356 



SCIENCE. 



[Vol. IX., No. 319 



ing of cotton cloth, etc., is attracting a great 

 deal of attention from both the scientific and 

 the practical side. A very favorable opinion 

 was lately expressed upon it at the Society of 

 chenaical industry. The process consists essen- 

 tially in electrolyzing a solution of magnesium 

 chloride, thus liberating the active agent of 

 chlorinated lime ; and, as it is easy to maintain the 

 solution at constant strength, it is found that the 

 consumption of chlorine is only one-half that 

 on the ordinary system. The fundamental indus- 

 trial equation of economy shows that the mechan- 

 ical work represented by 570-horse power spent 

 upon a dynamo-machine will produce the equiva- 

 lent of ten hundredweight of bleaching-powder 

 (' chloride of lime ') per hour, or a 50-horse-power 

 engine would give one ton per day of twenty-four 

 hours. 



Since Mr. Castner's paper upon his process for 

 manufacturing sodium and potassium was read at 

 the Franklin institute of Philadelphia (Oct. 12, 

 1886), several changes have been made in the 

 naethod of manufacture. These were recently 

 brought before the London section of the Society 

 of chemical industry by Mr. James Maclear. 

 With caustic soda at eleven pounds per ton, the 

 sodium produced costs less than twenty-tive cents 

 per pound, the cost of materials and fuel being 

 only seventeen cents. The steel crucibles em- 

 ployed have been used fifty, and probably can 

 be used a hundred and fifty or two hundred 

 times : hence the ' tear and wear' on them amounts 

 to not more than two cents per pound of sodi- 

 um. Cheap sodium, it need scarcely be men- 

 tioned, means cheap aluminium (by De villa's pro- 

 cess), which, with sodium at the above price, can 

 probably be produced at four dollars per pound, 

 or one-fourth its present value. 



The conditions affecting the distribution of 

 micro-organisms in the atmosphere were the sub- 

 ject of a paper at the Society of arts three nights 

 ago, by Dr. Percy F. Frankland, son of the dis- 

 tinguished chemist. The method of observation 

 was Hesse's, in which a given volume — usually 

 ten litres — of air is slowly drawn through short 

 wide tubes coated internally with a solid layer of 

 sterile gelatine-peptone. The maximum number 

 in the same place observed through the year, oc- 

 curred early in August. Elevation above ground, 

 and distance from human habitations, decreased 

 the number. In sea-air, for example, at one hun- 

 dred and twenty miles from land, there was only 

 one organism to ninety-three litres. In consider- 

 ing his paper, the author expressed a decided 

 opinion that it was the chemical side of bacteri- 

 ology which imperatively demanded attention at 

 present. The chairman. Prof . Burdon Sanderson, 



adjourned the discussion for a week, when it will 

 be opened by Dr. Alfred Carpenter. 



The government, which was recently approached 

 on the subject, has just agreed to make an annual 

 allowance of eight thousand dollars per year to 

 the youngest of English universities, the Victoria, 

 whose headquarters are at Owens college, Man- 

 chester. The success of this application will 

 encourage the promoters of government aid to 

 the university colleges throughout the country, 

 now languishing for want of funds. 



The Institution of naval architects, and the 

 scientific ship-building industry generally, have 

 just sustained a severe loss by the death of Mr. 

 William Denny of Dumbarton. Throughout his 

 too brief career, the influence upon him of Mr. 

 William Froude, F.R.S., was very marked. The 

 scientific department which he established in his 

 own yard at Dumbarton, on the Clyde, was the 

 first of its kind in a private ship-building yard, 

 and the fagade of its great experimental tank (300 

 feet by 33 feet, with 9 feet of water) was erected 

 to Mr. Froude's memory. Mr. Denny was the 

 first to use mild steel for the construction of 

 transatlantic steamers, in 1879. His most famous 

 paper probably was that on the difficulties of 

 speed calculation, in 1874-75, and his last was in 

 1884, on ' Cross-curves of stability.' In 1883 he 

 delivered the ' Watt anniversary lecture ' at 

 Greenock, on ' The speed and carrying of screw 

 steamers.' W. 



London, March 26. 



GEOGRAPHICAL NOTES. 

 Asia. 



The latest letters of the enterprising Frenchmen 

 MM. Capus and Bonvalot, who are trying to reach 

 India from Samarkand, are of considerable in- 

 terest. The latest are dated Jan. 13 and Feb. 

 33, 1887. They started from Samarkand for 

 Bokhara on Sept. 13. Near Samarkand they trav- 

 ersed the extensive plantations of General Korol- 

 kof, who has, by irrigation, brought under culti- 

 vation an extensive area of barren country on both 

 sides of the Kara Tepe. Over the difficult passes of 

 Takhta-Karacha and Lahore Murda the travellers 

 reached the valley of the Sangardak. All this dis- 

 trict is inhabited by the Uzbegs and Tajiks. After 

 a few days they reached the plain of Hissar. This 

 district produces rice in great quantities and of 

 exceptionally good quality. The town is very 

 unhealthy, and in summer the whole population 

 moves to Karatagh. The travellers then descended 

 the unexplored valley of the Kafirnahan to its 

 confluence with the Amu-Darya. In this valley, 



