John Mitchell Moncrieff
Lieut-Colonel J. Mitchell Moncrieff (1865-1931) of Sandemann and Moncrieff
1865 Born son of Mitchell Moncrieff.
By 1894 Assoc. M. Inst. C. E.
1894 Awarded a Telford Premium, for "The Design and Construction of Dock Gates of Iron and Steel."
Engineer of Whitby Bridge.
"THE LATE LIEUT.-COLONEL J. M. MONCRIEFF.
Lieut.-Col. John Mitchell Moncrieff, whose death occurred on Saturday, January 10, at the age of 66, was well known in engineering circles as a specialist on the many problems connected with dock, harbour, and bridge construction. At the early age of 26, he began to practise, in partnership with the late Mr. J. Watt Sandeman, as a consulting engineer in the north of England, where his insight, enterprise and energy soon stood him in good stead and increased his circle of activities. Among the works for which he was responsible at this period were the construction of docks on the Tyne and at Blyth, the design of shear legs for the shipment of heavy guns from Messrs. Sir W. G. Armstrong, Whitworth’s works to Italy, the improvement of the harbours at Sunderland and Harrington, and the preparation of a scheme for bridging the Tyne by a bridge at Newburn. He also built a large pontoon dock, berth and wharves at North Shields, and constructed the launching and building berths for warships in Palmers’ Shipbuilding and Engineering Yard at Jarrow.
Shortly afterwards he came into prominence in connection with the building of the Redheugh Bridge across the Tyne, at Newcastle. The foundations of this bridge had to be formed within caissons under compressed air, the depths involved ranging from 65 ft. to 79 ft. below high-water level, and thus necessitating the employment of air pressures up to 34 lb. per' square inch. During the course of this work the door of :one of the material locks was forced open, causing the. air to. escape, but otherwise without serious incident. Recognising, however, that such an occurrence might cause the cylinder to drop, Mr. Moncrieff designed a working chamber in the form of a truncated cone with a very shallow cutting edge, above which a shelf 7 in. wide was provided to act as a brake should a slip occur.. This conical form ensured that the incoming earth would choke the cylinder and that the men would be forced into, the access shaft. In other respects, the bridge gave rise to a number of problems during its construction, and its completion was said at the time to have been-one of the most difficult feats ever carried out in this country in that class of engineering.
Mr. Moncrieff’s experience in this branch of civil engineering work was also utilised in the course of the inquiry into the accident, which occurred in 1907, during the. widening of Blackfriars Bridge. In this accident a staging collapsed while a caisson was being lowered into the- river, owing to the breakdown of two of the four' jacks which were being used to support the caisson during the lowering operation.
During the war, Colonel Moncrieff,- after serving for a time in the Royal Engineers, was appointed Director of Engineering Work, under the Controller of the Navy and the Controller of Merchant Shipping, and was responsible for preparing the original designs for the construction of the National Shipyards. For his. services in this capacity he was awarded the Commandership of the Order of the British Empire in 1918. On the conclusion of hostilities he resumed his consulting work as senior partner in the firm of. J. Mitchell Moncrieff and Partners, and among other activities acted in an advisory capacity to the Seaham Harbour Docks Company, and the Falmouth Docks Company.
Colonel Moncrieff was a frequent contributor to the literature of that branch of engineering in which he was interested. As early as 1893 he read a paper on “ Dock Gates of Iron and Steel,” before the Institution of Civil Engineers, for which he was awarded the Telford Premium, while other contributions to the Proceedings of this body included' communications on the “ Standardising of Loads and Stresses for Railway Bridges,” and “ Development and Status of Bridge Engineering." Articles from his pen appeared from time to time in Engineeeing, including one on “ The Practical Strength of Columns or Struts of Wrought and Mild Steel,” which was published' in our issue of June 6, 1902. He also received a gold medal for a paper on “ Commercial Dry Docks,” which was read before the North-East Coast Institution of Engineers and Shipbuilders. He was President of the Institution of Structural Engineers for the two years 1928-29 and 1929-30, and was elected a member of the Institution of Civil Engineers, for whom he acted as Examiner in Theory of Construction, in 1897. He was also connected with the Association of Consulting Engineers, of which he was chairman in 1924, and with the French Society of Civil Engineers, being president of the British Section of the latter body at the time of his death. His presidential address to the Institution of Structural Engineers was of an unconventional character, being of the nature, as he termed it, of gleanings of an historical character relating to structural engineering. In it he referred to and illustrated many interesting and quaint projects. While president of the same institution, he was invited by the Ministry of Transport to organise the British Section of the International Congress for Reinforced Concrete, which was held at Liege last year. He was also a Member of the Steel Research Committee of the Department of Scientific and Industrial Research."