18 



INTRODUCTION 



Private 



Workers 



made of such facilities as the laboratories afford, not only in the directions mentioned, 

 Water-supply but in hygienic work, more especially of course for Kliartouni. Thus, a prolonged 

 investigation on the proposed water-supply for this city taxed severely the resources 

 both of the chemical and the bacteriological departments and left but little spare time 

 for research. As will be seen, however, this water enquiry, which turned out to be one 

 of great interest and complexity, soon assumed the nature of a research which led, 

 I believe, to the satisfactory solution of an important and difficult problem. 



These are but a few examples of the purposes which the laboratories now serve. 

 The scope of the work and details regarding it will be considered immediately, but here 

 one would chronicle a new development, namely the advent of private workers who, at 

 their own charges, have spent a considerable time in Khartoum carrying out research 

 work in the laboratories and, for the sake of gaining experience in tropical work, kindly 

 assisting the Staff in routine and other work. Thus, during the winter 1908-9, 

 Dr. A. C. Stevenson uf the University College Hospital, London, was one of these 

 volunteers and he rendered good service by discovering coccidiosis in Sudanese goats, 

 an observation which enabled the veterinary officers to take measures for stamping out 

 the disease amongst infected herds. Dr. Stevenson also investigated the haematozoa and 

 intestinal protozoa of the common toad in Khartoum, and he contributes papers on both 

 these subjects to this Report. He has also kindly supplied the drawings illustrating 

 them. Dr. W. M. Aders, our other free-lance, was here at the same time as 

 Dr. Stevenson. In addition to helping us with his zoological knowledge he studied the 

 subject of hyper-parasitism, and contributes a paper on his researches into the 

 Herpetomonas parasite which he found in Aspoiujtypus viduatus, the Sudan melon bug. 



Since these gentlemen left, applications have been received fi-om an Italian Scientist, 

 an American Professor and a medical missionary resident in Persia, for permission to 

 study tropical medicine in the laboratories. Unfortunately, we have little spare room at 

 our disposal, but in one of these eases arrangements have been made to grant the 

 request, and Professor E. F. MeCampbell of the Ohio State University, Columbus, will, 

 I hope, be our guest and fellow-worker during the winter of 1911—2, both in the main 

 laboratories and in the floating laboratory. 



Before proceeding briefly to outline the work accomplished in the different sections, 

 one has to record the fact that, at Mr. Wellcome's request, the distinguishing word 

 " Tropical " has been added to the title of the laboratories, and they will hereafter be known 

 as the Wellcome Tropical Eesearch Laboratories. As mentioned, the laboratory work has 

 so greatly increased, and the number of our outside contributors is on this occasion so 

 numerous, that it has been found advisable to split the Fourth Report into two volumes, 

 the first dealing with medical, the latter with general science. At the time of writing, 

 it is also hoped to bring out a Second Review Supplement more or less on the same Imes 

 as that issued as an appendix to our Third Report. We have received a good many letters 

 testifying to the utility of that publication and expressing a hope that another volume 

 would be forthcoming. Hence, both for our own sakes and for workers in the Sudan and 

 in other tropical countries, it seems advisable to make an effort to produce another 

 compilation of this kind. Indeed, it is intended to extend its scope to the whole subject 

 of tropical medicine so that it may be more generally useful. The difficulty, however, 

 will be to keep it within reasonable limits as regards size. Here we only consider the 

 present Volume — B, with suc-h t-oinuients as may seem desirable. 



" Tropical" 

 added to 

 title of the 

 Laboratories 



