84

REVIEW OF GIAMMARCO

[5] equation

that the

Thomson-Berthelot

rule

must

be

valid

at

low

temperatures,

but that

at higher

temperatures

the

term

-ST lg

T

may

cause

deviations

when

SA

SB.

Doc.

13

Review

of

A.

GIAMMARCO,

"A

Case of

Corresponding

States

in

Thermodynamics"

("Un

caso

di corrispondenza in termodinamica,"

Il

Nuovo

Cimento

5

(5)

(1903): 377-391)

[Beiblätter

zu

den

Annalen

der

Physik

29

(1905):

246]

[1] [2]

If

one

has

a

liquid

(volume

v)

in

a

closed

cylindrical

tube

and above

it its saturated

vapor

(volume

v'),

and

one

plots v/v'

as

a

function of the

absolute

temperature

T

in

orthogonal

coordinates,

one

obtains,

depending

on

the

amount

of the enclosed substance,

a curve

that

has

a

maximum (v/v')max,

or a curve

that is

convex

toward

the

abscissa,

or one

(as

the

limiting case)

that

approaches

the critical

temperature

linearly.

The

author

investigated

ether,

alcohol

and

chloroform in this

way

and

finds that the

above

maxima

(v/v')max

lie

on a

straight line.

According

to

the

law

of

corresponding

states,

two

temperatures

T

and T'

at which

two

different substances

have

the

same

(v/v')max

must

be

corresponding temperatures

(the method

for the

determination

of

corresponding

temperatures), hence

T/Tc

=

T'/T'c.

Using

the

(absolute) critical

temperatures

of ether

(467°),

alcohol

(517°),

chloroform

[3]

(541°) (Bureau

des

Longitudes, 1902),

the

author finds

from

his

observations: