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moved farther off, he faid it did not touch them; and at 22 inches it became invisible.”

This boy's eyes were operated upon at different times. First, the cryftalline lens of the left eye was extracted, and fome days after, the right eye was couched. The light was at first painful to his fight, and the objects he faw feemed to touch his eyes; but this painful fenfation diminished gradually, and about a month after, this author fays,

"The light now was not diftreffing to either eye, and when ftrong, he could readily difcern a white, red, or yellow colour, particularly when bright and fhining. The fun and other objects did not now feem to touch his eyes as before; they appeared to be at a fhort distance from him. The eye, which had been couched, had the most distinct vision of the two, but in both it was imperfect. The diftance at which he faw best, was five inches.

"When the object was of a bright colour, and illuminated by strong light, he could make out that it was flat and broad; and when one corner of a square fubftance was pointed out to him, he faw it, and could find out the other, which was at the end of the fame fide, but could not do this under lefs favourable circumftances. When the four corners of a white card were pointed out, and he had examined them, he feemed to know them; but when the oppofite furface of the fame card, which was yellow, was placed before him, he could not tell whether it had corners. or not, fo that he had not acquired any correct knowledge of them, fince he could not apply it to the next coloured furface, whofe form was exactly the fame with that, the outline of which the eye had just been taught to trace."

The fecond boy, whofe name was John Salter, had likewife been born with cataracts in his eyes. At feven years of age he was received into the above-mentioned hospital; and on examination it was found, that the pupils of his eyes contracted confiderably when a lighted candle was placed before them, and dilated when the light was removed. He was capable of diftinguishing colours with tolerable accuracy, efpecially thofe which were more bright and vivid. The left eye of this boy was couched on the 6th of October, 1806. The operation proved fuccefsful, and the following curious obfervations were made foon after.

"The eye," this author fays, "was allowed ten minutes to recover itself; a round piece of card of a yellow colour, one inch in diameter, was then placed about fix inches from it. He faid immediately that it was yellow, and on being afked its shape, faid, Let me touch it, and I will tell you. Being told that he mut not touch it, after looking for fome time, he faid it was

round.

round. A fquare blue card, nearly the fame fize, being put before him, he faid it was blue and round. A triangular piece he alfo called round. The different colours of the objects placed before him, he inftantly decided on with great correctnefs, but had no idea of their form. He moved his eye to different dif tances, and feemed to fee beft at 6 or 7 inches. His focal diftance has been fince afcertained to be 7 inches. He was afked whether the object seemed to touch his eye? he faid no; but when defired to fay at what diftance it was, he could not tell.

"On examining the eye 24 hours after the operation, the pupil was found to be clear. A pair of fciffors was fhown him, and he faid it was a knife. On being told he was wrong, he could not make them out; but the moment he touched them, he faid they were fciffors, and feemed delighted with the difcovery. From this time he was conftantly improving himself by looking at, and examining with his hands, every thing within his reach, but he frequently forgot what he had learned.

"On the 19th, the different coloured pieces of card were feparately placed before his eye; and fo little had he gained in 13 days, that he could not, without counting their corners one by one, tell their fhape. This he did with great facility, running his eye quickly along the outline, fo that it was evident he was ftill learning, juft as a child learns to read.

"On the 26th, the experiments were again repeated on the couched eye, to afcertain the degree of improvement which had been made. It was now found that the boy, on looking at any one of the cards in a good light, could tell the form nearly as readily as the colour."

From those two cafes, Mr. H. derives the following conclufions:

"That, where the eye before the cataract is removed, has only been capable of difcovering light, without being able to diftinguish colours, objects after its removal will feem to touch the eye, and there will be no knowledge of their outline; which confirms the obfervations made by Mr. Chefelden.

That where the eye has previously diftinguished colours, there must alío be an imperfect knowledge of diftances, but not of outline; which however will afterwards be very foon acquired, as happened in Mr. Ware's cafes. This is proved by the hiftory of the first boy in the prefent paper, who before the operation had no knowledge of colours or diftances; but after it, when his eye had only arrived at the fame ftate that the second boy's was in before the operation, he had learnt that the objects were at a diftance, and of different colours: that when a child has acquired a new fenfe, nothing but great pain or abfolute coercion, will prevent him from making ufe of it.

"In a practical view, thefe cafes confirm every thing that has been stated by Mr. Pott and Mr. Ware, in proof of cataracts in

children being generally foft, and in favour of cpuching, as being the operation beft adapted for removing them. They alfo lead us to a conclufion of no fmall importance, which has not before been adverted to; that when the cataract has affumed a fluid form, the capfule, which is naturally a thin tranfparent membrane, las to refift the preffure of this fluid, which like every other difeafed accumulation is liable to increase, and diftend it; and therefore the capfule is rendered thicker and more opaque in its fubftance, like the coats of encysted tumours in general.

As fuch a change is liable to take place, the earlier the operation is performed in all children who have cataracts completely formed, the greater is their chance of having diftinct vi fon after the operation. It is unneceffary to point out the advantages to be derived from its being dene at a more early age, independent of thofe refpecting the operation itfelf."

IV. Obfervations on the Structure of the different Cavities which confiitute the Stomach of the Whale, compared with those of ruminating Animals; with a View to ascertain the Situation of the digeftive Organ. By Everard Home, Efq. F. R. S.

The obfervations which are contained in this paper, tend to prove that the ftomach of the whale forms a ftep in the gradation towards the ftomachs of truly carnivorous animals. The fubject upon which they were made, was a Delphinus Delphis of Linnæus, or the mall bottle-nofe whale of Mr.

Hunter.

This author having in a former paper defcribed the ftomachs of the bullock and the camel, as examples of ruminants with and without horns, and intending to show the abovementioned gradation, begins the prefent paper with the defcription of the ftomach of the bottle-nofe porpoife, as an example of the whale tribe. He then proceeds to defcribe the cavities of the ftomachs of the different fpecies of the whale tribe, and accompanies the defcription with various appropriate remarks.

Two plates are annexed to this paper, the firft of which exhibits the first cavity of the ftomach of the bottle-nofe porpoife laid open; and the fecond plate reprefents the internal furface of the fecond, third, and fourth cavities of the fame ftomach.

V. On the Formation of the Bark of Trees. By T. A. Knight, Efq. F. R.S.

This author, in the first place, briefly ftates the various opinions refpecting the production and fubfequent state of the bark of trees, entertained by diverfe naturalifts, fuch as Malpighi, Grew, Hales, and Du Hamel, of which opinions

thofe

hofe of Malpighi and Hales are the most difcordant; the former of thofe authors faying, "that the cortical fubflance, which is annually generated, derives its origin from the older bark; and the interior part of this new fubftance is annually transmuted into alburnum, or fap wood; whilft the exterior part, becoming dry and lifelefs, forms the exterior covering, or cortex :" and the fecond contending that the bark is formed from the alburnum, and that it does not undergo any fubfequent transformation. Mr. Knight then points out the facts which are favourable to each of those two theories, and fubjoins a variety of experiments, inftituted by himself. The refults of thofe experiments throw much light on the fubject; yet leave the queftion undecided, as appears from the conclufion, in which this author fays,

"I fhall, therefore, not attempt to decide on the merits of the theory of Malpighi, or of Hales, refpecting the reproduction of the interior bark; but I cannot by any means admit the hypothefis of Malpighi and other naturalifts, relative to the tranfmutation of bark into alburnum; and I propofe to state my reafons for rejecting that hypothefis, in the next communication I have the honour to addrefs to you.

VI. An Investigation of the general Term of an important Series in the inverfe Method of finite Differences. By the Rev. John Brinkly, Ď. D.; F. R. S, &c.

It is impracticable to give our readers a diftinct account of the contents of this paper. It may in general be faid that its object is to remove a difficulty which attended the inveftigation of theorems relative to finite differences, which theorems were originally given by M. La Grange.

Meteorological Journal kept at the Apartments of the Royal Society, by order of the Prefident and Council.

This journal, which occupies 26 pages, commences on the 1ft of January, 1806, and ends on the 31ft of December of the fame year. It confifls, as ufual, of eleven columns under the titles of days of the year, Six's thermometer, time of making the obfervation, thermometer within, ther mometer without, barometer, hygrometer, rain, points of the wind, ftrength of ditto; and laflly, the ftate of the weather.

In those columns two obfervations are ftated for each day, one of which was taken in the morning, and the other in the afternoon.

From this journal it appears, that the greatest height of

the

1

the thermometer in the open air (viz. S5°) was obferved on the 10th of June; the leaft (viz. 26°) was oblerved on the 13th of March. The greatest height of the inercury in the barometer took place on the 12th of June, when it flood at 30,53 in. The leaft (viz. 28,65 in.) took place on January The quantity of rain that fell throughout the whole year, amounts to 20,427 inches. It is ftated at the end of the journal, that the declination of the magnetic needle, in June the abovementioned year, was 40° 8' weft,

the 12th.

ART. III. Education of the Lower Orders. A Second Letter to Samuel Whitbread, Efq. M. P. containing Obfervations on his Bill for the Establishment of Parochial Schools in South Britain. Alfo Supplementary Obfervations on the Religiouss Syftems maintained by the Monthly and Critical Reviewers, in their Strictures on the Author's First Letter to Mr. Whitbread. By John Bowles, Eja. 8vo. 122 pp. 3s. 6d. J. J. Stockdale, Rivingtons, &c. 1803.

IN

N Mr. Bowles's former Letter to Mr. Whitbread*, he remonftrated with that gentleman on "the unqualified praife" given by him to Mr. Lancaffer's Syftem of Educa tion. At the opening of this he obferves, that when Mr. W. brought forward his bill, for the establishment of parochial fchools, he took no further note of Mr. Lancaster's fyftem, whence he concludes that, on mature confideration, Mr. W. "became fatisfied of its tendency to endanger the established church, and indeed the interefts of Chriflianity in generalt.' Still Mr. Bowles complains, that no provifion was made in this fecond bill for educating children in the national church, the importance of which, to the ftate at large, he very juftly elucidates. He then very fuccefsfully rallies Mr. W. on his appearing to take for granted, that the mere inftructing of children in reading, writing, and arithmetic, was to convey improvement to them in religion, morality, and virtue. Certainly, as he very ably argues, the mere com

*Noticed by us in vol. xxx. p. 306.

+ A note on this paffage explains more fully the practical efforts of Dr. Bell, the real inventor of the plan, at Madras, Lambeth, and Chelfea, in the Royal Military Afylum, where the plan is purfued, without any mixture of the defects juftly afcribed to it when in the hands of Mr. Lancaster.

munication

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