Tag Archives: Sentinella

Spirometer, Sentinella, 1940

Spirometer_Sentinella_1940

From: Breathing capacity and grip strength of preschool children, by Eleanor Metheny, University of Iowas Studies, Studies in Child Welfare Volume 18, No. 390, 1940, page 20.

“…the spirometer shown in Figure 1 was constructed by J. G. Sentinella of the State University of Iowa.  The upright cylinder is made of brass tubing 1/8 inch in thickness covered with black crystallizing lacquer.  The uprights and pulleys are made of brass, with a smooth finish. The metal tubes are also made of brass. The bell is made of 1/65 inch brass sheeting, and has a clearance of 1/16 inch as it moves up and down.  Fifty pound test linen fish line runs over the pulleys and connects the bell with the counterweights. The balance of the bell and the counterweights was carefully worked out so that the bell offers little resistance to upward movement. A slight puff is sufficient to start it on its upward rise.

“Soft rubber tubing with .8 cm inside diameter is attached to one extension of the inside vertical pipe, and the second extension is fitted with a cork which is removed when the air is being let out of the tank. The faucet attached to the lower part of the tank is for convenience is emptying water from the spirometer. The individual wooden mouthpieces manufactured by Stoelting and Company for use with a large spirometer fit the rubber tubing.  A new mouthpiece was used with each child.

“The vertical scale is graduated 2 cubic inch units. The distance between two cross lines is .1 inch, so that the record may be read to the nearest cubic inch.

“The spirometer measures 21.5 inches from the base to the top of the pulleys and has an over-all diameter of 5.4 inches.  It weighs 11 pounds when empty, and can be transported easily.”