The diffusion of gases through liquids and allied experiments . the diver, the result would be nil in the lapse of time, supposingthere is no continuous mean rise or fall of temperature, the latter in itseffects being indistinguishable from diffusion. The issue in question,however, is the change of composition of the imprisoned air, which becomescither relatively rich or poor in oxygen; and this modifies the gradientscorrespondingly. Any change of barometric pressure, moreover, is felt inthe gas inside and outside of the diver at once, but it does not follow thatit is also felt in the pores of
RM2AJBNGNThe diffusion of gases through liquids and allied experiments . the diver, the result would be nil in the lapse of time, supposingthere is no continuous mean rise or fall of temperature, the latter in itseffects being indistinguishable from diffusion. The issue in question,however, is the change of composition of the imprisoned air, which becomescither relatively rich or poor in oxygen; and this modifies the gradientscorrespondingly. Any change of barometric pressure, moreover, is felt inthe gas inside and outside of the diver at once, but it does not follow thatit is also felt in the pores of
The diffusion of gases through liquids and allied experiments . WASHINGTON, D. C. Published by the Carnegie Institution of Washington 1913 CARNEGIE INSTITUTION OF WASHINGTON PUBUCATION No. 186 PRESS OF GIBSON BROTHERSWASHINGTON, D. C. PREFACE. Obsenang that the Cartesian diver used in my lectures since 1895 grewheavier from year to year, I resolved in 1900 to make definite measurementsof the rate of loss of buoyancy, believing that these would be fruitful; theywould bear directly on the coefficient of diffusion of the imprisoned gasthrough the liquid in which the diver is floating; it would be
RM2AJC22WThe diffusion of gases through liquids and allied experiments . WASHINGTON, D. C. Published by the Carnegie Institution of Washington 1913 CARNEGIE INSTITUTION OF WASHINGTON PUBUCATION No. 186 PRESS OF GIBSON BROTHERSWASHINGTON, D. C. PREFACE. Obsenang that the Cartesian diver used in my lectures since 1895 grewheavier from year to year, I resolved in 1900 to make definite measurementsof the rate of loss of buoyancy, believing that these would be fruitful; theywould bear directly on the coefficient of diffusion of the imprisoned gasthrough the liquid in which the diver is floating; it would be
The diffusion of gases through liquids and allied experiments . 00550 g/day = 64X lo^^g/sec.and it thus much exceeds the converse case of table 2; but this rapid influxis soon reduced in the lapse of time. The bubble phenomenon, due to the diffusion of hydrogen into micro-scopic air-bubbles adhering to solid parts, under water, was equally promi-nent. During the early days these gathered in great quantity and had tobe shaken off. It would be interesting to estimate the virtual pressure at LIQUIDS AND ALLIED EXPERIMENTS. 27 which the bubbles are initially expanded. In fact, if the pressure with
RM2AJBWPKThe diffusion of gases through liquids and allied experiments . 00550 g/day = 64X lo^^g/sec.and it thus much exceeds the converse case of table 2; but this rapid influxis soon reduced in the lapse of time. The bubble phenomenon, due to the diffusion of hydrogen into micro-scopic air-bubbles adhering to solid parts, under water, was equally promi-nent. During the early days these gathered in great quantity and had tobe shaken off. It would be interesting to estimate the virtual pressure at LIQUIDS AND ALLIED EXPERIMENTS. 27 which the bubbles are initially expanded. In fact, if the pressure with
The diffusion of gases through liquids and allied experiments . Furthermore, in this case the sharp screwss and similar sharp edges elsewhere as in the disks cc, dd, etc., are inadmis-sible. Without rounded edges and a rounded screw, the secondary dis-turbances due to electric winds interfere with the interpretation of themeasurements and the apparatus will not take a high potential. All partsexcept the disk cc are of course put to earth, and possible induction betweencc and other conductors except dd must be scrupulously guarded against. Finally, fig. 12 shows an alternative float consisting
RM2AJBTHGThe diffusion of gases through liquids and allied experiments . Furthermore, in this case the sharp screwss and similar sharp edges elsewhere as in the disks cc, dd, etc., are inadmis-sible. Without rounded edges and a rounded screw, the secondary dis-turbances due to electric winds interfere with the interpretation of themeasurements and the apparatus will not take a high potential. All partsexcept the disk cc are of course put to earth, and possible induction betweencc and other conductors except dd must be scrupulously guarded against. Finally, fig. 12 shows an alternative float consisting
The diffusion of gases through liquids and allied experiments . 44 THB DIFFUSION OF GASES THROUGH To compute/j, a suitable value of D and V must be assumed. Let Z) = 4cm. and Kin succession 10^, io^Xi.41, io^Xi.86, 10^X2 volts. Since /,= FV2.262Xio«(4-/) the successive curvilinear lines of the diagram are obtained. The lowesthave two intersections each; the one corresponding to stability being at 5and the unstable one at us. For at s, a lowering of the disk means anexcessive upward electric force, while any rise of the disk means an excessivedownward and mechanical force. Just the reverse is t
RM2AJBTCCThe diffusion of gases through liquids and allied experiments . 44 THB DIFFUSION OF GASES THROUGH To compute/j, a suitable value of D and V must be assumed. Let Z) = 4cm. and Kin succession 10^, io^Xi.41, io^Xi.86, 10^X2 volts. Since /,= FV2.262Xio«(4-/) the successive curvilinear lines of the diagram are obtained. The lowesthave two intersections each; the one corresponding to stability being at 5and the unstable one at us. For at s, a lowering of the disk means anexcessive upward electric force, while any rise of the disk means an excessivedownward and mechanical force. Just the reverse is t
The diffusion of gases through liquids and allied experiments . ditions under which flow takes place. In fig. I, ab is a. rubber hose filled with water,terminating in the receiver R. Here the lowerlevel of water may be read off. Moreover, R isprovided with an open hose C, through which pres-sure or suction may be applied by the mouth, forthe purpose of raising or lowering the swimmer, vd, in the column A. Inthis way constancy of temperature is secured throughout the column. 3. Barometer.—The apparatus is obviously useful for ordinary baro-metric purposes, and provided the temperature, /, of th
RM2AJBY41The diffusion of gases through liquids and allied experiments . ditions under which flow takes place. In fig. I, ab is a. rubber hose filled with water,terminating in the receiver R. Here the lowerlevel of water may be read off. Moreover, R isprovided with an open hose C, through which pres-sure or suction may be applied by the mouth, forthe purpose of raising or lowering the swimmer, vd, in the column A. Inthis way constancy of temperature is secured throughout the column. 3. Barometer.—The apparatus is obviously useful for ordinary baro-metric purposes, and provided the temperature, /, of th
The diffusion of gases through liquids and allied experiments . of measurement presently to be given will depend upon thispossibility. 39 40 THE DIFFUSION OF GASES THROUGH To keep the water level at the proper height or to raise or lower it by adefinite amount, the screw pump in fig. 13 is available. This consistsessentially of a thick screw S playing into the brass tube cc, which is closedat the top by the stuffing box a compressing the ring of soft material bb.The bottom of the tube cc ends in the tubulure i, to be joined by appro-priate tubing with the corresponding tubulure i in fig. 11 a.
RM2AJBTR0The diffusion of gases through liquids and allied experiments . of measurement presently to be given will depend upon thispossibility. 39 40 THE DIFFUSION OF GASES THROUGH To keep the water level at the proper height or to raise or lower it by adefinite amount, the screw pump in fig. 13 is available. This consistsessentially of a thick screw S playing into the brass tube cc, which is closedat the top by the stuffing box a compressing the ring of soft material bb.The bottom of the tube cc ends in the tubulure i, to be joined by appro-priate tubing with the corresponding tubulure i in fig. 11 a.
The diffusion of gases through liquids and allied experiments . variety, but the formshown in the annexed fig. 16 was finally preferred.Here vd is the Cartesian diver capable of rising inthe tube cmm, open below, closed above by thestoppered thermometer / and kept full of water.Thus the bulb of this thermometer seres additionally as a stop for the diver on flotation. Thediver must fit very loosely in the tube, so thatthere may be a minimum of viscous resistance toits vertical motion. There should be at least 0.5cm. clear space all around the diver. To preventit from sinking completely, a vert
RM2AJBRBJThe diffusion of gases through liquids and allied experiments . variety, but the formshown in the annexed fig. 16 was finally preferred.Here vd is the Cartesian diver capable of rising inthe tube cmm, open below, closed above by thestoppered thermometer / and kept full of water.Thus the bulb of this thermometer seres additionally as a stop for the diver on flotation. Thediver must fit very loosely in the tube, so thatthere may be a minimum of viscous resistance toits vertical motion. There should be at least 0.5cm. clear space all around the diver. To preventit from sinking completely, a vert
The diffusion of gases through liquids and allied experiments . of glass. H is thebarometric height diminished by the head equal tothe vapor pressure of water vapor, r the absolutetemperature, and R the gas constant of hydrogen.The latter applies at the outset only. Since M =18.09 grams p„=i3.6 g = 98i i? = 4i.4Xio^ the constant A = Mgp^/R = 0.005823. The hydro-gen used was obtained electrolytically from water,enough being introduced into the swimmer to justprevent flotation. In the course of time the gases contained in thediver will change from the influx of diffused air andthe efflux of hydr
RM2AJBXRHThe diffusion of gases through liquids and allied experiments . of glass. H is thebarometric height diminished by the head equal tothe vapor pressure of water vapor, r the absolutetemperature, and R the gas constant of hydrogen.The latter applies at the outset only. Since M =18.09 grams p„=i3.6 g = 98i i? = 4i.4Xio^ the constant A = Mgp^/R = 0.005823. The hydro-gen used was obtained electrolytically from water,enough being introduced into the swimmer to justprevent flotation. In the course of time the gases contained in thediver will change from the influx of diffused air andthe efflux of hydr
The diffusion of gases through liquids and allied experiments . uch heavier swimmer, so that a decrease of the area ofdiffusion due to loss of gas by transpiration may not occur. The curve, asbefore, is remarkably regular and partakes of the qualities of the earliercurve (fig. 5). The initial rate is — m = 71 X io^g/day or 8.2 X io^^g/sec.,which is of the same order as the datum of table 2, remembering that theconstants of the apparatus are slightly different. The coefficients of trans-piration are, since a =11.5 cm.^(inside area), //= 11.5 cm. 2/f = 9.ocm. / = 20.5 cm. and, if the water hea
RM2AJBW2TThe diffusion of gases through liquids and allied experiments . uch heavier swimmer, so that a decrease of the area ofdiffusion due to loss of gas by transpiration may not occur. The curve, asbefore, is remarkably regular and partakes of the qualities of the earliercurve (fig. 5). The initial rate is — m = 71 X io^g/day or 8.2 X io^^g/sec.,which is of the same order as the datum of table 2, remembering that theconstants of the apparatus are slightly different. The coefficients of trans-piration are, since a =11.5 cm.^(inside area), //= 11.5 cm. 2/f = 9.ocm. / = 20.5 cm. and, if the water hea
The diffusion of gases through liquids and allied experiments . tual viscosity, 77, of the intermolecular gasthrough which the hydrogen molecule supposedly transpires, if iV=6oX 10^,2r = 2Xio^ cm. (O. E. Meyer), is 77 = I /67r Nrv = 0.000413 The viscosity of hydrogen at ordinary temperatures is normally 91.5 X io.Hence the virtual viscosity of the intermolecular hydrogen would be fourand a half times larger than its normal viscosity.Using Millikans data for A and r, viz, iV = 2.64Xio^^ 2r = 2.28X10^ cm. the datum 2iVr = 6.03X10^^ replaces 2A^r= 12.0X10^^ whence 7j = 826Xio* Here in turn the
RM2AJBX3CThe diffusion of gases through liquids and allied experiments . tual viscosity, 77, of the intermolecular gasthrough which the hydrogen molecule supposedly transpires, if iV=6oX 10^,2r = 2Xio^ cm. (O. E. Meyer), is 77 = I /67r Nrv = 0.000413 The viscosity of hydrogen at ordinary temperatures is normally 91.5 X io.Hence the virtual viscosity of the intermolecular hydrogen would be fourand a half times larger than its normal viscosity.Using Millikans data for A and r, viz, iV = 2.64Xio^^ 2r = 2.28X10^ cm. the datum 2iVr = 6.03X10^^ replaces 2A^r= 12.0X10^^ whence 7j = 826Xio* Here in turn the
The diffusion of gases through liquids and allied experiments . c=i.43 and the final constants Vq = o.ooJ2 C.c./day, or io^*fi: = o.46 Thus the mica support has not changed the erratic behavior in the flotationin this vessel, in which the constants have fallen in about 90 days fromio^°K = 3.4, an enormously high value, to lo^V-= 0.46, an abnormally low-value, as compared with the usual result of about 10^^^ = 0.9. All attemptto interpret this exceptional record has remained futile, but it induced usto discard the double-tube apparatus in most of the experiments below, asbeing not only much mor
RM2AJBR9MThe diffusion of gases through liquids and allied experiments . c=i.43 and the final constants Vq = o.ooJ2 C.c./day, or io^*fi: = o.46 Thus the mica support has not changed the erratic behavior in the flotationin this vessel, in which the constants have fallen in about 90 days fromio^°K = 3.4, an enormously high value, to lo^V-= 0.46, an abnormally low-value, as compared with the usual result of about 10^^^ = 0.9. All attemptto interpret this exceptional record has remained futile, but it induced usto discard the double-tube apparatus in most of the experiments below, asbeing not only much mor