In the progress of the works of the Northern Light-houses, it soon became evident, from the diminished state of the funds, that the light-house duty of 1d. _per_ ton upon British vessels, and 2d. upon foreign bottoms, was too small. By the original act, also, this duty was only to be levied after the whole of the lights at the four stations had been exhibited to mariners; but the Board having found that it would be expedient to commence the collection of the duties so soon as two were lighted, resolved on applying to Parliament for a new act. [Sidenote: Act of 1788.] A bill was accordingly brought into the House of Commons by Sir Ilay Campbell, M. P., when Lord Advocate for Scotland, and _ex officio_ one of the Commissioners of the Northern Light-houses, which passed in the session of 1788, empowering the Commissioners to levy a duty of 1½d., or one halfpenny more _per_ ton upon British ships, and 3d., or one penny _per_ ton additional upon foreigners; and, in the mean time, to commence collecting half duties till the whole of the four light-houses mentioned in the former act were lighted, when the full duties were to become exigible. Already about L. 4000 had been expended on the light-houses of Kinnaird-Head and Kintyre. By this new act, however, the Commissioners being empowered to borrow a further sum of L. 3000, were not only enabled to forward the operations already commenced, but, with this additional duty, it was expected that they would soon be in a condition to answer the calls of the shipping interest for additional erections on the coast. _Island Glass._ [Sidenote: ~1789.~] Considerable progress had been made in the course of the former season with the erection of the Light-house at Island Glass in Harris, which was finished and lighted on the 10th day of October 1789, the following being its specification:--The Point of Island Glass, one of the Harris Isles, is situated in North Lat. 57° 50´, and Long. 6° 33´ west of London. Ru-Ushiness bears from the light-house, per compass, E. NE. ½ E., distant 8 miles; northern extremity of Shiant Isles E., ½ S., southern extremity of ditto E. by S. ½ S., distant 11 miles; Skerne Rock SE., ½ E., distant 3 miles; Skergraidish Rock S. SE. ¼ E., distant 9 miles; Point of Trotternish in Sky S. SE. ¼ E., distant 16 miles; Point of Vaternish S. SW. ¼ W., distant 15 miles; Dunvegan-Head SW. ½ S., distant 20 miles; Point of Roudil, at the entrance of the Sound of Harris, W. by S., distant 14 miles. The light-room is elevated 70 feet above the medium level of the sea, and will be seen from E. NE. ½ E., from W. by S., and intermediate points of the compass south of these points. [Sidenote: North Ronaldsay Light-house.]