In the same manner the pin passes through the calcarine fissure, perforates hippocampus minor, and emerges in the posterior horn of the lateral ventricle.

Again, we stick a pin into the collateral fissure, which is between the last two, and we find it comes up through the eminentia collateralis, a small eminence inside, just between the two hippocampi.

The posterior horn of the lateral ventricle had a good deal of fuss made about it at one time, because it was thought that it overlapped the cerebellum, or little brain, only in man; but it is now found that many monkeys have as good posterior horns as we have, perhaps better.

As the cerebellum has been mentioned, perhaps we may remark that it is a popular phrenological fallacy to consider it the seat of the animal propensities; it is now believed to have an excessively complex function, presiding to a certain extent partly over sensation, partly over motion, and partly over nutrition.

This chapter may show how wearisome anatomy is to read with its tiresome repetitions, which, however, are necessary for the sake of clearness.

"Stinks "-HS-How to use a blow-pipe-Students at work in squads-Dirt-Burning the demonstrator-What it is the fashion to say-Dispensing and pharmacy-These might be taught at the Pharmaceutical Society's Hall-Prescriptions -A substitute for "Gregory's powder "- An after-dinner mixture-" Dog Latin "- Children's enjoyment compared with that of adults -The man who had an "annual dinner every week.

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No diploma can be obtained unless you have attended a course of practical chemistry," or, as it is sometimes called, chemical manipulations," by far the most popular part of the science with most men.

At Oxford, indeed, the professors of the natural science schools have fitted up the laboratories to such perfection, that the undergraduates are quite fond of going there to "kick up stinks," as the phrase is; and this is the reason why natural science of every department is, at Oxford, included under the comprehensive though not euphonious term "stinks."

Certainly the Oxonians have seized on the most prominent feature of practical chemistry. By some noses the odours of the laboratory are even less endurable than those of the dissecting-room, and it seems, in

most schools, impossible to secure proper ventilation without producing draught enough to blow out the lamp; so men would rather get used to sulphuretted hydrogen than take half an hour to boil a test-tube.

This "sulphuretted hydrogen," like old offenders, has several aliases; it is also called "sulphide of hydrogen," "hydro-sulphuric acid," and "rotten-egg gas;" but all these are such long names that, as it is in constant use as a test, it is generally called " HS," its chemical symbol; and you will not be long in the laboratory before you find a little "HS" goes a very long way. We may remark that "HS" is found "native," "wild," or "free," in the mineral waters of Harrowgate, Cheltenham, Leamington, Gilsland, Moffat, and Strathpeffer.

But "HS" is not the only bugbear of the laboratory; you burn your fingers with the test-tubes; you spill strong acid on your clothes and hands, turning the former red and the latter yellow; your retorts will burst; and though you observe every precaution by covering your substance for the blow-pipe test with "microcosmic salt," or "black flux," you will, for some time, find the first puff scatters everything, and nothing can you "reduce," no matter what pains you take.

Patience, patience! When you know the different processes in your 'Practical Chemistry,' by Bowman, or Noad, or Odling, you will have learned how to manage your blow-pipe, though it seems so difficult at first.

It is quite easy when you have acquired the knack; but we have not seen the "knack" described intelligibly in any book yet, and we could not manage it till

we were taught this plan. "First try without a blowpipe; close your mouth, distend your cheeks, breathe quietly; you will soon discover that you can breathe comfortably without the least effort to keep your cheeks distended. All right; now try the same thing with the blow-pipe in your mouth. No; don't blow, only breathe. There, that's it; now you can blow away for half an hour, if you like, without stopping!" And so you can. You will be quite surprised to see how easily men acquire the "knack," when a little trouble is taken to teach them.

A stranger might easily while away an hour or two -if he did not mind the smells-watching a number of students at work in the laboratory; they are told off into squads and. placed at long tables, with chemicals and apparatus arranged for the various processes to be learned at each table. The squad at table A will perhaps practise "glass - blowing" to-day, while tomorrow they will change places with the squad at B, who are trying to collect gases under water. Squad C may be practising "acidimetry" and "alkalimetry”— squad D, "distillation;" and it is ludicrous to observe how disgusted they look at finding the water less pure after the process than before. Squad E will be taking the "specific gravity" of everything they can lay hands on, and losing much time and temper in trying to make slip-knots in refractory horse-hairs, for suspending in water the objects to be weighed; while squad F may be performing Marsh's test for arsenic. It is at this last table that retorts, Wolff-bottles, and Florence-flasks come to their untimely end; for most men set light to their "nascent hydrogen," as soon as it begins to be given off, without waiting till the air

is all expelled from the bottle. The explosion of the mixed gases makes a great noise, but fortunately people are very seldom hurt.

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But the best fun is testing for "unknown substances;" you derive no pleasure from manipulation till you reach this stage; but the last step in an analysis affords the same kind of gratification as we feel in putting the finishing stroke to an equation in algebra, the answer." It is all the more satisfactory when you have got it right "in spite of the book," as you are pleased to say; for the book told you such and such a reaction should produce a "yellow crystalline precipitate," yet all you found was a nasty, muddy, yellowish cloudiness. Still you guessed right. "Ah! had him there," you say, with a chuckle.

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Lord Palmerston is said to have defined "dirt "matter out of place;" and in performing analyses you will soon declare the definition true. Dust is the bane of the life of the young chemist, but besides this, he will often find his results obscured by the "impurities" of the common chemicals in the laboratory; for compounds of sodium, arsenic, and sulphur seem as difficult to eradicate as thistles from a pasture.

"How provoking! This must be Epsom salts; here's the magnesia detected in this test-tube, and here's the sulphuric acid demonstrated in that; yet here's soda shown as plain as a pike-staff in this one! What the deuce does Charlie (the demonstrator) mean by saying it consists of only one acid and one base? I'll serve him out!"

Yes, that's right; wrap a piece of paper round the top of the test-tube, heat it as hot as you can, go up to him with indignation expressed on your outraged