Where a loss has two proximate causes, one of which is within a marine insurance policy and the other expressly excluded, the exclusion takes effect to exempt the insurer from liability. However, where it was established that a proximate cause of the loss was a fortuity occurring during the period of cover, there was no room for inherent vice to be treated as another proximate cause of the loss. The fatigue cracking which had occurred to the goods during transportation had been proximately caused by resonant vibration which had been an external fortuitous accident and the claim under the marine policy succeeded (European Group Ltd v Chartis Insurance UK Ltd).