This passage is from The Children's Bach by Helen Garner
Philip did not turn up with the car. This did not surprise Elizabeth. She took the bus to the airport. Vicki’s plane was late. Elizabeth walked up and down on the shiny tiles. She did not like people to observe that she was being kept waiting, and at least one girl was smiling at her in that shy, dawning way which meant she had seen Elizabeth on TV; but there was no decent coffee to be had, and no civilised place to sit. She measured her pulse on a tin machine outside the chemist shop. The reading she got was so low that she thought the thing must be out of order. She strolled into the shop, stole a twenty-five dollar Dior lipstick and a cheap plastic-covered address book and tried again: the adrenalin rush of petty theft showed. The address book would do for Vicki, if she hadn’t missed the plane altogether. She transferred the stolen items from her sleeve to her bag and went into the cafeteria for a bottle of mineral water.
Does "dawning way" in the sentence "one girl was smiling at her in that shy, dawning way" mean "the girl little by little became less shy and smiled more or became more friendly"?
Is the use of "altogether" in the sentence "if she hadn't missed the plane altogether" for emphasis?
Does "tin machine" in the sentence "She measured her pulse on a tin machine outside the chemist shop. The reading she got was so low that she thought the thing must be out of order." mean "a machine made of tin that measure heart pulse rate and other health factors"? And her heart rate was so low that she thought the machine must be out of order? I have never heard "tin machine".