696 Mr. J. H. Jeans on 
Values of o deduced from Viscosity. 
Gas K aX 105. 
Hydrogen <9). | 0000864 2°05 
olin 3.5. c.ceen cece ‘000165 181 
Water-vapour ...... | ‘000093 | v39 
Carbon monoxide...) ‘OOO1LG628 | 2-90 
Ethylene ............| ‘0000944 oT 
INitRogeM 5.78202 | ‘0001647 | 2°90 
NAY ebro ds ince aaa ‘0001714 2°86 
Nitrie oxide ~......... ‘000168 . 2°82 
Omyoen? s sc7iliei ee ‘0001873 2°81 
ANSON .20.% Pree | ‘000208 2°79 
Carbon dioxide...... | ‘QOOL4381 | S47 
| Nitrous oxide ...... | ‘0001381 3°54 
| Ethyl chloride ...... “000094 | 4°68 
Chisrime: it... ‘000128 | 4-11 
§ 6. As regards conduction of heat, the formula, as will be 
explained in the next paper, is 
d= 1-602 (xe,, 
where c, is the specific heat at constant volume, and « is 
simply an abbreviation for the right-hand member of 
equation (v.). This leads to the following table of values *. 
Values of o deduced from Conduction of Heat. 
Gas. / 4 (mean). | Fx 10". 
Hydroponic. .<:s00.3) 000353 ba eee 
DPSS  pstrne ans] YNO0512 214 
Mithylene™ 2. : <a. | ‘0000395 | 3°88 
Carbon monoxide... _ 0000498 2-74 
AG cua eh vi agate | ‘OOO005 19 272 
NibMIC XI: 3.50255.) ‘0000451 2-81 
OVROM oir. t | ‘QO00551 2°58 
Carbon dioxide......! ‘0000316 3°58 
Nitrous oxide ...... | ‘0000351 3°48 
§ 7. As regards the calculation of o from coefficients of 
diffusion, I have been content to examine only the four gases 
* T have taken Regnault’s values for cy, and the value used for 6 is the 
mean of three sets of experiments by Winkelmann, Graetz, and Wiillner, 
given in Landolt and Bornstein’s Tables, and in Meyer’s ‘ Kinetic Theory 
of Gases,’ English Translation, pp. 293, 295. 
