An Instance of the Fingerpost (7 page)

Here Lower wagged his finger. ‘Ah, you have fallen too much under the influence of Mr Helmont, sir. There we will be in dispute.’

‘You do not accept this?’

‘I do not. Not that it matters, at the moment. Please continue.’

I regrouped my forces and rethought my approach. ‘We
believe
,’ I started, ‘we
believe
that it moves heat from the ferment of the heart to the brain, thus providing the warmth we need to live, then vents the excess into the lungs. But is that really the case? As far as I know, no experiments have proved this. The other question is simple: why do we breathe? We assume that it is to regulate the body heat, to draw in cool air and thus moderate the blood. Again, is that true? Although the tendency to breathe more often when we exercise indicates this, the converse is not true, for I placed a rat in a bucket of ice and stopped its nose, but it died none the less.’

Boyle nodded, and Lower looked as though he wanted to put some questions, but as he could see I was concentrating and trying to present my case well, he obligingly refrained from interrupting.

‘The other thing that has struck me is the way in which the blood changes consistency. Have you noticed, for example, that it alters colour after passing through the lungs?’

‘I confess I have not,’ Lower replied thoughtfully. ‘Although of course I am aware that it changes colour in a jar. But we know why, surely? The heavier melancholic elements in the blood sink, making the top lighter and the bottom darker.’

‘Not so,’ I said firmly. ‘Cover the jar, and the colour does not change. And I can find no explanation of how such a separation could occur in the lungs. But when it emerges from the lungs – at least, this is the case in cats – it is very much lighter in colour than when it goes in, indicating that some darkness is withdrawn from it.’

‘I must cut up a cat and see for myself. A live cat, was it?’

‘It was for a while. It may well be that some other noxious elements leave the blood in the lungs, are sucked out by passage through the tissue, as through a sieve, and are then exhaled. The lighter blood is purified substance. We know, after all, that the breath often smells.’

‘And did you weigh the two cups of blood to see if they had changed weight?’ Boyle asked.

I flushed slightly, as the thought had never even occurred to me. ‘Clearly this would be a next step,’ Boyle said. ‘It may be, of course,
a waste of time, but it might be an avenue to explore. A minor detail, though. Please continue.’

Having made such an elementary omission, I felt unwilling to continue and lay out my more extreme flights of fancy. ‘If one concentrates on the two hypotheses,’ I said, ‘there is the problem of testing to see which is correct: does the blood shed something in the lungs, or gain something?’

‘Or both,’ Lower added.

‘Or both,’ I agreed. ‘I was thinking of an experiment, but had neither the time nor the equipment in Leiden to pursue my ideas.’

‘And that was . . .?’

‘Well,’ I began, a little nervously, ‘if the purpose of breathing is to expel heat and the noxious by-products of fermentation, then the air itself is unimportant. So if we placed an animal in a vacuum . . .’

‘Oh, I see,’ Boyle said, with a glance at Lower. ‘You would like to use my vacuum pump.’

In fact, the idea had not occurred to me before I spoke. Curiously, Boyle’s pump was of such fame I had scarcely given it a thought since I had arrived in Oxford, as I had never dreamt of the possibility of using it myself. The machine was of such sophistication, grandeur and expense that it was known to people of curiosity throughout Europe. Now, of course, such devices are well enough known; then there were perhaps only two in the whole of Christendom, and Boyle’s was the better, so ingenious in design that no one had managed to reproduce it – or the results he attained. Naturally, its use was rationed very carefully. Few were even allowed to see it in operation, let alone employ it, and it was forward of me even to bring the subject up. I hardly dared risk a refusal; I had set myself the task of ingratiating myself into his confidence, and a rebuff now would have been hurtful.

But, all was well. Boyle thought the matter over a while and then nodded. ‘And how might you proceed?’

‘A mouse or a rat would do,’ I said. ‘Even a bird. Put it in the bell and extract the air. If the purpose of respiration is to vent fumes, then a vacuum will provide more space for the exhalations, and the animal will live more easily. If respiration requires air to be sucked into the blood, then the vacuum might make the animal ill.’

Boyle thought it over and nodded. ‘Yes,’ he said eventually. ‘A good
idea. We can do it now, if you like. Why not, indeed? Come along. The machine is prepared, so we can start immediately.’

He led the way into the next room, in which many of his finest experiments had taken place. The pump, one of the most artistic devices I had seen, stood on the table. For those who do not know it, then I suggest they consult the fine engravings in his
Opera Completa
; here I will merely say that it was an elaborate device of brass and leather with a handle connected to a large glass bell and a set of valves through which, propelled by a pair of bellows, the air could be made to pass in one direction, but not the other. By the use of this, Boyle had already demonstrated some marvels, including the disproval of Aristotle’s
dictum
that nature abhors a vacuum. As he said in a rare moment of jest, nature may not like it, but if pushed will be made to put up with it. A vacuum – an area of space voided entirely of content – can indeed be created and possesses many strange qualities. As I examined the machine carefully, he told me how a ringing bell placed in a glass chamber will stop making sound as the vacuum is created around it; the more perfect the vacuum, the less the sound. He said he had even constructed an explanation for the occurrence, but declined to inform me of it. I would see for myself with the animal, even if the rest of the experiment did not work.

The bird was a dove, a handsome bird which cooed gently as Boyle took it from its cage and placed it underneath the glass dome. When all was ready, he gave a signal, and the assistant began working the bellows with much grunting and a whooshing sound as air was propelled through the mechanism.

‘How long does this take?’ I enquired eagerly.

‘A few minutes,’ Lower replied. ‘I do believe its song is getting fainter, do you hear?’

I regarded the beast with interest – it was showing signs of distress. ‘You are right. But surely it is because the bird itself seems unconcerned with making a noise?’

Hardly had I spoken when the dove, which a few moments ago had been hopping around the dome with curiosity, fluttering against the invisible glass walls which it could feel but was incapable of understanding, fell over, its beak gaping open, its beady eyes popping and its legs flailing around pathetically.

‘Good heavens,’ I said.

Lower ignored me. ‘Why don’t we let the air back in, and see what happens then?’

The valves were turned, and with an audible hiss, the vacuum was filled. The bird still lay there, twitching away, although it was clear that it was very much relieved. Within a few moments, it picked itself up, ruffled its feathers, and resumed its attempts to fly away to freedom.

‘Well,’ I said, ‘so much for one hypothesis.’

Boyle nodded, and gave the assistant a nod to try it again. Here I must note the extraordinary goodness of this fine man, who refused to use the same animal in more than one type of experiment, because of the torture to the creature. Once it had served its turn, and given itself to the pursuit of humane knowledge, he either let it go or, if necessary, killed it.

Until then, I had never thought such an attitude attachable to any experimentalist other than myself, and I rejoiced to find at last someone whose sentiments were similar to my own. Experimentation must take place, this is certain; but sometimes, when I behold the faces of my colleagues as they cut, I think I see too much pleasure on their countenances, and suspect that the agony is prolonged longer than is necessary for mere knowledge. Once in Padua, a vivisection of a dog was interrupted when a female servant, grieved to hear the beast’s piteous cries as it was cut open, strangled it in front of a full audience of students, causing much dismay and protest at the ruining of the spectacle. Of the assembled multitude, I believe that only myself had sympathy for the woman, and was grateful to her; but then I was ashamed of the effeminacy of my concerns which, I think, came from my delight as a child in being read to from the life of St Francis, who loved and reverenced all things in God’s creation.

But Boyle came to the same conclusions, although (typically of the man) he did so in a far more rigorous fashion than myself and was, of course, uninfluenced by memories of the Assisi countryside. For, just as he believed that a gentleman should show Christian condescension to the lower orders, according to their merits, so men, the gentlemen of God’s creation, owed similar courtesy to the animals over whom they had dominion. While not scrupling to use men or animals as was
his right, he believed firmly that they should not be abused either. In that, good Catholic and fervent Protestant were in accord for once, and I liked Boyle the more for his care.

That afternoon, we used only a single bird. By means of careful study we ascertained that it was scarcely affected when only half of the air was removed, that it began to show signs of distress when two-thirds had gone, and was rendered insensible when three-quarters had vanished. Conclusion: the presence of air is necessary for life to continue, although, as Lower said, that did not explain what it did. Personally, I believe that as fire needs air to burn, so life, which can be likened to fire, needs it also, although I admit that argument by analogy is of limited use.

It was an appealing little animal, the dove we used to prise these secrets from nature’s grip, and I had my habitual pang of sorrow when we reached the final, necessary round of the experiment. Although we knew what the result would be, the demands of philosophy are implacable and all must be demonstrated beyond contradiction. So it was my voice which reassured the creature for the last time, and my hand which placed it back in the bell, then gave the signal for the assistant to begin pumping once more. I offered a small prayer to gentle St Francis when it finally collapsed and died, its song finally extinguished. It is God’s will that sometimes the innocent must suffer and die for a greater purpose.

THIS BUSINESS CONCLUDED,
Lower suggested I might like to dine with some friends later that evening whom he felt I might profit from meeting. It was kind of him and it seemed that the closeness to Boyle which an afternoon’s experiment entailed had placed him in a good humour. I suspected, however, that there was another side of his character, a darkness which warred with his natural good nature. For a flickering of a moment, while I laid out my thoughts to Boyle, I had felt a slight unease in his demeanour, although this had never come to the surface. I had also noticed that he had never given his own theories or elaborated his own thoughts; these he kept close to himself.

I did not mind; Boyle was Lower’s most important connection among the few gentlemen of standing who could help establish himself in his career and he was naturally concerned lest that patronage be diverted. But I contented myself with the assurance that I presented him with no challenge, and concluded that I could hardly attract his enmity. Perhaps I should have been more sensitive to his concerns, for it was a matter of character not of circumstance which made him uncomfortable.

My position had made me easy with all ranks of life; I admired and was beholden to Mr Boyle, but in all other respects I considered him my equal. Lower was unable to feel the same; although all are citizens of the Republic of Learning, he was often uneasy in such company, for he believed himself at a disadvantage due to a birth which, although respectable, gave him neither fortune nor people. Moreover, he lacked the talents of the courtier and in later years he never rose to any position of distinction in the Royal Society while men of lesser accomplishment took on its great offices. This was galling for a man of his ambition and pride but, for the most
part, this inner conflict was hidden, and I am aware that he did as much as his nature allowed to assist me while I was in Oxford. He was a man who liked easily, but then was seized by fear lest his affections be abused and exploited by others of a less trusting disposition than himself. The fact that earning position in England is so formidably hard merely heightened this aspect of his nature. I can say this now, as the passage of years has lessened my hurt and increased my understanding. At that time my comprehension was smaller.

It was as a result of his friendliness and enthusiasm, however, that I was led down the High Street that afternoon in the direction of the castle.

‘I didn’t want to mention it in Boyle’s presence,’ he said confidingly as we marched briskly along in the cold afternoon air, ‘but I have high hopes of getting hold of a corpse soon. Boyle disapproves.’

I was surprised by this remark. Even though some of the older physicians didn’t hold with the business at all, and it still caused considerable trouble among churchmen, it was accepted as an essential part of medical studies in Italy. Was it possible that a man like Boyle could disagree?

‘Oh, no. He has nothing against anatomising, but he feels I tend to become undignified about the matter. Which may be true, but there is no other way of getting hold of them without getting permission first.’

‘What do you mean? Getting permission? Where does this man find the body in the first place?’

‘He is the body.’

‘How can you ask permission of a corpse?’

‘Oh, he’s not dead,’ Lower said airily. ‘Not yet, anyway.’

‘Is he ill?’

‘Heavens, no. Prime of life. But they’re to hang him soon. After he’s found guilty. He attacked a gentleman and injured him badly. A simple case it is, too; he was found with the knife in his hand. Will you come to see the hanging? I must confess I shall; it’s not often a student is hanged, alas. Most of them join the Church and get livings . . . I’m sure there’s a witticism in there somewhere, if I phrased it rightly.’