FRAGMENTS OF SCIENCE. 



or jar of any kind, prevents even the least 

 damage to coal or roof, in striking contrast 

 to the action of explosives. The time occu- 

 pied is an important matter. It has so far 

 been about twelve minutes. This time in- 

 cludes placing the cartridge in the hole, con- 

 necting to the pump, getting down the coal, 

 withdrawing the cartridge from the hole, and 

 getting to the next place. The advantages 

 claimed for this process over the ordinary 

 blasting are (1) larger and stronger coal, 

 which means a better average price ; (2) non- 

 interference with the working of the pit, the 

 coal being got down whenever required ; (3) 

 no damage to roof; (4) no dust; (5) and ab- 

 solute safety from the dangers attending shot 

 firing. In previous machines of this sort 

 trouble has been had with the joints, but 

 it is stated that this one is free from that 

 fault. 



Timbnctoo and Jene. Mysterious and 

 romantic visions of wealth and gayety have 

 been associated for centuries with the name 

 of Timbuctoo. Of numerous travelers who 

 have ventured much to reach the city only a 

 few have succeeded. Thus, according to a 

 summary in the London Academy, Mungo 

 Park visited it in 1805, but was drowned in 

 the Niger shortly afterward. Major Laing 

 reached it in 1825, after a three years' ex- 

 pedition across the desert, but was murdered 

 on leaving it. Ren6 Caillie' found it about 

 the same time, and wrote a book about it. 

 Davidson was murdered, and Richardson 

 died in the desert on the way thither. Dr. 

 Bart found his way into the city, but never 

 stirred out of doors while there. Lenz visited 

 it and wrote a description of his adventure. 

 The late Joseph Thomson was planning a 

 visit to Timbuctoo when he died. Now the 

 Frenchman, Felix Dubois, has published one 

 of the best descriptions we have of the mys- 

 terious city. Its position on the edge of the 

 Desert of Sahara, and at the top of the great 

 bend of one of the largest and most con- 

 stantly navigable rivers of the earth, the 

 Niger, defines its importance. Yet M. Du- 

 bois found it not the greatest or most inter- 

 esting town in the region. It is surpassed 

 by Jene, whose name is echoed in the An- 

 glicised form Guinea. That city dates from 

 the seventh century ; was built, not by ne- 

 groes or negroids, but by the Songhis, who 



migrated from Egypt across the Soudan 

 more than twelve hundred years ago ; and 

 has wonderfully solid architecture of the 

 Egyptian order. The present inhabitants of 

 Jene, M. Dubois says, " resemble a palimp- 

 sest on which the first manuscript is dimly 

 decipherable. Their oral traditions, their 

 chronicles, and their dwellings all betray 

 their Nilotic fatherland." 



Three Masters in Science. We merely 

 mentioned, last month, the deaths of Prof. 

 Julius Sachs, the botanist, and Prof. Carl R. 

 Fresenius, the chemist. Prof. Sachs was 

 best known by his Text-book of Botany, 

 which is one of the standard works of the 

 science, of first authority. He was also au- 

 thor of the Experimental Physiologic, a work 

 of corresponding importance in its field, a 

 history of botany, and a collection of lectures. 

 He was born at Breslau, Germany, in 1832, 

 and died at Wurzburg, May 29th. His first 

 teacher was Purkinje. He taught at Prague, 

 Marandt, Chemnitz, and Poppelsdorf, near 

 Bonn, and was Professor of Botany at Frei- 

 burg and Wurzburg. The fame of Frese- 

 nius dates from so early a period in the cen- 

 tury that one would be almost inclined to 

 reckon him as of a past generation. He was 

 born at Frankfort on- the-Main in 1818, be- 

 gan the study of natural science very early, 

 entered the University of Bonn in 1840 and 

 that of Giessen a year later, and became 

 Professor of Chemistry, Physics, and Tech- 

 nology at the Agricultural Institute in Wies- 

 baden in 1845. He was identified with that 

 institution for the rest of his life. His best- 

 known works are the Qualitative Analysis 

 and the Quantitative Analysis, published in 

 1841 and 1846 respectively, which have 

 passed through very numerous editions and 

 have been translated into nearly every Euro- 

 pean language. M. Paul Schutzenberger, an 

 eminent French chemist, died June 26th, at 

 Mezy, France. He was born at Strasburg, 

 the son of a lawyer, in 1829 ; studied medi- 

 cine and then chemistry ; was made professor 

 of chemistry in the high scientific school at 

 Mulhouse ; then became adjunct director of 

 the chemical laboratory of the Sorbonne and 

 chief of chemical work in the College de 

 France. In 1876 he was named titular pro- 

 fessor of chemistry in this institution. For 

 many years he directed the physical and 



