264 



NA TURE 



[December 30, 1909 



on human trypanosomiasis in north-eastern Rhodesia and 

 Nyasaland, and on trypanosomiasis of domestic stock in 

 north-eastern Rhodesia. The reports contain much valu- 

 able information concerning the habits and occurrence of 

 the species of Glossina and other biting flies, the various 

 types of trypanosomes (illustrated by photomicrographs) 

 met with in the blood of diseased domestic animals, and 

 other important points, and the question of prophylactic 

 measures against trypanosomiasis is discussed both for 

 human beings and animals. 



In another memoir Messrs. BreinI and Nierenstein give 

 an account of their biochemical and therapeutical studies 

 on trypanosomiasis. After a detailed account of their 



observations on experimental trypanosomiasis, the treat- 

 ment of infections with different pathogenic trypanosomes, 

 and the mechanism of the therapeutical action of various 

 trypanocidal compounds," they raise the question, "When 

 can an animal be considered to be cured?" No very 

 definite answer is given, however, to this question, and it 

 IS concluded that " the general condition of experimental 

 animals influences to a large extent the results obtained 

 in _ therapeutical experiments." The memoir ends with a 

 brief discussion on the comparative value of experiments 

 on different laboratory animals. 



The two remaining memoirs are by Prof. John 

 Cardamatis, on sanitary measures and malaria epidemics 

 of Athens, and by H. B. Day and Prof. A. R. Ferguson 

 on a form of splenomegaly, with hepatic cirrhosis, endemic 

 in tgypt. Both memoirs are illustrated bv photographs. 



In the Annals of Tropical Medicine and Parasitoloiiy. 

 vol. IV., part IV., are published two reports of the 

 expedition of the Liverpool School of Tropical Medicine 

 to Jamaica. The first of these reports is bv Mr. Robert 

 Newstead, on the ticks and other blood-suckiiig Arthropoda 

 of Jamaica. The author gives most interesting bionomical 

 notes, as well as systematic descriptions, of these pests 

 and suggests measures to be taken for the extermination 

 I ;■ } '^ "^°^^ ^'^''^•^ enemies of ticks were found 

 to be birds, especially the tinkling grackle (Ouiscahis 

 crassirostns), the parrot-billed blackbird (Cro(o/.;iaira ani), 

 and the domestic fowl. In the stomach of Crotophaga 

 there were also found specimens of the " green stink-bug " 

 {Loxa flavtcolhs), an observation of great bionomical 

 '"u"f •• .V?'^'' ^^'^ '"^'^'^f' '"^""Sli possessed of an odour 

 which IS horribly offensive," has a protective green colora- 

 tion. _ I he second report is bv Dr. W. T. Prout on 

 malaria. After discussing the nature and etiologv of the 

 disease and its occurrence in Jamaica, the author gives an 

 account of anti-malarial measures and their effects in 

 Jamaica and e sewhere, and suggests practical means for 

 combating the disease. 



PRODUCTION AND UTILISATION OF 



MOLASSES. 

 'pHE production of molasses is an important factor in 



the cane-sugar industry, and has received a good 

 deal ot attention in sugar-growing countries. Molasses 

 constitute the thick mother liquor left after the sucrose 

 has crystallised out, and, no matter what artifice be 

 adopted, there is a point beyond which it seems impossible 

 to obtain any more crystals, the sugar being held back 

 by the foreign bodies present. Hertzfeld has shown that 

 the formation of beet-sugar molasses is due to the mineral 

 matter originally present in the juice, or added in the 

 liming process, reacting with the sucrose to form non- 

 crystallisable compounds. Prinsen Geerligs has proved that 

 similar compounds are formed in working up cane sugar. 

 I he problem is complicated here by the presence of 

 glucose, which reacts more readilv with the mineral sub- 

 stances than does sucrose. In this wav is explained the 

 definitely established fact that, the larger the proportion 

 ot glucose to mineral matter, the greater the recovery of 

 sugar IS likely to be. There appears also to be a phvsical 

 factor involved; gummy matter is alwavs present, which 

 apparently coats the small crystals and prevents their 

 growth. 



^ The whole subject is discussed verv fully in an 

 illuminating article in a recent issue of 'the Agricultural 

 News, one of the publications of the West Indian Depart- 

 ment of Agriculture. It is further pointed out that during 



NO. 2096, VOL. 82] 



the past season the muscovado molasses of Antigua and 

 Barbadoes, and to a lesser extent of other West Indian 

 islands, has obtained a remarkably high market price, 

 higher, indeed, than the value of the sucrose present. The 

 chief consumers seem to have been the fishermen and 

 lumbermen on the North American continent. There has 

 been a simultaneous rise in the market value of the 

 exhausted vacuum-pan molasses of Antigua. The problem 

 of storage, therefore, assumes considerable importance ; it 

 is complicated by certain bacterial changes which are very 

 liable to set in. But these changes are not inevitable, and 

 with greater care in the manufacture the " souring " which 

 so greatly reduces the market value can be to a large 

 extent avoided. The composition of the various grades of 

 molasses is given as follows : — 



Muscovado Centrifugalkd Centrifugalled 



mola»se^ first second molasses 



(Aniigua) molasses (exhaus.ed) 



percent. percent. percent. 



Sucrose ... 501055 ... 401060 ... 20 to 40 

 (Uucose ... 5,, Is ... 7 ,, 20 ... 15,, 40 

 Non-sugar ... 3 ,, 8 ... — ... — 



Ash 3 ,, S ... 3 ,, 6 ... 3 ,, 10 



Water 24,, 30 ... 25,, 28 ... 17,, 28 



The first molasses can be made to yield a further crop 

 of cane sugar by re-boiling, but the second molasses cannot, 

 and are therefore said to be exhausted. 



The problem in Hawaii is very different in character. 

 The molasses obtained there are not of the muscovado type, 

 and consequently have no commercial value as human food. 

 It is estimated that something like fifteen million gallons 

 are obtained annually, of which about ten millions are used 

 as food for stock. There is little doubt that this would be 

 the most economical way of utilising the remainder, but, 

 unfortunately, the number of stock kept on the islands is 

 insufficient for the purpose. Of the other twenty million 

 gallons some is burnt as fuel, some is put on the land as 

 fertiliser, and some is run into the sea and wasted. 

 Decided benefit has followed the use of molasses as 

 fertiliser in Mauritius, and there is some reason to suppose 

 that the sugar increased the amount of nitrogen fixation 

 in the soil ; in consequence, the manurial value is higher 

 than one would expect from a consideration merely of the 

 amount of nitrogen and mineral matter present. These 

 favourable results, however, are not obtained in H.iwaii, 

 and experiments have been instituted at the Experiment 

 Station of the Hawaiian Sugar-planters' Association to 

 find out whether molasses could profitably be converted 

 into alcohol. Something more than 50 per cent, of sugar 

 is present, of which 83 per cent, can be converted by 

 fermentation into alcohol. The effect of varying conditions 

 has been investigated and the native yeasts described. 



THE AUSTRALIAN ASSOCIATION FOR THE 



ADVANCEMENT OF SCIENCE. 

 T^HE .Australian Association for the Advancement of 

 Science held its inaugural meeting in Sydney in Sep- 

 tember, 1888, and met there again in 1898 ; in January, 

 1890, it visited Melbourne, and again in 1901 ; since then 

 sessions have been twice held at Adelaide, Hobart, and 

 Brisbane, and once at Christchurch and once at Dunedin, 

 in New Zealand ; its next meeting will be held in Sydney 

 in 1911. 



As a rule, the meetings have been held in the capitals 

 of the .'\ustralian States at intervals of ten years ; as the 

 inland towns like Bathurst and Ballarat become larger 

 and better able to provide the requisite meeting-rooms and 

 other accommodation, they will also be visited. 



One great disadvantage under which the association 

 suffers is the very great distances which the members have 

 to travel ; the nearest meeting-places are between 500 and 

 600 miles apart, so that members living in Brisbane, Mel- 

 bourne, and Hobart have to travel those distances to attend 

 a meeting in Sydney, and members from South Australia 

 and New Zealand have to travel about 1200 miles, and 

 those from Western Australia nearly 2500 miles ; when the 

 meeting is in New Zealand all the Australian members 

 have to undergo a sea voyage of about five days at least, 

 and some a longer one, with perhaps some hundreds of 

 miles of railway travelling in addition. 



