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known that grease or oil of almost any kind is very fatal to insects, lice, &c., and we decided to give it a trial on ticks. This being a great cotton country, we have cotton-seed oil in abundance. In our earlier experiments we added to cotton-seed oil 10 per cent. of crude carbolic acid and 5 per cent. of pine tar, but we found later that this is not necessary or desirable. Cotton-seed oil is on the market in several grades-the crude, which is often darkcoloured, probably due to resins, and the refined, which is very superior. The sp. gr. is about 920-930. We used the crude only in the vat. We fill vat with water, and aim to have a layer of oil to 1 inch in thickness on the water. This requires about 100 gallons of oil. The cattle are forced to swim through, and on emerging from the vat become covered perfectly with oil. This has no apparent effect on the cattle, but is exceedingly fatal to the tick. We are having some trouble with it, however. Our water is from an artesian well, and is alkaline, due to some salts of soda, so that after the violent agitation of the oil by the cattle it shows a tendency to emulsify after several weeks' standing. We found, also, that common salt greatly delayed this process, so that in our last series of experiments we used 5 per cent. of salt, and the oil kept well for three months. The oil-dipping,' as we call it, is very much superior to anything we have found. For good work, 100 gallons of oil should be on the water; for perfect work, 150 gallons. Cotton-seed oil is valued at 20 to 30 cents. per gallon. We dip our cattle two or three times during the tick season, which extends from 1st July to 1st November. In 'oil-dipping' the cattle must come through the vat in single file'-crowding produces imperfect work. Our vat so arranged will dip about 1,000 head per day. The wilder the cattle are the better. In our experience we have never injured any animals (except in the carbolic dips noted above)-no broken legs, no abortion, none drowned. I believe we can make the oil-dipping perfect. I beg to add some notes of failures :1st. Kerosene emulsion, no practical value. 2nd. Crude petroleum, irritates the skin, emulsifies with water. 3rd. Resin oil, no value. 4th. Corrosive sublimate, too dangerous, and not very fatal to ticks, even in solution 1.250 of water. 5th. Tobacco sheep-dips, no practical value. We are at present studying other oils. The most promising is West Virginia black, a black mineral oil. We will use it in the coming season. It does not emulsify, and it is cheap, costing us 14 cents per gallon, delivered in small lots of 50 to 100 gallons. It is very fatal to the ticks. We are also using paraffin oil, but it is not so promising. I beg to suggest that before you order any quantity of dip or oil that you secure a sample (say, 1 gallon) and test it on a cow, also with the water you intend To do this, fill a pint bottle half full with the water, and add about half an inch of the oil. Insert a stopper, and shake the bottle violently several times a day for a week or ten days. You can soon decide if it will be suitable for your purpose."

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Inoculation.

Amongst the conclusions arrived at during the Intercolonial Tick Conference (August, 1896), one was to the effect that "No satisfactory experiments in inoculation have been made, and the information concerning the disease is that an animal enjoys no certain immunity from a previous attack."

The discussion which led up to this was, of course, the contention whether, by inoculation the blood of a diseased beast into a healthy beast, and so causing a mild fever in the healthy beast, it would subsequently be immune from contagion by ticks.

The following brief recital of experiments in inoculation of different animals is taken from reports by Pound and Hunt, and Kilborne and Smith::

Bullocks.-Dr. Hunt reports the following experiment of inoculation by gradation from one beast to another:-"Ten cubic centimeters of blood were taken from a beast which was dying of tick fever and injected into the jugular vein of a healthy beast, which we will name A. When he sickened his blood was injected into bullock B, and so on down to seven or eight removes. Bullock A died, but the others lived, and were sent with the lot mentioned down to badly-infested land at Townsville." It was found that the inoculation behind the shoulder was as effective as in the jugular, but Dr. Hunt has as yet no fixed opinions about the efficacy of inoculation. Kilborne and Smith withdrew blood from the jugular vein of an infected beast when alive, and injected (22 cc.) it into a healthy animal, The whole operation lasted one or two minutes. This produced disease, which lasted four days, and the animal recovered subsequently. Afterwards, other experiments of a similar nature were conducted with varying results so far as recovery was concerned, some dying and others surviving. In concluding, these authorities say :- With these positive results before us we need not hesitate to make the statement that there is something in the blood of cattle during (Bovine) tick fever which, introduced into the body of healthy susceptible cattle, gives rise to the disease. These inoculations show, also, that a comparatively small quantity of blood from diseased cattle placed under the skin (of healthy beasts) is capable of causing a severe and fatal infection."

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Horses.-Dr. Hunt tried the inoculation of blood from a diseased bullock into horses, giving 10 centimetres to each horse, the jugular vein in each case being the recipient. The horses were not affected, and displayed no rise in temperature.

Sheep.-Dr. Hunt tried a similar experiment upon sheep to that upon horses, with the result that the sheep had high fever, their temperature ranging up to 108 degrees Fahr, or 6 degrees above normal temperature. A sheep killed ten days afterwards, and was found with a spleen of 3 oz., a liver 14 oz., and two kidneys 4 oz. None of the sheep died of the tick fever, and they are now almost quite well. Dr. Hunt does not consider these experiments worth much, as it is quite possible the blood of a healthy bullock if injected into horses or sheep might have a disturbing effect. Concerning innoculation of sheep, Messrs. Kilborne and Smith say:-" Since sheep and cattle are so closely related, it was thought that the disease might be induced into them." And, as a result of their experiment, say:"Though the innoculation was made somewhat late in the season, the outcome plainly indicated no susceptibility of sheep to this disease." Ticks placed upon sheep by Dr. Hunt attached themselves, but did not produce fever. Rabbits. Experiments gave negative results. Pigeons.-Negative results. Guinea Pigs.-Negative results.

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Reference to Plates:

II. 1. Male seen from above, nat. size; 2. Female seen from above; 2a. Nat. size; 3. Male seen from below; 4. Female seen from below; 5. Clan and pulvillus; 6. Lower surface of first, second, and third segments of leg; 7. Spiracle or periteme.

III.-1. Front foot, showing single spur; la. Supposed sense organs; 2. Hind foot, showing double spur; 3. Head of female; 4, 4a, 4b, 4c. Female ticks, natural size, shown at different stages of feeding; 5. Egg; 6. Young tick; 7. Dorsal surface of the mouth parts of female-(a) mandible, (b) labrum, (c) palpus, (d) mouth or ring, (e) spots covered with papilla; S. Labrum and mandibles; Sa. Papille enlarged; 9. MandibleX-Busk's organ, use unknown; 10. Mouth parts of young tick.

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Notes on Ham and Bacon Curing.

By J. L. THOMPSON.

DISSOLVE "Black Horse" brand Liverpool coarse salt in water until the liquid is strong enough to float a potato. To every gallon of this liquid add:

lb. sal prunella

lb. saltpetre.

4 lb. brown sugar.

Dissolve thoroughly; add lb. whole spice to every gallon (sewing the spice in a cotton bag to prevent it mixing with the pickle).

Boil the pickle for an hour; when cold it is ready for use. This pickle can be kept in constant use if it is boiled every two months, and replenished with spice, sugar, &c.; boiling causes all blood, fat, &c., to rise to the surface, when such matters can be easily skimmed off.

Pickle properly looked after becomes stronger and more valuable with age, and will last a long time.

The pork must be cold, or it will not take the salt properly; the colder the flesh the easier it is to cure, proving the advantages of a refrigerator. Pump pickle into the shoulders and hams; from two to four injections in the shoulder, and two to three in the hams according to their size.

Have bacon tank No. 1 empty. Cover bottom of tank with a thin layer of salt, then place a layer of bacon, taking care, should any of the sides overlie each other, to put a sprinkling of salt between. Sprinkle salt all over the pork, and also sprinkle very lightly with saltpetre; then pack another layer of bacon crossways upon the first, and so on until all the bacon is in tank. When packing the tank, keep every layer as nearly level as possible. Batten the meat firmly down, and cover the whole with pickle. If using new pickle, add one pound of brown sugar to every ten sides, dissolving it in the pickle before use.

Miss one whole day before turning the bacon into No. 2 tank, viz.:Bacon put into No. 1 tank on Monday should be turned into No. 2 tank on Wednesday, and into No. 3 on Friday. The bacon will be ready to take out of pickle on Monday, giving it seven days in tanks.

Use saltpetre in No. 1 tank only.

Stacking-Mark off part of the floor for stacking the bacon upon as it comes from tanks. Cover the space with salt; then put a layer of bacon, covering it with a light coat of salt; then another layer of bacon crosswise to the first, and so on, taking care to have layers level, and as much pressure on the pumped parts as possible. For the first fortnight turn the stacks twice a week, and once a week for the other two or three weeks. The bacon can then be washed and smoked, or hung up in the green state (unwashed) until required.

Hams when cut from the side.

Keep tanks and pickle for hams only. Follow instructions as given for bacon, with the addition of rubbing the face of every ham with brown sugar before covering with salt and saltpetre. After seven days take hams out of tanks and rub brown sugar over their faces; place them singly in rows, resting on a support to keep them level; then salt. For this purpose a room should be set apart, and drained into a small well in the floor, as the pickle that comes from the hams is worth keeping.

Leave the hams in the sugar-room one week; go round them every morning and cover any bare patches with salt and sugar.

Take the hams from the sugar-room, brush them with a dandy brush, to remove any slime that may have appeared on them, and stack them two deep in salt. The third week stack them three deep, and the fourth week four deep. After the fourth week build them into a square stack and turn it every week for four weeks, giving the hams a good pressing.

When washed and soft they can easily be batted into shape.

The hams are now ready for washing and smoking. Use ham pickle for pumping.

Lard.

IN a recent communication to the Department, Messrs. Elliott Bros., manufacturing chemists, mentioned that difficulty is experienced in procuring in this Colony lard of the best grade. Messrs. Elliott mention that they use a considerable quantity of this commodity annually; and in response to their suggestion, Mr. Thompson, Principal of the Hawkesbury Agricultural College, has drawn up the following note on the preparation of the article.

The best quality of lard is obtained from the abdominal fat of the animal; the intestinal fat, trimmings, and refuse, yield an inferior quality.

It melts at 78° to 88° Fahr.; and if perfectly pure has no tendency to become rancid; but there is generally sufficient impurity present to develop a change in the olein of the fat, which gradually exhibits itself by a yellow colour and rancid odour and taste.

On a large scale it is "rendered" in vats heated by coils of steam pipes; the waste matter being used for making dog-biscuits, &c.

The yield may vary from 30 lb. up to 50 lb. per pig, or even more.

On a small scale it is conveniently rendered in a water bath over a fire as follows: Take two billypots (say 6 and 8 quarts capacity respectively, or any convenient sizes), put the small one inside the large one, and pass a piece of straight fencing-wire through all four handle-holes to keep the inner billy in its place; fill the outer larger billy with water, to within 6 inches of the top; put the fat to be rendered in the inner billy; raise the temperature of the water sufficiently to thoroughly liquefy the fat, and strain into bladders or clean tins. If desired, the liquid fat may be washed by stirring it into cold water, allowing it to stand over-night; by morning the fat will have all risen to surface of the water and solidified. The crust of fat may best be taken off by loosening it round the edges, and placing a clean board, the shape of the cake of fat, on its surface, and turning the whole upside down; the water runs away, and it will be found that a certain amount of discoloured matter will rest on the (original) under side of the crust; this can be removed, and the remainder will be very pure and clean.

By this system the risk of burning, and thus spoiling, the lard is practically done away with.

The trade in lard is an extensive one. A large amount is used in domestic cookery, and by chemists, and good, pure, native-made lard commands a ready sale at remunerative rates.

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