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NATURE 



[May 31, 1900 



to do the whole of the construction work in the few midnight 

 hours when the trains were not running. The system may be 

 termed a four-rail system. It includes the two ordinary track 

 rails, which are not used for any electrical purpose whatever, 

 and two electrical rail conductors placed on either side outside 

 the track. A special type of train has been designed for the 

 line, the design being such as to adapt it specially to the ex- 

 perimental conditions. There is no separate locomotive, the 

 train being worked in block, and a motor carriage being placed 

 at either end. Only one motor carriage, however, is used at a 

 time — viz. that, one in the front in the direction in which the 

 train is moving. This arrangement, while duplicating the 

 amount of electric motor plant, is convenient, as it obviates 

 shunting the motor carriage. It is intended to carry out. a 

 series of careful experiments on electric traction upon this 

 line, and for this purpose a dynamometer car will some- 

 times be attached to the train. Already certain experiments 

 have been made. In his evidence before the Select Committee 

 of the House of Commons considering the Manchester- Liverpool 

 Express Railway, Sir William Preece recently stated that the 

 train, fully loaded, had started on the very difificult gradient of 

 I in 43— a feat which an ordinary steam locomotive was unable 

 to perform when hauling a similar load. Moreover, in a tug- 

 of-war between the electric train and a steam locomotive, the 

 electric train readily overcame the steam engine. 



It has been said that every person is mentally a little un- 

 balanced, and that education from this point of view is simply 

 the attempt to secure and maintain mental equilibrium, which, 

 however, is never actually attained. Lapses of thought, inad- 

 vertencies in expression, and other slips in speaking or writing 

 (lapsus linguae and lapsus calimi) are thus of interest to the 

 psychologist as useful guides to the understanding of mental 

 processes. Every one has experienced unaccountable lapses of 

 this kind, and the lapse often comes as a surprise to the speaker 

 or writer himself. During a lecture, a professor inadvertently 

 referred to the "tropic of Cancercorn," intending to say "the 

 tropics of Capricorn and of Cancer." Many similar instances 

 might be cited, for example, the man who was going for a walk 

 to "get a breash of freth air," the person who inquired for the 

 " portar and mestle," and another who said " the pastor cut 

 the shermon sort." A physicist is recorded to have said that 

 he feared he should "get the instrument out of needle," when 

 he intended to say he feared he would "get the instrument out 

 of level and deflect the needle." This is curious, but it is not 

 so amusing as the order of " beggs and aeon" for breakfast, 

 or the remark of a nervous churchman to a stranger in his 

 seat, "Excuse me, but you are occupuing my pie." Mr. 

 H. Heath Bawden has made a detailed study of similar mental 

 lapses, both oral and graphic, and his results are described 

 in a monograph of the Psychological Review. It is suggested 

 that the aberrations dealt with are due to incipient aphasia 

 or agraphia, and the similarity between them is held to show 

 that our ordinary experience borders at every point on what 

 is called the abnormal or pathological condition. 



For some time past peat has been largely used in this 

 country as litter for stables in the place of straw. This material 

 is now likely to have a much more extended use, and the peat 

 bogs of this and other countries made to assume a value never 

 before realised. For the past twelve years Herr Zschorner, of 

 Vienna, has been investigating the properties of peat, and has 

 shown its possibilities. In the Vienna Exhibition of last year 

 was a building in which everything, from the carpets on the 

 floor to the curtains on the windows, and the paper on the 

 walls, had all been made from peat. Herr Zschorner's investi- 

 gations have shown that, although the fibres of the remains of 

 the reeds and grasses of which peat is composed have become 

 NO. 1596, VOL. 62] 



altered in their physical and chemical character, yet they have 

 not .suffered any anatomical change ; and while nothing capable 

 of fermentation or decay is left, the fibrous structure remains 

 intact ; that they are very durable, elastic, good non-conductors 

 of heat and non-combustible. Fabrics woven from them are 

 found to have the toughness of linen with the warmth of wool. 

 There is no textile fabric that cannot be woven from these 

 fibres. Blankets and other coverings used for horses and cattle 

 have been found in use to excel in warmth and cleanliness. 

 The unspun fibre is found to be a good substitute for absorbent 

 cottons possessing strong antiseptic properties. Paper of 

 several qualities has been made, and the uses to which peat 

 fibre has already been applied indicate possibilities that may 

 render the peat bogs of Ireland a valuable addition to the 

 resources of that country, and give full occupation to the 

 inhabitants of the " congested " districts. 



The Rendiconto of the Naples Academy for March and April 

 contains a complete list of the mathematical works of the late 

 Prof. Beltrami. 



In the Bulletin de la Classe des Sciences of the Belgian 

 Academy, M. Vandenberghe continues his researches on the 

 dissociation of substances in solution. The author, by new 

 experiments conducted with the use of solvents belonging to the 

 same homologous series, establishes the conclusion that the 

 influence exerted on the decomposition of molecular associations 

 by the solvent does not materially influence the effects due to 

 elevation of temperature. 



A PRELIMINARY note on the magnetic observations made 

 during the Belgica Antarctic expedition is given by M. G. 

 Lecointe in the Btilletin de la Classe des Sciences (Brussels). 

 For the measurements of declination Neumayer's apparatus was 

 used, the declination being the difference between the magnetic 

 azimuth of a star and the true azimuth calculated from the local 

 time. The Neumayer apparatus was also found far more suit- 

 able than the theodolite for measuring the horizontal com- 

 ponent, the instability of the theodolite as its feet began to sink 

 into the ice rendering observations made with it of little value. 

 In determining the inclination the great sensitiveness of 

 Gambey's compass could not be utilised regularly on account of 

 the ice-movements, and here again Neumayer's apparatus proved 

 the most serviceable. The paper consists chiefly of a table of 

 the recorded observations. 



In his Wilde Lecture, published in the Manchester Memoirs, 

 1899, No. 5, Lord Rayleigh discusses the mechanical principles 

 and possibilities of flight, both natural and artificial.- The 

 problem of the sailing bird is treated from the three alter- 

 native points of view, which attribute its source of energy to 

 upward currents, variation of wind-velocity with the altitude 

 and pulsating gu-.ts of wind. Lord Rayleigh then considers the 

 law of dependance of the aerial resistance of a plane surface on 

 its obliquity, and describ2s experimental methods whereby>^the 

 resistances at different obliquities may be compared by an 

 " astatic " arrangement, in which pairs of vanes are so adjusted 

 that the moments of the oppositely turned vanes balance each 

 other. In connection with the expenditure of power required 

 to support a given weight. Lord Rayleigh has calculated that, 

 in order for a man to support himself by a vertical screw by 

 working at the pjwer an average man can maintain for eight 

 hours a day, he would require a screw ninety metres in diameter, 

 and in this estimate no account has been taken of the weight 

 of the mechanism or of frictional losses. In conclusion, the 

 effects of flapping wings are briefly discussed. 



A FURTHER addition to Mr. H. C. Russell's interesting 

 current papers (No. 4), containing the tracks of 1 24 bottles 

 received during a year ending with September last, has been 



