INDEX. 
Rennell, James, Esq,. Some farther observations on the 
current that often prevails to the westward of the Scilly 
Islands, - 182 
Respiration , organs of, on their structure in animals which 
appear to hold an intermediate place between those of the 
class pisces and the class vermes, and in two genera of the 
last mentioned class, - 256 
Roget, Peter M., M. D. Description of a new instrument 
for performing mechanically the involution and evolution 
of numbers, • - - - 9 
S 
Satellites , the method of identifying them, - 351 
their periodical revolutions determined, - 348 
periodical revolution may be obtained from the observed 
angles of position, - 3 45 
a series of observations of those of the Georgian 
planet, including a passage through the node of their orbit ; 
with an introductory account of the telescopic apparatus 
that has been used on this occasion ; and a final exposition 
of some calculated particulars deduced from the observa- 
tions, - 293 
Scilly Islands , some farther observations on the current that 
often prevails to the westward of them, - - 182 
Sliding rule , a proposition pointed out that leads directly to 
the solution of every case to which that instrument can be 
applied, - 13 
Spinal marrow , experiments to ascertain its influence on the 
action of the heart in fishes, - - - 91 
Spirit of wine, its effects when applied to the spinal inarrow 
and brain, - - - - - 74 
— its effect upon the action of the heart, when 
applied to the surface, or inserted into the substance of the 
brain, - 427 
Stars, fixed, determination of the North Polar Distances, and 
proper motion, of thirty of them, - - 3$4 
Stoker, John, M. D. On an ebbing and flowing stream 
discovered by boring in the harbour of Bridlington, - 54 
