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This, delivered at Darlington, cost, in April, 47. 108. per ton, for cash for a 5-ton lot, which was decidedly cheap.

3. Bones, Bone-meal, &c.

Bones generally undergo a process of partial boiling, for the purpose of extracting the fatty matter from them. This is, in a measure, necessary when the bones are subsequently used for dissolving with acid, in order to make dissolved bones. The process of boiling, if not carried too far, should only remove the fat and grease attaching, but not take out the nitrogenous matter. In the "steaming" of bone, which is a different process, the nitrogenous matters are for the greater part removed, to form glue, size, &c. ; and "steamed" bone, or (as it used to be, though incorrectly, called) "boiled" bone, is left. It is well that these distinctions should be understood, and the use of the terms "raw bone" and "degelatinised bone"-to represent respectively bones which have had only the fat removed, and those from which the nitrogenous matters have in great measure been removed also is to be recommended. Occasionally samples of raw bone, which are crushed and sold as such, without any preliminary treatment of boiling, &c., are met with. The following are analyses of such :

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Though still procurable, and at very reasonable prices, Peruvian guano hardly appears to be used to such an extent as formerly. A sample of the more phosphatic kind which gave—

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was exceedingly cheap at the price, in April, of 47. 10s. free on rail. Another sample, analysing

Ammonia

Total phosphates
Potash

Per cent.

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was likewise cheap at 51. per ton, in Liverpool, also in April. High qualities, giving 12 to 14 per cent. of ammonia, are still obtainable at fair rates.

5. Basic Slag.

The higher quality and superior grinding of this material have been referred to already. A good sample was the following :--

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This cost 41s. 6d. per ton, delivered near Shrewsbury. But care has to be exercised in the purchase of basic slag, which may not by any means always come up to the guarantee given. The following are instances of low quality or inferior grinding :

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Soot is always of variable quality, and, when used, as it often is, for top-dressing of cereals, it is important that the active constituent, sulphate of ammonia, should be present in fair quantity. The two following materials were offered, each as soot," and at the same price, viz. 27. per ton. As the analyses show, they were very different

Moisture

A

1 Organic matter and salts of ammonia 25-47
Oxide of iron, &c.

Sand

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1 containing nitrogen.

equal to ammonia

66

B

Per cent.
20.60

Per cent.

664

68.26

17.94

10.73

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The first-named was a very poor material, and, from its poverty

in ammonia, not at all suitable in ordinary quantities for a top

VOL. X. T. S.-40

Y Y

dressing for wheat; whereas the second sample was a very good one indeed, and well worth the money.

7. Miscellaneous Fertilisers

(a. Carbide Refuse; b. Lawn Sand).

(a) The extension of the system of acetylene gas lighting for country houses led to the suggestion on the part of a member of the Society that the calcium carbide refuse might have special manurial value. A sample of the refuse sent to me gave on analysis:

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This had no practical value beyond that of the lime contained in it, and was, moreover, not in a condition capable of ready application.

(b) A material sold as "Lawn Sand" is believed to have very potent powers in destroying plantains and other weeds on lawns. A sample sent me for examination was found to consist practically of ammonia salts (sulphate of ammonia) and sand, the analysis being :

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The price of this was 34s. per cwt., so that sulphate of ammonia at 10s. per cwt. would go nearly twice as far and cost only about one-third the price. Like many other materials of its class, what the "Lawn Sand" practically does is to shrivel and burn up (as ammonia salts in excess will) the plants on which it immediately falls, and subsequently, when the excess is washed away, the ammonia salts exercise a forcing effect upon the grass

around.

The following is the List of Analyses made for Members of the Society for the twelve months, December 1, 1898, to November 30,

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THE applications dealt with by the Zoologist during the past year have been unusually varied in character. The inquiries have had reference to more than fifty different species of animals, for the most part injurious insects and parasitic worms. In many instances, of course, the same attack has been reported from various localities, but no pest would appear to stand out very conspicuously as characteristic of the past season. The "pear midge," Diplosis pyrivora, seems to be annually encroaching upon new orchards, and special attention is called to this pest in the present report. At the same time an attempt is made to assist the fruit-grower to distinguish the different fruit-eating pests of the apple and pear, which are constantly confused.

It may be mentioned that in some cases advice has been sought

by members of the Society with regard to insect pests in foreign lands.

HORSE BOT-FLIES.

In May some grubs taken from a horse were sent for identification and advice. They proved to be the larvæ of the less common horse bot, Gastrophilus hæmorrhoidalis.

The

This species and the more familiar bot-fly G. equi, have, broadly speaking, the same habit of life—that is, they both lay eggs on the exterior of the horse, attaching the eggs to hairs. hatching grubs cause an irritation which induces the horse to lick the spot, and thus convey the larvæ to its stomach, where they fix themselves and remain for a considerable time, feeding upon the products of the inflammation they set up. When mature, they pass out by the rectum and turn to pupa in the ground, and from these the fly emerges in due time.

There are certain differences, however, between the habits of the two species. The common bot usually attaches its white eggs to the fore limbs of the horse, and the whole period passed by the grubs in the alimentary canal is spent in the stomach. G. hæmorrhoidalis lays its eggs, which are dark-coloured, on the hairs of the lips, and the grubs let go their hold in the stomach some time before they are ready to leave the horse, and, passing down the intestine, fix themselves for a period in the rectum, near the anus. In this position they may attract attention, so that the attack is more readily observed than in the case of the common bot, which may easily pass out unnoticed in the droppings.

The bot grubs vary in appearance during their growth, but when nearly mature they are bottle-shaped creatures with hooked heads, and double rows of hooked spines on all the rings except the last. The spiracles, or breathing holes, are on the blunt hind end of the grub. The common bot is whitish, but the grub of G. hæmorrhoidalis is reddish, and not so strongly spined, as well as being somewhat smaller.

Horses not frequently groomed, and spending much time in the fields, are most subject to attack.

Occasionally, bots have been known to stop on their way to the stomach and attach themselves to the orifice of the breathing tube, causing much disturbance of the respiratory process, and even asphyxia.

There is very great difference of opinion as to the amount of injury inflicted by the bots. Frequently the stomachs of horses which have died from other causes are found to contain numbers of the grubs, whose presence, during life, was not in the least suspected. The irritation they set up cannot fail, however, to be detrimental to the horse's health, even where no ill effects are obvious. The fact seems to be that a horse in good condition and well fed can endure the presence of numerous bots in the stomach without great inconvenience, but if the animal is in poor condition, gastric enteritis, perforation of the stomach, and death may result.

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