but there 
is no survey of the east coast. As to size, it is a little smaller 
than Formosa, and is larger than either Sicily or Sardinia. The 
centre is exceedingly mountainous, and from it rivers radiate in 
all directions to the sea. Ii is so near the mainland that its 
flora and fauna are in all respects continental. The direction of 
the mountain system is from south-west to north-east. Volcanoes 
have been examined there, but they appear to be now extinct. 
Earthquakes are frequent. As in Formosa, the population con- 
sists of three elements—the Chinese, the subjugated and the 
independent natives. Amongst the former are the Miaotsze, 
who have crossed over the narrow strait from time to time from 
Kwangsi and We tern Kwangtung, and have taken possession 
of some of the smaller hills. Their language is said to be similar 
to that of the Li; they are good husbandmen, and are on friendly 
terms with both the Li and the Chinese. The independent Li 
appear to be an aboriginal race which has been driven back to 
the hills by the Chinese immigrants. Information with regard 
to them is very scanty, but they appear to have a reddish skin 
and to be of small stature ; their language resembles that of the 
Miaotsze of the mainland. The women are tattooed after their 
marriage, and they paint their faces with indigo. The Li are 
expert hunters and shots; the weapons are bamboo bows and 
arrows and a short sword in a sheath. The main sources of 
information with regard to Hainan are a paper by the late Mr. 
Mayers in the Yowrnal of the North China Asiatic Society 
(No. vii., 1873) ; one by Mr. Swinhoe, entitled ‘‘ Narrative of 
an Exploring Visit to Hainan,” in the same periodical (No. vii., 
1871-2); and a map of the Kwangtung Province, and other 
publications by Dr. F. Hirth. 
HERR GLASER, the Arabian traveller, has returned to Arabia 
to resume his explorations. This second journey is to be mainly 
geographical, but archzeology will also receive attention. Besides 
visits to Marib and Nejdran, Herr Glaser contemplates a long 
journey through the interior from Hadramant to Omaun, and a 
second across South Arabia. 
M. Baux, member of the Geographical Society of Paris, has 
been despatched on an ethnographical mission to China; and 
M. Guerné proceeds to Kiel to take part in the labours of the 
commission for the scientific examination of the German coasts. 
These missions are undertaken by direction of the Minister of 
Public Instruction of France. 
PROF. SEELSTRANG, of the University of Cordoba, has been 
appointed by the Argentine Government to superintend the 
publication of an atlas of the Republic, and a considerable sum 
has been appropriated for the work. It is to consist of twenty- 
seven parts, and four of these are already in hand. 
AT the last meeting of the Geographical Society of Paris, M. 
Alphonse Milne-Edwards in the chair, M. de Saint-Pol-Lias, 
who is now in Cochin China, presented a map of the upper 
course of the Red River, prepared by the Annamites. Another 
map of importance is that of the navigable water-ways of 
southern Indo-China, prepared by M. Rueff, who has established 
a company for navigating these waters. A letter was read from 
Jeddah stating that the collections of the unfortunate M. Huber, 
including his remarkable examples of Semitic epigraphy, were 
safe in the hands of the French Consul, and that the explorer’s 
remains were buried in Jeddah on May 27. 
THE last number (Band viii. Heft 2) of the Geographische 
latter, published by the Bremen Geographical Society, con- 
tains a study on the Congo region by Dr. Oppel, dealing with 
the scientific and economieal importance of this district. The 
paper is divided into two main sections: (1) The discovery and 
investigation of the Congo (a) between 1484 and 1872, (4) the 
systematic exploration since 1872; (2) The extent and bound- 
aries, geology, &c., of the Congo region. Prof. Seelstrang 
writes on the Argentine province of Buenos Ayres, its geo- 
graphy, fauna, flora, climate, inhabitants, trade, industry, &c., 
in short, a kind of encyclopzedic article on the province. 
Another paper on South American geography, or rather geology, 
is thac by Dr. von Thering on the Lagoa dos Patos, in the. 
province of Rio Grande do Sul, the largest lake in Brazil This 
is accompanied by a map of the extent of the sea in the province 
at the beginning of the alluvial epoch. Herr Zoller writes on the 
Batanga River; the number also contains a report of the late 
Geographen-tag at Hamburg. 
ON A RADIANT ENERGY RECORDER 
~ UNSHINE-RECORDERS may be divided into two classes, 
viz., those which roughly measure solar energy by the burn- 
ing of card and wood, and those which, by means of some 
photographic process, yield a record of the relative intensity of 
some more or less definite ray. The principle of the instrument 
which I am about to describe differs from those referred to in 
this respect—that it depends upon the evaporation of water 7 
vacuo, and its indications are therefore readily expressible in 
heat-units. 
The form of instrument with which I have sought to test the 
applicability of the method consists of a Wollaston’s cryophorus 
(of the form pictured in Ganot’s ‘‘ Physics,” p. 272, edition 
1872), in which the vertical tube and lower bulb are replaced by 
a simple glass tube graduated in cubic centimetres. The bulb 
containing the water to be evaporated is blackened by holding 
it in the smoke of burning camphor, and is then exposed to the 
sun, the rest of the apparatus being silvered or properly pro- 
tected by bright sheets of tin. At sunset the quantity of water 
which has distilled over can be read off on the graduated tube. 
An experiment on June 6 showed 1°8cc. to have passed over 
from a bulb of about 2 inches in diameter, and to have condensed 
in a narrow measuring tube between the hours of 10.40 and 
3.20. The instrument seems very sensitive, and may well find 
many applications. Ina suitable form of instrument the total nett 
solar energy gained by the blackened absorbing surface will be 
almost exactly represented in heat-units by multiplying the num- 
ber of cubic centimetres of water distilled by the latent heat of 
steam. To measure the loss of the earth’s radiation at night 
a similar instrument containing alcohol or some other liquid of 
low freezing-point might be employed. In either case, when a 
continuous time record is required, the graduated tube might be 
used as a cylindrical lens to condense light on photographic 
aper. 
The following are the more important conditions which the 
apparatus in a future form should probably fulfil :— 
(1) To present a constant and known absorbing surface to the 
sun. 
(2) To preserve a constant surface for evaporation which 
should be the same in the condenser, so that a reversal of the 
direction of distillation can take place under the same conditions 
when the black bulb is losing energy. 
(3) To give rise to the minimum of reflection and convection 
currents on the absorbing surface. 
(4) The apparatus should be so screened as to be at the tem- 
perature of the air apart from the gain of energy at the blackened 
surface. 
Some of these conditions seem likely to be more or less fulfilled 
in an apparatus consisting of two glass bulbs of equal diameter 
connected together by a tube bent through an angle of about 
150°, to bring the bulbs near together, and thus keep them in air 
of the same temperature. In the bulb containing the water to 
be evaporated, a black bulb might be fixed to absorb the solar 
radiation, whilst to the upper part of the second bulb should be 
sealed a graduated tube in which the distilled water might be 
measured by inclining the instrument. If metal globes were 
employed the connecting tube might be made to form the beam 
of a balance. 
