M. Niepce presented his first paper on the subject to the Royal Society in 1827, naming his discovery Heliography. What led him to the study of the principles of the art I have no means, at present, of knowing, but it was probably owing to the facts recorded by the Alchemists, Mrs. Fulhame and others, already mentioned. But M. Daguerre, who is a celebrated dioramic painter, being desirous of employing some of the singularly changeable salts of silver to produce a peculiar class of effects in his paintings, was led to pursue an investigation which resulted in the discovery of the Daguerreotype, or Photogenic drawing on plates of copper coated with silver.

To this gentleman--to his liberality--are we Americans indebted for the free use of his invention; and the large and increasing class of Daguerrean artists of this country should hold him in the most profound respect for it. He was not willing that it should be confined to a few individuals who might monopolise the benefits to be derived from its practice, and shut out all chance of improvement. Like a true, noble hearted French gentleman he desired that his invention should spread freely throughout the whole world. With these views he opened negociations with the French government which were concluded most favorably to both the inventors, and France has the "glory of endowing the whole world of science and art with one of the most surprising discoveries that honor the land."

Notwithstanding this, it has been patented in England and the result is what might have been expected: English pictures are far below the standard of excellence of those taken by American artists. I have seen some medium portraits, for which a guinea each had been paid, and taken too, by a celebrated artist, that our poorest Daguerreotypists would be ashamed to show to a second person, much less suffer to leave their rooms.

CALOTYPE, the name given to one of the methods of Photogenic drawing on paper, discovered, and perfected by Mr. Fox Talbot of England, is precisely in the same predicament, not only in that country but in the United States, Mr. Talbot being patentee in both. He is a man of some wealth, I believe, but he demands so high a price for a single right in this country, that none can be found who have the temerity to purchase.

The execution of his pictures is also inferior to those taken by the German artists, and I would remark en passant, that the Messrs. Mead exhibited at the last fair of the American Institute, (of 1848,) four Calotypes, which one of the firm brought from Germany last Spring, that for beauty, depth of tone and excellence of execution surpass the finest steel engraving.

When Mr. Talbot's patent for the United States expires and our ingenious Yankee boys have the opportunity, I have not the slightest doubt of the Calotype, in their hands, entirely superceding the Daguerreotype.

Let them, therefore, study the principles of the art as laid down in this little work, experiment, practice and perfect themselves in it, and when that time does arrive be prepared to produce that degree of excellence in Calotype they have already obtained in Daguerreotype.

It is to Professor Samuel F. B. Morse, the distinguished inventor of the Magnetic Telegraph, of New York, that we are indebted for the application of Photography, to portrait taking. He was in Paris, for the purpose of presenting to the scientific world his Electro-Magnetic Telegraph, at the time, (1838,) M. Daguerre announced his splendid discovery, and its astounding results having an important bearing on the arts of design arrested his attention. In his letter to me on the subject, the Professor gives the following interesting facts.

"The process was a secret, and negociations were then in progress, for the disclosure of it to the public between the French government and the distinguished discoverer. M. Daguerre had shown his results to the king, and to a few only of the distinguished savans, and by the advice of M. Arago, had determined to wait the action of the French Chambers, before showing them to any other persons. I was exceedingly desirous of seeing them, but knew not how to approach M. Daguerre who was a stranger to me. On mentioning my desire to Robert Walsh, Esq., our worthy Consul, he said to me; 'state that you are an American, the inventor of the Telegraph, request to see them, and invite him in turn to see the Telegraph, and I know enough of the urbanity and liberal feelings of the French, to insure you an invitation.' I was successfull in my application, and with a young friend, since deceased, the promising son of Edward Delevan, Esq., I passed a most delightful hour with M. Daguerre, and his enchanting sun-pictures. My letter containing an account of this visit, and these pictures, was the first announcement in this country of this splendid discovery."

"I may here add the singular sequel to this visit. On the succeeding day M. Daguerre paid me a visit to see the Telegraph and witness its operations. He seemed much gratified and remained with me perhaps two hours; two melancholy hours to him, as they afterwards proved; or while he was with me, his buildings, including his diorama, his studio, his laboratory, with all the beautiful pictures I had seen the day before, were consumed by fire. Fortunately for mankind, matter only was consumed, the soul and mind of the genius, and the process were still in existence."