To find the value of the last term, the first member must be squared, the second member must be multiplied into the square, and the sign of the square root prefixed to the result, Thus, And prefixing the sign it becomes √ 784 = 28, which added to 36 found before gives 64. I am, Sir, your obedient servant, Tubney Park, March 5, 1815. JAMES LOCKhart. VIII. On the Use of the Cerebellum and Spinal Marrow. SIR, (To Dr. Thomson.) London, Feb. 14, 1815. In the 26th Number of your Journal is announced a discovery of the use of the cerebellum and structure of the spinal marrow, by Dr. John Cross of Glasgow. The following are the words of this announcement: "I was led about a year ago to conclude, that as the cerebrum is the fountain of sensation and intellect, the cerebellum must be the organ which supplies with nervous energy the face and other parts of the head, extrinsical of the brain, &c." Again, "I found that the spinal marrow is uniformly composed of four longitudinal divisions; two larger, anterior, which may be traced into the cerebrum, and two smaller, posterior, which may be traced into the cerebellum. I suppose that the two anterior portions are the organ of feeling; the two posterior, of motion." Now, Sir, this, though more vaguely stated, is so closely imitative of a statement which I actually published nearly six years ago, (in Archives of Universal Science, vol. iii. for July, 1809,) that I am compelled to beg you will do me the justice to point it out. The following is that statement. "From the peculiar opposition which subsists between the situation of the face and cerebellum, we are entitled to expect a similar opposition in their functions. As the face, therefore, occupied by the chief organs of sense, is the seat of sensation, so we might expect the cerebellum to be the organ of volition. This supposition receives additional force from the consideration that, as the organs of sense and the cerebellum are the first and the last portions of the nervous system; so sensation and volition are the first and the last of its functions. But this supposition is completely confirmed, when we recollect that the degrees of voluntary power always bear a close analogy to the various magnitudes of the cerebellum. In fishes, for instance, which possess amazing locomotive power, the cerebellum is often larger than the hemispheres! (P. 176, Op. Cit.) "The spinal marrow actually consists of four columns, of which two are anterior and two posterior. In the anterior columns ferminate the anterior fasciculi of all the spinal nerves; and these columns themselves, passing through the medulla oblongata, crura cerebri, and corpora striata, terminate in the hemispheres of the cerebrum. The anterior fasciculi of the spinal nerves are, therefore, their ascending fasciculi, and the anterior columns of the spinal marrow are its ascending columns. From the cerebellum again descend the posterior columns of the spinal marrow, and from these proceed the posterior fasciculi of the spinal nerves. The posterior columns of the spinal marrow are, therefore, its descending columns, and the posterior fasciculi of the spinal nerves are their descending fasciculi. Hence it is that these nerves and almost all the nerves of the body, have filaments of ascending and filaments of descending impression; are at once nerves of sensation and nerves of locomotion." (Page 142.) These quotations are, I believe Sir, sufficiently decisive as to the original author of those discoveries, which Dr. Cross intends to make the subject of his promised work. On this subject I may take this opportunity of observing, that my friend Dr. Spurzheim, (in his recent and very valuable work on the Anatomy, Physiology, and Physiognomy of the Brain,) has most certainly erred in denominating the cerebellum the organ of amativeness; for physical love no further depends on the cerebellum than that its degree is of course inseparably connected with the degree of voluntary power which is the proper function of that. organ; and hence it is, that the bull and stallion, having larger cerebella and more energetic voluntary power, have also a stronger propensity to physical love than the ox and cow, or the gelding and mare. Notwithstanding this objection however, I reckon that work the most important accession to our anatomical knowledge which ever has been made by any philosopher.* I remain, Sir, with great respect, your obedient Servant, ALEXANDER WALKER. * Since writing the above, Sir, I observe in the 27th number of your Journal a letter addressed to you by Dr. Leach, in which he indicates the large work of Gall and Spurzheim on the brain, published at Paris in 1807, as the original source of the discoveries so unfairly claimed by Dr. Cross. In answer to Dr. Leach, I need only say, 1. That Gall and Spurzheim's work actually contains no such state ments; and 2. That such statements are even in direct opposition to their dectrines. IX. On the Organic Remains in Plymouth Lime-stone. (To Dr. Thomson.) SIR, Citadel, Plymouth, March 9, 1815. In the last Number of the Annals of Philosophy there is a letter on my having found madrepores and shells in the lime-stone rocks at Plymouth. I should probably not have troubled you with a reply, had it not been stated that no shells had been observed in those rocks"in situ." It appears Dr. Leach is not aware of the discovery of a bed of lime-stone, abounding in shells, in the dockyard; and probably he is equally unacquainted with my communications to the Geological Society, and the specimens which I have sent for the use and inspection of its members. In addition to these, I could show him many varieties of shells which I have obtained from various parts of the rocks in this neighbourhood. I might add, about the same time. With respect to the madrepores, Dr. Lockyer, with some other friends, accompanied me in one of my visits to the quarry where I first found them; and he was of opinion, I remember, that they had more the appearance of imbedded stalactites than of animal remains; and, as I was of a different opinion, in sending some specimens to the Geological Society, I thought they might be interesting at least, if they did not tend to any useful purpose. As to the specimen in my possession of what Dr. Leach calls madreporite of a fine blood-red colour, I never considered it as such, but of a quite different nature. It was given to me several years ago, as coming from the neighbourhood of Stonehouse, or Devil's Point, and believing it to be the case, I have made many attempts to discover its native bed, though without success. I have no time for uninteresting or useless writing; but deeming the field of Science and Natural History open to all who are disposed to enter it, I shall continue my researches as hitherto, without giving, I hope, at least without intending to give, offence to any one; and certainly without assuming to myself the merit (if any) which others may think due exclusively to their own labours. I have the honour to remain, Sir, your obedient Servant, RICHARD HENNAH, Jun. ARTICLE XIII. Scientific Books in hand, or in the Press. Dr. Ronalds, of Coventry, is preparing for the Press a Translation of the celebrated little work of Cabanis on Certainty in Medicine. Mr. Huish will shortly publish a Scientific and Practical Treatise on the Management of Bees, with Plates. Mr. Parkes, the author of the Chemical Catechism, has in the Press a series of Chemical Essays, to be published in four pocket volumes, including a variety of Explanatory Notes, and an Index. It will be illustrated with more than 20 Copper-Plate Engravings. The observations in each line of the table apply to a period of twenty-four hours, beginning at 9 A. M. on the day indicated in the first column. A dash depotes, that the result is included in the next following observation. REMARKS. Second Month.-1, 2. Misty dull weather. 3. Cloudy: wind and rain in the night. 4. Temp. 49° at the time of observation : fine: Cumulus, beneath hazy Cirrus. 5. Cirrostratus and haze at sun-rise, and much dew, which did not evaporate: a very fine day: temp. 56° in the sun: p. m. Cumulostratus. 6. The same, followed by rain. 7. a. m. Overcast, dripping: p. m. wind N.W.: groups of Cumulostratus, Cumulus, and Cirrostratus, occupying the whole S. from one to two, coloured light indigo, with red haze above, and attracting the smoke. 8. p. m. The wind rose at S. with the usual hollow sound: a beating rain from that quarter ensued. 9. Misty, from a diffused Cirrostratus, and cloudy above. Water from a well, which might be 10° warmer than the air, emitted a visible steam. 10. Cloudy dripping at intervals. 11. The same: dark Nimbi passed in the S., the wind being W. p. m. 12. a. m. Misty: cloudy: wind and showers. 13. A wet windy morning, succeeded by a very fine day: Cumulus, with Cirrus. 14. A very moist Cirrostratus, a. m.: then fine, with various clouds: a little misty rain at night. 15. Much dew: the rain kept off till evening. 16. Windy: wet: a lunar corona. 17. Morning clear, with dew: then Cumulus, which becoming dense inosculated with the clouds above and with the smoke: a little rain p. m.: lunar corona. 18. Slight hoar frost: haze, passing to Cirrus and Cirrostratus. 19. Heavy Cumulostrati through the day: much wind. 20. Windy: wet: lunar halo at night. 21, 22. Cumulostratus: windy. 23. Fine. 24. Ramified Cirrostratus, indicating wind, which followed. 25. Blustering wind, with Cumulostratus, and strong evaporation: a little rain notwithstanding. 26. Showers, which laid the dust: a sudden clearing in the W. at sun-set. 27. Very white frost: a fine day, out of the smoke. 28. Hoar frost, and a frozen mist: a serene day. Third Month.-1. Hoar frost: Cirrus in a fine elevated veil, passing to Cirrostratus, and exhibiting between ten and eleven a solar halo a very fine day, the pollution of the smoke excepted. : RESULTS. Winds variable, but for the most part Southerly. Barometer: Greatest height. Least.... Mean of the period Thermometer: Greatest height. Least.... Mean of the period Evaporation, 0.80 inch. TOTTENHAM, Third Month, 10, 1815. .... .... 30-47 inches 29.785 57° 25 44.43 Rain, 1.18 inch. L. HOWARD. |