574 



NATURE 



[October 3, 1907 



dialing probably is to bind the molecules into a rigid 

 mass quite irrespective of any special polar attractions 

 \\ liich the_\- may have for each other. They are bound 

 ((iy:ether by the general cohesive force, and their free- 

 dom of movement is much curtailed. This is evident 

 not only because they cannot move sullicifntly freely 

 to take up the regularly oriented arrangement, but 



Fig. I. — Hard-drawn gold wire. Magnification X700. 



also because their elasticity in this state is much less 

 perfect than it is in the crystallised state ; the mole- 

 cules cannot vibrate freely in the amorphous state. 



The effect of raising the temperature to the crys- 

 tallising point is to raise the kinetic energy of the 

 molecules, and therefore to neutralise a part of the 

 cohesive force, thus weakening it and enabling the 



Fig. 2.— Hard-drawn gold wire after crystallisation at 280°. Magnificatit 



i.oUcules to spring into their uniformly oriented posi- 

 ion ; the crystalline state is thus restored and the 

 inti-rnal energy of the mass is reduced. The present 

 observations -show that crystallisation occurs over a 

 short and definite range of temperature — short, that is 

 to say, compared with the ranges above and below 

 the crystallisation range. Below the crystallisation 

 NO. 1979, VOL. 76] 



range the amorphous or non-crystalline form of the 

 metal is known by direct observations to be perfectly 

 stable down to -iSo°, while above that range the 

 crystalline form is stable up to the temperature of 

 liquefaction. 



The changes in the electrical, mechanical, and other 

 properties, which occur when the crystallisation range 

 is reached, amply confirm the microscopic observations, 

 and all point to the occurrence of an important change 

 in the molecular structure. 



By means of an acoustical method it has been found 

 possible to detect the minute changes in elasticity 

 which occur as the temperature is gradually raised to 

 the crystallising range. In this way it has been made 

 evident that there are two distinct stages in the relief 

 of the molecular strains which are caused by harden- 

 ing. In the first stage no important alteration in the 

 other properties of the hardened metal occurs, while 

 in the second and more important stage the complete 

 restoration of elasticity e.Kactly corresponds with the 

 other changes which occur at the crystallisation tem- 

 perature. 



OCTOBER METEORS. 



OCTOBER is a month when meteors are decidedly 

 numerous. They are particularly abundant 

 from October 15 to October 25, and this period in- 

 cludes the well-known shower of Orionids, but the 

 conditions will be unfavourable this year owing to 

 the full moon of October 21. 



Early in the month there is occasionally a rich 

 shower near the northern boundary of Bootes at 

 230° + 52°, and on October 8 there are many meteors 

 from Aries about 42° + 20°, from Auriga, 77°+32°. 

 and from about this date to October 20 there is a well 

 pronounced morning shower of long-pathed meteors 

 from 154° -I- 39°. 



Before sunrise the observer will also trace radiants 

 at ioi°4-i°, 100°+ 13°, io8°+i3°, i2i°-(-o°, 133° -1-68°, 



i3.3°+48°- 



Thirty years ago, viz. in 1877, during the first week 

 in .October there were very well [ironounced showers 

 at i33°+79° and 313°+ 77°; the former gave swift 

 streak-leaving meteors, the latter slow faint meteors. 



October furnishes several radiants of Perseids, and 

 one of the most notable of these agrees precisely in 

 its apparent position with the centre of the great 

 display of August Perseids on the date of maximum. 

 Between October 8 and 14 I have recorded a number of 

 slow meteors from a well defined radiant at 45°-(-58°. 



The principal shower in the last half of October is 

 one of Arietids from near f. On 1S77 October 28- 

 November i, I saw thirty-one meteors from 43°-|-22°, 

 and on 1887 October 11-24, forty-five meteors were 

 registered from 40°+ 20°. The members of this system 

 are white, rather slow, and occasionally brilliant, 

 with trains of yellow sparks. As they were very active 

 in 1877 and 18S7, they may periodically recur at 

 intervals of a decade, and be numerously manifested 

 again in 1907. W..F. Denning. 



MR. H.ALD.iNE ON SCIENCE IN, COMMERCE. 



A VERBATIM report of the speech on scientific 

 -'*■ commercial education in relation to the success- 

 ful pursuit of trade, delivered bv Mr. Haldane at 

 Liverpool on September 19, and brieflv mentioned in 

 last week's Natirk, appeared in the Liverpool Daily 

 Post of .September 20. The two main points developed 

 by Mr. Haldane in the course of his remarks were the 

 domination of mind over matter and the value of 



