"10. It is thus clear that Section 114 of the Evidence Act enables the Court to presume that in the common course of natural events, the communication would have been delivered at the address of the addressee. Section 27 of the GC Act gives rise to a presumption that service of notice has been effected when it is sent to the correct address by registered post. It is not necessary to aver in the complaint that in spite of the return of the notice unserved, it is deemed to have been served or that the addressee is deemed to have knowledge of the notice. Unless and until the contrary is proved by the addressee, service of notice is deemed to have been effected at the time at which the letter would have been delivered in the ordinary course of business.