He has deposed to a large number of things, and the only points which it is necessary to mention are: (a) the normal period of gestation is 280 days, which period is calculated from the first day,,,,, of the last menstrual period; (b) where the hospital record .shows that the woman delivered of a child has normal labour and the child weighed 4 lbs and is living, it must have been conceived 270 days before the date of birth; (c) if a child is born within 169 days from the date of marriage it would not be of sufficient maturity to survive; (d) confirmation of a pregnancy within three weeks of conception is possible only by a biological test; (e) abdominal enlargement would be perceptible after the fourth month of pregnancy; (f) viability is described as the critical period of maturity and that this period is the 28th week of conception and explained that the viable period is called critical period because it denotes the development of the child 's tissues to the extent that it can have independent existence from its mother only after that and not before; and (g) a child born after the 28th week from conception would survive when special care and treatment is given to it.