What was held in the case of Clark v. Maclennan in regard to negligence?

In Clark v. Maclennan it was held that although in an action in negligence the onus of proof normally rested on the plaintiff, in a case where a general duty of care and that failure was followed by the very damage which that precaution was designed to prevent, the burden of proof lay on the defendant to show, first that he was not in breach of and duty and second if he failed to prove that he had not been in breach of duty, that the damage suffered by the plaintiff did not result from the breach. Also, conformity with the general and approved practice will generally lead to the interference in favour of defendant.