352 



MR MILNE ON THE MID-LOTHIAN AND EAST-LOTHIAN COAL-FIELDS, 



APPENDIX F.— P. 292. 



Results of Experiments on a small scale of the Gas and Coke produced from 

 VARIOUS kinds of Parrot or Cannel Coal. 



Description ok Coal. 



Weight of 

 each charge 

 of Coal. 



Time re- 

 quired for I 

 Distillation. < 



Produce of 

 Gas. 



Proportion 

 of Gas pro- 

 duced per 

 Cm. 



Weight of 

 Coke pro- 

 duced. 



Weight of 

 Ashes when 

 Coke con- 

 sumed. 



Weight of 

 Combus- 

 tible Matter 

 in Coke, 



Consump- 

 tion'in one 

 Hour of a 

 Jet-flame 

 3 inches. 



Averao;e of two Charges of^ 

 J. and R. Aytoun's Coal V 

 (Fifeshirc), .... J 



Average of two Charges of Mr~J 

 Cuthbcrtson's Coal (East > 

 Lotliian), J 



Average of two Charges of Mrl 

 Marshall's Gilmerton Coal > 

 (Mid-Lothian), ... J 



Average of two Charges of 

 Halbeath Coal (Fifeshire) 



:'} 



Average of two Charges of 

 Wemyss Methcl Coal (Fife 

 shire), 



I 



Average of two Charges of Sir"l 

 Chas.jMenteath's Coal from > 

 Mansfield (Dumfriesshire), ) 



Average of three Charges ofl 

 Mr Mereer's Coal, from > 

 Dryden (Mid Lothian), ) 



Average of two Charges of\ 

 Sir Chas. Menteath's Rough '_ 

 or C«fcira/C'oal,from Mans- ( 

 field, ) 



Lb. 

 40 



40 



40 



40 



40 



40 



40 



40 



Hours. 

 2i 



2i 



2i 



2^ 



2J 



24 



Cubic Feet. 

 204 



192 



219 



216 



214 



240 



216 



216 



537 



613 



604 



599 



672 



604 



604 



Lb. 

 204 



^0 



201 



204 



19 



241 



Lb. 

 4 



2? 



SI 



lOi 



3J 



Lb. 

 15i 



17:? 



18 



14i 



134 



18 



8| 



21J 



Cubic Feet. 



•66 

 •78 

 ■81 



•72 

 •76 



•67 



•96 



Note. — The above experiments were made during the year 1837-8 in the premises of the Edinburgh Gas 

 Compan}', and I am indebted for the above statement of them to Mr Watson, the Manager. 



Mr Watson remarked, that the illuminating power of the gas is estimated inversely, according to the quan- 

 tity indicated in the last column. But this is evidently a very uncertain test. 



It appears that the results obtained in the manufacture of gas in large quantities, from any particular kind 

 of coal, seldom agree with the results of experiments (such as the above), conducted on a small scale. This 

 discrepancy arises chiefly from the great variation in the quality of the coals, though procured from the same 

 _seam, and out of the same pit. It is generally the best and purest specimens which are selected for experiments ; 

 so that there is necessarily less difference in the qualities of the coal experimented on, than there is in the im- 

 mense supplies furnished to the retorts. But even among the specimens of coal so selected, it is remarkable 

 how great a difference there is in the constitution of the coal, — arising from the different proportions in which 

 its elements exist in the same scam. 



