TRANSACTIONS OF THE SECTIONS. 91 
trade of Scotland from the most authentic sources, and also of the quantity of coals 
raised in the county of Lanark, and has arranged the information received on these 
subjects in two separate tables. 
»~On looking at the table constructed by Mr. Jessop for the iron trade, or for the 
iron produced by the blast furnaces in Scotland for the year ending October 1840, 
Dr, Watt finds that the increase in the annual quantity of pig iron smelted in that 
country in April 1845, amounts to 374 per cent, And there is every appearance that 
before another year expires a proportionate increase will be made in the amount of 
iron produced in Scotland. 
There are 2,047,000 tons of coal raised annually in Lanarkshire. The following 
is the manner in which that quantity is distributed for consumption :— 
Tons. 
It is known that the pig and malleable iron works annually consume about 1,000,000 
And that families and public works in Glasgow consume not less than ....,. 700,000 
The quantity of coal shipped at the harbour for the year ending April 1844, 
WAS ..eceeee VavanccvacscracUnses scr The sae<lAMsahEARSAAGSSOTACRaRAaaniaan *s2*¢926 aaaia se 120,000 
Quantity sent to Greenock by railway is ............64. Ma vadonisahiidnecuen a «tee riaa® 29,000 
Quantity sent by canal to the river Clyde «............00. canvass UNM sat oa o's 70,000 
Quantity consumed by steam-vessels carrying passengers and goods on the 
Clyde, to and from all quarters, is about ............ Movenedesomuenseronecasices 64,000 
Quantity consumed by the Clyde shipping company’s luggage- and tug-boats 10,000 
Quantity shipped at Port Eglinton per the Paisley canal....... Haren pccrArias 20 11,000 
Quantity consumed in the country arOUNd .,sycseasccessessercccrespeseeseesanses 43,000 
2,047,000 
Facts respecting the Iron Trade. By G. R, Porrszn, F.R.S. 
Sir J. Guest, of Dowlais Works, in evidence before Import Duties Committee, 
1840, stated that— 
Tons. 
The iron made at the beginning of this century amounted to... 150,000 
TeayA BOG vaheis cas ehesissiercsdasevceecavectscssetaccebsbeccsadectivecsscese) DOQ;000 
Tr LEDS noe Lees cen sevonsvevesescccnssnecesesdvovcecsacsesssnocsevessaegeos | | 402,000 
TeASL BRE lwas cs cheshyvassvsips speavhacsohagessinsisnacdpess osleed ceddacnensgneh)) BOd QO 
TDL GZS. Wastes cndaccanes devas Gets cvadneacrnanscercccnneasthpooeue sree 703,000 
Tra 1550 ndnceppapasestansepenrsdsegbesospenessssegpesicpessrapeesssessnsy= 19000,000 
.. 1,200,000 
So it ghd tA UG lead ME a ae a sessrseveseeee 1,500,000 
Mr. Porter further said, that Mr. Jessop, of the Butterley Works, estimated the 
annual produce in Great Britain, exclusive of Ireland, in 1840, at 1,396,400 tons, and 
that the quantity of coal used for smelting that quantity was 4,877,000 tons, besides 
2,000,000 tons for converting into wrought iron, To illustrate the importance of 
iron steamers, he could state that the Aaron Manby iron steam-boat, built in 1820, 
at the Horsley Iron-works, has been in use ever since, and the repairs to her hull 
have not altogether cost 50/. in those twenty-five years. A small iron steam-boat has 
been plying upon the Shannon since 1825. She is still in good condition. The 
number of iron steam-boats launched since 1830 is more than 150. Thesteam navy 
of the East India Company consists, in a great part, of iron—25 now in use in India. 
On the System of Colonization practised by the Irish Society. 
By J. Fiuercuer. 
On the different Methods employed to estimate the Amount of Population. 
By Prof. Pryme. 
These were worthy of being investigated ; because, in relation to history, some one 
or other of these methods was the only means available for interpreting facts. He 
enumerated many records of different countries and ages, to show that statistical in- 
formation, as a foundation for economic science, had been sought, though errors had 
been committed as to the right mode of attainment. There were four different bases 
