■VOL. XEV.] PHTLOSOPHICAL TRANSACTIONS. 513 



but from the region over the os sacrum, glutaei muscles, and between the thighs, 

 quite home to the pudendum, was growing a very large substance, which the 

 midwife and others called a wen, in shape very like the ventricle of a sheep, 'and 

 seemed, as to its colour and outward appearance, a continuation of the same skin 

 with the rest of the body, but very full of blood-vessels. It hung down behind 

 below the heels, and was larger than the whole body of the child itself. It felt 

 very soft, and seemed to have matter fluctuating in it ; but in the middle of the 

 whole was evidently felt a hard substance. The pudendum as well as anus were 

 in all respects natural, and both urine and stool were regularly discharged; but 

 the anus was placed much more forward, and immediately under the pudendum ; 

 so that the faeces were discharged in the same direction as the urine. 



The surgeon, Mr. Wills, made a puncture in the depending part of the tu- 

 mour, and drew off near 2 quarts of a palish red water, without any smell. The 

 orifice being left open, there was a continual issue of the same kind of water for 

 several days ; but by degrees it became more and more glutinous, and at length 

 whitish like pus, and very fetid. As the discharge was great, the child grew 

 weaker and weaker, and at the end of 1 5 days died. 



The next day he opened the tumour, and found, near the os coccygis, art 

 abscess within a cystis, in which were 4 ounces at least of white pus, exceedingly 

 stinking; and, on further examination, he found several cartilaginous joints, as it 

 were, somewhat resembling the tail of a sheep, continued from the point of the 

 os coccygis. These were about 2 inches long, and enveloped with a kind of 

 fleshy substance covered with a sort of fat; these, when cut through, appeared 

 exactly like the inner part of lamb-stones. From those depended a substance 

 like the head and neck of an embryo, the size of a large egg, which on being 

 opened contained somewhat resembling brain, and a kind of cerebellum in the 

 back part: it had a mouth and tongue on one side of the face, if it might be so 

 called, but no appearance of eyes or nose; however there was an ear pretty 

 evident. 



In the large tumour there hung a kind of loose membrane, which perhaps 

 might be part of a secundine. 



Of the Fluents of Multinomials, and Series affected by Radical Signs, which do 



not begin to Converge till after the Second Term. By T. Simpson, F. R. S. 



N° 487, p. 328. • ' 



Though the application of infinite series, and the quadrature of the conic 

 sections, to the inverse method of fluxions, has exercised the pens of the most 

 able mathematicians, and produced many curious and useful discoveries; yet no- 

 thing has been hitherto given, he believes, by which the fluents of radical mul- 

 tinomials and series, which do not begin to converge till afler the second tenu, 



VOL. IX. 3 U 



