This is an antique Idris Ltd, London, soda bottle. The clear pop or mineral water bottle likely dates around the 1920s as a machine made line goes to the top of the bottle. The bottle is embossed on the bottom, "The Property of Idris Ltd, London - Not to be refilled - Reg'd No. 855590 UGB" (Please note the number is difficult to read and may be incorrect.. See photo closeups). My father, an avid bottle digger, found the bottle more than 40 years ago in the ruins of an old home in Virginia. The bottle is in great shape, free from breaks or cracks. Clarity is very nice with the exception of a few rough spots and stains from long term exposure. (See photos). Idris Co was founded in 1873 In the Idris Mountains of Wales as a producer of mineral and aerated water. In 1880 they began producing flavored beverages such as ginger beer, lemon squash and fruit syrups. They also produced wine. I have not been able to find a bottle similar to this one on line so don't know what kind of beverage it held. I must assume it is also rare for the same reason. See the websites below for more information about Idris. https://www.gracesguide.co.uk/Idris_and_Co http://www.brynmawrhistoricalsociety.org.uk/idris-soft-drinks/4594103485