December 13, 1917] 



NATURE 



zg 



the gases dissolved in natural waters, the conclusion is 

 that water freely exposed to the air should, and does, 

 contain the proportion of gases of the air corresponding 

 with the temperature and saline content of the water, 

 provided these have not been recently changed, in 

 respect of oxygen, all the ascertained facts show that 

 if water is found to contain very much less of this gas 

 than the saturation-value for the particular tempera- 

 ture in question, a strong presumption is raised that 

 the water contains matter undergoing oxidation. Since, 

 however, the water may have recently fallen in tem- 

 perature, the deficiency of oxygen may be only xin 

 apparent one, due to the fact that equilibrium between 

 the atmospheric gases and the dissolved gases has 

 not yet been established under the new conditions. 

 In such cases, therefore, the point can only be settled 

 definitely by determining the nitrogen — the constituent 

 which, so far as is known, is not taken up chemically by 

 anything in the water. It appears that slow non-tidal 

 streams will give unpleasant signs of the presence of 

 decaying matter at much higher degrees of aeration 

 than deep streams with strong tidal currents. This is 

 probably due to a variety of causes, such as slowness 

 of downward diffusion in the less rapid streams, and 

 the accumulation of undisturbed mud which, ingfer- 

 menting, gives off gases that have but little oppor- 

 tunity of being absorbed in their passage upward 

 through the layer of relatively still and shallow water 

 of the slow non-tidal streams. No fewer than seventy- 

 six references are included in the bibliography of the 

 ■subject given by the author. 



The Engineering Experiment Station of the Uni- 

 versity of Illinois has published a brief report upon 

 experiments on the utilisation of pyrites occurring in 

 Illinois bituminous coal, drawn up by Mr. E. A. Hol- 

 brook. It appears that some of the Illinois coal seams 

 contain bands, nodules, or lenses of pyrites in con- 

 siderable quantity ; these are for the most part thrown 

 out in the course of getting the coal, and thrown back 

 into the goaf, whilst others are picked out at the 

 surface. The proportion of pyrites in the coal refuse 

 varies from 7^ to more than 40 per cent., and whilst 

 it carries too much carbonaceous matter and too little 

 sulphur to be available for sulphuric acid manufacture 

 without treatment, it is shown by these experiments that 

 by simple crushing, screening, and dressing by means 

 of jigs and tables, it is easy to get a product with 

 40 to 45 per cent, of sulphur, with a recovery of 80 per 

 cent, of the pyrites present. Details are given of the 

 plant proposed for this purpose and of its first cost, 

 whilst an estimate of the cost of operating a plant 

 capable of' treating 50 tons of crude pyrites in eight 

 hours shows a very reasonable working profit. It is 

 interesting to find that the possibility of recovering and 

 utilising this hitherto waste material is attracting 

 attention. 



The latest catalogue of Mr. F. Edwards, 83 High 

 Street, Marylebone, W.i (No. 379, "Drama and 

 Dramatic Art"), is not of very especial interest to 

 readers of Nature, but attention may be directed to 

 the following volumes on North American Indian 

 tribal customs : — "The ' Hako,' a Pawnee Ceremony," 

 A. C. Fletcher; "The Mountain Chant, a Navajo Cere- 

 mony," Matthews; "The Sioux Outbreak of 1890 and 

 Ghost Dance Religion," Mooney; "Ceremonial of 

 Haszelti Dailjis and Mythical Sand Painting of the 

 Navajo Indians," Stevenson; "Tusayan Flute and 

 Snake Ceremonies" and "Tusavan Snake Cere- 

 monies," Fewkes; "The Zuni Indians; their Mytho- 

 logy, Esoteric Societies, and Ceremonies," M. C. 

 Stevenson. 



Sir William Tilden has just completed his life of 

 the late Sir William Ramsay, and placed it in the 

 hands of Messrs. Macmillan and Co. for publication. 



NO. 25 II, VOL. too] 



OUR ASTRONOMICAL COLUMN. 

 Fall of a Meteorite in Perthshire.— On December 

 3, at 1. 15, what is stated to be a meteorite struck the 

 lodge at Keithick House, Coupar Angus, which is about 

 , twelve miles N.E, from Perth. In the Blairgowrie, 

 Coupar Angus, and Strathmore districts a noise was 

 Iieard resembling a peal of thunder, and at places more 

 remote sounds as of a distant explosion were audible. The 

 meteorite has been taken to Perth for proper examina- 

 tion and analysis. It appears to have been well seen 

 by an observer at Edinburgh during its flight. The 

 I time was i.io p.m., and the object descended at an 

 I inclination of about 12° from the vertical to the left, 

 \ and disappeared in about azimuth 4° W. of N., at an 

 estimated altitude of 30°. This agrees very nearly 

 with the required direction of a body falling at Coupar 

 Angus, which is in slightly W. azimuth from Edin- 

 burgh. 



Further information shows that three fragments of 

 the meteorite have been found, weighing 22^ lb. (which 

 penetrated the ground to a depth of 20 in.), 2^ lb. 

 (which entered the roof at Keithick Lodge, Coupar 

 Angus), and 2J lb. (found in a field at Carse Farm, 

 near Blairgowrie, 6 in. below the surface). These 

 pieces were distributed over a distance of six miles in 

 a S.E. to N.W. direction, and sufficiently prove the 

 direction of the meteor's motion. 



From the various observations, now about twelve 

 in number, of the luminous flight of the meteorite, it 

 appears probable that its radiant point was in about 

 302° + 24°. This position would correspond in direction 

 with the line of the fallen fragments from Keithick to 

 Essendy. The meteor seems to have passed over the 

 Firth of Tay, about four miles S.W. of Dundee, and 

 at a height of twenty-five miles, and to have entered 

 over the Scotch coast from the North Sea near Fife 

 Ness, but it is hoped that further observations will 

 enable more certain and exact conclusions to be ob- 

 tained. 



A large number of persons witnessed the luminous 

 flight of the object, and are sending to Mr. W. F. 

 Denning observations from which it is hoped to com- 

 pute the real path. The meteor was strikingly bril- 

 liant, though the sun shone at the time. 



Observations of Long-period Variables.— A valu- 

 able series of recent observations of twelve long-period 

 variable stars is recorded by M. Luizet, of the Lyons 

 Observatory, in the Journal des Observateurs, vol', ii.. 

 No. 2. Some of the results are collected in the follow- 

 ing table : — 



No. of No. of », ■ », „ . 



Star maxima minima '^^'^S?' ^' ^^S^- »' Period 



observed observed "maxima minima in days 



SS Draconis 9 10 Se-g-i Q'3-9-5 48-2 



V Urs. Min. 14 11 7-8-8-2 8-3-9I 72-1 

 RR Bootis 6 I 8-2-9-5 I2-6-I2-8 194-0 

 AFCygni 6 26-8 80 96-8 

 UU Draconis 9 8 8*8 loi Irregular 

 SV Cassiopeiae i 1 7"3-8-4 9-i-io-i 279-4 



The other stars observed were UV Draconis, V 

 Aquilae, SS Cygni, X Herculis, TZ Cassiopeise, and 



V Cephei. 



Messikk's Catalogue of Clusters and Nebul.^. — In 

 L' Astronomic for November, M. Camille Flammarion 

 gives the first instalment of a systematic review of the 

 103 clusters and nebulae which were included by Messier 

 in the earliest catalogue of such objects which was 

 compiled. M. Flammarion relates how he came into 

 possession of Messier's manuscript, containing detailed 

 remarks on each observation, through good fortune at 

 a second-hand bookstall, and he is thereby enabled to 

 give the original account of each object. Observations 

 commenced by M. Flammarion forty years ago. and 

 afterwards continued with the collaboration of M. 



