4.90 REPORT—1904, 
known, and various formule have been suggested to reproduce these boiling- 
points. Thus Walker has proposed the formula T=aM”, where T is the boiling. 
point on the absolute scale of temperature, M is the molecular weight, and a and 
6 are constants. Ramage has this year suggested that this formula applies only 
to the CH, chain linkage, and that the influence of the terminal hydrogen atoms 
is considerable in the case of the lowest members, but diminishes as the chain 
lengthens, and becomes eventually either constant or negligible. In other words, 
the lower members of the series cannot be regarded as truly homologous, and that 
is a point which is, I think, important to bear in mind. Ramage suggests a new 
formula, T= a[M(1—2-")]}, where a is Walker’s constant, 37:3775, and 7 is the 
number of carbon atoms in the molecule. He assumes, however, a constant 
difference for CH, in the case of the alcohols, the aldehydes, and the ketones, but 
I doubt whether the boiling-points of the last two classes of compounds are yet 
sufficiently well established to allow of any certain conclusions being drawn from 
them. 
I am inclined to think that it may be useful to regard the value of A (the rise 
of B.P. for an increment of CH,) as being mainly a function of the absolute tem- 
perature, and I would provisionally suggest the formula A = sonar where A is 
the difference between the boiling-point, T, of any paraffin and that of its next 
higher homologue. Taking the boiling-point of methane as 106°-75 abs., the values 
for the higher members agree better with the observed temperatures than those 
given by Ramage’s formula, as will be seen by the table below :— 
Boiling-point (abs. temp.) 
a sceeani Calculated. | ne Calculated. 
Bere Ramage | Young | A 
CH 1083 | 105°7 —26 | 106°75 | = = 1:55 
OH, - 180-0 1773 Joo 27% | 1777 —2°3 
OjHy. 228°0 231:9 | +39 229°85 + 1:85 
C,H,, 274-0 275'6 Pa sth 6 aces 272°6 —14 
C,H, 309°3 | 312-2 | ‘+2°9 309-4 +01 
Cane 341-95 343°9 +1:95 341°95 0 
C,H,, 8714 372°3 +0°9 3713 | —O1 
C,Hie 398°6 398°3 -03 398-1 | —O5 
C,H, 422°5 422°5 0 422°85 + 0°35 
Ohales 4460 4452 —0°8 445°85 — 015 
C,H, 467°0 466°8 —0:2 467°35 + 0°35 
C,.Ho, 487°5 487°3 —0:2 487°65 +015 
ChE. 507:0 507-0 0 506°8 —0'2 
Ole e, 5255 526°0 +0°5 5250 —0°5 
Cie 543°5 544°2 +07 542°3 —12 
Cry 560°5 561°9 +14 558°85 —1°65 
CirHg, 576:0 5790 +30 574-7 —13 
OF ‘ si 590°0 595°7 +57 589°9 —01 
C,H yo m : 603-0 611°9 +89 604°5 +15 
I do not wish, however, to lay much stress on the actual form of the equation, 
or on the particular values of the constants; the chief point I wish to call atten- 
tion to is that A may be regarded as a function of the temperature. 
Suppose that we replace a terminal atom of hydrogen in each normal paraffin 
by chlorine, so as to form the homologous series of primary alkyl chlorides. The 
boiling-points of these chlorides are much higher, and the differences, A, are much 
smaller than for the corresponding paraffins, but the gradual fa}l in the values of 
A as the series is ascended is unmistakable. The same remarks apply to the 
bromides and iodides, the boiling-points being still higher and the values of A 
smaller, 
But the point of chief interest appears to me to be this: if the values of A for 
