570 PHILOSOPHICAL TRANSACTIONS. [aNNO 1722. 



then it is very shallow water, for in a dry season the whole river runs in a 

 channel of not more than 15 feet wide. 



In my journey to Albany, 20 miles to the eastward of Hudson's river, near 

 the middle of a long rising hill, I met with a brisk noisy brook, sufficient to 

 serve a water mill; and having observed nothing of it at the beginning of the 

 hill, I turned about, and followed the course of the brook, till at length I found 

 it come to an end, being absorbed, and sinking into the ground, thence either 

 passing through subterraneous passages, or soaked up by the sand ; and 

 though it be common in other parts of the world for brooks and even rivers 

 thus to be lost, yet this is the first of the sort I have heard of, or met with, in 

 this country. 



A Letter from. Mr. Leuwenhoeck, F. R. S. concerning the Muscular Fibres in 

 several Animals, and the Magnetic Quality acquired by Iron, on standing for 

 a long time in the same Position. N° 37 I , p. 72. 



On viewing a portion of the flesh of a fat ox, as also the muscular fibres of 

 a cod-fish, and of a perch, the fibres being cut transversely, I could see in 

 them very distinctly the great number of small vessels, that ran along the length 

 of each fibre. And I have seen the same in the muscular fibres of the hinder 

 leg of a mouse, cut through transversely, and which are found of the same size 

 as the fibres of the ox. 



As to the small fibrils, mentioned in a former N°, that help to suspend the 

 testicles of a ram, I forgot to mention, that each of these consists of exceedingly 

 small vessels, which run parallel to its length. 



The iron cross, which is supposed to have stood on the steeple of the New 

 Church here about 200 years, having been lately taken down to be repaired, 

 and being informed that a piece of iron that has stood a long time in one situa- 

 tion would acquire a magnetic quality ; on which I desired a workman to pro- 

 cure me a piece of that cross, who accordingly brought me a bit of it, of about 

 a span long, and a quarter of an inch thick, which I applied both to a working 

 needle, and the needle of the compass, but without any efi^ect on the one or 

 the other. 



Some time after, the same workman brought me some other pieces, looking 

 like rusty iron, which he had broken off from the bottom of the cross, where 

 it had been fastened by four cross pieces bound down with iron, to an erect 

 piece of timber 9 inches square, and covered with lead in such a manner, that 

 no wet could get to it. This seeming rusty iron would take up several needles 

 hanging by each other, and appeared to have a stronger magnetic virtue than 



