On Cupping. 131 



regarded as preliminary notions intended particularly to 

 enable students clearly to understand the use of the men- 

 surator triang'cs which will incessantly recur in the ap- 

 plications which we shall make of the calculus to the 

 laws of decrements. We shall now proceed more particu- 

 larly to the methods relative to this object; and as the 

 rhomboid, which likewise comprehends the cube, is of all 

 the kinds of parallelopipedon the most fertile in diversified 

 results, and at the same time that which is the most easily 

 adapted to the employment of general formulae, we shall 

 first give the theory of this solid ; after which we shall re- 

 sume that of the parallelopipedons of a different form. 



%* Understanding that an English Translation of the whole of Mi-.Hauy's 

 valuable work on Crystallography is now preparing for the press, we in- 

 tend, for the present, to suspend our labours upon it, as a full translation 

 cannot fail to answer the object we had in view, ^better than those disjoined 

 portions which can alone be admissible into the pages of a p6riodical work. 

 — Should the propo.scd translation not appear in some reasonable time, we 

 may hereafter resume our labours. 



XXI. Dr. Healy on Cupping. 

 To Mr. Tilloch. 



I No. 1, Clarendon-street, Dublin. 



hequest you will permit me to contradict an ob- 

 servation which has been made, in the Retrospect of Dis- 

 coveries, stating that the mode which I propose for cup- 

 ping without the assistance of the syringe, is so far from 

 new, that it occurred nearly £000 years ago, to Hero of 

 Alexandria, and that the figure is exhibited in the Maiht- 

 matici Vetercs.—l consulted the Parisian edition, and fiud 

 his contrivance (as described page 207) entirely different 

 from mine. Suffice it to say, a partial exhaustion is pro- 

 duced by the mouth from a secondary cavity, and two stop- 

 cocks are made use of. The syringe, which is an improve- 

 ment, and answers for the secondary cavity of Hero, is the 

 usual mode at present of producing the vacuum, and not, as 

 the observer states, the spirit lamp or tow. The apparatus 

 which I propose will still, I imagine, be found new, more 

 teconomical, and less complicated, than any that has been 

 hitherto adopted. 



Your much obliged, 



My i9, i8io. Robert Healy, M.B. 



I 2 • XXII. Obser- 



