226 Transaction*. 



Leahy making a large double pair of ornamental gates of beautiful design 

 to demonstrate the quality of the iron, which was equal to Netherton Crown. 

 After a stoppage for some necessary repairs the fires were lit for a second 

 time. The best results obtained from one charge in the deoxidizer was the 

 manufacture of 6,751 lb. of iron from 14,625 lb. of sand ; the slag or cinder 

 amounted to 7,215 lb., the loss of cinder and waste in furnace being reckoned 

 at 659 lb., resulting in 46^ per cent, of iron being produced from the sepa- 

 rated sand. The operations were carefully watched by Messrs. James 

 Stewart and Edmund W. Otway, of Auckland, who on the 29th March 

 made the following report : — 



tc We have the honour to state that, as requested by you, we have 

 attended at your works erected at Onehunga for the reduction of the iron- 

 sand, for the purpose of examining in detail the whole process and obtaining 

 data for reporting on the cost of production. We are as yet unable to make 

 a complete report, but hasten to give you a few of the more important 

 results, and the deductions which may fairly be drawn from them. We, 

 hope shortly to report in a more exhaustive manner. 



" On Monday, the 19th instant, four retorts were filled with a mixture 

 of ironsand and charcoal, in the proportions of one measure of sand to two 

 of charcoal. Other four retorts were filled with a mixture of ironsand and 

 ground Waikato coal, in the proportions of two measures of coal to three 

 of sand, the intention being to put in 20 per cent, by weight of both char- 

 coal and coal in proportion to the sand. The above mixtures give that 

 percentage of coal, but more than that of charcoal, and in subsequent 

 operations in filling up the exact ratio of 20 per cent, was adhered to. 



" The fires were lighted on Monday night, and on Wednesday a small 

 charge was tried, but found not sufficiently carbonized or deoxidized- 

 either term appears correct. Puddling was therefore deferred until Thurs- 

 day, the 22nd, and was then commenced with the coal mixture principally. 

 But it soon became apparent that the coal was not in sufficient proportion 

 to carbonize the ore, and after working all day with a very poor result it 

 was determined to discharge all the coal mixture remaining in the retorts 

 and recharge with charcoal and ore. 



" On Friday work was resumed with better success, but, as coal mixture 

 had been used to fill up the shrinkage in the retorts remaining to be worked, 

 its presence still caused trouble, principally by the great amount of slag 

 produced, and iron dry and difficult to work to nature, causing the blooms 

 to be returned to the furnace once, and sometimes twice. 



" On Saturday the work went on very well, and if the draught of the 

 furnace had been perfect little could have been desired in the result. 



" We have worked out the result in two ways : (1 ) total sand ore worked 

 by both mixtures, against total yield of iron : (2) discarding the yield of 

 iron on Thursday, when the iron-ore was mixed with the coal, as obviously 

 the fairest view to take. The first result is 38 cwt. of iron from 149 cwt. 

 of sand, equal to 25-5 per cent, (very nearly) of puddled blooms. The 

 second view gives 33-25 cwt. from 98 cwt. of ore, equal to 34 per cent, 

 (nearly) of puddled blooms. 



" From the somewhat extemporized nature of the works, we feel con- 

 fident that the above percentage at least can be maintained by carbonizing 

 with charcoal. And by increasing the coal mixture to an amount equiva- 

 lent to 20 per cent, of carbon we have reason to believe a like result will be 

 obtained. 



" Discarding Thursday's run, the coal used in puddling and keeping up 

 the heat at night on Friday, Saturday, and Monday, including the coal 



