MORT'S MEAT-PRESERVING PROCESS.

Hawke's Bay Herald, Volume 13, Issue 1015, 19 January 1869, Page 2

MORT'S MEAT-PRESERVING PROCESS.

(By the Speoial Reporter of the "Australasian.") Deeply buried in the position referred to, behind Darlinghurst prison, is Mort's depot. daily, for ten or twelve hours, Nicole has been experimenting on the freezing process. So far as the latter is concerned, through the agency of ammonia, the -experiments have" been a success on land. Meat has been preserved for many months by this method of freezing, ammonia being the chemical base of the operation. Of this there can be no doubt. I have seen meat kept sound thus for twelve months, and Mr. Mort has assured me that he has repeatedly eaten meat so preserved ; and so far as the de- ! terioration thereof is concerned, he also | assured me that visitors at his table, have unwittingly partaken of meat from the frozen process in preference to meat killed and used in the ordinary way. Beef, mutton, and white meat have been thus eaten at his table, praised by his guests for delicacy of flavour, and on their being informed, after they had partaken of it, that it had been kept for weeks or months after it had been killed, they expressed their astonishment. Mr. Mart's testimony alone sets this part of the question at rest. I need not, therefore, describe the freezing system by using ammonia, because it is in abeyance— but merely state that it has been so far successful as to remain a good stand-by if the compressed or cold air process should not be so satisfactory. The principal objection to, freezing by ammonia is because the ammoniacal gases are so volatile, and in proportion as they are expansive they are dangerous. Much risk is combated with ammonia in operations on shore, and Mr. Nicole reasoned carefully and correctly when he concluded that if he had so much trouble with a highly expansive and powerful gas in the laboratory at Darlinghurst, the difficulty would be much greater at sea, should a small opening be made in the machinery circulating the ammonia around themeat cylinders. Ashesaidtome, an opening of the diameter of a pin's head might ruin the whole cargo, and perhaps an explosion would follow — damaging, or even destroying the vessel. After lengthy consultations between the capitalist, Mr. Mort; and the operator, Mr. Nicole, they agreed to lay aside the ammonia process and try that under consideration (viz., compressed air).

I shall not attempt to give the details of the process now almost elaborated, aa the patent has not been yet registered, but I shall give an outline only, in justice to the parties engaged. The moving power ia a small horizontal steam engine, occupying about 20ft. by 10ft„ and only 2ft. in height, excepting the cylinders. Its duty is merely to fill the cylinders for holding water — the principal cylinder being about lOffc. high, and it is filled up to many (say i seven) feet ; in the remainder of the top part of the cylinder is the air, which, when compressed and condensed, is made to pass through certain tubes, most ingeniously contrived, and which lead to one end of a drum 50ft. long by 10ft. high, and which is capable of holding fifty tons, by measurement, of meat. The drum is of planking3in. in thickness, and is tongued and grooved, and slightly curved. The frame of this large drum being of wood, and made air-tight, is then lined with galvanised iron, there being left 2in. space between the wood and the iron. About every 16in. apart on the outer portion of the iron lining there is a spiral division (that is between the wooden drum and the iron drum), and the compressed air forces its way from the first vessel or cylinder, through sundry tubes and valves into the spiral way made for it between the outer and inner drum, keeping the contents of the drum in a freezing state. The condensed, consequently cold, air passes spirally around the iron drum, the air entering at one extremity and leaving at the other, where it re-enters the chamber, in the first cylinder, where it was first compressed: Of course it is higher in temperature by the time it returns to the first chamber where it was first compressed, still it is used and forced to do duty again and again, as long as it is required. Thus it is that the compressed air, as a cooling agent of immense power, is repeatedly used and re-used, and none is wasted, if possible. One stroke of the piston of the steam-engine is sufficient to reduce the temperature of the air within the meat cylinder from 70deg. or 80deg. or 90deg. to below 32deg. That is, supposing the reader is standing in the cylinder in an atmosphere equal in temperature to that of the street near the dep6t, one stroke of the piston would positively freeze the clothes on his back- 4 - this has been | done in the meat drum cooled by the ammonia process. Some gentlemen were incredulous on this point; they entered the cylinder, and in less than ten seconds the clothes they had on their backs were cracking from frost, so they were glad to escape, and I should think would not like to repeat the experiment. Mr. Nicole assured me that one perfect stroke of the piston on the cold air system would cover the meat drum with frost, so tremendous is this power of cold air condensed. The object of the steam-engine is, therefore, to keep the water in the first cylinder up to the required height, whereby the air on tho top of this cylinder is compressed, and to open and shut valves as required. This is all that the steamengine has to perform. Each of the valves is within the immediate reach of the engineer in charge of the engine, and all of the works aro so simplified as to be within the control of any ordinary mechanical engineer. The compressed air system is, therefore, simple to a degree that can only be undrestood by the unscientific mind by inspecting the machinery. Half an hour makes the whole perfectly clear. The machinery w r herein the air is compressed is of immense strength, of course, to resist such an enormous pressure, which, in the stock chamber, is equal in compressing power to twenty atmosphores. The stock chamber, which bears the brunt of the pressure, and where the air is first compressed, is of thick iron, and braced with iron, so as to enable it to resist any amount of pressure likely to be brought to bear upon it. This is of the first importance, and of course the cylinder .vill be safely tested ere the ship is loaded, as this is apparently the only part of the engine which, if destroyed, can hardly be supplied at sea. The compressing cylinder or boiler will be equal to .more than a pressure of 6001bs. to the square inch, and therefore will, for strength and durability, be placed on as secure a footing as art, science, and mechanism can do for it. Every ship will require, under this process, to have such a steamengine and the required quantity of drums ; the latter will be built in the ship's hold ; tho wood is cut and curved by machinery, and the drums can be j knocked off with tho greatest ease and rapidity for 500 tons of meat in ten days. | A 500-ton ship can be loaded with meat in ono day. It is proposed to freeze the I meat at the termini of the different railI ways in the interior ; it will then be brought in its frozen state rapidly, and I placed on board ship in the huge drums, which will be in an atmosphere of not more than 32deg., and thus the meat will be conveyed to Europe, The cost of

freezing, carriage, and other incidental expenses is roughly estimated, at one penny for each pound of meat ; about 60s. per ton will be paid for freight to England, and the meat is expected to fetch, wholesale, 5d per lb. there, or about double the price of meat sold wholesale in Australia.

Suoh are the leading features of this great experiment, which, if successful, will, as stated, change the features of squatting matters in Australia. The promoters are of course sanguine as to the final results of their experiments. The greatest difficulty, Mr, Mort says, consists in getting the meat on board in a proper condition; once there, safe and sound, he apprehends the greatest obstacle has been surmounted. As for keeping it frozen aboard ship, this is the least of the difficulties ; he and Mr .Nicole think that the machinery at sea will bave to be stopped partially for want of work, so easy is i the cold process when once set in motion. j There is not the slightest anxiety in the minds of these gentlemen as to the machinery getting irreparably out of order at sea. If anything .less than bursting the compressing cylinder should occur it can be immediately righted by the engineer. The entire cost of the machinery and meat cylinders for a vessel of 500 tons is estimated at £3500. The cylinders will be in demand in returning from England for valuable freights, and the interest on £3,500 at 10 per cent, would only be £350 per annum. As a commercial speculation Mr. Mort (I need not say he is an excellent authority) is sanguine of success. Mr. Nicole laughs at all doubts. In a few days the machinery is expected to be practically tested, and I will inform you of the result. The plan may have to be modified as it proceeds to be practically applied, but these modifications are expected to be in the direction of saving room and expense. The basis is said to be sound enough, and in three years from the loading of the first cargo our surplus mutton will be so disposed of in England that it will cease to be a drug in the Australian market: At the expiration of the time named it is hoped that we shall be able to export by the same process all our surplus stock of Australian beef.