( 44° ) 
ner, or what is commonly call’d, the mufcular Coat of 
the Artery : which terminating here, the Tumour im- 
mediately encreas’d to 2 Inches in Diameter, and con- 
tinued of that Dimenfion, till it came out at the Neck, 
between the Clavicles ^ but then extended it felf circu- 
larly to a Diameter of above 3 Inches, the Covering of 
which was nothing elfe but the outer Coat of the fame 
Artery all along dilated from the Bafe, even to the 
Extremity of the Tumour. 
The Cavity was for the moil Part fill’d with a Sort 
of ‘Polypus , or Sarcoma ; in which neverthelefs there 
were three Sinufes, or Paflages, that were kept open by 
the confiant Influx of the Blood, and communicated 
near the Jlpex with one another } (that in the Middle 
being the larged,) and terminating in one towards the 
Extremity of the Tumour, not far from where it 
broke. 
Such was the State of the Aneuryfm in this Subjed, 
what it may be in others, future Enquiries mud de- 
termine. 
Y. Some Obf creations on Aneuryfms in general , 
and in particular , on the fore-going . (By F. Ni- 
cholls, M. Tr<d. of Anatomy 3 Oxon. & 
F. S. 
A N Aneuryfm is by all Authors defin’d to be a foft 
circumfcrib’d Tumor, in which there is a fenfi- 
ble Pulfation, cotemporary with the Pulfation of the 
Artery, to which it adheres. As it is certain, that any 
Tumor of what Kind foever, lying on, or adhering to 
any 
