On the Resistance of Solids. 413 
+ 2. You may, thereby, with certainty, get fruit of every good 
sort, of which you wish to see the produce, in the next year. 
3. This method may probably serve to increase considerably 
the quantity of fruit in the country. 
The branches so operated upon are hung full of fruit, while 
the others that are not ringed, often have nothing, or very hitle 
onthem. This effect is easy to be explained from the theory 
of the motion of the sap. For, when the sap moves slowly in a 
tree, it produces fruit-buds, which is the case in old trees; when 
it moves vigorously, thé tree forms wood, or runs into shoots, cs 
happens with young trees. 
Though I arrived at this discovery myself, in consequence of 
trying the same process with a different view, namely to increase 
only the size of the fruit, but not to force barren branches, that 
were only furnished with leaf-buds, to bear, this latter application 
being before quite unknown to me; I will on that account by 
no means give myself out for the first inventer of this operation ; 
but I was ignorant of the effects to be produced by this method, 
and only discovered them by repeated experiments of my own, 
which I made for the promotion cf pomology. Frequent ex- 
perience of the completest success has confirmed the truth of 
my observations. Nor do [ think that this method is generally 
known; at least, to all those to whom I showed the experiment, 
the effect produced appeared new and surprising. At all events, 
that method, supposing it even to be an invention of older date, 
has, as far as [ know, not yet been fully described by any one, 
and published in print. 
a 
LXX. On the Resistance of Solids; with Tables of the specific 
Cohesion and the cohesive Force of Bodies. By Mr.THoMas 
TREDGOLD*, 
Definitions, {'c. 
6 Cozesron, or attraction of cohesion +, is that force by 
means of which the particles of bodies are held together. 
When the particles of a body cohere so slightly that they are 
easily moved among one another, in every direction, by a very 
small force, the body is called a fluid. 
* Communicated by the Author. 
4 Of the nature of attraction of cohesion, nothing is known ; but the phe- 
nomena prove the existence of that property of bodies to which the name is 
-applied. It is known that the parts of bodies do cohere, and that, when ac- 
eidental circumstances are excluded, a determinate force will separate then ; 
and this force being given, the theory of the resistance of solids consists 
in nothing more than applying the principles of mechanics to determin 
the power which will destroy that cohesion, when the direction of the power, 
aud the position and magnitude of the body, are given. 
When 
