 James Tomison , who became a keeper in 1861 , wrote of the bird migrations visible from the tower : " Hundreds of birds are flying about in all directions , crossing and re @-@ crossing one another 's flight , but never coming into collision , all seemingly of the opinion that the only way of escape out of the confusion into which they have got is through the windows of the lantern " . A fog bell had been installed by then , one of only two operating in Scotland at the time . 
