234 



NATURE 



[December 14. 



ii>i 1 



animaU die as the result of this if kept long vxpospd to 

 the ozone. Concentrations which can just br senix-d by 

 smell, i.e. far lens than one part per million, have no 

 injurious effect, and can be used safely in systems of 

 ventilation. Injurious concentrations of ozone, by pro- 

 ducing irritation of the air-passages, cough, and headache, 

 compel anyone exposrd to such to remove himself from 

 the influence of ozone Ix-fore any serious damage is done 

 to the respiratory tract. Very low concentrations of ozone 

 mask disagreeable smells, give a fresh quality to air 

 vitiated by such smells, and vary the depressing monotony 

 of air which is artificiully warmed. Ozone may possibly 

 liav. some use in the treatment of disease of the respira- 

 loiv tract if used in concentrations which produce a slight 

 irritation, and thus bring more Glood and tissue lymph to 

 the part. — H. R. D«an : The factors concerned in 

 agglutination. (i) If, to a mixture of sheep corpuscles 

 with antiserum so dilute that no agglutination is visible be 

 added a solution of globulin obtained from normal guinea- 

 pig serum, the corpuscles are markedly agglutinated. By 

 use of suitable controls it can be demonstrated that neither 

 the globulin solution nor the dilution of antiserum employed 

 are of themselves capable of agglutinating the corpuscles. 

 (2) The substance present in the globulin solution which 

 aid-; j'gg utination is relatively thermostable, and its 

 presence can be demonstrated in whole heated guinea-pig 

 serum. (3) Corpuscles, sensitised and washed to remove 

 free antibody, can be agglutinated by the globulin solution. 

 If, after agglutination has taken place, the corpuscles be 

 removed with a centrifuge, the supernatant fluid can be 

 shown to have lost its agglutinating property. (4) The 

 agglutinating power of an extremely dilute antityphoid 

 serum can be increased by addition of globulin solution. 

 Adding this to a mixture of emulsion of W. typhosus with 

 a dilution of antiserum too weak by itself to agglutinate 

 bacilli, distinct agglutination can be obtained. (5) Forma- 

 tion of a specific precipitate by interaction of serum and 

 homologous antiserum depends on the presence in the mix- 

 ture <^f a relatively large amount of antiserum. If to a mix- 

 ture of serum with antiserum so diluted that it is no longer 

 able to produce a precipitate is added the globulin solution. 

 a definite turbidity is produced. (6) Probably agglutinating 

 serum (antiserum) contains two factors, both of which are 

 necessary to produce agglutination ; one of these is the 

 specific antibody, the other is a non-specific substance, 

 possibly serum globulin. The interaction of antigen with 

 antibody produces an aggregation of molecules of non- 

 specific substance, which may ultimately result in forma- 

 tion of definite turbidity. This process of aggregation of 

 the particles of non-specific substance is an essential part 

 of the process of agglutination. It is possible to make a 

 dilution of an antiserum which contains sufficient of specific 

 anti-substance, but not sufficient of non-specific substance. 

 Deficiency in non-specific substance can be made up by 

 addition of globulin solution obtained from normal serum. 

 — Arthur Harden and S. G. Paine : Action of dissolved 

 substances upon the autofermentation of yeast. All dis- 

 solved substances which plasmolyse the yeast-cell also 

 cause a large increase in the rate of autofermentation. 

 Substances such as urea, which even in concentrated solu- 

 tion do not produce plasmolysis, have no accelerating effect. 

 Toluene produces a similar effect to concentrated salt solu- 

 tions. The effect produced by salts is probably a direct 

 result of the concentration of the cell contents due to 

 plasmolysis, but in the case of toluene it is possible that 

 some other factor (such as disorganisation of the cell, or 

 hormone action) is concerned. — Prof. G. Dreyer and 

 W. Ray : Further experiments upon the blood volume of 

 manim.ils and it' relation to the surface area of the body. 

 — G. W. KIlis and J. A. Gardner: The origin and destiny 

 of cholesterol in the animal organism. Part viii. — On the 

 cholesterol content of the liver of rabbits under various 

 diets and during inanition. The authors have made 

 analyses of the livers of a number of rabbits fed on the 

 following diets : — cabbage, bran which had been extracted 

 with ether, extracted bran to which cholesterol had been 

 added. In some cases the cholesterol," instead of being 

 given with the food, was injected in olive-oil solution into 

 the peritoneal cavity. For animals fed on extracted bran 

 alone the total liver cholesterol per kilog. of body weight 

 is very constant, but when cholesterol is given with the 



2198, VOL. 88] 



food or injected into the peritoneal cavity a .«'"v;,t,.r-.' 

 incrra»e takes place. .\ similar increase was 

 the liver cholesterol during inanition, when the 

 on its own tissues. The percentage cholesterol cunitiu 

 the livers of newly-born animals is of the same order 

 that of normally fed adults. The results afford support 

 the working hypothesis, with regard to the origm .1 

 destiny of cholesterol in the organism, put forward fcoi 

 timi- ago by the authors, viz. that cholesterol is a ci 

 stituent constantly present in all cells, and when the**- c< 

 are broken down in the life process the cholesterol is i 

 excreted as a waste product, but is utilised in the forr 

 tion of new cells. A function of the liver is l«i 

 down dead cells, e.g. blood corpuscles, and elimin.-i' 

 cholesterol in the bile. .After the bile has been pout 

 the intestine in the processes of digestion, the ch' 

 is reabsorbed, possibly in the form of esters, and 

 in the blood stream to the various centres and tis.^ 

 reincorporation into the constitution of new cells. 



Physical Society, November 24. — Dr. A. Rueeell : 'I 



maximum value of the electric stress between two uneq 

 spherical electrodes. The experiments carried out 

 F. W. Peek (Journal Am. Inst, of Electrical Engine* : 

 191 1) for the General Electric Company of America prt 

 conclusively the value in practical work of a knowU-ii. 

 of how to compute the maximum value of the electrir • 

 between high-pressure conductors. With equal ^i 

 electrodes the electric stress between them can ea- . 

 computed from known tables. When, however, they . 

 unequal the calculation becomes so laborious that it is p; 

 hibitive to nearly every experimenter. The autl 

 develops formulae for this case, by means of which, and 

 the formula; for the capacity coefficients given in .1 

 paper to the society, the calculation is very app 

 shortened. When the distance between the spheres .- ■ 

 small compared with the diameter of either, the follow 

 approximate formula for R,^,. (the maximum value of ti 

 electric stress) can be used 



K„«,. = ( V/JT): I +(2* - «}r/(3aA) + {4(a - ^)' + a*}jr*/45^**)]. 

 where V is the maximum P.D. between the electrodes, 

 X their distance apart, a the radius of the smaller and b 

 the radius of the larger sphere. In this case a knowleii, 

 of the values of the capacity coefficients is not require*! 

 F. J. HarlOMT : The cubical expansion of fused silica. 1 

 author describes experiments in which measurements of i 

 cubical coefficient of expansion of fused silica from o* ' 

 to 100° C, and from 0° C. to 184° C, were made by t 

 weight thermometer method. The values obtained w- 

 ,S,,, = 99.8x 10-' and „S,,,= 144-7 x lo-*. The fun<i..- 

 mental coefficient is considerably less than that calculai-i 

 from previous linear measurements, whereas ,S,,, is or 

 slightly less. A low value of the fundamental coeffici' 

 is to be expected, since the coefficient has been shown 

 change sign at about —80° C. Observations of the : 

 point before and after heating showed that no perman- 

 charge in the volume of the bulb occurred through h< 

 ing, thus confirming the utility of fused silica for ther:- 

 metric purposes. — B. W. Clack : The temperature 

 efficient of diffusion. The paper describes further exp' 

 meats carried out by the author with an improved f<v 

 of the apparatus previously described (Proc. Ph. Soc., xv 

 p. 374), by means of which the value of the coefficient 

 diffusion of salts through water can be found at vari' 

 temperatures. Special flasks, similar to those aire., 

 employed, were filled with the solution under investigati. 

 and one was suspended from each arm of the balance i: 

 large bath of distilled water maintained at i 

 temperatures in a thermostat room. The diffusion : 

 both flasks were of equal length, but their cross- 

 differed considerably, and a method of differential xv 

 was used to compensate for any small changes in t- 

 ture. From the rate at which the flasks change in wci^ 

 the value of the coefficient of diffusion of the salt* 

 deduced. Figures are given for this value in the t.i~' 

 KCl and KNO, at various concentrations and at d •: ' 

 temperatures, and from these figures the tempt lai. 

 coefficient of diffusion is found. — E. Marsden and 

 Barratt : The a particles emitted by the active deposit- 

 thorium and actinium. In a previous paper (Proc. Pli 

 Soc, August) the authors showed that if a particles . 



NO. 



