AN AMATEUR (Oxford). _We are not of opinion that Mr. Talbot could restrain any one from taking collodion portraits, as patentee of the Talbotype process. It is done in many parts of London daily without any permission.--See _Times'_ Advertisements, &c._ C. E. F. _We think you use too strong a solution of the ammonio-nitrate of silver: thirty grains to the ounce of water, and then redissolved with the strong liq. ammon., give to us most satisfactory result,--the paper being prepared before with chloride of barium, chloride of sodium, and chloride of ammonia, of each half a drachm to the quart of water, in which half an ounce of mannite, or sugar of milk, has been previously dissolved. When sufficiently printed, put it into the hypo. sulph. solution, without previous immersion._ H. L. L. _We shall be happy to render you the best assistance we can, if you will communicate with us again. For iodized paper we may safely refer you to our advertising columns._ _A few complete sets of_ "NOTES AND QUERIES," Vols. i. _to_ vi., _price Three Guineas, may now be had; for which early application is desirable._ "NOTES AND QUERIES" _is published at noon on Friday, so that the Country Booksellers may receive Copies in that night's parcels, and deliver them to their Subscribers on the Saturday._ * * * * * NEW ACHROMATIC MICROSCOPES on MR. PRITCHARD'S construction, Micrometers, Polarizing Apparatus, Object glasses, and Eye-pieces. S. STRAKER supplies any of the above of the first quality, and will forward by post free a new priced List of Microscopes and Apparatus. 162. FLEET STREET, LONDON. * * * * * PURE NERVOUS or MIND COMPLAINTS.--if the readers of NOTES AND QUERIES, who suffer from depression of spirits, confusion, headache, blushing, groundless fears, unfitness for business or society, blood to the head, failure of memory, delusions, suicidal thoughts, fear of insanity, &c., will call on, or correspond with, REV. DR. WILLIS MOSELEY, who, out of above 22,000 applicants, knows not fifty uncured who have followed his advice, he will instruct them how to get well, without a fee, and will render the same service to the friends of the insane.--At home from 11 to 3. 18. BLOOMSBURY STREET, BEDFORD SQUARE. * * * * * SPECTACLES.--WM. ACKLAND applies his medical knowledge as a Licentiate of the Apothecaries' Company, London, his theory as a Mathematician, and his practice as a Working Optician, aided by Smee's Optometer, in the selection of Spectacles suitable to every derangement of vision, so as to preserve the sight to extreme old age.