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few grains of the common cochineal of the shops in warm water for 24 hours, they will observe them to swell up to their original shape; so that the legs, antennæ, and proboscis may be discovered. What is remarkable in the proboscis is, that we shall find in many of them the ends of two fine hairs or filaments remaining, with which it forms its web, not unlike the silk worm; which always spins its cocoons with 2 threads, which as they come out, unite together with the natural gluten of the animal. And if this animal, thus expanded by moisture, be opened in a watch glass with a fine lancet in a little water, a great number of eggs, with the young animals in them, may be discovered, which will exhibit a very agreeable scene of a most vivid crimson hue.
As soon as the female insect is delivered of its numerous progeny, it becomes a mere husk and dies; so that great care is taken in Mexico, where it is principally collected, to kill the old ones while big with young, to prevent the young ones escaping into life, and depriving them of that beautiful scarlet die so much esteemed by all the world.
In plate 16 are exhibited several views of both the male and female insect in various states and positions, and also both in their natural size, and as magnified by the microscope; the former marked with the small letters of the alphabet, and the latter with the corresponding capitals. Thus,
A, denotes the female cochineal insect on its back magnified. B, the same on its belly magnified. c, the male cochineal insect as it walks, magnified. D, the male cochineal insect with its wings extended, magnified. E, the male cochineal insect in a side view flying, magnified. F, the male insect as it is found without wings, magnified. G, the silk-bag which the male insect spins before its wings are expanded. H, the silk-bag cut open which discovers the head of the male insect magnified. 1, the appearance of the female when it first begins to spin, magnified. K, L, M, the front, back, and side views of the female cochineal insect, when it comes to perfection, and big with young, magnified.
a and b, the natural size of the female cochineal insect when it creeps about. c, d, e, the natural size of the male cochineal fly in three different views. f, the male insect as it is found without wings. g, the silk-bag of the male fly. h, the top of the silk-bag cut open to show the head of the male fly. i, the female before it spins. k, l,m, the natural size of the female cochineal when it becomes fit for use, in three views,
END OF THE FIFTY-SECOND VOLUME OF THE ORIGINAL.
1. Of the Sun's Distance from the Earth deduced from Mr. Short's Observations
relating to the Horizontal Parallax of the Sun. By Peter Daval, Esq., V.P. of R.S. to James Barrow, V.P. of R. S. p. 1. Vol. LIII.
According to Mr. Short, the mean horizontal parallax of the sun is 8".65.. Now this parallax is the angle which the semidiameter of the earth subtends, as seen from the sun. Therefore as 8".65 is to 360° (the whole periphery of a circle) so is the semidiameter of the earth to the periphery of the orbit of the earth round the sun. But 8".65 is very nearly the 149826th part of 360°, as. may be easily proved by division. According to the latest observations, the mean. semidiameter of the earth is 3958 English miles, which being multiplied by 149,826, produces 593,011,308 miles for the circumference of the orbit of the earth. The distance of the earth from the sun is the semidiameter of this orbit: and the periphery of the circle is to its semidiameter very nearly as 6,283,185 to 1. Therefore if we divide 593,011,308 by 6,283,185, the quotient, which is very nearly 94,380,685, will give the mean distance of the earth from the sun in. English miles..
As the orbit of the earth is an ellipsis, not a circle, the distance of the earth. from the sun will be greater in its aphelion, and less in its perihelion than here assigned..
II. Observation of a Comet, which appeared in May 1759, made at the Hague..
Mr. Gabry observed the place of the comet on several days, as below.
Ill. Observation of a Fiery Meteor, made at the Hague, Dec. 21, 1758.
Peter Gabry, F.R.S. From the Latin. p. 5.
About 8. in the evening of that day a remarkable light, or shining meteor, appeared in the western part of the heavens, though the sky was then hazy and calm. The air was temperate, the thermometer indicating 47°. Sometimes the western sky seemed to burn, and the air with the lower clouds as if changed into flames and smoke. At the same time also there shot up bright flames almost tothe zenith.
A little after, the shining appeared very white, like a continued mass of fire; 'at first thin and weak; then increasing, it would extend from the north to beyond the west, not unlike the light appearing in the horizon, just before sun-rise
Then it would assume a red colour, so as it seemed to be a fire broke out in the vicinity of the city; and at times ascending higher above the horizon, and illuminating the surrounding houses. This metecr disappeared at half past 8 o'clock.
IV. On a Remarkable Decrease of the River Eden, in Cumberland. By I'm. Milbourne, Esq. p. 7.
In the night between the 28th and 29th of December, 1762, the river Eden, at Armathwaite, fell at least 2 feet perpendicular. The decrease of the water was so sudden, that several trouts and young lampreys had not time to save themselves, but were found the next morning frozen to death. Of the former, eye-witnesses can speak to 15, of the latter 200, all found in the extent of no more than 40 yards. And several dozens of young lampreys were easily taken up alive by the hand in the shallows. The suddenness of the water's decrease may be so far ascertained as follows. The miller of Armathwaite-mill left off grinding at 12 o'clock that night, there not being then sufficient water to work the mill. He went to the mill the next morning at 6, and there was not then water enough to turn the wheel round. It has not been known, that the river Eden was ever so low at this place, by a foot, in the driest summer. The water continued in this state till about 11 o'clock of the morning of the 29th, and then gradually increased (no rain or snow falling) till about 1 in the afternoon, by which time it had risen about a foot perpendicular.
V. Of the Rain fallen in a Foot-square at Norwich. By Mr. Wm. Arderon, F. R. S. p. 9.
99 14.4 6.9 7.4 5.5 4.3 12.8 4.7 4.4 13.6 2 18.7 10 12.9
1749. 1750. 1751. 1752. 1753. 1754. 1755. 1756. 1757. 1758. 1759. 1760. 1761. 1762.
Total inches deep.
12.4 13.9 6.7 11.1 5.8 2.5 5.1
VI. Effects of Electricity applied to a Tetanus, or Muscular Rigidity, of four Months' Continuance. By I'm. Watson, M.D., F. R. S., &c. p. 10. Catherine Field, a girl in the Foundling Hospital, aged about 7 years, and otherwise a healthy child, having been disordered a few days with what were considered as complaints arising from worms, was observed, on Thursday, July 8, 1762, to open her mouth with great difficulty. This particular circumstance increased so much, that by the Sunday following, when Dr. W. first saw her, her teeth were so much confined, it was with difficulty that even liquids could be admitted into her mouth. She had 2 days before parted with 2 worms, and had several very offensive stools. Her breath was now, and had been for some days, very fetid. Though her jaw was locked very close, she was without pain; even in the temporal and masseter muscles, whose office is to bring the under jaw to the upper; and which, in this instance, were tense, hard, and spasmodically affected. She was feverish, her pulse was quick, and her flesh hot; and she had had but very little sleep.
On Monday, July 12, he visited this poor girl in consultation with Dr. Morton. They found she had had a restless night; her fever was high, and it was infinitely difficult to introduce any thing between her teeth. As there had been no wound, no eruption repelled, they were of opinion, from her offensive breath, and other indications, that the spasm of her jaw was symptomatic, either of worms or foul bowels. Whatever was admitted into her mouth, was swallowed without difficulty; neither in this state of the disease was her breathing at all affected. For near 3 weeks the disorder confined itself to the jaw, during which time she was constantly feverish. At times indeed her fever ran very high, and her pulse beat 130 strokes in a minute. At other times it beat only about 100; but never for these 3 weeks was it slower than that number.
Notwithstanding their best endeavours, the disease not only continued, but the rigidity communicated to the muscles of her neck, so that she could not move her head in the least and from pains shooting down her back, they had reason to apprehend, and which indeed did soon after happen, that the muscles of her back would soon likewise be rigid. After the back was affected, the disease extended very fast; so that by the end of Sept. almost all the muscles of her body were rigid and motionless. To be somewhat more particular; the rigidity from the temporal and masseter muscles had extended to the cheeks, to the neck, breast, abdominal muscles, all those of the back, the right arm, the hips, thighs, legs, and feet. Nor were they by any force, that could be exerted with safety, to be extended. By the rigidity and contraction of the large and long muscles of the back, the os sacrum and hips were drawn towards the shoulders; so that the spine formed a very considerable arch, By the superior strength of the flexor muscles of the thighs to that of the extensors, the legs were drawn up
almost to the thighs. Of all her limbs, the left arm only preserved any motion. Of this the joint of the shoulder was rigid, that of the elbow extremely impaired; but the wrist, hand, and fingers, were reasonably pliant. The various muscles subservient to the motions of the eyes, eyelids, lips, and tongue; as well as those internal ones at least, which assist in performing the offices of respiration and deglutition, did not seem in the least to partake of the rigidity.
From the end of Sept. to the middle of Nov. the disease, though it had exerted all its power, was at a stand. The feverish heat had left her, and her pulse beat generally between 80 and 90 strokes in a minute. But during this interval the poor patient was seized many times, both in the night and in the day, with violent convulsions in those muscles of the eyes, face, and right arm, which had any mobility left. These were so severe, that in her weak and wretched state, her attendants imagined every attack would put an end to her distresses. In this state, partly from the severity of the disease, and partly from the very small quantity of food which could be given to her, and which was only through a small opening made by extracting 2 of her teeth, and without which she must inevitably have been starved, she was emaciated in a most extraordinary manner. Her belly was contracted, and drawn inwards towards the spine. Her whole body to the touch felt hard and dry, and much more like that of a dead animal than a living one. This, added to the very great distortion of her back and lower limbs, heightened the disagreeable spectacle, and called to mind that admirable passage of Aretaus (cap. vi.), who when treating of and contemplating this disease, calls it 'inhumana calamitas, injucundus aspectus, triste intuenti spectaculum, et malum insanabile.' And he subjoins, that their distortions are such, that they cannot be known by their most intimate friends; which in this case was most strictly true.
During the continuance of this disorder, which had lasted more than 4 months, nothing had been omitted that they could suggest for her relief. While worms or foul bowels could be suspected to have occasioned this illness, as her stools were at first very offensive, and she had voided 2 worms, vermifuges of the most celebrated kind, linseed oil both by the mouth and by clysters, and such other medicines as tend both to carry off or destroy the worms, and cleanse the bowels, were assiduously administered. But no relief arising from these, bleeding with leeches at the temples, when her fever ran high, blisters behind the ears, round the neck, on the head, and in various parts of her body, were from time to time applied, as the disorder seemed to indicate. Nor during this time were antispasmodic remedies of various kinds omitted, and that in very liberal doses. Among these, as in several cases of locked jaws, related by authors of undoubted credit, opiates had been found to have been attended with great success, tinctura thebaica was copiously given. So that between the 12th of July