40 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



having a focal length of about 55 feet. Its construction will 

 probably occupy three years. The appropriation initiating 

 this new work has already been made. 12 A^ XII., 538. 



LARGE TELESCOPES. . 



It is announced that the principal' refractor of the new ob- 

 servatory at Vienna is to be manufactured by Grubb, of 

 Dublin, the order for its execution having already been giv- 

 en. The object-glass will have an aperture of about 27 

 inches, according as the disks of glass turn out, these latter 

 being manufactured in Paris. The axes will all have their 

 friction relieved by anti-friction apparatus. The tube will be 

 entirely of steel ; and all the various motions of the instru- 

 ment, as well as the readings of the different circles, will be 

 available to the observer from the eye end. The telescope 

 will be mounted completely at Mr. Grubb's new workshops, 

 and covered by a corrugated iron roof fifty feet high. The 

 latter is but a temporary structure ; outside of it will be 

 erected a splendid steel dome originally designed by Mr. 

 Grubb, which, after being tested at Dublin, is to become in 

 Vienna the permanent shelter of the mounted refractor. 

 12^, XIL, 517. 



THE SPECTKOSCOPIC OBSERVATORY AT CALCUTTA. 



Rev. E. Lafont, Rector of St. Xavier's College at Calcutta, 

 has addressed the President of the Asiatic Society of Bengal 

 a letter in which he says he proposes to erect a spectroscopic 

 observatory at the college, where daily observations and 

 maps of the solar protuberances will be made. As this un- 

 dertaking is entirely for the benefit of science, he ventures to 

 request such assistance and subscriptions as may be necessary. 

 The total sum required is about ten thousand reals, toward 

 which the council of the society has contributed five hun- 

 dred. He states that the pressing invitation of his friend, 

 Professor Tacchini, first induced him to attempt the estab- 

 lishment of a spectroscopic observatory. Proceedings of 

 the Asiatic Society of Bengal, February, 1875. 



THE SOLAR ATMOSPHERE AND RADIATED HEAT. 



Mr. John Ericsson has published a portion of his solar in- 

 vestigations in a special memoir (privately printed in New 



