158 



SCIENCE. 



[Vol. XVIII. No 450 



term Cincinnati, and substituting Hudson River and TJtica slate. 

 The committee also supposed the Trenton was exposed on the 

 Ohio River twenty or twenty-five miles above the city. This opinion 

 was adopted by Professor Orton and others, but Professor James 

 concludes that there is no difference between the lowest beds ex- 

 posed on the Ohio at Cincinnati and the rocks at Point Pleasant. 

 He says the beds of the two localities cannot be placed in two 

 separate terranes unless an arbitrary line be drawn at some point 

 in the series. The paper is illustrated by two plates of views of 

 the strata at Point Pleasant, and at Ludlow, Ky., opposite Cin- 

 cinnati. 



— A German specialist, Dr. Cold, has recently pleaded for giv- 

 ing young people more sleep. A healthy infant sleeps most of the 

 time during the first weeks, and, in the early years, people are 

 disposed to let children sleep as much as they will. But from six 

 or seven, when school begins, there is a complete change. At the 

 age of ten or eleven the child sleeps only eight or nine hours, when 

 he needs at least ten or eleven, and as he grows older the time of 

 rest is shortened. Dr. Cold believes, according to Nature, that up 

 to twenty a youth needs nine hours' sleep, and an adult should 

 have eight or nine. With insufficient sleep, the nervous system, 

 and brain especially, not resting enough, and ceasing to work nor- 

 mally, we find exhaustion, excitability, and intellectual disorders 

 gradually taking the place of love of work, general well-being, 

 and the spirit of initiative. 



— An interesting paper upon the slow combustion of explosive 

 gas mixtures (of which Nature gives a brief abstract) is contributed 

 to the current number of Liebig's Annalen by Dr. Krause and 

 Professor Victor Meyer. The experiments described were made 

 with electrolytic mixtures of hydrogen and oxygen, and denotating 

 mixtures of carbon monoxidg~and oxjgen. The first experiment 

 consisted in heating in a bath of vapor of diphenvliimine (305°) a 

 denotatiug mixture of hydrogen and oxygen contained in a 

 U-shaped tube closed by mercury. The heating was continued 

 without intermission for a fortnight, ac the end of which time 

 very little gas remained, almost the whole having slowly combined 

 to form water. The experiment was then repeated in an apparatus 

 constructed entirely of glass, and in which the use of mercury 

 was avoided, except in a small manometer used to indicate the 

 pressui-e. It was then found that no trace of water was formed 

 at the temperature of diphenylamine vapor (305° C); at the tem- 

 perature of boiling sulphur (44'i°) the amount of combination was 

 exceedingly small; while at 518^, the boiling-point of phosphorus 

 pentasulphide, a considerable amount of combination occurred, 

 but no quantitative rule could be deduced. In all these experi- 

 ments the gases employed were moist, and no particular care had 

 been taken to remove the last traces of admixed air. Now Bunsen 

 and Roscoe, in their celebrated work on denotating mixtures of 

 hydrogen and chlorine, showed that regular results were only ob- 

 tained when the film of air condensed upon the surfaces of the 

 glass vessels employed was removed by allowing the gas to stream 

 through the apparatus for several days previous to the experiment. 

 A fresh series of experiments were therefore made, in which these 

 precautions were most rigidly observed; most complicated pieces 

 of apparatus were constructed of glass throughout, which admitted 

 of the drying of the gases prepared (in case of hydrogen and oxygen) 

 by the electrolysis of hot water, so as to exclude ozone and hydro- 

 gen peroxide; and the pure gases thus obtained were allowed to 

 stream through the series of bulbs united by capillary tubes for a 

 fortnight, night and day, before the bulbs were sealed off at the 

 capillaries. It was found that, with pure dry gases, scarcely a 

 trace of combination occurred by the fusion of the very fine capil- 

 laries. As regards the temperature of ignition of electrolytic 

 hydrogen and oxygen, or denotating carbon monoxide and oxygen, 

 it was found that bulbs containing them do not explode when 

 placed in boiling pentasulphide of phosphorus (518°), but do ex- 

 plode in vapor of stannous chloride (606°). The temperature of 

 ignition lies, therefore, between 518° and 606° C. The mode of 

 explosion differs considerably under different circumstances. In 

 case of explosion in vapor of stannous chloride, the bulb was never 

 shattered, but a sudden appearance of fiame within the bulb oc- 

 curred, accompanied by a slight detonation, and in some cases the 



point of the capillary was blown off. It is also astonishing how 

 long one requires to hold such a bulb in a Bunsen flame before 

 explosion occurs; it never occurs until the flame becomes colored 

 yellow, and the glass begins to soften, and frequently only causes 

 a swelling out of the glass at the heated spot. Thin-waUed bulbs, 

 however, are sometimes shattered. In two cases it was noticed 

 that the glass at the softened part was violently forced in, owing 

 to the previous heating having caused a large percentage of com- 

 bination, and hence the production of a partial vacuum. Even 

 after taking the rigid precautions to insure purity above described, 

 no definite quantitative rule connecting the time and percentage of 

 combination has been discovered, experiments performed simul- 

 taneously upon similarly treated mixtures yielding widely different 

 results; showing that the irregularities of glass surfaces, even after 

 removal of their air-films, are quite sufiicient to modify very sensi- 

 bly the conditions under which combination occurs. 



— The settlement founded by Mrs. Humphry Ward, on the 

 principles laid down in " Robert Elsmere," and which has its home 

 in University Hall, Gordon Square, London, has shown itself in- 

 tellectually active during the last year, according to the London 

 Journal of Education. The warden, the Rev. Philip Wicksteed, 

 M.A., has completed his arrangements for the winter lectures. He 

 will himself undertake a course of lectures on Dante. Mr. Wick- 

 steed has been tor some years a university extension lecturer, and 

 is one of the foremost English exponents of Dante. The more 

 immediate ends of the "Robert Elsmere'' position will be illus- 

 trated by the warden's course on the criticism of the Old Testa- 

 ment. Professor Knight of St. Andrew's, whose Wordsworth 

 studies have earned him a permanent place amongst literary men, 

 will give a series of lectures on " Some Aspects of Theism," a 

 course which will be treated both historically and philosophically. 

 Mr. R. G. Jloulton, a university extension lecturer of high reputa- 

 tion, will treat of "The Literary Study of the Bible." The ener- 

 getic warden will, further, lecture on the " Elements of Political 

 Economy." One of the great difficulties for the ordinary man in 

 the study of economics is the development of the mathematical 

 exposition of the subject. Thus Professor Jevon's •■ Theory"' is 

 founded on mathematics; so, too, the notes and appendices of Pro- 

 fessor Marshall's "Economics" are mathematical in treatment. 

 To meet the needs of those whose mathematics are shaky, a class 

 will be held after lectures, so as to enable all to follow, as closely 

 as possible, modern theoretical economics 



— In a lecture on "Old-time Winters in Essex County," deliv- 

 ered before the Essex (Ma^s.) Institute in May last, Mr. Perley 

 gave interesting particulars on many subjects, including weather, 

 some of which appear in the bulletin of the institute. The lecturer 

 spoke of the watch, church services, dress, food, and schools of the 

 early winter seasons; how the people spent their evenings, the 

 winter employment of the people in cutting off the forests, sled- 

 ding timber and wood, making pipe staves and barrel hoops, and, 

 most interesting of all, the institution of the old-fashioned shoe- 

 makers' shops, of which nearly every farm had one a century ago. 

 Women in those days engaged in spinning and weaving. The 

 holidays were referred to, Thanksgiving, Christmas, and New 

 Year's; and the winter's pleasures, such as sleigh-rides, dancing, 

 spinning and quilting parties, and games, shuffle-board, coasting, 

 skating, trapping, gunning, fishing, singing-schools, and girls' 

 samplers. He also spoke of the old modes of travel, snow-shoes, 

 etc. Nearly all the heavy teaming was done on sleds, and he 

 mentioned the winter of 1768-69, when the travelling was so bad 

 that the farmers in the western part of the State could not get 

 their grain and provisions to the coast to market. Snow remained 

 on the roads as it fell until about a century ago. Mr. Perley then 

 spoke of particular winters: that of 1641— i2. when the Indians 

 said they had not seen the ocean so much frozen for forty years ; 

 of 1646-47, when there was no snow to lay; of 1696-97, said to be 

 the coldest winter since the first settlement of New England ; of 

 1701-J, which was "turned into summer;" of 1717-18, when the 

 snow was from ten to fifteen feet deep and the drifts twenty-five 

 feet, many one-story houses being buried; of 1740-41, said to be 

 the severest winter known by the settlers, Salem harbor being 

 frozen over as early as October ; of 1774-75, a wonderfully mild 



