Chameleon.—Light Coloured Eggs.—Sitting Birds have no Scent.—Forget-me-nots.—Trespassing.—The Owner.—A Chase.—Capture.—Pintail Duck.—Drumming of Snipe.—Swallow-tail Butterfly.—A Perilous Adventure.

The young voyagers had by this time discovered that sailing about in the manner they were doing gave them tremendous appetites, and on this particular morning they found they had run short of bread and butter, so Jimmy was despatched to the little shop at Horning to procure some.

After breakfast they were lounging on deck waiting for a breeze. Dick was sprawling on the roof of the cabin basking in the sun. Frank was fishing for roach in the clear slow stream, and Jimmy was perusing the newspaper in which the provisions had been wrapped. It was a still, lovely morning. White clouds sailed quickly across the blue sky, but there was no breeze to move the marsh grasses and reeds, or to ripple the placid stream. A lark sang merrily far above them, filling the air with melody. Small birds chirped in the sedges, and the water-hens and white-headed coots sailed busily to and fro.

Jimmy looked up from his paper just as Frank pulled in a good sized roach, and said,—

"Do either of you know how the chameleon changes its colour?"

Upon receiving an answer in the negative he read as follows from the paper in his hand:—

"M. Paul Bert has laid before the French Academy a rÉsumÉ of the observations of himself and others on the colour-changes of the chameleon. They appear to be due to change of place of certain coloured corpuscles. When they bury themselves under the skin, they form an opaque background to the cerulescent layer, and when they distribute themselves in superficial ramifications, they either leave the skin to show its yellow hue, or give it green and black tints. The movements of the colour corpuscles are directed by two orders of nerves, one causing their descending, and the other their ascending, motions. In a state of extreme excitation the corpuscles hide below the skin, and do so in sleep, anÆsthesia, or death. The nerves which cause the corpuscles to go under the skin have the greatest analogy to vaso-constrictor nerves. They follow the mixed nerves of the limbs, and the great sympathetic of the neck, and do not cross in the spinal marrow. The nerves which bring the corpuscles upwards resemble in like manner the vaso-dilator nerves. Luminous rays belonging to the blue-violet part of the spectrum act directly on the contractile matter of the corpuscles, and cause them to move towards the surface of the skin."

"Now, can you tell me the plain English of that?"

"Read it again, Jimmy," said Frank.

Jimmy did so.

"Well, I am no wiser. Read it again more slowly."

Jimmy did so again.

"I give it up," said Frank. "What a thing it is to be a scientific man!"

"I take it," said Dick, rolling himself along the cabin roof towards them, "that it means that different coloured rays of light have corresponding effects upon coloured atoms in the skin of the chameleon. The rays of light will be affected by the colour of the place where the chameleon is, and the chameleon will be affected by the changed colour of the rays of light, so that if the beast were on a green lawn his colour would be green, and if on a brown tree-trunk his colour would be brown."

"That is my idea," said Jimmy; "but what is the good of using such stilted language, when the same thing might have been said in simple English?"

"I wonder why that water-hen keeps dodging about us in such a fussy manner," said Frank.

"I don't," replied Dick, "for there is her nest not a yard from our bows."

The mooring rope had parted the reeds, and discovered her nest, and Dick, on going to the bows had seen it. It contained twelve eggs, one of which was so light in colour as to be almost white, and one so small that it was only half the size of the others. Dick asked if it were because it was laid last, and if the pale one was so for a similar reason. Frank replied,—

"It may be so in this case, but it does not always happen so. Last year I tried an experiment with a robin's nest. I took out an egg each day, as it was laid, and still the bird went on laying until I let her lay her proper number, five. She laid fifteen eggs altogether, but they were all the same colour and size. So I expect that it is only an accident when the eggs are like these."

"Bell told me the other day that sitting birds have no scent," said Dick. "Is that true?"

"I am not quite sure, but I am inclined to think that they have not so strong a scent as at other times. This same robin which I have just been telling you about built in a hedge-bank close by a house, and cats were always prowling about, and I have seen puss walk right above the nest while the old bird was on. If birds would only have the sense to shut their eyes, we would often pass them over, but it is easy to see them with their eyes twinkling like diamonds."

"How pretty that clump of forget-me-nots is on the opposite bank! They seem to smile at you with their blue eyes," said Dick, who was keenly alive to all that was beautiful. "But what is that flower a little lower down, right in the water, with thick juicy stems and blue flowers. Is that a forget-me-not?"

"No, it is a brooklime, but it is one of the speedwells. There are more than a dozen sorts of speedwells, but the forget-me-not is the prettiest. Another name for the forget-me-not is water-scorpion, but it is too ugly a name for so pretty a plant," said Jimmy, full of his recent learning.

"Here comes a breeze at last," cried Frank, as their blue flag fluttered, and the reeds in the surrounding marsh bent their heads together and sighed. "Shall we explore Ranworth Broad?"

"Yes, but let us take Hoveton Great Broad first, and then we can go to Ranworth as we come back," answered Jimmy.

So they hoisted sail, and glided up stream with a freshening breeze, while swallows dipped in the river and whirled about them as they passed. While they were sailing steadily along with a breeze on their starboard beam, the flag became fouled in the block through which the halyard of the mainmast was rove, and Jimmy was sent up to put matters right. He clambered up the mast as nimbly as a monkey, and shook loose the flag from its ignominious position. When he had finished this he looked about him, and from his greater height he could see much further than his companions, whose view was limited by the tall reeds which shut in almost every portion of the rivers and broads. The boys did not know that they were near any of the latter, but Jimmy saw on their left hand a sheet of water sparkling in the sun and studded with many reedy islands. He cried out,—

"There is such a jolly broad to leeward! It looks so quiet and still, and there are no end of water-fowl swimming about in it. A little further on I can see a channel leading to it just wide enough for our yacht. What do you say to paying it a visit?"

His friends had not the least objection. Its being unknown to them was an additional reason for their including it in their voyage of discovery. Jimmy said he should stay on his lofty perch for a time and take the bearings of the country, but as they neared the entrance to the broad and turned off before going down the narrow channel, the boom swung further out, and the jerk dislodged Jimmy, who was only saved from falling by clutching at the shrouds, down which he came with a run. They surged along through the dyke with the reeds brushing their bulwarks, and tossing and swaying in the eddies which followed their wake, and after several twistings and windings they emerged upon the broad.

At the entrance to it was a pole with a notice-board upon it, which stated that the broad belonged to Mr. ——, and that any persons found trespassing upon it would be prosecuted.

"Hallo! do you see that?" said Dick.

"Yes, I see it," replied Frank, "but we could not turn back in that narrow channel, and now that we are on the broad we may as well sail about a bit. What a number of water-fowl there are!"

"I know Mr. —— by sight," said Jimmy. "He has a big blue yacht."

The little lake was so picturesque with its islands and "ronds" and broad floating lily-leaves, that the boys sailed about for some time before they thought of leaving it, and when they turned their faces again towards the river, what was their surprise to see a large yacht creeping along the connecting canal between them and the river. The reeds hid the body of the yacht from them, but its sails betokened that it was one of considerable size.

The boys wondered who it could be who had thought of paying the sequestered little broad a visit, never for a moment thinking of the owner, when the yacht shot out into the open water, and lo! it was a 'big blue yacht.'

"It is Mr. ——," said Jimmy.

"Now we shall get into a row for trespassing," said Dick.

"They have got to catch us first. If we can only dodge them, and get on to the river again, we can show them a clean pair of heels," said Frank, taking a pull at the sheet and trying to creep up to windward of the dyke. The blue yacht, however, stood by so as to meet them, and Frank saw, by the way she went through the water, even when her sails were hauled almost flat, that she could beat the Swan in sailing to windward. A gentleman stood up in the strange yacht and called out,—

"Bear, up alongside, you young rascals, and give me your names and addresses. I shall summon you for trespassing."

"Not if I know it," said Frank, bringing the Swan sharply round on her heel, and scudding away before the wind, followed by the other in full chase.

"Now, Jimmy and Dick, stand by the sheets, and when we get opposite the bottom of that long island, we will bring her sharp round the other side, and then they can't get across and meet us, and then we'll cut and run for the dyke."

They executed this manoeuvre very neatly, but the other was too quick for them, and instead of following them round the island, they turned back and made for the mouth of the dyke to intercept them, and at a much better angle of the wind than that at which the Swan had to sail.

"We shall come into collision," said Jimmy, as he took a hearty pull at the mizen sheet. "We cannot both get through the dyke."

"Never mind. We'll cram her at it. Stand by with the boat-hook to push the blue 'un off, Dick!" but as Dick stood ready with the boat-hook to push off, a man stood in the other yacht with his boat-hook to pull them in, and as Dick pushed, his adversary pulled. The two boats ran alongside for a few yards, and then were jammed together at the mouth of the creek, and Mr. —— stepped on board.

"Now what is the meaning of this?" he exclaimed angrily.

"We came into the broad out of curiosity, sir," said Frank; "and we could not see the notice-board until we were in the broad, and then we thought we might as well take a turn round before going out, but we are sorry you have caught us."

"Oh, are you really! Well, I want to preserve the broad for wild-fowl, so I don't like it to be disturbed; but where did you get this strange boat built?"

"We built it ourselves," answered the boys,—and then in reply to the inquiries, they told him all about it, and their object, and by the time all was explained to him they found that he was a very jolly sort of fellow, and he found that they were very pleasant, unaffected lads, and the end of it was that they lunched with him on board his yacht, and had full permission to go on the broad whenever they liked.

Frank's attention was arrested by a pretty, light grey duck swimming about in the centre of the broad.

"Is that a pintail duck?" he inquired of Mr. ——.

"Yes, and the only one on the broad, I am sorry to say. Its mate has been killed, and my man found the deserted nest with four eggs in it, among the reeds on the other side of the broad. If he has not taken it you may have it."

His man had not taken it, and in a few minutes the boys were the possessors of the eggs of this rare duck. The nest and eggs were of the usual duck type, and did not correspond in any degree with the extreme prettiness of the duck, which, with its mottled grey back and red-brown head and neck, is as fair to look at as it is good to eat.

The yachts were disengaged from their position without any damage, and the boys took leave of their entertainer with a cheer, and made for the river again.

"I hope all our adventures will end as nicely as that one," said Dick.

The wish was echoed by the others; but that very day they had an adventure which startled them considerably, and might have had very serious and fatal consequences. But of this anon.

Presently Dick said,—"I have noticed whenever we see a mud-bank that it is almost sure to be perforated by a number of small holes. What is the reason of that?"

"Oh, that is done by the snipes, when boring in search of food. Woodcocks will do it as well, and the woodcock's upper bill is so long and flexible that it can twist and turn it about in the mud with the greatest ease," answered Frank, who was always ready with an answer on ornithological subjects.

By and by Dick was observed to be looking all about with a very puzzled and curious air, peeping into the cabin, and scrutinizing the deck and the banks with the utmost attention.

"What is the matter, Dick?" said Jimmy at length.

"What on earth is that buzzing noise? It seems to be close to us, and I can't find out the cause of it. I did not like to ask before—it seemed so simple. Is it a big bee, or wasp, or what?"

Frank and Jimmy laughed heartily, and the former said,—

"Look up in the air, Dick."

Dick did so, and saw a bird which he knew to be a snipe, hovering somewhat after the manner of a kestrel, or windhover, as the country people sometimes call it. It was evident now that the noise came from it, but how was it produced, and why?

Frank could not answer either of these questions. It was a habit of the snipes in breeding time to rise and 'drum' in that way.

"No doubt he does it for a lark, and no doubt he thinks he does it as well as a lark, but no one seems to be sure how the noise is produced. The general opinion seems to be that it is caused by a vibration of the tail-feathers."

"Look!" cried Dick excitedly, diving into the cabin for his butterfly net. Over the marsh there fluttered one of the grandest of English butterflies, the swallow-tail. Large in size, being about four inches across the wings, which are of a pale creamy-yellow, barred and margined with blue and black, velvety in its appearance, and with a well-defined 'tail' to each of its under wings, above which is a red spot, the swallow-tail butterfly is one of the most beautiful of all butterflies. It is rare save in its head-quarters, which are the fens of Norfolk and Cambridge, and is justly considered a prize by a young collector. Frank immediately ran the yacht ashore, and Dick jumped out and rushed at the gorgeous insect with his net. Alas! he struck too wildly and missed it, and it rose in the air and flew far away, leaving Dick lamenting. Frank laughed and said,—

"Ah, you went at it too rashly. You should have given it him with more of the suaviter in modo and less of the fortiter in re. Here comes another. Let me have a try!"

Dick yielded up possession of the net to him, and he advanced slowly and cautiously to where the swallow-tail was sunning himself on an early tuft of meadow-sweet, which the warm weather had tempted to bloom earlier than usual, and to perfume the air with its strong fragrance on the last day of May.

Frank's approach had too much of the suaviter in modo, for the butterfly flew away long before he reached it. Frank forgot all about the suaviter in modo then. He dashed after it at the top of his speed, making frantic dashes at it with his net, and jumping over soft ground, with utter disregard to all dangerous places. He followed it for some distance, and then he suddenly disappeared, and to their dismay they heard him shouting loudly for help.

"He has got into a bog-hole," said Jimmy, "come along as fast as you can."

They ran with breathless speed to where he had disappeared, and so deceptive are distances on flat surfaces, that they were surprised to see how far he had gone. When they reached him they saw him up to his waist in the soft bog, whose bright vivid green would have shown its danger had he not been too eager in his pursuit of the butterfly to notice it. He was rapidly sinking deeper into the mud, which held him fast with cruel tenacity, and sucked him further into its horrid embrace the more he struggled to get out of it. He had taken a big jump right into the very middle of it, and he was too far from them to reach their hands. His face was pale, but he was cool and collected.

"All right," he said, "don't be frightened. I've got the butterfly, and if you will do what I tell you, I will soon get out of this fix. Dick, do you run to the yacht and get a rope, and you, Jimmy, get some reeds, and pitch them to me to put under my arms, and keep me from sinking further into this fearful mess."

Dick sped off like an arrow, and Jimmy tore up a bundle of reeds and threw them to his friend, who had now sunk up to his shoulders, and as the reeds broke beneath his weight he sunk deeper still.

"I hope Dick won't be long, or it will be all up with me, Jimmy," he said, and brave as he was, he could not keep his lips from quivering. Jimmy was in an agony of excitement. He took off his coat, and threw one end of it to Frank, but he could not reach him. Then he did what even raised a smile on Frank's face, imminent as was his danger. He took off his trousers and threw one leg to Frank, retaining the other in his hand. Pulling hard at this improvised rope, he held Frank up until Dick came tearing up with the rope trailing behind him.

"Thank God!" said Frank, and Jimmy then knew by his fervent tone how great he knew the danger had been. Clinging to the rope, he was hauled out by his companions, and so tightly did the mud hold him, that it took all their strength to drag him out. They walked slowly and quietly back to the yacht, and Frank changed his clothes, and lay down and was very quiet for some time, and they none of them recovered their usual spirits for some time after this occurrence.

The butterfly was set, and ever afterwards kept apart in Dick's collection as a memento of this time.

Before they went home again they had got several specimens of this handsome butterfly, and still better, they discovered numbers of the bright green caterpillars and chrysalides on the meadow-sweet and wild carrot, which grew in the marsh, and so were able to breed several fine specimens, enough for their own collection and for exchange.