In years of dominance of natural law and philosophy of laissez-faire the carrier was able to protect his interests by broadly drafted clauses, with very wide range of options regarding to places where it was lawful for ship to call to. The cargo interests, on the other hand, were resolute in restricting the meaning of such provisions within the following limits:
a) description of voyage
b) justification of departure from the direct route
c) the justice of the case .
Per Lord Mansfield in Lavabre v Wilson (1779) 1 Dougl. 284 at p.288:
… going to any port, though out of the course of the voyage, is, in the eye of the law, no deviation, if necessary for the safety of the ship.
By Cockburn CJ in Scaramanga v Stamp (1880) 5 CPD 295, CA.
… deviation for the purpose of saving life is protected, and involves neither forfeiture of insurance nor liability to the goods’ owner in respect of loss which would otherwise be within the exception of 'perils of the seas'. And, as a necessary consequence of the foregoing deviation for the purpose of communicating with a ship in distress is allowable, inasmuch as the state of the vessel in distress may involve danger to life. On the other hand, deviation for the sole purpose of saving property is not thus privileged, but entails all the usual consequences of deviation…
Deviation for the purpose of saving property stands obviously on a totally different footing. There is here no moral duty to fulfil, which, though its fulfilment may have been attended with danger to life or property, remains unrewarded. There would be much force, no doubt, in the argument that it is to the common interest of merchants and insurers, as well as of shipowners, that ships and cargoes, when in danger of perishing, should be saved, and consequently that, as matter of policy, the same latitude should be allowed in respect of the saving of property as in respect of the saving life were it not that the law has provided another, and a very adequate motive for the saving of property, by securing to the salvor a liberal proportion of the property saved - a proportion in which not only the value of the property saved, but also the danger run by the salvor to life or property is taken into account, and in calculating which, if it be once settled that the insurance will not be protected, nor the shipowner freed from liability in respect of loss of cargo, the risk thus run will, no doubt be included as an element. It would obviously be most unjust if the shipowner could thus take the chance of highly remunerative gain at the risk and possible loss of the merchant or the insurer, neither of whom derive any benefit from the preservation of the property saved…
J. & E. Kish v Charles Taylor, Sons & Co  AC 604 per Lord Atkinson:
On the whole, therefore, I am of opinion that a master, whose ship is, from whatever cause, in a perilous position, does right in making such a deviation from his voyage as is necessary to save his ship and the lives of his crew, and that while the right to recover damages from breaches of contract, and all wrongful acts committed either by himself or by the owners of his ship, is preserved to those who are thereby wronged or injured, the contract of affreightment is not put an end to by such a deviation, nor are the rights of the owners under it lost.