The standard of proof in cases of adultery is preponderance of probability, not beyond reasonable doubt.

( 1 ) THE petitioner has alleged that on the 16th August, 1959, he was married to the respondent No. 1, Devika Roy, according to the Hindu rites in Calcutta. After the marriage, two children were born. From April to November, 1969, while he lived in his quarters at Rishra, he had to leave Rishra for Calcutta in connexion with his official duties at 8 a. m. and return home at about 7. 30 p. m. The co-respondent, Dr. Saroj Sen, is the Medical Officer of the Alkali and Chemical Corporation of India, where the petitioner is employed as Project Manager. Dr. Sen used to treat the members of his family from 1966 to 1969. On the morning of 6th November, 1969, all of a sudden he returned to Rishra. On that date, Dr. Sen committed adultery with his wife in that quarters. The two children were taken away by their 'ayah' under the direction of Devika. So, he began to suspect them until to be sure about the same subsequently. Dr. Sen committed adultery with Devika from April, 1969, and has been living in adultery with her. On the 15th November, 1969, he along with his family members shifted to his quarters at 4 Aftab Garden, Alipore, Calcutta. Devika was then reluctant to leave Rishra. She lost all interest in the family including her children. Ultimately, she admitted that she had committed adultery with Dr. Sen. On the 16th December, 1969, she left the matrimonial home at Alipore. She also wrote letters admitting her guilt. Thereafter the petitioner did not share the bed with her. He did not make any connivance with her or condone such adultery. There is no collusion between the parties. The suit is for divorce and alternatively for judicial separation and also for the custody of the children.

( 2 ) RESPONDENT No. 1, Devika Roy, filed a written statement denying the petitioner's allegations. It has been alleged, inter alia, that the petitioner had illicit relationship with their 'ayah' and his cousin. There is collusion between the petitioner and Dr. Sen and they have been trying to get rid of her. She was tortured by the petitioner and ultimately, driven out of the house at Alipore. The petitioner insisted on her taking part in the dance in the Officers' Club. She did not agree to that proposal and a quarrel ensued between them. Dr. Sen used to visit their quarters. She requested the petitioner to ask Dr. Sen not to come to their quarters. But the former took no steps and began to abuse and torture her. After she had been driven out by the petitioner, his sister, Smt Kamala Sen Gupta, and her husband came to her father's house and stated that they would try for reconciliation if she wrote a letter to the petitioner admitting that she had committed adultery with Dr. Sen. She did not agree to that proposal. But her father prevailed upon her to do so and thereby on the 30th December, 1969, she wrote such a letter to her husband according to the dictation of Smt. Kamala Sen Gupta. But she did not receive any reply. According to the instruction of her father, on the 10th January, 1970, she again wrote a letter to her husband. But there was no response from his end. Her father was ailing and she felt much perturbed. Then on the 5th February, 1970, she again wrote a letter to the petitioner. But no response came from her husband. On the 26th or 27th February, 1970, Kamala Sen Gupta and her husband came to her father's place and told her that the first letter written by her had been missing and so, another letter was necessary. According to their request, and according to the instruction of her father, she wrote another letter to her husband.

( 3 ) CO-RESPONDENT No. 2 also put in a written statement and has stated that the suit is a collusive one. He did not commit any such adultery.

( 4 ) THE learned Additional District Judge has believed the petitioner's version and held that the case of commission of adultery is true. Devika also made voluntary admissions and wrote letters of her own accord. There was no collusion betwee