xlvi INTRODUCTION. 



stocked with sea-weed, rose so much in value, that, where 

 the plants did not grow naturally, attempts were made, and 

 not without success, to cultivate them by covering the sandy 

 bays with large stones. By this method a crop of Fact has 

 been obtained, we are informed by Mr. Neill, in about three 

 years, the sea appearing to abound everywhere with the 

 necessary spores. Upon the authority of Dr. Barry, during 

 the years 1790 to 1800, the quantity sometimes made was 

 3000 tons, and as the price was then from 9 to 10 per 

 ton, the manufacture brought into the place nearly 30,000 

 sterling, sometimes in one season. During the eighty years 

 subsequent to its introduction (from 1720 to 1800), the total 

 value will rise to < 595,000. These, and during the war, 

 when the price of kelp rose to <18 or 20 per ton, were 

 the palmy days of the manufacture, but since the peace the 

 demand has gradually slackened, and the price fallen away. 

 This result, so unfortunate for the owners of northern 

 estates and the numerous population, ' in Orkney alone 

 amounting to 20,000,' who found a profitable employment 

 in the manufacture, ' is to be attributed at first to the supe- 

 rior qualities of Spanish barilla, for the purposes of glass- 

 making and soap-boiling, but more recently to the almost 

 entire removal of the duty on common salt,' from the decom- 

 position of which soda is now so extensively manufactured 

 as to supersede kelp almost entirely for the above purposes. 

 In this ruinous state of the trade the kelp maker has had 

 recourse to the agriculturist, and experiments have fully 

 succeeded in showing the great value of kelp as a manure, 

 whence an extensive demand may eventually arise ; but it 

 is not likely that the price can ever reach its former rate. 

 But here again, soda obtained from rock salt comes into 

 successful competition with it, so that the prospects of the 

 unfortunate kelp grower seem hopelessly sunk ; unless the 

 demand, for the purpose of extracting iodine, be sufficiently 



