January 28, 1898.] 



SCIENCE. 



127 



in the analysis of samples which had been 

 purified to an extreme degree and those in 

 which the purification had not been .car- 

 ried quite so far. Thus, no evidence was 

 found showing the presence of any other 

 element or any impurity in the nickel 

 bromid and cobalt bromid used. The fig- 

 ure obtained for the atomic weight of nickel 

 is 58.69, and for cobalt 58.99, and the re- 

 sults of former observations as to the 

 anomalous order of these elements in the 

 periodic system are confirmed. An ex- 

 planation of the anomaly is not forthcom- 

 ing, and the same may be said regarding 

 the atomic weight of tellurium. Further 

 work upon the atomic weights of nickel 

 and cobalt involving the use of other 

 compounds than the bromid are now in 

 progress in the Harvard laboratory. 



A KECENT number of the Journal of the 

 Society of Arts contains an extended article 

 by Thomas Bolas on arsenical poisoning by 

 wall papers, etc. After pointing out that 

 the work of Gasio and Emmerlinghas con- 

 clusively shown that certain moulds have 

 the power of living on arsenical paper and 

 forming volatile arsenic compounds, the 

 author points out that arsenic even in small 

 quantities is poisonous to these moulds and 

 that the throwing off of arsenic in a volatile 

 form may be an effort of nature to cast 

 out the poison. Further, the most dan- 

 gerous papers may be those which contain 

 mere traces of arsenic, as when a large 

 quantity is present the moulds themselves 

 could not live. He suggests that traces of 

 arsenic may come into wall papers from the 

 imperfect washing of the vessels used to 

 contain the more highly arsenical colors, 

 and states that dyed and printed fabrics 

 now very frequently contain traces of arse- 

 nic. He recommends the use of the pre- 

 cipitated borate of copper as a green pig- 

 ment to replace arsenical greens, as long 

 ago proposed by BoUey. In view of the 



present low price of boric acid, this pig- 

 ment could be used commercially. 



A NOTE in a recent number of the Chem- 

 ical JSfeivs by Percy A. E. Eichards calls 

 attention to the presence of zinc in a water 

 which, after being stored in a reservoir, was 

 conveyed to a private residence through a 

 galvanized iron pipe some two miles long. 

 The amount of zinc bicarbonate in the 

 water was 7.3 parts per 100,000 or 73 milli- 

 grammes per liter. In the following num- 

 ber of the same journal Dr. T. L. Phipson 

 makes note of thepresence of zinc in a sample 

 of water which was conveyed into the town 

 of Funchal, island of Madeira, through gal- 

 vanized iron pipes. Dr. Phipson remarks 

 that, ' as zinc is a metal whose compounds 

 have a noxious action upoa the economy, it 

 is evident that galvauized iron pipe cannot 

 be used with safety to supply water for 

 drinking.' It would seem probable that the 

 large amount of zinc in the water described 

 by Mr. Richards (more than half a grain 

 in a pint) would have a decided effect upon 

 the health, though zinc is probably far less 

 injurious than several other metals occa- 

 sionally present in drinking water. The 

 distance the water was conveyed and the 

 probability of its relatively slow passage 

 through the pipes would account for the 

 large quantity of zinc present.* Where 

 only short lengths of galvanized iron pipe 

 are used there would be far less danger, but 

 the subject deserves further study. 



Among recent articles on calcium carbid 

 and acetylene is one by Lunge and Ceder- 

 creutz in the Ztsch. Angew. Chemie on their 

 analysis. The gas from ordinary calcium 

 carbid contains up to four per cent, of im- 

 purities ; among them hydrogen sulfid and 

 phosphin are the most important. These 

 are very injurious, and the gasmay bepuri- 



* An account of a very similar case to that reported 

 by Mr. Richards is given in the London Lancet for 

 March 1, 1884, as occurring in the water supply of 

 the village of Cwmfelin, Wales. 



