ADJUSTIVE OPEEATING CHAIR. 107 



Mr. Owen exhibited a new form of Adjustive Operating Chair, and 

 made the following observations : — ' 



When a patient seats himself in the operating 

 chair, the first thing the dentist naturally pro- 

 ceeds to do, is to raise or to lower the seat of the 

 chair, if necessary, in order that the head may 

 rest at that level at which he can most easily and 

 most effectively perform his task. Of late years 

 this has been accomplished by mechanical arrange- 

 ments of various kinds, instead of with loose 

 cushions, as formerly; but in all the chairs that 

 have come under my observation, having the 

 advantage of a rising and falling seat, there is a 

 serious defect, which renders a certain amount of 

 complication indispensable. I allude -to the fact 

 that ivhen their seats are placed at the lowest 

 points, they are still so. high that the head of a tall 

 patient stands far above its proper resting-place, 

 and out of the reach of the dentist of average stature. 

 Now, as the w^ant of depression in the seat, 

 referred to above, and the several contrivances 

 by which it is counteracted, appeared to be 

 dependent upon the apparatus for elevating and 

 lowering the seat being placed under it, it oc- 

 curred to me that if a chair could be constructed 

 in which this should not be the case, — i.e., in 

 which the machinery should, for example, be 

 placed in the back, — ^we might be able not only to 

 raise, bvit also to depress the seat to any extent, 

 and thus to dispense with some complexity. In 



