The analyses of a text #2

The protagonist, Philip, who was born with a club foot, moved in with his uncle Mr. Carey after his mother's death.
He goes to King's School at Tercanbury.
Here he refers to the master Mr. Turner.
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He left off his clerical attire during the holidays and had been seen in Switzerland in gay tweeds. He liked a bottle of wine and a good dinner, and having once been at the Cafe Royal with a lady who was very probably near relation, was thenceforward supposed by generations of schoolboys to indulge in orgies the circumstantial details of which pointed to an unbounded belief in human depravity. Mr. Turner reckoned that it took him a term to lick boys into shape after they had been in the Upper Third; and now and then he let fall a sly hint, which showed that he knew perfectly what went on in his colleague's form. He took it good-humouredly. He looked upon boys as young ruffians who were more apt to be truthful if it was quite certain a lie would be found out, whose sense of honour was peculiar to themselves and did not apply to dealings with masters, and who were least likely to be troublesome when
they learned that it did not pay. He was proud of his form and as eager at fifty-five that it should do better in examinations than any of the others as he had been when he first came to the school.
[Of Human Bondage by Somerset Maugham]
1. I'd like to know if "in" is implied before "the circumstantial details."
2. I'd like to know if "that" is implied before "a lie would be found out."
3. I'd like to know what the first underlined "it" refers to.
4. And I'd like to know if the second underlined "it" refers to his form.