356 



NATURE 



[November io, 192 i 



Calendar of Scientific Pioneers. 



November 10, 1832. Johann Caspar Spurzheim 

 died. — The disciple of and fellow-worker with Gall, 

 the founder of cerebral physiology, Spurzheim studied 

 medicine in Vienna, and with Gall published 

 "Anatomie et Physiologic du Syst^me nerveux en 

 g^nerale et du Cerveau en particulier." 



November 10, 1852. Gideon Algernon Mantell died. 



-—Especially successful in the discoverv and descrip- 

 tion of fossils of the South Downs, Mantell was a 

 surgeon by profession and practised at Lewes, 

 Brighton, and Clapham. His collections are pre- 

 served in the British Museum and his drawings in 

 Yale University. 



November 12, 1793. Jean Sylvain Bailly died.— 



Originally intended for a painter, an acquaintance 

 with Lacaille led Bailly into astronomical studies, and 

 in 1763 he became a member of the Paris Academy 

 of Sciences, establishing his reputation by a memoir 

 on Jupiter's satellites. Later on he published a his- 

 tory of astronomy. A promoter of the French Revo- 

 lution, the day of the storming of the Bastille, July 14, 

 1789, he was chosen mayor of Paris. His action at 

 the Champs de Mars, July 17, 1791, lost him his 

 popularity, and two years later he perished beneath 

 the guillotine. 



November 13, 1802. Andre Michaux died.— Acquir- 

 ing a taste for botany from his father, Michaux 

 studied under Jussieu, anti travelled in Spain, 

 Persia, and North America. He died at Madagascar 

 while on a journey to Australia. The genus 

 Michauxia is named after him. 



November 14, 1716. Gottfried Wilheim Leibniz died. 



— Born in Leipzig towards the end of the Thirtv 

 Years' War, Leibniz was the son of a professor of 

 moral philosophy. During diplomatic missions to 

 France and England he became acquainted with 

 Huygens, Boyle, and Newton, and it was through 

 Huygens he was led to study geometry. In 1676 he 

 became librarian to the Hanoverian family, a post he 

 held until his death. Equally eminent as a philo- 

 sopher and a mathematician, he is recognised as one 

 of the discoverers of the infinitesimal calculus, and 

 the inventor of the accepted notation. The inaugura- 

 tion of the Berlin Academy of Sciences was due to 

 him, and he became its first president. 



November 15, 1630. Johann Kepler died.— Immor- 

 talised by his discovery of the laws of planetary 

 motion, Kepler "may be said to have constructed the 

 edifice of the universe." Taught astronomy at 

 Tubingen by Maestlin, in 1593 he succeeded Stadt as 

 professor of that subject at Gratz, and in 1600 joined 

 Tycho Brahe at Prague, after Tycho's death becom- 

 ing Court mathematician to the Emperor Rudolph II. 

 From 1612 to 1629 he was at Linz, and the following 

 year he died at Ratisbon. Applying the diverse talents 

 of a singularly gifted mind to" the study of Tycho's 

 observations, Kepler in 1609 discovered the first two of 

 the laws which bear his name, and in 1618 the third. 

 His "Astronomia Nova" is among the classics of 

 science. At his death his manuscripts were purchased 

 by Hevelius, and are now preserved at Pulkowa 

 observatory. 



November 16, 1915. Raphael Meidola died.— For 



thirty years professor of chemistry at the Technical 

 College, Finsbury, Meidola was especially known for 

 his work on the chemistry of colouring rnatters. The 

 friend of Darwin, he was also a naturalist, translated 

 Weismann's "Theory of Descent," and was president 

 of the Entomological Society. E. C. S. 



NO. 2715, VOL. 108] 



Societies and Academies. 



London. 

 Royal Society, November 3. — Prof. C. S. Sherrington, 

 president, in the chair. — T. R. Merton : The spectra 

 of lead isotopes. Comparison of the wave-lengths 

 of five lines in the spectra of ordinary lead 

 and lead from Australian carnotite shows differences 

 which are not constant, but vary for the different 

 lines. The diflference in wave-length observed for the 

 principal line, A = 4058 A., is about two hundred times 

 as great as that expected on theoretical grounds.— 

 G. I. Taylor : Experiments with rotating fluids. 

 Methods are described by which experiments on 

 spheres, cylinders, and vortex rings moving through 

 rotating fluids can be projected in a lantern and in- 

 stantaneous photographs taken. If any small motion 

 be given to a rotating fluid, the resulting flow will be 

 such that concentrated masses of coloured liquid should 

 be drawn out into thin films, parallel to the axis of 

 rotation. Photographs taken by a camera placed ver- 

 tically above a rotating basin of water show that the 

 liquid moves in this way. — L. Bairstow, Miss B. M. 

 Cave, and Miss E. D. Lang : The two-dimensional 

 slow motion of viscous fluids. In its restricted form 

 the equation of motion of a viscous fluid isVV = o» 

 where -6 is Stokes's stream function. If the molecular 

 rotation in the fluid be defined by f =VV» the equation 

 of motion may be expressed alternatively as V'i = o- 

 The equation VV = o '^ transformed by means of 

 Green's theorem to a form in which the only unknown 

 is the distribution of the i doublets on the boundaries. 

 The strengths of the doublets are found by solving the 

 resulting integral equation. An example shows the 

 motion of fluid past a circular cylinder in an infinite 

 parallel-walled channel. If d be the diameter of the 

 cylinder, p the density of the fluid, v the kinematic 

 coefflcient of viscosity, and U the velocity of the fluid 

 in the centre of the channel at infinity, then, w-hen 

 the width of the channel is 5c?, the resistance per unit 

 length of cylinder is R = 7-iopi'dU. The value of 

 Ud/v to which this formula applies is not to exceed 

 0-2. — H. C. H. Carpenter and Constance Elam : The pro- 

 duction of single, crystals of aluminium and their ten- 

 sile properties. The parallel portion of the test pieces 

 of the sheet was 4 in. x i in.Xo-i25 in., consisting of 

 about 1,687,000. The conversion of this area into a 

 single crystal involved heat treatment for six hours 

 at 550° C., tensile stress of 2-4 tons per square inch, 

 producing an average elongation of i-6 per cent, on 

 3 in., and final heat treatment beginning at 450° and 

 extending up to 600° C. On an average, one test 

 piece in four produces a single crystal over its parallel 

 portion, which frequently grows up into the shoulders 

 of the test piece. The tenacity of single crystals varied 

 from 2-8 to 408^ tons per sq. in., while the extension 

 on 3 in. varied from -^4 to 86 per cent., according to 

 the orientation of crystal relative to stress. Five types 

 of specimens were recognised. Stress tests of test 

 pieces consisting of two and three crystals show the 

 strengthening influence of one crystal upon another. 

 Experiments on round bars resulted in the produc- 

 tion of single crystals in the parallel portion of bars 

 0-564 and 0798 in. in diameter. The total volumes of 

 the crystals were more than i cb.in., and more than 

 2 cb.in. respectively. The tensile properties were de- 

 termined, and in every case a wedge-shaped fracture 

 was produced, the bar diminishing principally in one 

 dimension only. Remarkable twinning effects were 

 observed in certain cases. — C. V. Raman and B. Ray : 

 The transmission colours of sulphur suspensions. 

 When a few drops of sulphuric acid are added to a 

 dilute solution of sodium thiosulphate and a precipi- 



