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Green half-leather bound album measuring 380x280mm, with title as above stamped in gilt on front cover and containing 127 captioned prints, a mixture of amateur and professional work, recording the construction of the Mangla Regulator.

For detailed accounts of the Punjab canal systems, see 'Punjab Canal Gazetteers' (2 vols, Lahore, 1921-22). Volume 2 contains an account of the Mangla Regulator and the construction of the Upper Jhelum Canal:

The alignment of the canal through the difficult country between the Pabbi Hills and river Jhelum was carried out under the instructions of Mr Benton, Chief Engineer. There were many features of design of this canal which needed careful consideration. The choice of Headworks lay between the Changar site, involving the construction of a weir across the river, and the Mangla site where an artificial weir was unnecessary. For 4 years the hydraulic and geodetic data were collected and studied and finally it was decided to adopt the Mangla site. This invoved no weir across the river but meant cutting through a depth of over 100 feet of what appeared to be soft sand stone. It was necessary to use steam navvies on this work, and much other machinery and tramway plant...The question of the best design of masonry works at the point of transit of hill torrents across the canal alignment, of which there were a great many, called for much anxious thought. Among other works requiring careful consideration was the question of diverting the Bhimber torrent into the river Chenab instead of passing it across the canal. While these matters were being investigated, channel excavation was in progress. Once these engineering problems had been decided the progress was rapid, and in 1911-12 the expenditure, direct and indirect, exceeded Rs. 70 lakhs. By December 1915 the canal was sufficiently advanced to allow a supply being passed into it; and on 9th of that month His Excellency the Viceroy presided at the ceremony of the formal opening of the canal for irrigation... (vol. 2, pp. 3-4).

The canal takes off at Mangla, in Kashmir territory, at the concave side of a sharp bend of the river. The bank there is a vertical cliff about 100 feet high composed of alternate layers of soft rock and indurated clay. The river bed is scoured deep along the face of this cliff, whilst further downstream, where the river emerges from the hills and widens out in the low lands, a bar of shingle and boulders has been formed in the bed of the river by deposit from the current. The existence of this natural bar in the river bed rendered the construction of an artifical weir across the river unnecessary. The canal is fed from the deep pool in the river at the offtake whose minimum level of water surface is high enough for the purpose...The structure is unusually high by reason of the great variations of water surface level in the river. There was a difference of 41 feet between low water level and maximum flood level in the river before the canal was opened for irrigation. The Head Regulator has 20 vents, each 12 feet wide and in order to cope with the varying water surface levels of the river the vents are controlled by means of 3 tiers of gates working one above the other. The roadway over the regulator is at reduced level 917 or 66 feet above the floor. The length of the regulator is 562 feet and the width at base 67 feet.

The canal has been designed to carry 8,500 cubic feet per second at its head and to deliver 7,700 cubic feet per second at its head above the Khanki works at the head of the Lower Chenab Canal. The bed width is over 200 feet and the depth of water nearly 10 feet. Taking out in deep cutting from the river at Mangla the Upper Jhelum Canal follows a south-east course for 15 miles, along the slope of the Pabbi Hills, crossing a large number of torrents. Thence its course is south-west to Rasul at mile 50, passing in quick succession through deep cuttings and high embankments and crossing numerous torrents. As the canal gradient is very much flatter than that of the river, the difference between the bed of the canal and that of the river gets greater and greater, until at Rasul there is a difference of close on 80 feet. Here the canal curves sharply to the left round the extreme spur of the Pabbi Range, and takes an easterly course for 12 or 13 miles, along the southern slopes of the hills, passing across more torrents. Thereafter its course is generally south-east down to its outfall into the River Chenab at mile 89. In this last reach the canal gradually receded from the hills and the torrents crossed are of deltaic formation. (vol. 2, pp. 14-15).