914 



SCIENCE. 



[N. S. Vol. V. No. 12a 



to the widespread Dakotan and Algonquian 

 stocks, and thus we find the aborigines 

 carrying the culture of this noted tropical 

 plant up to the northernmost limits of its 

 possible propagation. 



THE GROOVED STONE AXE. 



The statement is occasionally made in 

 lectures and articles on the American 

 aboriginal stone industry that the grooved 

 and polished axe, so common in our collec- 

 tions, is an artefact peculiar to our conti- 

 nent. 



It is true that in its special shape it is 

 rare in European collections. They have 

 the grooved maul or pounder, but not often 

 the polished axe with the groove running 

 round near the butt and with a sharpened 

 edge. A fine example, however, from south- 

 ern Italy, is described and figured by Dr. 

 Schoetensack in the ' Zeitschrift fiir Eth- 

 nologic ' (Heft I., p. 9, 1897). That it was 

 of local origin was proved by the kind of 

 stone of which it was made. He refers to 

 its similarity to American specimens, and 

 quotes other instances where they have 

 been found in the Old World. This is 

 but another example where the artificial 

 products of early man reveal striking simi- 

 larities in all continents. 



D. G. Brinton. 



Univeesity of Pennsylvania. 



NOTES ON INORGANIC CHEMISTRY. 

 In the last proceedings of the Chemical 

 Society (London), A. E. Munby describes 

 a Bunsen burner for acetylene which has 

 proved very satisfactory in his hands. The 

 tube is only five millimeters in diameter, or 

 a slightly wider tube may be used, provided 

 the mouth be curved inwards. With a 

 larger opening there is a tendency for the 

 flame to strike down. The gas jet is very 

 small, delivering only one foot of acetylene 

 per hour, under six inches of water pressure. 

 The air holes must be large, and with suffi- 



cient air a non-luminous flame is given. 

 The heating effect of the acetylene gas is 

 large, and seems to be about twice that of 

 coal gas. Mr. Munby suggests that the use 

 of such a convenient source of heat should 

 do much to stimulate research in country 

 places, where, coal gas not being procurable,, 

 heretofore no good source of heat was 

 available. 



In the same number Heycock and Ne- 

 ville, who have done so much to further 

 our knowledge of alloys, describe the study 

 of the sodium-gold alloys with the X-rays. 

 Sodium is much more transparent to the 

 rays than gold, and X-ray photographs of 

 thin sections of the alloy show its crystal- 

 line structure very clearlj\ The authors 

 point out that other alloys may be similarly 

 studied, and are at present engaged of 

 those of aluminum. It is possible that by 

 this method our knowledge of alloys may 

 be materially extended. 



In a graduating thesis at Washington and 

 Lee University, Mr. J. E. K. Cowan takes 

 up the question of the presence of tin in 

 canned goods, and his results confirm those 

 of previous investigators along this line. 

 He finds tin present in every can examined,, 

 including tomatoes, peaches, apricots and 

 sweet potatoes, in quantities of from 60 to 150 

 miligrams per kilo. Granting that this tin is 

 present in a form which can be acted upon in 

 the human system, and considering the large 

 consumption of canned goods, it seems to 

 follow that tin is less toxic than has been 

 supposed and that it cannot be a cumulative 

 poison. The maximum dose of tin is given 

 as half a grain of chlorid, but the amount 

 of tin corresponding to this might often be 

 taken into the system during a single meaL 

 Very few cases of supposed tin poisoning 

 from eating canned goods have been re- 

 ported, and it is probable there is little 

 danger from this source. In no instance- 

 did Mr. Cowan detect the presence of lead. 



