This section is from the book "The Gardener V2", by William Thomson. Also available from Amazon: The New Organic Grower: A Master's Manual of Tools and Techniques for the Home and Market Gardener.
What you forwarded was not a plant, as you supposed, but simply the fine fibrous roots of some plant - probably a grass - that had penetrated through one of the joints of the drain-pipes, and being constantly satured with water made excessive fine thread-like growth. We once saw a well opened near to which a Lombardy Poplar was growing, and one of the roots had penetrated into the well, and there formed an extraordinary mass of fine fibrous roots, of a similar character to the instance sent by you.
If Mr James M'Millan will oblige a subscriber with the address of the house from which the woollen netting referred to in page 349 of your Journal can be obtained, and add such particulars as will enable him to order the exact description, he will confer a great boon. - C. Z.