66 



SCIENCE. 



[Vol. XVIII. No. 443 



enough to take up fully one-half of the Colorado as it spreads 

 over the basin, and it would probably require from two to three 

 years for the balance to fill the hole up to level. At such times 

 as the river filled the basin to its level the flow to the Gulf of 

 California has been through a channel which begins at the lower 

 end of the basin, and makes a short cut directly south to the salt 

 water. This is called Hardy's Colorado, and it is usually simply 

 a dry channel or ditch. It may have been formed under circum- 

 stances similar to those existing at present. It is large enough to 

 accommodate the entire volume of the Colorado after the evapo- 

 ration which is sure to take place while the water is spread over 

 the basin. '' 



" Some idea of the terrible heat may be had from the evapora- 

 tion which takes place. If the basin were filled to the river level, 

 the lake would present a surface of about 1,600 square miles. 

 This would be lowered at the rate of six feet a year by evapora- 

 tion. The salt which is now being mined at Salton was deposited 

 in the valley by the previous evaporations. The original salt de- 

 posit from the water which was a part of the Gulf of California is 

 not responsible for all that is found there. The waters of the 

 Colorado are saline, for the river flows through beds of rock salt 

 at places many miles up from its mouth, and the successive de- 

 posits from the waters of this river as they have flooded the valley 

 and then dried up have added largely to the original deposit." 



OXFORD SUMMER MEETING OF UNIVERSITY EXTEN- 

 SION STUDENTS.' 



The process by which university extension is carried through- 

 out the country and made a vehicle for the further education of 

 the adult student is well known, and is gradually becoming more 

 and more appreciated in proportion as those who are responsible 

 for the method improve the lines on which it is carried out. The 

 machinery employed embraces lectures, classes, travelling libra- 

 ries, etc., but one element vitally necessary to the university stu- 

 dent is not supplied by these aids. This element is that of resi- 

 dence, and it was a happy suggestion on the part of the origina- 

 tors to propose that, for one month in the long vacation, arrange- 

 ments should be made by which those who have profited by being 

 brought into contact with a university lecture should enjoy the 

 additional advantage of being brought under the charm that 

 haunts the colleges and cloisters of Oxford and Cambridge. 



The Oxford summer meeting commences on July 31, and is 

 continued throughout the month of August ; but, for the benefit 

 of students who are unable to be present during so long a period, 

 the course is divided into two sections, the second commencing on 

 August 12. It has been found desirable to remove as far as possi- 

 ble the fragmentary and isolated character of the lectures given 

 at these meetings, and therefore, while the course will be complete 

 and independent in itself, it will also form the first part of a cycle 

 of study which for its full development will embrace a period of 

 four summers. 



That these lectures propose something more than to add 

 piquancy to an agreeable picnic will be shown from the following 

 slight sketch of the subjects treated — and treated by authorities 

 of acknowledged reputation. To take the lectures on natural 

 science first: in physiology, Mr. Poulton will discuss the recent 

 criticisms of Weismann's theory of heredity, and Mr. Gotch will 

 lecture on the functions of the heart. In chemistry, Professor 

 Odling lectures on the benzine ring, and under the supervision of 

 Mr. Marsh a course of practical chemistry will be conducted iu 

 the laboratory of the University Museum. In geology, a course 

 of practical instruction will be given by Professor Green and Mr. 

 Badger, to include excursions in the neighborhood of Oxford. A 

 class in practical astronomy will be welcomed at the university 

 observatory; while electricity finds an able exponent in Mr. G. J. 

 Burch. But the distinguishing feature of this meeting is the at- 

 tention given to agricultural science "designed for agricultural 

 audiences under county council schemes." This designation 

 seems somewhat vague, and it will be very interesting to see the 

 character of the audience attracted by this title. Four lectures 



1 Nature, July 16. 



are offered : the first entitled, ' ' The Application of Science to tke 

 Art of Agriculture." This description is sufficiently wide, but 

 does not indicate whether the lecture is intended as a sample of 

 those which state-aided board schools in agricultural districts 

 might well offer to lads who have passed through the successive 

 standards, or as one addressed to the sons of farmers, and supply 

 ing that form of instruction which it is the duty of agricultural 

 colleges to impart. Another lecture is ofifered on the management 

 of poultry. This is more definite and more hopeful; and when 

 we remember that the students who come up for these summer 

 meetings are, for the most part, ladies, who can well be supposed 

 to take an intelligent interest in this part of farming operations, 

 we must admit that the subject is well chosen. Manures of vari- 

 ous characters form the subject of the other two lectures, and will 

 be doubtless of a sufiBciently technical character. 



The literature and history lectures are of special interest, and 

 by the combination of many lecturers are made to cover with 

 great completeness the mediaeval period. Mr. Frederic Harrison 

 gives, as an inaugural lecture, a survey of the thirteenth contury, 

 and strikes the keynote of this section; while in the entire course, 

 which embraces some sixty lectures, we meet the names of Pro- 

 fessor Dicey, of Mr. York Powell, of Mr. Boas, and a host af 

 others, affording alike a sufficient guarantee for the excellence of 

 the work, ar(d a happy augury for the success of the meeting. 



THE FORESTS OF ZULULAND. 



An interesting and valuable report on the forests of Zululand, 

 by Colonel Cardew, has been issued by the British Colonial Office 

 as an official paper. Colonel Cardew's report, an abstract of which 

 we find in the Proceedings of the Royal Geographical Society for 

 July, deals in the first place with the existing state of the forests 

 of Zululand, then with the measures necessary to preserve them, 

 and lastly with the establishment of a staff necessary for the en- 

 forcement of the laws and regulations required to effect the better 

 preservation of these forests. As to their general distribution, 

 the forests of Zululand, Colonel Cardew says, may be conveniently 

 divided in the same manner as has been done by Mr. Fourcade, 

 assistant conservator of forests, in his report on the Natal forests ; 

 that is to say, into high timber forests, thorn bush, and coast 

 forests. The high timber forests are situated on the Nkandhla 

 and Qudeni ranges of mountains in the Nkandhla district; on the 

 Entumeni and Eshowe Hills and the Ungoye Mountains, in the 

 Eshowe district; on the slopes of the Ceza, and on the Useme, 

 Empembeni, Makowe, and other hills in the Ndwandwe district; 

 and on the VBombo Mountains, in the district of that name. The 

 thorn bush is to be found to a greater or less extent in all the river 

 valleys of Zululand, the timber increasing in size and the bush in 

 density on the lower parts of the rivers, especially in trhose of tke 

 Umkusi, and White and Black Umfolosi. It is very large and 

 dense in the country west of St. Lucia Lake. 



The coast forests are of no great extent, with the exception of 

 the Dukuduku; they grow in small patches along the streams and 

 rivers near the coast, and especially at their mouths, and also 

 cover the low gaud-hills which borrler the coasts of Zululand. 

 Tlie Dukuduku is situated on the north side of the lower Umfolosi 

 River in the district of that name. It is several miles in extent 

 and very dense, and was the place of retreat of the coast chiefs 

 during the disturbances of 1888. Dealing more particularly with 

 the distribution of the high timber forests. Colonel Cordew states 

 that the Qudeni forests clothe the slopes and spurs of the Qudeni 

 Mountain, a magnificent range rising to an altitude of some 4,500 

 to 5,000 feet, and situated between the Tugela and Insuzi Rivers. 

 The forests are of great extent. In the absence of a survey it Is 

 impossible to say what area they cover, but they clothe the south- 

 ern, eastern, and northern slopes of the mountain, and from their 

 extent and vastness are most imposing in appearance. They are 

 certainly the finest forests in Zululand, and are composed of the 

 most valuable timber, of the same nature and variety as that of 

 the high timber forests of Natal. Yellow wood, both onteniqua 

 and upright, abounds, and there is also every description of h;ird 

 wood, but from want of adequate protection these noble forests 

 have in many parts been ruthlessly destroyed. Woodcutters do 



