Coal.—­Over half-a-million tons of coal are used in Birmingham annually.

Cocoa.—­The manufacture of cocoa cannot be classed among the staple trades of the town, but one of the largest establishments of the kind in the kingdom, if not in the world, is that of Messrs. Cadbury, at Bournville, where nearly 400 persons are employed.  The annual consumption of cocoa in this country is estimated at 13,000,000 lbs., and the proportion manufactured by Messrs. Cadbury, who have houses in Paris, Sydney, Melbourne, Montreal, &e., may be guessed at from the fact that their works cover nearly four acres, and packing-boxes are required at the rate of 12,000 per week.

Copying Presses were invented by James Watt in, and patented in, May, 1780.  His partner, Boulton, had a lot ready for the market, and sold 150 by the end of the year.

Compressed Air Power.—­A hundred years ago every little brook and streamlet was utilised for producing the power required by our local mill-owners, gun-barrel rollers, &c.  Then came the world’s revolutioniser, steam, and no place in the universe has profited more by its introduction than this town.  Gas engines are now popular, and even water engines are not unknown, while the motive power derivable from electricity is the next and greatest boon promised to us.  Meanwhile, the introduction of compressed air as a means of transmitting power for long distances marks a new and important era, not only in engineering science, but in furthering the extension of hundreds of those small industries, which have made Birmingham so famous a workshop.  In the Birmingham Compressed Air Power Company’s Bill (passed March 12, 1884), the principle involved is the economic utility of centralising the production of power, and many engineers are of opinion that no other means can possibly be found so convenient as the use of compressed air in transmitting motive power, or at so low a cost, the saving being quite 20 per cent, compared with the use of steam for small engines.  The Birmingham Bill provides for the supply of compressed air within the wards of St. Bartholomew, St. Martin, Deritend, and Bordesley, which have been selected by the promoters as affording the most promising area.  In the three wards named there were rated in March of 1883, as many as 164 engines, of which the nominal horse-power varied from 1/2 to 10, fifty-nine from 11 to 20 fifteen from 21 to 30, six from 32 to 50, ten from 52 to 100, and four from 102 to 289.  Assuming that of these the engines up to 30-horse power would alone be likely to use compressed air, the promoters count upon a demand in the three wards for 1,946 nominal, and perhaps 3,000 indicated horse-power.  To this must be added an allowance for the probability that the existence of so cheap and convenient a power “laid on” in the streets will attract other manufacturers to the area within which it is to be available.  It is proposed, therefore, to provide machinery and plant