I30 



SCIENTIFIC NE^VS. 



[Feb. lo, i8 



HAYA POISON. 



FOR some time past chemists have been paying some 

 attention to the arrow poisons which are used by 

 the native tribes of Africa. Messrs. T. Christy and Co., 

 the well-known importers of foreign drugs, lately 

 received from Africa some fragments of arrow points 

 for examination, and they sent them to the eminent 

 toxicologist. Dr. L. Lewin, of Berlin. This chemist has 

 discovered in the fragments a new arrow poison called 

 Haya poison, with wonderful properties. In his report 

 just published Dr. Lewin states that he is of opinion that 

 the substance has been attached to the barb of an arrow, 

 as in some of the furrows he noticed a good deal of 

 iron-mould. When ground to powder it had neither 

 taste nor smell, but readily absorbed moisture from the 

 atmosphere. It was soluble in water. On filtering a 

 solution, there remained a residue containing flint and 

 mica, and having a gloss like mother-of-pearl. About 

 60 per cent, of a solid substance was extracted by 

 water. The solution of even the smallest particle, when 

 boiled with mineral salts, became yellow. Phosphoric 

 acid yielded from a strong acidulated, aqueous solution 

 of the poison, a flaky precipitate, which, when treated 

 with baryta, yielded a minute quantity of a golden- 

 brown substance, having a decided effect upon the eyes 

 of animals. Having often heard of an arrow poison 

 which produced insensibility. Dr. Lewin made experi- 

 ments to ascertain whether the Haya poison produced 

 anaesthesia of the cornea of the eye, and he was 

 astonished to notice this effect on several animals. The 

 cessation of local sensation took place later than by the 

 anaesthetic cocaine, whose remarkable properties were 

 lately described in our columns. The insensibility, how- 

 ever, lasted for eight or ten hours in the case of the 

 Haya poison, whereas cocaine deadens the feeling for 

 only three minutes. The application produced a passing 

 irritation on the eye. He injected a concentrated solu- 

 tion of the poison in water into a frog : gradually the 

 pulsations of its heart decreased from 30 to 8 per 

 minute, with paralysis of the extremities. In small 

 dogs the effect was very striking ; the respirations after 

 about half an hour, became very rapid, with pauses 

 of short duration ; the head began to droop, saliva 

 flowed freely from the mouth ; peculiar convulsions fol- 

 lowed, during which the head was drawn close up to the 

 body, and the eyes were convulsively closed. When 

 this solution was injected under the skin of a pigeon, it 

 produced constant vomiting, frequent evacuations, pro- 

 tracted breathing, convulsions and death. But when it 

 was given to a pigeon by the beak, even a large dose 

 only produced vomiting and diarrhcea. In the former 

 <:ase half a grain was fatal, in the latter three and a half 

 grains had no fatal effect. Dr. Lewin concludes from 

 his experiments that the Haya poison may safely be 

 classified with the African poisons already known. The 

 effects of it reminded him very much of those he had 

 observed with the poison of the Somali, the so-called 

 Ouabaio, and the effects of the latter resembled the in- 

 toxication produced by the sassy bark, which, thirteen 

 years previously, he had worked upon. It was not, 

 however, known that the sassy bark contained the prin- 

 ciples of a local anaesthetic character, like the Haya 

 poisoa A solution of one in a thousand of the Haya 

 poison produced a deadening of the feeling in the front 

 part of the eye in cats, dogs, guinea-pigs, and other 

 animals, the pupil remaining imchanged for many hours. 



When the solution was injected under the skin of a 

 guinea-pig, the insensibility of the part treated was so' 

 great that Dr. Lewin was able to cut down as far as the 

 muscles without any discomfort to that most sensitive 

 animal. The quantity supplied to Dr. Lewin by the 

 Messrs. Christy was too small for the continuance of his 

 experiments : but a fresh supply will doubtless enable 

 him to discover some remarkable properties, which may- 

 make the Haya poison even more valuable than cocaine 

 for operations in surgery. 



THE JET INDUSTRY. 



THE neighbourhood of Whitby has long been cele- 

 brated for the manufacture of ornaments of jet, 

 the produce of the immediate neighbourhood. This- 

 mineral is found in a lower bed of the upper lias forma- 

 tion, and is found from about nine miles south of Whitby 

 to Boulby, and again to about a similar distance to the 

 north. The workings in the cliffs are now almost given 

 up, and the chief supply is now drawn from the Cleve- 

 land hills, especially at Hilsdale, near Broughton, where- 

 several mines are now open. 



There are two varieties of jet, the hard and the soft. 

 The former, which is much preferred, is found in layers,, 

 which vary greatly in extent and thickness. The largest 

 known specimen measured 6 feet 4 inches in length, 5 

 inches in width, and I5 inch in thickness, the weight 

 being 11 lbs. Hard jet varies in price from 4s. to 21s. 

 per lb., whilst soft jet is worth only from 5s. to 30s. per 

 stone weight. The demand for the soft quality has 

 almost ceased, since certain artificial substitutes have 

 come into use, and a quantity of jet is now imported from 

 Spain. Spanish jet is an inferior article, as it neither 

 bears the action of the weather nor that of friction as 

 well as the English quality. 



The jet industry has certainly afforded employment 

 at Whitby since 1598. But it was probably used for 

 ornamental purposes by the Romans. In the flourish- 

 ing times of the trade the annual yield of the raw 

 material was valued at _;^20,ooo, and no fewer than 500 

 men, women, and children were employed in the Whitby 

 district in the manufacture of jet trinkets. In i860 the 

 jet-trade of Whitby realised ^45,000, which by 1873; 

 had been more than doubled. Now, however, jet, like 

 many other articles of British production, is no longer 

 " in fashion." We may hope, however, that the "fickle 

 goddess " will some day relent and again sanction the 

 use of this mineral. 



The first step in working jet is generally to remove 

 the outer layer with a chisel. The pieces are then sawn 

 up into sizes according to the articles to be produced. 

 On these pieces the intended pattern is marked with a 

 steel point, the waste portions are cut away, the article 

 brought more exactly to shape by carving, turning, or 

 grinding on emery wheels, and finally polished by fric- 

 tion on list wheels, or boards covered with hide, with 

 the aid of a little rouge. 



Concerning the nature and origin of jet, some little 

 controversy has taken place. It is generally, however, 

 supposed to have been in a fluid or semi-fluid state, as 

 sometimes it is found enclosing wood, the scales of fishes^, 

 water-worn quartz, pebbles, and even angular fragments 

 of quartz-rock. 



