July 4, 1884.] 



SCIENCE. 



15 



Hamburg powder company at Duneberg, is, however, 

 attracting the most attention on account of the high 

 initial velocities and low pressures which it has actu- 

 ally given in practice. The grains weigh about forty- 

 two grains, have a specific gravity of 1.86, and have 

 the hexagonal prismatic form so generally adopted 

 in Europe, with one canal. They have the color of 

 cocoa; and from this characteristic the powder has 

 become known as ' cocoa' powder. The reddish hue 

 seems to be clue to red-burned charcoal. Powders 

 heretofore made with red coal have been found to be 

 readily inflammable, and to explode with dangerous 

 brusqueness, producing high local pressures; and 

 hence care has been taken to select only well-burned 

 black coal for the manufacture of military gunpow- 

 ders. In spite of the fact that ' cocoa ' powder con- 

 tains red coal, it has been found by experiment, that 

 a grain of it burns slowly and with very slight defla- 

 gration, when ignited in the open air ; and that a mass 

 as great as fifty-five kilograms, when enclosed in a 

 wooden box and ignited, burned slowly, without ex- 

 ploding, and simply raised the cover of the box with- 

 out displacing it. This may be owing to the large 

 percentage of charcoal, the low percentage of sulphur, 

 and the high specific gravity ; but the slowness of 

 combustion is equally marked when a grain is crushed 

 to meal-powder ; and it is probable that there is a dif- 

 ference in the kind of charcoal, as well as in the quan- 

 tity.. In addition, it is claimed that this powder is 

 but slightly hygroscopic, and yields very little smoke. 

 The advantage of this last-mentioned property is 

 shown by the recent experience at Alexandria, where 

 the English were compelled from time to time to 

 cease firing, to allow the smoke from their guns to 

 clear away ; and in the Sudan, where the English 

 were blinded by the smoke, under which the enemy 

 crept upon them. On the other hand, it is stated that 

 'cocoa' powder fouls badly. 



With gunpowder, as with all mechanical mixtures, 

 the uniformity of the product depends largely upon 

 the thoroughness of the incorporation. To test gun- 

 powder for this most important condition, it is cus- 

 tomary to flash a quantity upon a plate of glass, and 

 to examine the residue; but the deliquescent and per- 

 ishable character of the deposit necessitates immedi- 

 ate examination, while long and frequent experience 

 with the test is required in order to enable one to 

 draw a proper conclusion from the observation. Col. 

 Chabrier has proposed the use of paper, colored blue 

 by starch and potassium iodide, upon which to make 

 the flash, the color being discharged by the combus- 

 tion of the powder. The test-papers of this process, 

 however, are also evanescent, and the trained mem- 

 ory must be relied upon in reaching a decision. The 

 writer has recently proposed the use of a paper col- 

 ored with Turnbull's blue, such as is produced in the 

 'blue-print' process of photography; since the color 

 of this paper is discharged by the action of such al- 

 kaline salts as are formed in the combustion of gun- 

 powder. For use, the paper is dampened ; the powder 

 is placed upon it in a uniform heap, and then flashed. 

 The paper is exposed to the action of the residue for 

 half a minute, and then washed in running water, 



and dried. The result is, that, wherever a globule 

 has rested, the color is bleached. It is believed that 

 these spots will be smaller and more uniformly dis- 

 tributed as the incorporation approaches complete- 

 ness, provided the state of the different samples tested 

 is otherwise the same. These test-papers can be pre- 

 served without change, and may be filed as standards 

 for comparison, or forwarded to experts for examina- 

 tion. Chas. E. Muxkoe. 



NOTICES OF ETHNOLOGIC PUBLICA- 

 TIONS. 



The ethnology of the Eskimo, better called Innuit 

 people, is to us of an ever-renewed interest, not only 

 on account of the researches around the arctic pole, 

 in the furtherance of which this race has been emi- 

 nently helpful, but also for the peculiar ethnographic 

 position of the people among the other American 

 nations. Dr. Franz Boas has discussed the present 

 seats of the Neitchillik-Eskimo, first seen by Sir John 

 Ross (1829-33), and recently visited by Lieut. Schwat- 

 ka, and illustrates his article by a topographic map. 1 

 Another article of singular interest, by Edward B. 

 Tyler, deals with " Old Scandinavian civilization 

 among the modern Eskimos," with two plates,' 2 and 

 contains a large amount of facts new to science. 

 Bering's Straits, considered as the ' bridge ' between 

 the two continents and hemispheres, necessarily 

 calls the attention of all ethnologists to the tribes 

 inhabiting both sides of it. The ethnographic rela- 

 tions of these are expounded with minute care by 

 Prof. G-. Gerland of the Strasburg university, in a 

 paper inscribed " Zur ethnographie des aussersten 

 nordostens von Asien." 3 The tribes on the Asiatic 

 side are described from the accounts given by the 

 latest travellers, and old errors concerning them are 

 refuted. 



Rev. J. Owen Dorsey, formerly missionary among 

 the Ponka Indians, and a specialist in the study of all 

 tribes and languages of the Dakotan family, has given 

 a lucid ' account of the war customs of the Osages ' 4 

 as the result of a visit to that tribe, made in 18S3. 

 These interesting war and hunting customs are chiefly 

 based upon the gentile or totem-clan system. The 

 rules observed in encamping and other military acts 

 were most rigidly and unalterably enforced, per- 

 haps more so than our own military regulations, and 

 through their archaic forms testify to a high antiquity. 

 Customs like these may be traced among all the war- 

 like tribes of the Mississippi plains, even at the present 

 time, when they are hedged in within the narrow 

 limits of Indian reservations. Numerous illustra- 

 tions facilitate a clearer understanding of the practices 

 described. 



Dr. W. J. Hoffman presents us a "Comparison of 

 Eskimo pictographs with those of other American 

 aborigines," 5 interspersing his article with numerous 



1 Zeitschr. gesellsch. erdk. Berlin, sviii. 222. 



2 Journ. anthrop. inst., 1SS4, 3-48. 



3 Zeitschr. gesellsch. erdk. Berlin, xviii. 194. 

 * Amer. nat., 1S84, 113. 



5 Trans, anthrop. soc. Wash., ii. 12S. 



