Capital punishment may be distinguished into 1st, simple; 2nd, afflictive.
I call it simple when, if any bodily pain be produced, no greater degree of it is produced than what is necessary to produce death.
I call it afflictive, when any degree of pain be produced more than what is necessary for that purpose.
It will not be necessary, upon the present occasion, to attempt to give an exhaustive view of all the possible modes by which death might be produced without occasioning any, or the least possible quantity of collateral suffering. The task would be almost an endless one: and when accomplished, the only use to which it could be applied would be that of affording an opportunity of selecting out of the catalogue the mode that seemed to possess the desired property in the greatest perfection, which may readily be done without any such process.
The mode in use in England is far from being the best that could be devised. In strangulation by suspensions the weight of the body alone is seldom sufficient to produce an immediate and entire obstruction of respiration. The patient, when left to himself, struggles for some time: hence it is not uncommon for the executioner, in order to shorten his sufferings, to add his own weight to that of the criminal. Strangling by the bowstring may to some, perhaps, appear a severer mode of execution; partly from the prejudice against every usage of despotic governments, partly by the greater activity exerted by the executioners in this case than in the other. The fact however is, that it is much less painful than the other, for it is certainly much more expeditious. By this means the force is applied directly in the direction which it must take to effect the obstruction required: in the other case, the force is applied only obliquely; because the force of two men pulling in that manner is greater than the weight of one man.
It is not long, however, even in hanging, before a stop is put to sense; as is well enough known from the accounts of many persons who have survived the operation. This probably is the case a good while before the convulsive strugglings are; at an end; so that in appearance the patient suffers more than he does in reality.
With respect to beheading, there are reasons for supposing that the stop put to sensation is not immediate: a portion of sensibility may still be kept up in the spinal marrow a considerable time after it is separated from the brain. It is so, at least, according to all appearance, for different lengths of time in different animals and insects, which continue to move after their heads are separated from their bodies.