FRAGMENTS OF SCIENCE. 



4 2 3 



chemical analysis was first made which in- 

 dicated that the ingot from which the shaft 

 had been forged was cast too hot ; that 

 the carbon was very unevenly distributed, 

 the center of the shaft containing fifty per 

 cent more than the portion near the circum- 

 ference ; and, finally, that the content of sul- 

 phur and phosphorus was three times greater 

 in the core than at the circumference, and 

 excessive in all parts of the mass. But the 

 most important and instructive results were 

 obtained in the microscopic examination of 

 sections. Micrometallography is a compara- 

 tively new science, which, however, already 

 promises to be of great practical value to the 

 metal-worker. The microscopical examina- 

 tion showed a bad structural arrangement of 

 the iron and steel " cells," especially in the 

 core. The phosphorus, as phosphide, was 

 distributed pretty generally, and the cohesion 

 between crystals rich in phosphide is very 

 faulty. The center of the shaft was riddled 

 with sulphide of iron, and was little tougher 

 than good gray pig iron. " It is almost cer- 

 tain that a number of sulphide flaws of the 

 interior gradually worked outward, along the 

 crystalline junctions of the fairly tough metal 

 outside, until under a vibratory shock of un- 

 usual force the whole mass ruptured." 



The Tsetse Fly. The few travelers whose 

 lot has led them through the lowlands of equa- 

 torial Africa have most of them reported the 

 tsetse fly (Glossina sp.) as one of the most 

 formidable impediments in the way of colo- 

 nization or even exploration of these regions. 

 Wild animals and human beings suffer only 

 temporary irritation from its attacks, but 

 domestic animals entering the fly districts 

 are seized in the course of a few days with 

 fever and wasting, and almost invariably die. 

 The tsetse is a dipter, having a pale yellow 

 abdomen and gray, striped thorax. It is rather 

 larger than the house fly. The mouth parts 

 form a powerful piercing beak. From an 

 account of a report on the tsetse-fly disease, 

 by Surgeon-Major David Bruce, published in 

 Nature, we learn that there has at last been 

 an attempt made to study the fly and its dis- 

 ease in a thorough and scientific manner. As 

 far back as 1870 a Mr. St. Vincent Erskine 

 endeavored to show that the disease was due 

 solely to change of grass and climate. Since 

 then several other travelers have stated their 



belief that the fly was not injurious, or, at 

 any rate, that the ill effects of its bite were 

 much exaggerated. At last the Natal Gov- 

 ernment has authorized Mr. Bruce to thor- 

 oughly investigate the tsetse-fly disease, and 

 his paper is the outcome of the first three 

 months' work. The results so far attained 

 seem to indicate not the action of a specific 

 virus, as was originally supposed, but the 

 transmission by the tsetse fly of a bacterium 

 or its products. The investigation is proceed- 

 ing along somewhat the same lines which Dr. 

 P. Manson is following in endeavoring to 

 trace the malaria plasmodium through the 

 mosquito. A similar relationship was traced 

 some years ago between Texas fever, a dis- 

 ease of cattle, in which certain parasitic 

 bodies were found in the red blood corpus- 

 cles, and the cattle ticks (Ixodidce). Among 

 the new facts brought to light by Dr. Bruce's 

 work, one of considerable importance is the 

 specific action which arsenic seems to have 

 on the disease; its administration causes a 

 reduction in temperature, a maintenance of 

 the normal number of red blood cells, and 

 a disappearance of the haematozoa from the 

 blood. 



Serum Therapy and Blood Brotherhood. 



The very ancient practice of the transfu- 

 sion of blood from one person to another, as 

 a means of cementing friendship, seems, in 

 the light of the modern serum treatment of 

 disease, to have been something more than 

 a purely sentimental operation. In a recent 

 letter to Nature, T. L. Patterson discusses 

 the probable value of such inoculations. He 

 thinks it very probable that a European in- 

 oculated with the blood or serum of a native 

 would be better able to resist the climatic 

 changes to which he is subjected in tropical 

 countries. "In other words, would blood 

 inoculation not set up in his system those 

 changes necessary to adapt him to the cli- 

 mate, and render him immune to the dis- 

 eases which are the result of the climate ? 

 The suggestion is based on the assumption 

 that the native is more healthy in his own 

 climate than any foreigner can be, and that 

 blood inoculation would acclimatize the lat- 

 ter at once. The advantages to be derived 

 from such a system are obvious. At pres- 

 ent, in central Africa, many missionaries and 

 pioneers are annually sacrificed to the cli- 



