THE PARISH OF HALIFAX. Xxi. 



forty years is 47*09 ins. per annum, ranging from 30-45 ins. in 

 1887 to 63-07 ins. in 1872. Further details are shewn in the 

 table on the previous page, compiled from tables published by 

 James A. Paskin, M.Inst.C.E., Waterworks Engineer. 



Lying on the millstone grit rocks which intervene between 

 the coal fields of the West Riding and South Lancashire, the 



parish of Halifax does not possess the density 

 Population. of population of either area. The western 



townships (except near Todmorden) are very 

 thinly populated, but the central valley is occupied by a success- 

 ion of boroughs, towns and overgrown manufacturing villages. 

 It seems but a question of time for the main road traversing it 

 to become a continous street, lined with buildings. The mills 

 and hamlets have also followed the courses of the tributaries of 

 the Calder, and one in particular, the Hebble, has become almost 

 wholly urban in character. The population of the whole parish 

 is approximately a quarter of a million, of which the Borough of 

 Halifax claims a hundred thousand. This has its effect on the 

 Flora, mainly in the direction of extermination, but to a less 

 extent in the introduction of alien and casual plants. The 

 seeds of these are brought in wool, corn and other merchandise, 

 and plants alien to the British Flora spring up on the refuse 

 and tippings in the neighbourhood of mills, malt kilns, corn 

 mills, &c. In very few cases, perhaps in none, do these aliens 

 naturalise themselves and become permanent, just as very 

 few garden plants are able to hold their own in competition 

 with the indigenous flora. Similar plants may originate in the 

 goods' yards at the railway stations, and may flourish for a few 

 years on the railway banks. An embankment not only furn- 

 ishes an interesting object lesson in the succession of plants 

 that occupy it for some years after it has been made, but also 

 offers a permanent home of a peculiar character, exactly 

 adapted to the requirements of those that eventually win the 

 day. So it both shelters a few plants that are rare elsewhere, 

 and allows others to spread in continuous sheets in a manner 

 they cannot do off it. In the same way certain native plants 

 grow rampant about the ruins of disused mills in the cloughs. 



