Underwriters are liable for only such losses as are occasioned by some peril mentioned in the policy.

"It is only losses and damages of an extraordinary character that are covered,'11 and not consequences which in the ordinary course of events must occur, or are to be expected.12 But if the damage arise from a peril insured against, it matters not whether the force of that peril be great or small,13 providing it is sufficient to damage a seaworthy vessel.14 Damage due to the ordinary wear and tear upon the fabrics of a vessel is not insured against." 15 16