Ancestry.ca has recently allowed free access to its records of Border Crossings from Canada to the U.S. 1895-1954, which I am gradually working through. They include Harry McIlhagga on 26 Jun 1916. I already had a record of him travelling from Liverpool to arrive on that date at New York, from the records of both findmypast.co.uk and Ancestry.co.uk. He was on the ship Cameronia. There is however extra information on his Border Crossing record. The New York port has the name Rouses Point. His class of travel is given as 'C'. His occupation is Commercial Traveller. He was born in Belfast, Ireland. His age is 37 (on the transcript though on the original image it may be 57). He paid for the passage himself. He was 5'10" tall, had brown hair and blue eyes. Crucially he gave his wife's name as Elizabeth, living in Belfast. I say 'crucially' for there are I think two Harry McIlhaggas born in the year 1879, which would have made them 37 in 1916.
The first Harry/Henry was the son of John McIlhagga and Elizabeth McCullough, born and baptised in Connor parish. At present I have no certain evidence that he survived and married. The second Harry (always as far as I can see known as Harry) was the son of William James McIlhagga and Ruth Woods of Belfast. In the 1901 Census he was an Invoice Clerk and in 1920 was described as a Linen Salesman when he married Sarah Laura Browne on 11 February at Lisburn Register Office and Legacurry Presbyterian Church. This marriage was four years after his 'Border Crossing' from Canada to the U.S. when he said his wife's name was Elizabeth. Both his place of residence and his occupation surely identify the crossing Harry as my second Harry, so we must assume that before he married Sarah he was previously married to Elizabeth. This is new information for us.