WCP3171

[1]

Uig[,] Isle of Skye

Sep[tembe]r 16th 1898

My dear Sir

Since your letter reached me I have been touring about & not been able to write to you at length on the interesting subject to which you refer.

I may say that the subject of carrying fast ships on some form of oblique plane surface or numerous such surfaces has received some attention for a considerable time than people generally suppose.

[2]The Count de Lambert¹ of Paris has patented the idea and his specific arrangement of multiple planes of shutters or the leaves of tables² set at about 5º angle to the direction of suction, this angle being adjustable & I have seen a small double skiff made for him by Mr Phillips³ of Harrow (of flying machine fame) weighing altogether with the attendant 600 lbs developing about 10 I.H.P.[?] & travelling about 20 miles (land miles) per hour.

I was lead by calculation to think that about the same speed would be realized with an ordinary hull ^{& with} of the same weight & H.P.

He has so far made no very accurate determinations as to the coefficient of resistance.

He also tried a wide flat bottomed ship of larger size (somewhat like you describe & propose) with extremely light engines of 300 H.P. but the result was a failure and the boat could not be got to <surmount> ^on to the surface -

Maxim (Hiram) ⁴ patented the idea some 4 or 5 years ago but as far as I am aware he's obtained no practical results.

Several German gentlemen have written to me during the last 2 years, sending many drawings & calculations.

My own conclusion has been as follows & I may state it for what it may be worth[.] Carrying ships on planes if successful can only be applicable to ships of small size and fast speed. It may enable such [4] to reach very great speeds in smooth water.

It cannot ever be used for ships of say 5,000 to 10,000 tons just as a bird of ordinary construction of flesh and feathers but 1 ton weight could not fly.

Ships of 5,000 — 10,000 — 20,000 tons are carried with much less resistance when borne by their displacement up to speeds of 30, to 60, knots per hour.

The Livadsa[?] built for the Emperor of [1 word illeg] was flat bottomed & nearly floundered[?] in the Bay of Biscay by ^the striking of her flat bottom on the waives[sic?] which stone in parts — & she was afterwards condemned.

It is a very interesting subject and I am very much obliged to you for writng to me on this subject. It is fair to [1 word illeg] that developments may take place but it will be first [5] with ships of small size. In regard to the canal boat, possibly the canal was narrow and shallow & it would I think scarcely[?] be safe to conclude that the superiority of the flat bottomed boat would hold good in open water[.] Also possibly the form of the ordinary boat with which it was compared may have been unsuitable for the size, depth, & speed.

[6]In regard to creating[?] screws at an angle — In the first place the upward component of the thrust is in all cases a very small force compared with the height of the ship.

Even in the Turbinia⁵ it does not exceed 1 p^sf[?] & the effect on the trims or its lifting power is almost inappreciable -

[7] I wish I could have fallen in with your suggestions — but you will see that they have already been the subject of some not very [thorough] investigation — & perhaps Prof Langley's⁶ experiment and those of Mr Maxim & Mr Phillips represent the best works on this subject[.] You have doubtless read the formers works on the flight of birds & his coefficient of resistance of planes soaring [8] at high velosity through the air[.] All mathematicians from [1 word illeg] till a few years ago gave wrong coefficient untill Langley's ^{& another's} experiment gave the actual forces as observed by accurate experiment.

With my kind regards

Sincerely[?] truly | Charles A. Parsons⁷ [signature]

Alfred R. Wallace Esq