med hy iJie Natives on tlie Coast of Coromandk. 6S 
a number of handspikes, capstan bars, or other levers, might be 
inserted and left standing out, like handspikes in a windlas on 
board ship ; or these lev^ers, instead of being lashed in along with 
the main spars of the raft, might be attached to the outside, and 
made to act as in the power familiar to the practical seaman^ 
under the name of the Spanish mndlas. In this way, the use 
of slew-ropes would be superseded ; and, by lengthening these 
levers, the power might be increased at pleasure. It ought not 
to be forgotten, that the smaller the diameter of the raft, com- 
pared with the length of the levers, the greater will be the power 
of purchasing the anchor. In practice, therefore, it may be ad- 
visable to make that part of the raft over which the buoy- 
rope passes, as small, and those parts which bear the levers, as 
large as possible. 
Art. XI . — Examination of some Compounds xohlcli depend up^ 
on very weah Affinities, By Jacob Berzelius, M.D. F.R. So 
and corresponding Member of the Institute of France. Com- 
municated by the Author. 
So long as we confine our attention to those combinations 
which owe their existence to very strong chemical affinities, we 
find a striking simplicity and a constant analogy in their compo- 
sition : but, if we begin to examine those combinations which 
depend upon weak affinities, we find, that, as we proceed, the 
modes of combination continue to increase in number and intri- 
cacy. Salts formed by the union of strong acids, with salsifiable 
bases, belong to the former of these classes ; whilst a great part 
of the productions of the mineral kingdom, where bodies slightly 
electronegative perform the function of acids, belongs to the lat- 
ter. This class includes also some otlier very weak combina- 
tions ; those, namely, which take place among compound mole- 
cules of the second or third order, and vyhich form salts of a 
double, sometimes perhaps of a triple base. It is sufficiently as- 
certained, that chemical affinity rapidly diminishes as the num- 
ber of combining atoms augments. Thus, the affinity of com- 
pound molecules of the first order is much weaker than that of 
elementary bodies ; and the difference between the affinity ex- 
