Pipes, Joints, etc

As seen previously, it was normal to use 4-inch internal diameter hot water pipes, with other large and smaller diameter pipes being used as the situation dictated. Thomas Messenger standard diameter pipes were 4-inch, although in second half of the 1860s he often also used these in combination 1½-inch, 2-inch and 3-inch pipes. In the early part of the 1870s, it was almost exclusively 4-inch with some 2-inch pipes. Cast-iron hot-water pipes were at the time normally available in 9ft., 6ft. or 3ft. lengths. They normally came with a socket at one end and a small rim, known as a “spigot”, at the other. Some pipes had a trough cast on it, to allow it to be filled with water to provide more humidity, especially in horticultural situations.

At the time, it was normal to paint all pipes and other exposed pieces of equipment. The standard reasons given were firstly, that it prevented or slowed down oxidation and secondly, it provided a neater appearance. It seems that Thomas Messenger followed this practice, as on nearly every list of heating components was a varying price for pipe painting. Whilst this price obviously varied with the amount of painting required, there is no obvious “price per yard” calculation. For example, in 1872 he charged 10s. to paint 800 yards of 4-inch and 24 yards of 2-inch pipe, whilst at almost the same time charging another customer the same amount for 153 yards of 4-inch and 33 yards of 2-inch pipe.



The more complex the heating system the more bends, connections and other associated paraphernalia was required. It appears that Thomas Messenger used an almost standard range of accessories to both connect the pipes and negotiate the “route”. These typically included standard 90º bends, reducing sockets, 2-, 3-, and 4-way siphons, tees, plugs, collars, etc.

Initially hot water pipes could only be produced in relatively short lengths and had to be connected using various jointing solutions, including rope mixed with red and white lead; india-rubber rings which had the advantage of not only making good sound joints, but was easily removed, if required; iron cement was also popular particularly on joints close to the boiler. Until he developed his own-patented joint in 1871, Thomas Messenger’s standard method of connecting socket and spigot pipes was to use a cement joints. This consisted of alternate layers of ‘cement’ between the coils of rope yarn, filling in about half an inch of the socket with cast borings that have been moistened with vinegar, or with water in which a little sal-ammoniac[1] had been dissolved to make them rust quickly. Which type of ‘cement’ Thomas Messenger used is unclear, one such was a mixture of six parts dry slaked lime or whitening, one part of litharge[2] and two parts clean sand, these were mixed with raw linseed oil to make a putty[3]. By January 1870, he was already selling his jointed socket pipes. 6 and 9 feet lengths of 3-inch pipe were priced at 1s. 8d. per yard with 4-inch at 2s. 2d. per yard; 6 feet lengths of 2-inch pipes at 1s 2d. per yard; 2-inch elbows at 1s. 6d, 3-inch at 2s. 6d. and 4-inch at 3s.; 2-inch siphons at 2s., 3-inch at 3s. and 4-inch at 4s.; 2-inch patent joints at 1s., 3-inch at 1s. 3d. and 4-inch at 1s. 6d. However, most customers appeared to continue purchasing cement joints for the heating apparatus, probably because of the significant price differential. In 1872, the 4-inch patent pipes were 3s. 8d. per yard, 3-inch at 3s., 2-inch at 1s. 10d. and joints (4-inch?) 1s. 3d. each. This compared with 4-inch non-patent pipes at 2s 9d. per yard, 3-inch at 2s. 3d., 2-inch 1s. 4d. and joints at 5d. each.

Normally hot water pipes were placed along the bottom of a wall around the inside of a building and normally left exposed, i.e. not covered over. However, where pipes required being out of sight but still functional, they were often ‘cut’ into the floor and covered with a cast-iron grating, so as to allow the heat to permeate through. Typically, pipes were ‘hidden’ for cosmetic reasons such as in conservatories or churches; mostly they were placed under paths and walkways, particularly in churches and larger horticultural buildings. It was normal to bury two 4-inch pipes side-by-side. Where necessary single or quadruple pipes were also covered, as were narrower pipes, particularly if branching off an already buried pipe. Over time these cast-iron grating became very decorative and suitable to cover any situation, with the more ornate grating was usually reserved for situations that were more prestigious. Depending upon the design, gratings could come in various lengths, widths and sometimes in a ‘light’ or ‘heavy’ grade. Typically, they varied from between 2ft. and 4ft. in length and between 4in. and 2ft. in width; thicknesses was normally between ½-inch and ¾-inch.



Nearly all Thomas Messenger’s heating systems were designed to take a cold-water supply cistern, which he probably bought-in. These were of varying although unknown dimensions, normally priced at between 7s. 6d. and £1 10s. At the time, it was normal for supply cisterns to be of such as size as to be able of containing about five per cent of the total amount of water contained in the heating system.



  1. Sal ammoniac is a name of the natural, mineralogical form of ammonium chloride. The mineral is commonly formed on burning coal dumps, due to condensation of coal-derived gases. It is also found around some types of volcanic vent.

  2. A yellowish or reddish odourless form of lead oxide. Today it is chiefly used in the manufacture of storage batteries, pottery, lead glass, paints, enamels, and inks.

  3. A Practical Treatise Upon Warming Buildings by Hot Water by Frederick Dye.