34 nEroiiT — 1884. 



penses of publication, and therefore the price will be considerably less 

 than that which would pay for the printing. The printers for the India 

 Office still had about fifteen pages in type, and permission was obtained 

 through General Strachey to have copies struck off from these and from 

 the sheets of the long period forms as they were ready. The remaining 

 eighty pages of the work have been copied by photo-zincography at the 

 office of the Ordnance Survey at Southampton. Mr. Roberts kindly 

 corrected a few errata with the pen before sending the originals to be 

 photographed. I have to thank the officers of the Royal Engineers in 

 charge, and especially Major Bolland, R.E., for the attention which was 

 bestowed on the matter. 



It was through the exertions of General Strachey that permission 

 was obtained to have this work done at Southampton ; and in consequence 

 of a correspondence between the India Office, the Board of Works, and 

 the Treasury this part of the work has been done free of charge, on the 

 condition of my supplying a certain number of copies to the Admiralty. 

 I am also assisted in the publication by a grant from the fund admini- 

 stered by the Royal Society. 



It is to be regretted that notwithstanding this requisition for compu- 

 tation forms it appears that the Admiralty is satisfied with the old method 

 of tidal reduction, and has no intention of making any contribution to 

 our tidal knowledge by instituting harmonic analysis of tidal records. 



Dr. C. Borgen, of Wilhelmshaven, informs me, in a letter, that the 

 tides of the North German Sea are now being reduced according to the 

 harmonic method, presumably for the Imperial Admiralty, and he writes: 

 'It is intended to publish the results for the German coast in exactly the 

 same manner as you propose for the English, so that they may be strictly 

 comparable. The calculation for Heligoland, 1882, is begun and will be 

 completed in about a month or so (from the end of June 1884).' 



I learn from M. Bouquet de la Grye, of the Bureau des Longitudes, 

 that he has been engaged for some time past in the reduction of a large 

 mass of tidal observations according to an harmonic method devised by 

 himself, and that the work approaches completion. 



Mr. Neison, now in charge of the Natal Observatory, expresses his 

 intention of reducing the tidal observations at Natal according to oar 

 methods, and I shall supply him with computation forms. 



Mr. Gill, Astronomer Royal at the Cape, will also undertake the 

 reduction of the tides of the Cape Colony, and will be supplied with 

 forms. 



There seems to be a possibility that some of the Australian Colonies 

 may be induced to take up the matter. 



Major Baird will probably undertake to draw up a manual of practical 

 instructions for the erection of continuous tide-gauges, and the practical 

 experience of one who has supervised so much work of the kind will prove 

 of great value. 



The fate of the tide-gauge ei'ected by the Portuguese Government at 

 Madeira affords a proof that it is not of much use to direct the establish- 

 ment of a tide gauge, unless the work bo placed in the hands of some one 

 who has had experience in the matter. It is said that the tube which 

 was sunk into the sea from the Loo Rock at Madeira was open at the 

 bottom, and that the platinum wire attached to the float was broken at 

 ©nco by the pumping up and down of the water. I believe that nothing 



