It's very airy, isn't it, Maudie?

Recognising one of McGill's designs, especially an early one, can be quite difficult as he didn't always sign them. This example is clearly one of his because it is signed.

Unknown publisher No. 1009
Early 1910s

Finding the above card is useful confirmation when you come across the one below which is obviously the same ... but for some reason isn't signed although it appears to be exactly the same design apart from the colour difference due to different printers. It is also slightly cropped and the type font is different.

Published by Joseph Asher & Co., No 185
Postmarked 1911

If the top design had not been signed there could have been some doubt about whether it was a McGill or not especially with there not being a publisher's mark either. Although, I'm guessing, most collectors would have recognised his style. However, the bottom design would have been easier to attribute to McGill without a signature because it was published by Joseph Asher & Co.

So why was one signed and not the other?