1S34.] 



Boats of River Navigation. 



137 



The few examples stated in this table have been taken indifferently 

 from a collection of the dimensions of boats used in twenty different 

 rivers in Europe, and from an equally numerous list of country-boats. 



The resistance that a boat meets with in passing- through the water 

 being proportional to its greatest section immersed, the last column in 

 the table has been added for the purpose of shewing the number of 

 maunds the boat can carry for each square foot in its greatest section. 

 This column is the best criterion by which an opinion may be formed of 

 the comparative advantages of the proportions of any two boats ; their 

 burthen, and the proportion between their resistance and their greatest 

 section, being the same. 



Dimensions of Boats proposed for the Navigation of the Rivers of Bengal. 



Burthen in 

 bazar mds. 



Length, 

 feet. 



•3 • 



u 



\ Q OJ <n 



M -w ~ i> 22 

 Jg " g 3 



q pa-s 



Greatest 

 section, 

 sq. feet. 



Ratio of 

 sectionto 

 burthen, j 



Remarks. 



1500 



72 



12 



f. i. 

 3 



11 



32 



48 



The weight of a boat 



1200 



66 



11 



2 9 



9 



26§ 



44 



with its crews & stores 



900 



60 



10 



2 6 



7 



22 



40 



on board is about one- 



650 



54 



9 



2 3 



6 



in 



37 



third of the load that 



460 



48 



8 



2 



5 



14 



33 



it will carry. 



310 



42 



7 



1 9 



4 



102 



29 



The size of the sail 



190 



36 



6 



1 6 



3 



8 



25 



is usually 30 sq. feet 



110 



30 



5 



1 3 



2 



H 



21 



for every foot of great- 



57 



24 



4 



1 



1 



n 



16i 



est section of the boat. 



From the last column of the first table it appears, that the average 

 load of a country-boat is 15| maunds for each foot of section, Avhile the 

 average of the English boats is 35 maunds ; and if one tracker is allowed 

 for every three feet of section, or six or seven men to track 100 maunds 

 in a country-boat, the same work can be equally well done by three men 

 in a boat of the improved proportions. This comparison is not strictly 

 correct, as the boats compared are not of the same burthen : but if the 

 country-boats in the first table be compared with boats of equal burthen 

 in the last table, the proportion will be found to be as 15§ to 32|. 

 This comparison shews how a saving of half the crew may be made. 

 The economy of using large boats instead of small, is in like manner 

 pointed out by the last column of the second table. It may be here 

 necessary to remark, that the stability, and of course the safety, of boats 

 of this proportion, when under sail, will exceed that of country- boats, as 

 much as the former exceeds the latter in length, the section of both 

 being the same, and the size of the sail bearing such proportion to the 

 greatest section as has been already remarked. 



Economy is not the only point to be considered in the conveyance 

 of goods ; regularity, cei-tainty, and expedition are of equal importance : 



