I90 



NATURE 



[June 25, 1903 



A number of observations have been made on normal 

 subjects leading a quiescent life, with comparative rest of 

 the muscles ; and on persons subjected to varying degrees 

 of exercise, and to different temperatures and altitudes. In 

 this note the author limits himself, however, to a statement 

 of results obtained in the former class of subjects only. 



The numerous observations which this inquiry necessitated 

 on the corpuscles, and on the haemoglobin, were made by the 

 haemocytometer tubes and the haemoglobinometer, which 

 were described by the author before the Physiological Society 

 some few years ago (see Journal of Physiology, Cambridge 

 and London, vol. xix. p. 15), and the specific gravity of the 

 blood was determined by Roy's method. The blood- 

 pressures (arterial, capillary, and venous) were read by the 

 hajmodynamometer {ibid., vols, xxii., xxiii.), and Hill and 

 Barnard's sphygmometer, and Prof. Gartner's tonometer, 

 were also occasionally used in determining the arterial 

 pressure. 



Some of tTie general conclusions afforded by the observ- 

 ations may be thus epitomised : — 



(i) The amount of tissue fluid varies at different times 

 in the course of the day, and each variation is of short 

 duration. 



(2) The ingestion of food produces a rapid flow of lymph 

 into the tissue spaces, which in an hour after the meals 

 acquires its maximum development, and then it slowly sub- 

 sides, and only ceases to be apparent after the lapse of from 

 3 to 4 hours. 



(3) The digestive curve of variation always follows the 

 same general type ; the rise being rapid, the acme short, 

 and the subsidence gradual. The variations were observed 

 to follow this well-defined order in all the healthy subjects 

 so far submitted to observation. The curve of variation is, 

 therefore, rhythmical — the wave abruptly rising to an acme 

 and then somewhat slowly subsiding. 



The following are two examples : — 

 Example i. 



Corpuscles per cent. 

 Before the meal 99^ (4,950,000 per c.mm. )) 



Dift. 



Per- 



centage 



of 

 lymph. 



(breakfast) 



1 hour after ... 



2 hours after . . 



3 hours after . . , 



4 hours after ... 



103 



91 



106 



94 

 105 



96 

 104 



98 

 loi 



(5,150,000 

 (4,550,000 

 (5,300,000 

 (4,700,000 

 (5,250,000 

 (4,800,000 

 (5,200,000 

 (4,900,000 

 (5,050,000 

 Example 2. 



750,000 15 



550,000 II 



400,000 8 



150,000 3 



Corpuscles per cent. 



Diff. 



Before the meal 99 (4,950,000 per c.mm.)) 



Per- 

 centage 



of 

 lymph. 



(dinner) 

 I hour alter 



2 hours after 



3 hours after 



i} 



None 

 850,000 

 600,000 



None 



17 



99 (4,950.000 „ )/ 



91 (4,550,000 ,, )\ 



108 (5,400,000 ,, )j 



94 (4,700,000 „ )\ 



106 (5,300,000 ,, )J 



104 (5,200,000 

 104 (5,200,000 



(4) The amount of lymph is proportionate to the rise of 

 the mean arterial and capillary pressures, and these pres- 

 sures have been found to follow exactly the same prolonged 

 rhythmical course after the ingestion of food as does the 

 effusion of lymph. 



The following example shows the agreement between the 

 blood-pressures and the amount of lymph : — 



Before the meal ... . 

 I hour after 



1 hour after 



\\ hours after 



2 hours after ... . 



3 hours after ... . 



1 The figure on the first line represents the percentage of corpuscles 

 before, and the figure on the second line that after, compression of the 

 finger by the rubber ring. 



NO. 1756, VOL. 68] 



The method devised for observing the capillary pressure 

 is not quite so delicate for the smaller variations as could 

 be wished, and the author hopes to improve it ; but it is- 

 sufliciently definite to show that the capillary blood-pressure 

 is raised throughout the digestive circulatory disturbance^ 

 and especially so at the acme of it, and falls again at the 

 close of it. When the mean arterial pressure is 100 c.mm» 

 Hg before a meal, as in the above example, the capillary 

 blood-pressure will read 20 c.mm. Hg ; and in an hour after 

 the meal, when the arterial pressure rises to 115 c.mm. Hg, 

 or so, the capillary pressure will rise to at least 30 c.mm. 

 Hg. Though this is a large relative rise,, the author's- 

 observations show that it is not less than this, and that it 

 is often more. 



Physical Society, June 12.— Dr. R. T. Glazebrook^ 

 F.R.S., president, in the chair. — Some experiments on 

 shadows in an astigmatic beam of light, by Prof. S. P. 

 Thompson. Two years ago Prof. Thompson showed 

 before the Society some experiments on the shadows formed 

 when a thin rod is placed in a beam of light which has 

 passed through a tilted plano-convex lens. In those ex- 

 periments the peculiar effects were chiefly due to the 

 aberration known as coma. Following up his experiments,. 

 Prof. Thompson has investigated the shadows produced 

 when a thin rod is placed in an astigmatic beam. — On a 

 method of determining the viscosity of pitch-like solids, by 

 Prof. F. T. Trouton and Mr. E. S. Andrews. The 

 various methods which have been proposed for measuring 

 viscosity meet with difficulties when it is attempted to 

 apply them for the measurement of the viscosity of bodies- 

 such as pitch. To obviate some of these difficulties a 

 method has been devised in which a constant torque is- 

 applied to a cylinder of the substance, and the relative rate 

 of rotation of the ends is observed. From these and the 

 dimensions of the cylinder, the viscosity can be calculated 

 by means of a formula deduced in the paper. — The positive 

 ionisation produced by hot platinum in air at low pressures, 

 by Mr. O. W. Richardson. The experiments described irr 

 this paper were almost all made at temperatures so low- 

 that there was no appreciable negative ionisation. In ex- 

 amining the relation between the current from a positively 

 charged hot platinum wire and the applied E.M.F. at low 

 pressures, results were obtained which indicated that the 

 value of the current fell off with time when the other con- 

 ditions were kept constant. Further experiments showed 

 that the current died away rapidly at first until it reached 

 a steady value which only disappeared gradually. 



Royal Astronomical Society, June 12. — Prof. H. H. 

 Turner, F.R.S., president, in the chair. — The president 

 announced the death of Dr. A. A. Common, and a vote of 

 condolence with his relatives was put from the chair and 

 passed by the meeting. — A letter (accompanying a paper on 

 the present condition of the lunar theory) from Mr. Nevill, 

 director of the Natal Observatory, was read, in which the 

 writer stated that the reductions desired by Prof. Newcomb 

 had already been made, and were awaiting publication at 

 th? Natal Observatory. — The secretary read a paper, by 

 Prof. E. W. Brown, on the verification of the Newtoniar* 

 law, which gave rise to a discussion in which Prof. New- 

 comb and others took part. — Mr. Newall exhibited and 

 explained a series of slides from spectroheliographs of solar 

 faculae, &c., taken by a new method by Prof. G. E. Hale 

 at the Yerkes Observatory, and Dr. Lockver showed slides- 

 taken at South Kensington. — Mr. E. W. Maunder read a 

 paper by himself and Mr. J. E. Evans on experiments as- 

 to the actuality of the " canals " observed on Mars. A 

 drawing of the planet, showing no canals, had been placed 

 before classes of boys at the Greenwich Hospital School, 

 who were set to copy it. It was found that those closest 

 to the original, and therefore able to see the actual detail, 

 drew no canals, but those placed at a further distance made 

 copies in which they delineated canals, in many cases almost 

 exactly as they are represented in drawings by Schiaparelli 

 and others. The author's conclusion was that the so-called 

 " canals " were mainly the interpretation by the observer of 

 faint markings just at the limit of visibility. It also 

 appeared that observers were inclined to prolong into lines 

 any projecting points on the edges of the Martian " seas,"" 

 and also to draw hard lines at the boundaries of faint shades. 

 Mr. Maunder was convinced that the boys employed in the 



