ter which permits the introduction of a couch or bed has been
devised. This calorimeter has been built, tested, and used in a number
of experiments with men and women. The general shape of the chamber is
given in fig. 26. The principles involved in the construction of the
chair calorimeter are here applied, _i. e._, the use of a
structural-steel framework, inner air-tight copper lining, outer zinc
wall, hair-felt insulation, and outer asbestos panels. Inside of the
chamber there is a heat-absorbing system suspended from the ceiling, and
air thermometers and thermometers for the copper wall are installed at
several points. The food-aperture is of the same general type and the
furniture here consists simply of a sliding frame upon which is placed
an air-mattress. The opening is at the front end of the calorimeter and
is closed by two pieces of plate glass, each well sealed into place by
wax after the subject has been placed inside of the chamber. Tubes
through the wall opposite the food-aperture are used for the
introduction of electrical connections, ingoing and outgoing water, the
air-pipes, and connections for the stethoscope, pneumograph, and
telephone.

The apparatus rests on four heavy iron legs. Two pieces of channel iron
are attached to these legs and the structural framework of the
calorimeter chamber rests upon these irons. The method of separating the
asbestos outer panels is shown in the diagram. In order to provide light
for the chamber, the outer wall in front of the glass windows is made
of glass rather than asbestos. The front section of the outer casing can
be removed easily for the introduction of a patient.

In this chamber it is impossible to weigh the bed and clothing, and
hence this calorimeter can not be used for the accurate determination of
the moisture vaporized from the lungs and skin of the subject, since
here (as in almost every form of respiration chamber) it is absolutely
impossible to distinguish between the amount of water vaporized from
bed-clothing and that vaporized from the lungs and skin of the subject.
With the chair calorimeter, the weighing arrangements make it possible
to weigh the chair, clothing, etc., and thus apportion the total water
vaporized between losses from the chair, furniture, and body of the man.
In view of the fact that the water vaporized from the skin and lungs
could not be determined, the whole interior of the chamber of the bed
calorimeter has been coated with