802 



SCIENCE 



[N. S. Vol. XL. No. 1040 



through the rise of temperature, the intensities 

 of all orders diminish, but those of higher 

 order much more than those of lower. The 

 effect was foreseen by the Dutch physicist 

 Debije, and the amount of it was actually 

 calculated by him on certain assumptions. I 

 haye found experimental results in general 

 accord with his formula. In passing it may 

 be mentioned that as the crystal expands with 

 rise of temperature the spacing between the 

 planes increases and the angles of reflection 

 diminish, an effect readily observed in practise. 



This part of the work gives information 

 respecting the movements of the atoms from 

 their places, the preceding respecting their 

 average positions. It is sure, like the other, 

 to be of much assistance in the enquiry as to 

 atomic and molecular forces, and as to the 

 degree to which thermal energy is locked up in 

 ,the atomic motions. 



This brief sketch of the progress of the new 

 science in certain directions is all that is pos- 

 sible in the short time of a single lecture: but 

 at may serve to give some idea of its fascina- 

 tion and possibilities. 



William H. Bragg 



WALTEB EOLBBOOK GASKELL {mi-WU) 

 Dr. Walter Holbrook Gaskell, university 

 lecturer on physiology and prelector on nat- 

 ural science at the University of Cambridge 

 since 1883, died suddenly, after a short illness, 

 on September 7, 1914. He came of a well- 

 known Unitarian family in the north of Eng- 

 land, and was born at Naples, on November 1, 

 184Y. After receiving his preliminary educa- 

 tion, he entered Trinity College, Cambridge, 

 in 1865, subsequently taking a medical degree 

 at University College, London, in 1878. At 

 Cambridge, Gaskell was one of the earliest to 

 come under the influence of Michael Poster, 

 then prffilector on physiology, and, at his 

 instance, entered Ludwig's laboratory at 

 Leipzig in 1874. Prior to Poster's advent, 

 Gaskell had specialized in mathematics, being 

 one of the wranglers in the Mathematical 

 Tripos in 1869. Prom the date of his first 

 paper, an important research on the vaso-di- 



lator fibers of striated muscle,^ the rest of his 

 life was devoted to those researches on the 

 motor mechanism of the heart and the sympa- 

 thetic system which have made his name so 

 well known in physiology and clinical medi- 

 cine. 



English physiology in the first half of the 

 nineteenth century was represented mainly 

 by the work of Sir Charles Bell (spinal 

 nerve roots), Marshall Hall (reflex action), 

 William Sharpey (ciliary motion), Sir Wil- 

 liam Bowman (theory of urinary secretion), 

 William Prout (HCl in the gastric juice) and 

 Thomas Graham (osmosis, colloids). In 

 1867 Michael Poster was Sharpey's assistant 

 at University College, and, in 1870, at Hux- 

 ley's instance, became praslector at Cambridge, 

 while Burdon Sanderson became Waynefleet 

 professor of physiology at Oxford in 1882. 

 Prom the teaching and inspiration of these 

 two men came most of the brilliant names 

 which have distinguished English physiology 

 in the later period, with the exception of 

 Starling, whose name is associated with Guy's 

 Hospital. Schaefer was a Sharpey pupil, and 

 was persuaded by Foster to devote his life to 

 research. Leonard Hill and Gotch were Ox- 

 ford men. Prom Cambridge came Langley, 

 Henry Head, Sherrington, Eoy, Adami, Gow- 

 land Hopkins and Gaskell. 



When Gaskell began to work with Ludwig, 

 every one believed in the so-called neurogenic 

 theory of the heart's action, introduced by 

 Borelli in 1680, viz., that the heart's move- 

 ments, beat and tonus are due to nervous im- 

 pulses. A little before Borelli, Harvey, in his 

 demonstration of the circulation of the blood 

 (1628), had advanced the idea that the heart 

 is a muscular force pump, propelled by its 

 own internal heat. This mystic dogma (the 

 myogenic theory) was stated in more modern 

 form by Haller in 1757, viz., that the heart's 

 contraction is due to an inherent " irritability " 

 of its muscle, the stimulus being the entrance 

 and passage of venous blood through it. Both 

 theories, neurogenic and myogenic, have had 

 their ups and their downs to date. The neu- 

 rogenic theory was restated by Legallois in 



iProc. Boy. Soc. Lond., 1877, XXV., 439^45. 



